Physical and mental wellness, including prevention of illness, injury, and premature mortality.

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Mobilize Electric Bicycles

Submitted by Drawdown Admin on
Sector
Transportation
Mode
Cut Emissions
Cluster
Electrify Vehicles
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Parent riding electric bicycle with children seated in back carrier
Coming Soon
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Summary

We define the Mobilize Electric Bicycles solution as increased travel by bicycles that have an electric motor to supplement the effort of the rider, but require the rider to turn the pedals to activate the motor. Some sources refer to electric mopeds or motorcycles as electric bicycles, but those modes of transportation fall within Project Drawdown’s Mobilize Electric Scooters & Motorcycles solution and are not covered here. Also known as pedelecs or e-bikes, electric bicycles can be deployed as privately owned electric bicycles or as shared electric bicycles, which are available as part of bicycle sharing networks typically operated at the city level for short-term rental on a per-trip basis.

Income & work,Health
Air quality
Description for Social and Search
Mobilize Electric Bicycles is a Highly Recommended climate solution. Electric bikes reduce the need for car trips and so cut GHG emissions.
Overview

Electric bicycles use electric power to supplement the muscular effort of the rider. Like conventional bicycles and other forms of nonmotorized transportation, electric bicycles get some of their motive power from human muscle power, which in turn comes from food calories – a form of closed-loop biomass power with no emissions (see Improve Nonmotorized Transportation). Unlike conventional bicycles, however, electric bicycles get added power from electricity, which comes from the grid and is stored in a battery.

This partial reliance on grid electricity, as well as the production of the battery and electric motors, increases the carbon emissions and cost of an electric bicycle compared to those of a conventional bicycle. Nevertheless, electric bicycle emissions remain far lower than the emissions of cars (including electric cars), meaning that every passenger-kilometer (pkm) moved from a car to an electric bicycle achieves significant GHG emissions savings. 

Since the additional electric power enables electric bicycle riders to cover longer distances at greater speeds, climb larger hills, and carry heavier loads – and do it all with substantially less physical effort – electric bicycles can substitute for more car trips than conventional bicycles can. This can amplify electric bicycles’ potential carbon savings relative to conventional bicycles, even if the savings per pkm traveled are lower. Electric bicycles also tend to get used at high rates, and a large proportion of pkm by electric bicycle are pkm that would otherwise have been by car (Bigazzi & Wong, 2020; Bourne et al., 2020; Cairns et al., 2017; Fukushige et al., 2021).

Shared electric bicycles can enhance this effect. The need for docking stations and rebalancing services (i.e., the use of larger vehicles to reposition bicycles to avoid one-way trips that create shortages in some places and surpluses in others) increases the carbon emissions of electric bicycles per pkm compared with private electric bicycles. By renting out electric bicycles one trip at a time, however, bicycle-share systems can make electric bicycles affordable to a larger percentage of the public, further increasing the number of pkm that can be shifted to electric bicycles.

The adoption of electric bicycles reduces emissions of CO₂ and methane from cars by displacing pkm traveled via car. When electric bicycles replace a trip by a gasoline- or diesel-powered car, they also eliminate reliance on fossil fuels to complete that trip. Even if the electricity used to power electric bicycles comes from fossil fuels, those emissions are relatively small and could eventually be replaced with low-emission electricity through the deployment of renewables or similar technologies.

Astegiano, P., Fermi, F., & Martino, A. (2019). Investigating the impact of e-bikes on modal share and greenhouse emissions: A system dynamic approach. Transportation Research Procedia, 37, 163-170. Link to source: https://doi.org/10.1016/j.trpro.2018.12.179

Berjisian, E., & Bigazzi, A. (2019). Summarizing the impacts of electric bicycle adoption on vehicle travel, emissions, and physical activity. UBC REACT LAb. Link to source: https://civil-reactlab.sites.olt.ubc.ca/files/2019/07/BerjisianBigazzi_ImpactsofE-bikes_Report_July2019.pdf

Bigazzi, A., & Wong, K. (2020). Electric bicycle mode substitution for driving, public transit, conventional cycling, and walking. Transportation Research Part D: Transport and Environment, 85, 102412. Link to source: https://doi.org/10.1016/j.trd.2020.102412

Bourne, J. E., Cooper, A. R., Kelly, P., Kinnear, F. J., England, C., Leary, S., & Page, A. (2020). The impact of e-cycling on travel behaviour: A scoping review. Journal of Transport & Health, 19, 100910. Link to source: https://doi.org/10.1016/j.jth.2020.100910

Bucher, D., Buffat, R., Froemelt, A., & Raubal, M. (2019). Energy and greenhouse gas emission reduction potentials resulting from different commuter electric bicycle adoption scenarios in Switzerland. Renewable and Sustainable Energy Reviews, 114, 109298. Link to source: https://doi.org/10.1016/j.rser.2019.109298 

Cairns, S., Behrendt, F., Raffo, D., Beaumont, C., & Kiefer, C. (2017). Electrically-assisted bikes: Potential impacts on travel behaviour. Transportation Research Part A: Policy and Practice, 103, 327-342. Link to source: https://doi.org/10.1016/j.tra.2017.03.007

Carracedo, D., & Mostofi, H. (2022). Electric cargo bikes in urban areas: A new mobility option for private transportation. Transportation Research Interdisciplinary Perspectives, 16, 100705. Link to source: https://doi.org/10.1016/j.trip.2022.100705

Dekker, P. (2013). Electrification of road transport-An analysis of the economic performance of electric two-wheelers. Utrecht University. Link to source: https://studenttheses.uu.nl/bitstream/handle/20.500.12932/13022/Thesis%20P.W.K.%20Dekker%2012%20May%202013.pdf?sequence=1&isAllowed=y

eBicycles. (2025a). How much does an electric bike cost? E-bike price breakdown [2025]. Link to source: https://www.ebicycles.com/how-much-does-an-electric-bike-cost/ 

eBicycles. (2025b). Useful facts & stats of e-bikes [for 2025] + infographic. Link to source: https://www.ebicycles.com/ebike-facts-statistics/ 

Ebike Canada. (2025). The best electric bikes & scooters in canada for 2025. Ebike Canada. Link to source: https://ebikecanada.com/best-electric-bike-and-scooter/ 

Fishman, E., & Cherry, C. (2016). E-bikes in the Mainstream: Reviewing a Decade of Research. Transport Reviews, 36(1), 72-91. Link to source: https://doi.org/10.1080/01441647.2015.1069907

Fukushige, T., Fitch, D. T., & Handy, S. (2021). Factors influencing dock-less E-bike-share mode substitution: Evidence from Sacramento, California. Transportation Research Part D: Transport and Environment, 99, 102990. Link to source: https://doi.org/10.1016/j.trd.2021.102990

Galatoulas, N.-F., Genikomsakis, K. N., & Ioakimidis, C. S. (2020). Spatio-Temporal Trends of E-Bike Sharing System Deployment: A Review in Europe, North America and Asia. Sustainability, 12(11), Article 11. Link to source: https://doi.org/10.3390/su12114611

Gössling, S., Choi, A., Dekker, K., & Metzler, D. (2019). The social cost of automobility, cycling and walking in the European Union. Ecological Economics, 158, 65–74. Link to source: https://doi.org/10.1016/j.ecolecon.2018.12.016 

Guidon, S., Becker, H., Dediu, H., & Axhausen, K. W. (2018). Electric bicycle-sharing: A new competitor in the urban transportation market?: An empirical analysis of transaction data. Arbeitsberichte Verkehrs- Und Raumplanung, 1364. Link to source: https://doi.org/10.1016/j.ecolecon.2018.12.016 

Hanna, J. (2023). Bike Share Toronto 2023 business review. Link to source: https://www.toronto.ca/legdocs/mmis/2023/pa/bgrd/backgroundfile-240804.pdf 

Helton, J. (2025). Ride with power: The top electric bikes for 2025, as chosen by experts. Road & Track. Link to source: https://www.roadandtrack.com/gear/lifestyle/g46464030/best-electric-bikes/ 

Huang, Y., Jiang, L., Chen, H., Dave, K., & Parry, T. (2022). Comparative life cycle assessment of electric bikes for commuting in the UK. Transportation Research Part D: Transport and Environment, 105, 103213. Link to source: https://doi.org/10.1016/j.trd.2022.103213 

Innovation Origins. (2023). The booming rise of shared e-bikes in urban mobility. Link to source: https://innovationorigins.com/en/the-booming-rise-of-shared-e-bikes-in-urban-mobility/ 

International Transport Forum. (2020). Good to Go? Assessing the Environmental Performance of New Mobility (Corporate Partnership Board). OECD. Link to source: https://www.itf-oecd.org/sites/default/files/docs/environmental-performance-new-mobility.pdf

Jones, B. (2019). Electric Bike Maintenance Cost. BicycleVolt. Link to source: https://bicyclevolt.com/electric-bike-maintenance-cost/ 

Koning, M., & Conway, A. (2016). The good impacts of biking for goods: Lessons from Paris city. Case Studies on Transport Policy, 4(4), 259-268. Link to source: https://doi.org/10.1016/j.cstp.2016.08.007

Langford, B. C., Chen, J., & Cherry, C. R. (2015). Risky riding: Naturalistic methods comparing safety behavior from conventional bicycle riders and electric bike riders. Accident Analysis & Prevention, 82, 220-226. Link to source: https://doi.org/10.1016/j.aap.2015.05.016

Langford, B. C., Cherry, C. R., Bassett, D. R., Fitzhugh, E. C., & Dhakal, N. (2017). Comparing physical activity of pedal-assist electric bikes with walking and conventional bicycles. Journal of Transport & Health, 6, 463–473. Link to source: https://doi.org/10.1016/j.jth.2017.06.002

Li, Q., Fuerst, F., & Luca, D. (2023). Do shared E-bikes reduce urban carbon emissions? Journal of Transport Geography, 112, 103697. Link to source: https://doi.org/10.1016/j.jtrangeo.2023.103697

Luxe Digital. (2025). The best electric bikes: upgrade your commute for a sustainable ride. Luxe Digital. Link to source: https://luxe.digital/lifestyle/garage/best-electric-bikes/ 

Matasyan, A. (2015). Technical analysis and market study of electric bicycles. Link to source: https://upcommons.upc.edu/handle/2117/77272?locale-attribute=en 

Mellino, S., Petrillo, A., Cigolotti, V., Autorino, C., Jannelli, E., & Ulgiati, S. (2017). A Life Cycle Assessment of lithium battery and hydrogen-FC powered electric bicycles: Searching for cleaner solutions to urban mobility. International Journal of Hydrogen Energy, 42(3), 1830–1840. Link to source: https://doi.org/10.1016/j.ijhydene.2016.10.146 

Mordor Intelligence. (2022). Asia Pacific e-bike market (2017-2029). Link to source: https://www.mordorintelligence.com/industry-reports/asia-pacific-e-bike-market

N, A. (2023). Maintenance costs for an electric bike. Bike LVR. Link to source: https://bikelvr.com/bikes/e-bikes/maintenance-costs-for-an-electric-bike/ 

de Nazelle, A., Nieuwenhuijsen, M., Antó, J., Brauer, M., Briggs, D., Charlotte Braun-Fahrlander, C., Cavill, N., Cooper, A., Desqueyroux, H., Fruin, S., Hoek, G., Panis, L., Janssen, N., Jerrett, M., Joffe, M., Andersen, Z., van Kempen, E., Kingham, S., Kubesch, N., Leyden, K., Marshall, J., Matamala, J., Mellios, G., Mendez, M., Nassif, H., Ogilvie, D., Peiró, R., Pérez, K., Rabl, A., Ragettli, M., Rodríguez, D., Rojas, D., Ruiz, P., Sallis, J., Terwoert, J., Toussaint, J., Tuomisto, J., Zuurbier, M., & Lebret, E. (2011). Improving health through policies that promote active travel: A review of evidence to support integrated health impact assessment. Environment International, 37(4), 767-777. Link to source: https://doi.org/10.1016/j.envint.2011.02.003 

PBSC Urban Solutions. (2022). The Meddin Bike-sharing World Map Report 2022 edition. Link to source: https://bikesharingworldmap.com/reports/bswm_mid2022report.pdf

Pekow, C. (2024, April 1). E-bikes could cut smog, energy use and congestion globally—But will they? Mongabay Environmental News. Link to source: https://news.mongabay.com/2024/04/e-bikes-could-cut-smog-energy-use-and-congestion-globally-but-will-they/

Philips, I., Anable, J., & Chatterton, T. (2022). E-bikes and their capability to reduce car CO2 emissions. Transport Policy, 116, 11-23. Link to source: https://doi.org/10.1016/j.tranpol.2021.11.019

Platt, S. M., Haddad, I. E., Pieber, S. M., Huang, R.-J., Zardini, A. A., Clairotte, M., Suarez-Bertoa, R., Barmet, P., Pfaffenberger, L., Wolf, R., Slowik, J. G., Fuller, S. J., Kalberer, M., Chirico, R., Dommen, J., Astorga, C., Zimmermann, R., Marchand, N., Hellebust, S., … Prévôt, A. S. H. (2014). Two-stroke scooters are a dominant source of air pollution in many cities. Nature Communications, 5(1), 3749. Link to source: https://doi.org/10.1038/ncomms4749

Precedence Research. (2024). E-bike market poised for robust expansion | CAGR of 10.16%. Link to source: https://www.precedenceresearch.com/insights/e-bike-market 

Roberts, C. (2023). Diversity in passenger mobility: Where it went and how to bring it back. One Earth, 6(1), 11-13. Link to source: https://doi.org/10.1016/j.oneear.2022.12.008

Roberts, C. (2020). Into a headwind: Canadian cycle commuting and the growth of sustainable practices in hostile political contexts. Energy Research and Social Science, 70. Scopus. Link to source: https://doi.org/10.1016/j.erss.2020.101679

Rodriguez Mendez, Q., Fuss, S., Lück, S., & Creutzig, F. (2024). Assessing global urban CO2 removal. Nature Cities, 1(6), 413-423. Link to source: https://doi.org/10.1038/s44284-024-00069-x

Shi, Z., Wang, J., Liu, K., Liu, Y., & He, M. (2024). Exploring the usage efficiency of electric bike-sharing from a spatial–temporal perspective. Transportation Research Part D: Transport and Environment, 129, 104139. Link to source: https://doi.org/10.1016/j.trd.2024.104139 

So, A. (2024). Best electric bikes (2025): Hauling, commuting, mountain biking. WIRED. Link to source: https://www.wired.com/gallery/best-electric-bikes/ 

Stewart, D., & Ramachandran, K. (2022, March 31). E-bikes merge into the fast lane. Deloitte Insights. Link to source: https://www2.deloitte.com/us/en/insights/industry/technology/smart-micromobility-e-bikes.html

Strategic Market Research. (2024). E-bikes statistics and trends 2024. Link to source: https://www.strategicmarketresearch.com/blogs/e-bikes-statistics 

Summit Bike Share. (2023). Summit bike share end of year report 2023. Link to source: https://www.summitcountyutah.gov/2415/Summit-Bike-Share 

Teixeira, J. F., Silva, C., & Moura e Sá, F. (2021). Empirical evidence on the impacts of bikesharing: A literature review. Transport Reviews, 41(3), 329-351. Link to source: https://doi.org/10.1080/01441647.2020.1841328

The Freedonia Group. (2024). Global E-Bikes—Market Size, Market Share, Market Leaders, Demand Forecast, Sales, Company Profiles, Market Research, Industry Trends and Companies. The Freedonia Group. Link to source: https://www.freedoniagroup.com/industry-study/global-e-bikes

Thomas, A. (2022). Electric bicycles and cargo bikes—Tools for parents to keep on biking in auto-centric communities? Findings from a US metropolitan area. International Journal of Sustainable Transportation, 16(7), 637-646. Link to source: https://doi.org/10.1080/15568318.2021.1914787

Van Acker, V., & Witlox, F. (2010). Car ownership as a mediating variable in car travel behaviour research using a structural equation modelling approach to identify its dual relationship. Journal of Transport Geography, 18(1), 65-74. Link to source: https://doi.org/10.1016/j.jtrangeo.2009.05.006

Wamburu, J., Lee, S., Hajiesmaili, M. H., Irwin, D., & Shenoy, P. (2021). Ride Substitution Using Electric Bike Sharing: Feasibility, Cost, and Carbon Analysis. Proc. ACM Interact. Mob. Wearable Ubiquitous Technol., 5(1), 38:1-38:28. Link to source: https://doi.org/10.1145/3448081

WHO. (2022). Number of registered vehicles. Link to source: https://www.who.int/data/gho/data/indicators/indicator-details/GHO/number-of-registered-vehicles 

WHO. (2023). Despite notable progress, road safety remains urgent global issue. Link to source: https://www.who.int/news/item/13-12-2023-despite-notable-progress-road-safety-remains-urgent-global-issue

World Bank. (2024). World Development Indicators. Link to source: https://datacatalog.worldbank.org/search/dataset/0037712/World-Development-Indicators

Weiss, M., Dekker, P., Moro, A., Scholz, H., & Patel, M. K. (2015). On the electrification of road transportation – A review of the environmental, economic, and social performance of electric two-wheelers. Transportation Research Part D: Transport and Environment, 41, 348-366. Link to source: https://doi.org/10.1016/j.trd.2015.09.007

Yang, Y., Okonkwo, E. G., Huang, G., Xu, S., Sun, W., & He, Y. (2021). On the sustainability of lithium ion battery industry – A review and perspective. Energy Storage Materials, 36, 186-212. Link to source: https://doi.org/10.1016/j.ensm.2020.12.019

Credits

Lead Fellows

  • Cameron Roberts, Ph.D.

  • Heather Jones, Ph.D.

Contributors

  • Ruthie Burrows, Ph.D.

  • James Gerber, Ph.D.

  • Yusuf Jameel, Ph.D.

  • Daniel Jasper

  • Heather McDiarmid, Ph.D.

  • Alex Sweeney

Internal Reviewers

  • Aiyana Bodi

  • Hannah Henkin

  • Ted Otte

  • Amanda D. Smith, Ph.D.

Effectiveness

Per 1,000 private electric bicycles, approximately 110.5 t CO₂‑eq/yr is offset by displacing trips taken by higher-emission transportation modes such as cars and public transit (Table 1a). 

Per 1,000 shared electric bicycles, approximately 14.44 t CO₂‑eq/yr is offset (Table 1b). This lower value is due to the additional emissions produced in the operation of a shared electric-bicycle system (e.g., due to the need to reposition bicycles after they accumulate in some locations while becoming depleted in others). Additionally, other modes of transportation are shifted to shared electric bicycles at different rates than privately owned electric bicycles – notably shifted less from car travel. These factors limit the total GHG emissions reduced per shared electric bicycle.

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Table 1. Effectiveness at reducing emissions.

Unit: t CO₂‑eq /1,000 electric bicycles/yr, 100-yr basis

25th percentile 55.87
Mean 136.1
Median (50th percentile) 110.5
75th percentile 220.5

Unit: t CO₂‑eq /1,000 electric bicycles/yr, 100-yr basis

25th percentile 1.415
Mean 14.62
Median (50th percentile) 14.44
75th percentile 34.31
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Cost

Electric bicycles vary significantly in cost, but generally are more expensive than traditional bicycles due to the cost of batteries, motors, and other electronic components, as well as the need for more durable mechanical components. 

Private electric bicycles cost about US$2,700, plus another few hundred dollars per year in maintenance costs. All told, assuming a 10-year lifespan, electric bicycles cost about US$600/yr to operate . The average privately owned electric bicycle is ridden 2,400 km/yr; since 28.67% of that distance is shifted from car trips, electric bicycles displace approximately 688 pkm/yr traveled by car. Car travel costs US$0.53/pkm while electric bicycle travel costs US$0.25/pkm, meaning every pkm traveled via electric bicycle saves US$0.28. Multiplied over 688 pkm/yr, this translates to every electric bicycle saving its owner approximately US$193/yr in avoided car trips (Bucher et al., 2019; Carracedo & Mostofi, 2022; eBicycles, 2025a; Ebike Canada, 2025; Gössling et al., 2019; Helton, 2025; Huang et al., 2022; International Transport Forum, 2020; Jones, 2019; Luxe Digital, 2025; Mellino et al., 2017; N, 2023; So, 2024; Weiss et al., 2015).

Most of the costs of riding an electric bicycle are up-front costs. As a result, electric bicycle owners who shift more trips from a car onto their electric bicycle will significantly increase their savings. Privately owned electric bicycles save US$1,748 for every t CO₂‑eq they avoid (Table 2a).

Shared electric bicycles are more expensive to the system provider than privately owned electric bicycles due to greater needs for infrastructure, maintenance, operating expenses, and services, such as rebalancing. Shared electric bicycles cost US$2.42/pkm and displace an average of 156 pkm/yr from car trips per bicycle. The same distance traveled by car costs US$83, meaning that shared electric bicycles cost an additional US$295/yr compared to traveling the same distance by car (Gössling et al., 2019; Guidon et al., 2018; Hanna, 2023; Matasyan, 2015; Summit Bike Share, 2023). Shared electric bicycles cost US$22,860/t CO₂‑eq avoided due to their higher costs, higher emissions, and the lower chance that riders on shared electric bicycles would otherwise have been traveling by car (Table 2b).

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Table 2. Cost per climate impact.

Unit: US$ (2023) per t CO₂‑eq , 100-year basis

Median (50th percentile) –1,748

Unit: US$ (2023) per t CO₂‑eq , 100-year basis

Median (50th percentile) 22,860

*Cost to the provider of the system, not the user

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Learning Curve

Learning rates for electric bicycles are often negative (i.e., prices increase with cumulative production). This is largely because electric bicycle batteries have grown larger over time, causing the bicycles to become more expensive (Dekker, 2013; Weiss et al., 2015). The learning rate per electric bicycle ranges from 15% to –43% (Table 3a). This range has improved the general value proposition of electric bicycles, however, since larger batteries enable electric bicycles to go further and faster than before.

To compensate for this, it is useful to calculate the learning rate per kWh battery capacity rather than per bicycle. On this measure, Dekker (2013) calculates a learning rate of 7.9% cost reduction per kWh of electric bicycle battery capacity for every doubling of cumulative production (Table 3b).

These estimates are based on analyses published in 2013 and 2015, respectively, and therefore do not take into account more recent advances in electric bicycle production. More up-to-date research on electric bicycle learning rates is needed to inform future assessments on this topic.

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Table 3. Learning rate: drop in cost per doubling of cumulative electric bicycle production.*

Unit: %

25th percentile –43.50
Mean –26.86
Median (50th percentile) –36.00
75th percentile 15

* These data are from 2013 and 2015, due to a lack of available research on this topic.

Unit: %

Median (50th percentile) 7.9

* These data are from 2013 and 2015, due to a lack of available research on this topic.

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Speed of Action

Speed of action refers to how quickly a climate solution physically affects the atmosphere after it is deployed. This is different from speed of deployment, which is the pace at which solutions are adopted.

At Project Drawdown, we define the speed of action for each climate solution as emergency brake, gradual, or delayed.

Mobilize Electric Bicycles is a GRADUAL climate solution. It has a steady, linear impact on the atmosphere. The cumulative effect over time builds as a straight line.

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Caveats

Electric bicycles do not only compete with cars for the total passenger transport demand; a given electric bicycle trip might also substitute for public transit. This can sometimes still be beneficial since, as electric bicycles often have lower per-kilometer emissions than public transit vehicles (International Transport Forum, 2020). However, an electric bicycle trip might also substitute for a conventional bicycle trip or for a pedestrian journey, in which case electric bicycle usage would actually increase emissions. Finally, some electric bicycle trips are new journeys, meaning that they would not occur at all if the traveler did not have an electric bicycle, which also increases emissions (Astegiano et al., 2019; Berjisian & Bigazzi, 2019; Bourne et al., 2020; Cairns et al., 2017; Dekker, 2013).

Generally speaking however, electric bicycles still shift enough passenger car trips to make up for this effect, although the scale can be more marginal with shared electric bicycle systems. However, electric bicycles are more likely to substitute more for whichever forms of transportation their users were already using previously (Wamburu et al., 2021). This means that wider adoption of electric bicycles in car-dependent North American suburbs, for example, will have a much clearer and more beneficial climate impact than in a dense, pedestrianized European city center, or in a low-income country where most people do not have access to a car (although in these contexts electric bicycles could still produce major social and economic benefits).

Our estimates of the total adoption ceiling potential of electric bicycles (described in the Adoption section) are based on the ratio of adoption between electric bicycles and cars, on the grounds that each electric bicycle avoids some amount of car travel. However, the relationship is not necessarily quite so simple. Car trips with passengers might require more than one electric bicycle trip to replace them (unless the passengers are children, who can be carried as passengers on electric bicycles). On the other side of the equation, some households own more than one car per person. Having more than one electric bicycle per car would therefore not meaningfully reduce car trips. Lastly, our approach of tracking electric bicycle adoption in relation to car ownership neglects people whose use of an electric bicycle enables them to avoid owning a car at all. Estimates of adoption should be taken as rough guesses, rather than authoritative forecasts.

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Current Adoption

Private electric bicycles have experienced significant growth since 2015. We estimate there are approximately 278 million private electric bicycles in use in the world today (Table 4a). 

Data on this subject typically include throttle-assisted electric bicycles, e-scooter/trotinettes, and sometimes mopeds and motorcycles; these are not included in this solution. Data from China, the highest adopter of electric bicycles, does not usually distinguish between types of electric two-wheelers. For this reason, we used more conservative estimates, preferring to understate adoption than overstate it. We used several global estimates, data on electric bicycle sales in Canada, the United States, and Europe, and stock estimates from the Asia-Pacific region (eBicycles, 2025b; Mordor Intelligence, 2022; Precedence Research, 2024; Stewart & Ramachandran, 2022; Strategic Market Research, 2024; The Freedonia Group, 2024). To convert from European and American sales data to stocks data, we assumed that all electric bicycles sold over the past 10 years (the lifespan of an electric bicycle) are still in use today. We then calculated the number of electric bicycles per 1,000 people in each of the three regions, used those three values to calculate a population-weighted global mean adoption rate, and multiplied the result by the number of residents of high- and upper-middle income countries worldwide (where we assume most electric bicycle adoption takes place). This calculation provided a global estimate.

Shared electric bicycle schemes now exist in many cities around the world, with at least 2 million shared electric bicycles currently in use as part of electric bicycle sharing systems (Table 4b; eBicycles, 2025b; Innovation Origins, 2023; PBSC Urban Solutions, 2022; Strategic Market Research, 2024). This is a conservative estimate because research published in a reputable academic journal claimed that China has 8.7 million shared electric bicycles in 2022 (Shi et al., 2024). 

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Table 4. Current (2024) adoption level.

Unit: 1,000 electric bicycles

Population-weighted mean 277600

Unit: 1,000 electric bicycles

Population-weighted mean 2000
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Adoption Trend

Private electric bicycles are being adopted at a rate of about 37 million new bicycles every year (eBicycles, 2025b; Mordor Intelligence, 2022; Precedence Research, 2024; Stewart & Ramachandran, 2022; Strategic Market Research, 2024; The Freedonia Group, 2024; see Table 5a). Electric bicycles are also attracting interest from consumers who do not normally ride bicycles, including people in rural areas (Philips et al., 2022) and members of vulnerable groups, such as the elderly. 

Shared electric bicycles are being added to cities at a rate of approximately 413,000/yr (eBicycles, 2025b; Innovation Origins, 2023; PBSC Urban Solutions, 2022; Strategic Market Research, 2024; see Table 5b). Cities and private companies are adding shared electric bicycle systems at a rate of around 30/yr (Galatoulas et al., 2020). Based on these data, we calculate a 37.97% compounding annual growth rate in electric bicycle sharing system installations around the world. 

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Table 5. 2023–2024 adoption trend.

Unit: 1,000 electric bicycles/yr

25th percentile 34000
Population-weighted mean 37330
Median (50th percentile) 38000
75th percentile 40000

Unit: 1,000 electric bicycles/yr

Median (50th percentile) 412.5
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Adoption Ceiling

Because we model electric bicycles as a solution primarily due to their ability to shift travel from fossil fuel–powered cars, we estimate adoption by reference to the ratio of electric bicycles to cars. This does not mean that people without access to a car will not use electric bicycles; it means that they are not shifting their pkm from fossil fuel–powered cars and therefore are not included in the calculations of shifting from car to electric bicycle. 

Private electric bicycles’ adoption ceiling (Table 6a) would be approximately 2 billion around the world: one for every car (World Health Organization, 2021). This would mean that every motorist has an electric bicycle as a ready alternative to a car.

Shared electric bicycles’ adoption ceiling can be measured similarly, except that we assume these systems are only viable in cities. Therefore, we set the maximum adoption ceiling of shared electric bicycles to be 1.3 billion (Table 6b) – the number of cars in cities around the world. we estimated by multiplying the global urban population (4.45 billion) by the global average car registrations per 1,000 people (286.2) (World Health Organization, 2021; World Bank, 2024).

This upper-bound scenario faces many of the same caveats as the upper-bound scenario for the Improve Nonmotorized Transportation solution. It would require a revolution in support for electric bicycles: new infrastructure, new traffic laws, a substantial increase in electric battery production capacity, and major changes to built environments, including increases in population and land-use density to make more journeys feasible by electric bicycle. However, this scenario would require less dramatic change than a similar upper-bound scenario for the Improve Nonmotorized Transportation solution because electric bicycles go faster, have higher carrying capacities, can travel longer distances, and are easier to use than nonmotorized travel modes (Weiss et al., 2015).

A limitation of this analysis is that one electric bicycle per car does not necessarily correspond to one electric bicycle per person traveling in a car. For example, it is possible that replacing one car trip with electric bicycles would result in multiple electric bicycle trips in order to carry multiple passengers. Our estimates should therefore be seen as approximate. 

It is also possible for total electric bicycle adoption and usage to exceed car use (i.e., electric bicycles also replace other modes of transportation or generate new trips). We do not consider this scenario in our adoption ceiling because additional adoption above car adoption would not produce a major climate benefit.

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Table 6. Adoption ceiling.

Unit: 1,000 electric bicycles

Adoption ceiling 2022000

Unit: 1,000 electric bicycles

Adoption ceiling 1273000
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Achievable Adoption

Private electric bicycles are currently in use across the Asia-Pacific region at a rate of approximately 0.07 electric bicycles for every car. A low achievable adoption rate might see every country in the world achieve this same ratio, which would lead to a global electric bicycle fleet of 421 million (Table 7a). For a higher rate of adoption, we posit one electric bicycle in use for every two cars. This would see just more than 1 billion electric bicycles in use worldwide.

Using the median and 75th percentile of the ratio of shared electric bicycles to cars (for which we have data) as the rate of adoption seen in every city in the world leads to 22 to 69 million shared electric bicycles in cities worldwide (Table 7b).

Note: We based these estimates on electric bicycles per car rather than electric bicycles per person because the climate impact of electric bicycle adoption in a given place depends on the availability of cars to replace. 

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Table 7. Range of achievable adoption levels.

Unit: 1,000 electric bicycles

Current adoption 277600
Achievable – low 421300
Achievable – high 1011000
Adoption ceiling 2022000

Unit: 1,000 electric bicycles

Current adoption 2000
Achievable – low 22010
Achievable – high 69260
Adoption ceiling 1273000
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If every motorist had an electric bicycle they used to replace at least some car trips, it would mitigate 224 Mt CO₂‑eq/yr – equal to the total global carbon emissions produced by cars, minus the emissions that would be produced due to electric bicycles traveling the same distance. If there were one electric bicycle for every two cars, it would avoid 117 Mt CO₂‑eq/yr. And if global electric bicycle adoption reached the rate currently seen in the Asia-Pacific region (China, India, Japan, South Korea, Australia, and New Zealand), it would avoid 47 Mt CO₂‑eq/yr (Table 8a).

Our Achievable – Low scenario of 22 million shared electric bicycles in cities worldwide would save 284 kt CO₂‑eq/yr (Table 8b). Our Achievable – High scenario of 69.3 million shared electric bicycles worldwide would save 895 kt CO₂‑eq/yr. The maximum possible shared electric bicycle deployment would save approximately 16.6 Mt CO₂‑eq/yr.

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Table 8. Climate impact at different levels of adoption.

Unit: Gt CO₂-eq/yr, 100-yr basis

Current adoption 0.0307
Achievable – low 0.0466
Achievable – high 0.1117
Adoption ceiling 0.2235

Unit: Gt CO₂-eq/yr, 100-yr basis

Current adoption 0.00002584
Achievable – low 0.0002844
Achievable – high 0.0008949
Adoption ceiling 0.01645
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Additional Benefits

Income and Work

In addition to being cheaper than car travel, electric bicycles allow people to travel farther and faster than they could on foot, on a conventional bicycle, or (often) on public transit. Time savings from quick, longer trips, reduced traffic congestion, and money savings provide an economic benefit (Bourne, 2020). 

Health

Electric bicycles provide quality-of-life benefits for some people who use them (Bourne, 2020; Carracedo & Mostofi, 2022; Teixeira et al., 2022; Thomas, 2022). Electric assistance reduces the physical fitness and other health benefits of cycling. However, electric bicycles still require pedaling, and studies show that this level of effort required can still have substantial health benefits (Berjisian & Bigazzii, 2019; Langford et al., 2017). Electric bicycles can also enable people to cycle who might not otherwise be able to (Bourne et al., 2020). Additionally, electric bicycles can reduce total car traffic, which could reduce the risk of injury and death from car crashes, which kill 1.2 million people annually (WHO, 2023). Similarly, electric bicycles can reduce health impacts of traffic noise (de Nazelle et al., 2011).

Air Quality

The fossil fuel–powered vehicles most similar to electric bicycles (motorcycles, scooters, etc.) are extremely polluting (Platt et al., 2014). Substituting electric bicycles for these can substantially reduce air pollution.

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Risks

Electric bicycles pose some safety concerns, centering on an ongoing debate over whether electric cyclists ride more recklessly than other cyclists (Fishman & Cherry, 2016; Langford et al., 2015). While electric bicycles have a lower injury rate than conventional bicycles, when injuries do happen during electric bicycle travel the health consequences tend to be more severe due to the higher speed (Berjisian & Bigazzi, 2019). There may also be risks related to the bicycles’ lithium-ion batteries catching fire. Strong regulations can minimize this risk (Pekow, 2024). Improved infrastructure, such as separated bike lanes and paths, can also reduce the safety risks associated with electric bicycles (Roberts, 2020).

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Interactions with Other Solutions

Reinforcing

Electric bicycles can complement other forms of low-carbon mobility, especially those that reduce dependence on private cars. People who rely on public transit, conventional travel, pedestrian travel, carpools, or other sustainable modes of transportation for some kinds of trips can use electric bicycles to fill in some of the gaps in their personal transportation arrangements (Roberts, 2023). For public transit in particular, electric bicycles can play an important last-mile role, enabling transit riders to more easily access stops. This is important because research suggests that the key to a low-carbon mobility system is to enable people to live high-quality lives without owning cars (Van Acker & Witlox, 2010).

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Competing

Electric bicycles compete with electric and hybrid cars and electric scooters and motorcycles for adoption.

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Dashboard

Solution Basics

1,000 electric bicycles

t CO₂-eq (100-yr)/unit/yr
055.87110.5
units
Current 277,600 0421,3001.01×10⁶
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 0.031 0.0470.112
US$ per t CO₂-eq
-1,748
Gradual

CO₂, CH₄, N₂O, BC

Solution Basics

1,000 electric bicycles

t CO₂-eq (100-yr)/unit/yr
01.41514.44
units
Current 2,000 022,01069,260
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 2.583×10⁻⁵ 2.843×10⁻⁴8.949×10⁻⁴
US$ per t CO₂-eq
22,860
Gradual

CO₂, CH₄, N₂O, BC

Trade-offs

If an electric bicycle replaces primarily car trips, it provides an unambiguous climate benefit. If it replaces public transit, the size of the benefit will depend on the specifics of the public transit system it replaces. If it replaces pedestrian trips or conventional cycling trips, or generates new trips, the net climate benefit is negative. Travel survey data suggest that electric bicycles replace enough car journeys to more than offset any journeys by the more sustainable modes of transportation they replace (Bigazzi & Wong, 2020; Bourne et al., 2020; Cairns et al., 2017; Fukushige et al., 2021). However, electric bicycles in cities that already have very low-carbon mobility systems, or in lower-income countries where car ownership is rare, might have a net negative climate impact. 

Electric bicycles also require batteries, the production and disposal of which generates pollution (Yang et al., 2021). However, electric bicycles require much less battery capacity than many other electrification technologies, such as electric vehicles (Weiss et al., 2015).

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Mt CO2–eq/yr
0–4
4–8
8–12
12–16
16–20
> 20
No data

Annual road transportation emissions, 2024

Cars are the largest source of road transportation vehicle emissions, which are shown here for urban areas.

Kott, T., Foster, K., Villafane-Delgado, M., Loschen, W., Sicurello, P., Ghebreselassie, M., Reilly, E., and Hughes, M. (2024). Transportation sector - Global road emissions [Data set]. The Johns Hopkins University Applied Physics Laboratory (JHU/APL), Climate TRACE Emissions Inventory. Retrieved March 12, 2025 from Link to source: https://climatetrace.org

Mt CO2–eq/yr
0–4
4–8
8–12
12–16
16–20
> 20
No data

Annual road transportation emissions, 2024

Cars are the largest source of road transportation vehicle emissions, which are shown here for urban areas.

Kott, T., Foster, K., Villafane-Delgado, M., Loschen, W., Sicurello, P., Ghebreselassie, M., Reilly, E., and Hughes, M. (2024). Transportation sector - Global road emissions [Data set]. The Johns Hopkins University Applied Physics Laboratory (JHU/APL), Climate TRACE Emissions Inventory. Retrieved March 12, 2025 from Link to source: https://climatetrace.org

Maps Introduction

Electric bicycle effectiveness in mitigating climate change varies by region, depending on the carbon intensity of the charging electricity, the extent to which they replace higher-emission travel (such as cars, motorcycles, or taxis), and the need and type of vehicle used for rebalancing shared electric bicycles (International Transport Forum, 2020). They are most effective in areas with cleaner electricity grids and where they can substitute for cars. 

Since electric bicycles are more effective when replacing cars, this means that wider adoption of electric bicycles in car-dependent regions, such as North American suburbs, will have a much more significant climate impact than in a dense, pedestrianized European city center or in a low-income country where most people do not have access to a car (although in these contexts electric bicycles could still produce significant social and economic benefits) (Wamburu et al., 2021).

Socioeconomic and infrastructural factors play a major role in adoption. These include upfront costs of private electric bicycles, availability and affordability of shared electric bicycles, supportive cycling infrastructure, and policies such as subsidies or rebates. In many countries, electric bicycles increase the accessibility of nonmotorized transport for older adults, people with disabilities, and those commuting longer distances or in hilly areas by reducing physical effort (Bourne et al., 2020).

Future geographic targets for scaling adoption with strong climate and equity outcomes include South and Southeast Asian cities (e.g., Dhaka, Jakarta, Ho Chi Minh City) with high trip density, short trip lengths, and growing pollution concerns, all of which make them ideal for adoption. Sub-Saharan African cities (e.g., Kampala, Accra) where electric bicycles could complement or replace informal motorcycle taxis, reducing emissions and improving affordability and safety, are also important targets. North America has potential as both private and shared programs are beginning to expand in urban areas, helped by municipal investment and rising consumer interest.

Action Word
Mobilize
Solution Title
Electric Bicycles
Classification
Highly Recommended
Lawmakers and Policymakers
  • Establish policies that reduce the associated time, distance, risk, and risk perception for users and potential users.
  • Provide financial incentives such as tax breaks, subsidies, or grants for electric bicycle production and purchases.
  • Use targeted financial incentives to assist low-income communities in purchasing electric bicycles and to incentivize manufacturers to produce more affordable options.
  • Develop local bicycle and charging infrastructure, such as building physically separated bicycle lanes.
  • Have locking posts installed in public spaces that can accommodate electric bicycles.
  • Increase maintenance of bicycle infrastructure, such as path clearing.
  • Create international standards for the manufacturing and classification of electric bicycles.
  • Transition fossil fuel electricity production to renewables while promoting the transition to electric bicycles.
  • Offer one-stop shops for information on electric and non-motorized bicycles, including demonstrations and educational resources on cost savings, environmental impact, and maintenance.
  • Set regulations for sustainable use of electric bicycle batteries and improve recycling infrastructure.
  • Join international efforts to promote and ensure supply chain environmental and human rights standards – particularly, for the production of batteries.
  • Create, support, or join partnerships that offer information, training, and general support for electric and non-motorized bicycle adoption.

Further information:

Practitioners
  • Share your experiences with electric bicycles, providing tips and reasons for choosing this mode of transportation..
  • Participate in local bike groups, public events, and volunteer opportunities.
  • Advocate tor local officials for infrastructure improvements and note specific locations where improvements can be made.
  • Encourage local businesses to create employee incentives.
  • Provide information and resources to help individuals, households, and business owners take advantage of state and local tax benefits or rebates for electric bicycle purchases.

Further information:

Business Leaders
  • Advocate for better cycling infrastructure and sharing systems with city officials.
  • Educate customers about local bicycle infrastructure and encourage them to engage public officials.
  • Offer employees who agree to forgo a free parking space the annualized cash value or cost of that parking space as a salary increase.
  • Provide battery recycling services.
  • Offer free classes for electric bicycle maintenance and repair; educate employees about what they should know before purchasing an electric bicycle.
  •  
  • Install locking posts, parking, and security for electric bicycles.
  • Provide adequate onsite storage and charging, create educational materials on best practices for commuting, and offer pre-tax commuter benefits to encourage employee ridership.
  • Encourage electric bicycle use in company fleets by replacing or supplementing vehicles for local deliveries or transiting between office locations.
  • Incorporate electric bicycle programs into company sustainability and emission reduction initiatives;communicate how those programs support broader company goals. 

Further information:

Nonprofit Leaders
  • Inform the public about the health and environmental benefits of electric bicycles.
  • Educate the public on government incentives for electric bicycles and how to take advantage of them.
  • Provide impartial information on local electric bicycle infrastructure, best practices for maintenance, and factors to consider when renting or buying electric bicycles.
  • Advocate to policymakers for improved infrastructure and incentives.
  • Administer public initiatives such as ride-share or buy-back programs.

Further information:

Investors
  • Invest in electric bicycle companies and start-ups, including battery and component suppliers.
  • Explore investment opportunities that address supply chain issues such as battery suppliers and maintenance providers.
  • Invest in companies conducting R&D to improve electric bicycle performance, decrease the need for materials, and reduce maintenance costs.
  • Invest in public or private electric bicycle sharing systems.
  • Finance electric bicycle purchases via low-interest loans.
  • Invest in charging infrastructure for electric bicycles.

Further information:

Philanthropists and International Aid Agencies
  • Award grants to local organizations advocating for improved bicycle infrastructure and services.
  • Support access through the distribution or discounting of electric bicycles and help educate community members about relevant incentives.
  • Strengthen local infrastructure and build local capacity for infrastructure design and construction.
  • Ensure that donated bicycles are appropriate for the environment and that recipients have access to maintenance and supplies.
  • Sponsor community engagement programs such as group bike rides or free maintenance classes.
  • Assist with local policy design.

Further information:

Thought Leaders
  • Lead by example and use an electric bicycle as a regular means of transport.
  • Focus public messages on key decision factors for commuters, such as associated health and fitness benefits, climate and environmental benefits, weather forecasts, and traffic information.
  • Showcase principles of safe urban design and highlight dangerous areas.
  • Share detailed information on local bike routes, general electric bicycle maintenance tips, items to consider when purchasing a bike, and related educational information.
  • Collaborate with schools to teach bicycle instruction, including safe riding habits and maintenance tips.

Further information:

Technologists and Researchers
  • Examine and improve elements of battery design and maintenance.
  • Improve electric bicycle infrastructure design.
  • Improve circularity, repairability, and ease of disassembly for electric bicycles.
  • Increase the physical carrying capacities for users of electric bicycles to facilitate shopping and transporting children, pets, and materials.
  • Improve other variables that increase the convenience, safety, and comfort levels of nonmotorized transportation.

Further information:

Communities, Households, and Individuals
  • Share your experiences with electric bicycles; provide tips and reasons for choosing this mode of transportation.
  • Participate in local bike groups, public events, and volunteer opportunities.
  • Advocate to employers and local businesses to provide incentives for electric bicycle usage and help start local initiatives.
  • Advocate to local officials for infrastructure improvements and note specific locations where improvements can be made.
  • Encourage local businesses to create employee incentives.

Further information:

Sources
Evidence Base

Consensus of effectiveness in reducing emissions: High

When people purchase electric bicycles, they tend to use them often, with many of the trips they take on electric bicycles replacing trips that would otherwise have been taken via private car (Bigazzi & Wong, 2020; Bourne et al., 2020; Cairns et al., 2017; Fukushige et al., 2021). The evidence is similarly conclusive regarding the ability of shared electric bicycles to replace a large number of car trips. However, evidence regarding the carbon benefits of shared electric bicycles is more mixed due to the additional emissions required to run a shared electric-bicycle system.

Berjiisian and Bigazzi (2019) reviewed much of the literature on electric bicycles. and found that electric bicycle trips are shifted from car trips (44%) and transit trips (12%) providing significant emissions benefits. Other net benefits include less travel by cars, lower GHG emissions and more physical activity. “E-bike adoption is expected to provide net benefits in the forms of reduced motor vehicle travel, reduced greenhouse gas emissions, and increased physical activity. A little more than half of e-bike trips are expected to shift travel from motor vehicles (44% car trips and 12% transit trips), which is sufficient to provide significant emissions benefits.”

Weiss et al. (2015) surveyed evidence of the economic, social, and environmental impacts of electric bicycles. They found that electric bicycles are more efficient and less polluting than cars. They reduce exposure to pollution as their environmental impacts come mainly from being produced and the electricity that they use, both of which are usually outside of urban areas.

Philips et al. (2022) investigated the potential for electric bicycles to replace car trips in the UK. Their geospatial model provided a good indication of what might be possible in other places and showed that electric bicycles have considerable potential in rural areas as well as urban ones. 

Li et al. (2023) reported that based on the mix of mode share replaced, shared electric bicycle trips decreased carbon emissions by 108–120 g/km carbon emissions than fossil fuel-powered cars per kilometer.”

This research is biased toward high-income countries. While there is substantial research on electric bicycles in China, that country often considers e-scooters (which do not have pedals) and throttle-assisted electric bikes as interchangeable with pedelecs electric bicycles. This made it hard to include Chinese research in our analysis. We recognize this limited geographic scope creates bias, and hope this work inspires research harmonization and data sharing on this topic in underrepresented regions in the future.

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Updated Date

Enhance Public Transit

Submitted by Drawdown Admin on
Sector
Transportation
Mode
Cut Emissions
Cluster
Shift to Alternatives
Image
Train with city in the distance
Coming Soon
Off
Summary

We define the Enhance Public Transit solution as increasing the use of any form of passenger transportation that uses publicly available vehicles (e.g., buses, streetcars, subways, commuter trains, and ferries) operating along fixed routes. It does not include increasing the use of publicly available forms of transportation without fixed routes, such as taxis, except when these transport options supplement a larger public transit system (for example, to help passengers with disabilities). It also does not include increasing the use of vehicles traveling over long distances, such as intercity trains, intercity buses, or aircraft. The cost per climate unit is the cost to the transit provider, not the passenger.

Income & work,Health,Equality
Nature protection,Air quality
Description for Social and Search
Enhance Public Transit is a Highly Recommended climate solution. It not only reduces GHG emissions, but also can ease congestion, support compact development, and reduce the need for private vehicles.
Overview

Public transit vehicles are far more fuel-efficient – and thus less GHG-intensive – on a per-pkm basis than fossil fuel–powered cars. Diesel-powered buses emit fewer GHGs/pkm than cars because of their much higher occupancy. Electric buses further reduce GHG emissions (Bloomberg New Energy Finance, 2018), as do forms of public transit that already run on electricity. Finally, a fleet of large, centralized public transit vehicles operating along fixed routes is usually easier to electrify than a fleet of fossil fuel–powered cars. 

Enhancing public transit to reduce emissions from transportation relies on two processes. First is increasing the modal share of existing public transit networks by encouraging people to travel by public transit rather than car. This requires building new public transit capacity while also overcoming political, sociocultural, economic, and technical hurdles. Second is improving the emissions performance of public transit networks through electrification and efficiency improvements. We accommodate the latter in this solution by assuming that all shifted trips to buses are electric buses.

These two processes are linked in complex ways. For example, construction of the new public transit networks needed to accommodate additional demand creates an opportunity to install low-carbon vehicles and infrastructures, and bringing additional passengers onto an underused public transit network generates close to zero additional GHG emissions. However, since these complexities are difficult to calculate, we assume that all increases in public transit ridership are supported by a linear increase in capacity.

Buses, trains, streetcars, subways, and other public-transit vehicles predate cars. During the 19th century, most cities developed complex and efficient networks of streetcars and rail that carried large numbers of passengers (Norton, 2011; Schrag, 2000). As a result, it’s clear that a good public transit network can provide for the basic mobility needs of most people, and can therefore substitute for most – if not all – transportation that fossil fuel–powered cars currently provide. Today, public transit networks worldwide already collectively deliver trillions of pkm, not only in big cities but also in small towns and rural areas. 

We identified several different types of public transit:

Buses

Low-capacity vehicles running on rubber tires on roads. Buses in the baseline are a mix of diesel and electric. For the purposes of this solution, we assume that all buses serving shifted trips are electric.

Trams or streetcars

Mid-capacity vehicles running on steel rails that for at least part of their routes run on roads with traffic, rather than in a dedicated rail corridor or tunnel.

Metros, subways, or light rail

High-capacity urban train systems using their own dedicated right-of-way that may or may not be underground.

Commuter rail

Large trains running mostly on the surface designed to bring large numbers of commuters from the suburbs into the core of a city that often overlap with regional or intercity rail.

Other modes

Ferries, cable cars, funiculars, and other forms of public transit that generally play a marginal role.

We assessed all modes together rather than individually because public transit relies on the interactions among different vehicles to maximize the reach, speed, and efficiency of the system. Public transit reduces emissions of CO₂,  methane, and nitrous oxide to the atmosphere by replacing fuel-powered cars, which emit these gases from their tailpipes. Some diesel-powered buses in regions that have low quality diesel emit black carbon. The black carbon global annual total emissions from transportation is negligible compared with carbon emissions and is therefore not quantified in our study. 

American Public Transit Association. (2020). Economic impact of public transportation investment – American Public Transportation Association. Link to source: https://www.apta.com/research-technical-resources/research-reports/economic-impact-of-public-transportation-investment/ 

American Public Transit Association. (2021). National Transit Database Tables. American Public Transportation Association. Link to source: https://www.apta.com/research-technical-resources/transit-statistics/ntd-data-tables/

Beaudoin, J., Farzin, Y. H., & Lin Lawell, C.-Y. C. (2015). Public transit investment and sustainable transportation: A review of studies of transit’s impact on traffic congestion and air quality. Research in Transportation Economics, 52, 15–22. Link to source: https://doi.org/10.1016/j.retrec.2015.10.004 

Bloomberg New Energy Finance. (2018). Electric buses in cities: Driving towards cleaner air and lower CO2. Link to source: https://about.bnef.com/insights/clean-transport/electric-buses-cities-driving-towards-cleaner-air-lower-co2/

Börjesson, M., Fung, C. M., & Proost, S. (2020). How rural is too rural for transit? Optimal transit subsidies and supply in rural areas. Journal of Transport Geography, 88, 102859. Link to source: https://doi.org/10.1016/j.jtrangeo.2020.102859

Borck, R. (2019). Public transport and urban pollution. Regional Science and Urban Economics, 77, 356–366. Link to source: https://doi.org/10.1016/j.regsciurbeco.2019.06.005

Brown, A. E. (2017). Car-less or car-free? Socioeconomic and mobility differences among zero-car households. Transport Policy, 60, 152–159. Link to source: https://doi.org/10.1016/j.tranpol.2017.09.016

Brunner, H., Hirz, M., Hirschberg, W., & Fallast, K. (2018). Evaluation of various means of transport for urban areas. Energy, Sustainability and Society, 8(1), 9. Link to source: https://doi.org/10.1186/s13705-018-0149-0

Christensen, L., & Vázquez, N. S. (2013). Post-harmonised European National Travel Surveys. Proceedings from the Annual Transport Conference at Aalborg University, 20(1), Article 1. Link to source: https://doi.org/10.5278/ojs.td.v1i1.5701

Department for Transport. (2024). Transport Statistics Finder: Interactive Dashboard. Department for Transport. Link to source: https://app.powerbi.com/view?r=eyJrIjoiMGE2YTQ5YTMtMDkwNC00MjBmLWFkNjUtMjBjZjUzZWU0ZjNmIiwidCI6IjI4Yjc4MmZiLTQxZTEtNDhlYS1iZmMzLWFkNzU1OGNlNzEzNiIsImMiOjh9

Ecke, L. (2023). German Mobility Panel—Startseite (KIT). Lisa Ecke. Link to source: https://mobilitaetspanel.ifv.kit.edu/english/

Federal Highway Administration. (2022). Summary of Travel Trends: 2022 National Household Travel Survey. US Department of Transportation. Link to source: https://nhts.ornl.gov/assets/2022/pub/2022_NHTS_Summary_Travel_Trends.pdf

Goel, D., & Gupta, S. (2017). The Effect of Metro Expansions on Air Pollution in Delhi. The World Bank Economic Review, 31(1), 271–294. Link to source: https://doi.org/10.1093/wber/lhv056

Gouldson, A., Sudmant, A., Khreis, H., & Papargyropoulou, E. (2018). The Economic and Social Benefits of Low-Carbon Cities: A Systematic Review of the Evidence. Link to source: https://urbantransitions.global/en/publication/the-economic-and-social-benefits-of-low-carbon-cities-a-systematic-review-of-the-evidence/ 

Guo, S., & Chen, L. (2019). Can urban rail transit systems alleviate air pollution? Empirical evidence from Beijing. Growth and Change, 50(1), 130–144. Link to source: https://doi.org/10.1111/grow.12266 

Health Affairs. (2021). Public Transportation in the U.S. RWJF. Link to source: https://www.rwjf.org/content/rwjf-web/us/en/insights/our-research/2021/07/public-transportation-in-the-us-a-driver-of-health-and-equity.html 

Hemmat, W., Hesam, A. M., & Atifnigar, H. (2023). Exploring noise pollution, causes, effects, and mitigation strategies: A review paper. European Journal of Theoretical and Applied Sciences, 1(5), Article 5. Link to source: https://doi.org/10.59324/ejtas.2023.1(5).86

Ilie, N., Iurie, N., Alexandr, M., & Vitalie, E. (2014). Rehabilitation of the tram DC traction with modern power converters. 2014 International Conference and Exposition on Electrical and Power Engineering (EPE), 704–709. Link to source: https://doi.org/10.1109/ICEPE.2014.6970000

International Transport Forum. (2020). Good to Go? Assessing the Environmental Performance of New Mobility (Corporate Partnership Board). OECD. Link to source: https://www.itf-oecd.org/sites/default/files/docs/environmental-performance-new-mobility.pdf

IPCC. (2023). Renewable Energy Sources and Climate Change Mitigation—IPCC. Link to source: https://www.ipcc.ch/report/renewable-energy-sources-and-climate-change-mitigation/

Kennedy, C. A. (2002). A comparison of the sustainability of public and private transportation systems: Study of the Greater Toronto Area. Transportation, 29(4), 459–493. Link to source: https://doi.org/10.1023/A:1016302913909

Kuminek, T. (2013). Energy Consumption in Tram Transport. Logistics and Transport. Link to source: https://www.semanticscholar.org/paper/Energy-Consumption-in-Tram-Transport-Kuminek/2aa2d97130a8e51ea7f64913c2065e8437126774

Lim, L. K., Muis, Z. A., Hashim, H., Ho, W. S., & Idris, M. N. M. (2021). Potential of Electric Bus as a Carbon Mitigation Strategies and Energy Modelling: A Review. Chemical Engineering Transactions, 89, 529–534. Link to source: https://doi.org/10.3303/CET2189089

Lovasi, G. S., Treat, C. A., Fry, D., Shah, I., Clougherty, J. E., Berberian, A., Perera, F. P., & Kioumourtzoglou, M.-A. (2023). Clean fleets, different streets: Evaluating the effect of New York City’s clean bus program on changes to estimated ambient air pollution. Journal of Exposure Science & Environmental Epidemiology, 33(3), 332–338. Link to source: https://doi.org/10.1038/s41370-022-00454-5

Litman, T. (2024). Evaluating Public Transit Benefits and Costs. Link to source: https://www.vtpi.org/tranben.pdf 

Loukaitou-Sideris, A. (2014). Fear and safety in transit environments from the women’s perspective. Security Journal, 27(2), 242–256. Link to source: https://doi.org/10.1057/sj.2014.9

Mahmoud, M., Garnett, R., Ferguson, M., & Kanaroglou, P. (2016). Electric buses: A review of alternative powertrains. Renewable and Sustainable Energy Reviews, 62, 673–684. Link to source: https://doi.org/10.1016/j.rser.2016.05.019

Martinez, D., Mitnik, O., Salgado, E., Yãnez-Pagans, P., & Scholl, L. (2020). Connecting to Economic Opportunity: The Role of Public Transport in Promoting Women’s Employment in Lima | Journal of Economics, Race, and Policy. Link to source: https://link.springer.com/article/10.1007/s41996-019-00039-9 

Mees, P. (2010). Transport for Suburbia: Beyond the Automobile Age. Earthscan. Link to source: https://www.routledge.com/Transport-for-Suburbia-Beyond-the-Automobile-Age/Mees/p/book/9781844077403?srsltid=AfmBOoqLpikgSll7C5BzwVRtvO9Ji0JgM1XAHe60uh_s1qGh3YxCr018 

Norton, P. D. (2011). Fighting Traffic: The Dawn of the Motor Age in the American City. MIT Press. Link to source: https://mitpress.mit.edu/9780262516129/fighting-traffic/ 

Ortiz, F. (2002). Biodiversity, the City, and Sprawl. Boston University Law Review, 82(1), 145–194. Link to source: https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3499945 

Padeiro, M., Louro, A., & da Costa, N. M. (2019). Transit-oriented development and gentrification: A systematic review. Transport Reviews, 39(6), 733–754. Link to source: https://doi.org/10.1080/01441647.2019.1649316

Prieto-Curiel, R., & Ospina, J. P. (2024). The ABC of mobility. Environment International, 185, 108541. Link to source: https://doi.org/10.1016/j.envint.2024.108541

Qi, Y., Liu, J., Tao, T., & Zhao, Q. (2023). Impacts of COVID-19 on public transit ridership. International Journal of Transportation Science and Technology, 12(1), 34–45. Link to source: https://doi.org/10.1016/j.ijtst.2021.11.003

Rodrigues, A. L. P., & Seixas, Sonia. R. C. (2022). Battery-electric buses and their implementation barriers: Analysis and prospects for sustainability. Sustainable Energy Technologies and Assessments, 51, 101896. Link to source: https://doi.org/10.1016/j.seta.2021.101896

Rodriguez Mendez, Q., Fuss, S., Lück, S., & Creutzig, F. (2024). Assessing global urban CO2 removal. Nature Cities, 1(6), 413–423. Link to source: https://doi.org/10.1038/s44284-024-00069-x

Serulle, N. U., & Cirillo, C. (2016). Transportation needs of low income population: A policy analysis for the Washington D.C. metropolitan region. Public Transport, 8(1), 103–123. Link to source: https://doi.org/10.1007/s12469-015-0119-2 

Schaller, B. (2017). Unsustainable? The Growth of App-Based Ride Services and Traffic, Travel and the Future of New York City. Schaller Consulting. Link to source: http://schallerconsult.com/rideservices/unsustainable.htm 

Schrag, Z. M. (2000). “The Bus Is Young and Honest”: Transportation Politics, Technical Choice, and the Motorization of Manhattan Surface Transit, 1919-1936. Technology and Culture, 41(1), 51–79. Link to source: https://muse.jhu.edu/article/33496 

Sertsoz, M., Kusdogan, S., & Altuntas, O. (2013). Assessment of Energy Efficiencies and Environmental Impacts of Railway and Bus Transportation Options. In I. Dincer, C. O. Colpan, & F. Kadioglu (Eds.), Causes, Impacts and Solutions to Global Warming (pp. 921–931). Springer. Link to source: https://doi.org/10.1007/978-1-4614-7588-0_48

Statistics Netherlands. (2024). Mobility; per person, personal characteristics, modes of travel and regions [Webpage]. Statistics Netherlands. Link to source: https://www.cbs.nl/en-gb/figures/detail/84709ENG

Swanstrom, T., Winter, W., & Wiedlocher, L. (2010). The Impact of Increasing Funding for Public Transit. Link to source: https://librarysearch.adelaide.edu.au/discovery/fulldisplay/alma9928308820601811/61ADELAIDE_INST:UOFA 

Tayal, D., & Mehta, A. (2021). Working Women, Delhi Metro and Covid-19: A Case Study in Delhi-NCR | The Indian Journal of Labour Economics. Link to source: https://link.springer.com/article/10.1007/s41027-021-00313-1?fromPaywallRec=true 

UITP. (2024). A global analysis of transit data. CityTransit Data. Link to source: https://citytransit.uitp.org

US Department of Transportation. (2010). Public transportation’s role in responding to climate change. US Department of Transportation. Link to source: https://www.transit.dot.gov/sites/fta.dot.gov/files/docs/PublicTransportationsRoleInRespondingToClimateChange2010.pdf

Van Acker, V., & Witlox, F. (2010). Car ownership as a mediating variable in car travel behaviour research using a structural equation modelling approach to identify its dual relationship. Journal of Transport Geography, 18(1), 65–74. Link to source: https://doi.org/10.1016/j.jtrangeo.2009.05.006

Venter, C., Jennings, G., Hidalgo, D., & Pineda, A. (2017). The equity impacts of bus rapid transit: A review of the evidence and implications for sustainable transport: International Journal of Sustainable Transportation: Vol 12 , No 2—Get Access. Link to source: https://www.tandfonline.com/doi/full/10.1080/15568318.2017.1340528 

Xiao, C., Goryakin, Y., & Cecchini, M. (2019). Physical Activity Levels and New Public Transit: A Systematic Review and Meta-analysis. American Journal of Preventive Medicine, 56(3), 464–473. Link to source: https://doi.org/10.1016/j.amepre.2018.10.022 

Credits

Lead Fellow

  • Cameron Roberts, Ph.D.

Contributors

  • Ruthie Burrows, Ph.D.

  • James Gerber, Ph.D.

  • Yusuf Jameel, Ph.D. 

  • Daniel Jasper

  • Heather Jones, Ph.D.

  • Heather McDiarmid, Ph.D.

  • Alex Sweeney

Internal Reviewers

  • Aiyana Bodi

  • Hannah Henkin

  • Ted Otte

  • Amanda D. Smith, Ph.D.

  • Chrstina Swanson, Ph.D.

Effectiveness

Our calculations suggest that an efficiently designed public transit system using the best available vehicle technologies (especially battery-electric buses) would save 58 t CO₂‑eq /million pkm (0.000058 t CO₂‑eq /pkm) on a 100-yr basis compared with fossil fuel–powered cars, in line with the estimates by other large transportation focused organizations (International Transport Forum, 2020; US Department of Transportation, 2010). This number is highly sensitive to public transit vehicle occupancy, which we estimated using the most recent available data (American Public Transit Association, 2021). Increasing the number of trips taken via public transit would likely increase occupancy, although ideally not to the point of passenger discomfort. This elevated ridership would significantly reduce public transit’s pkm emissions.

To arrive at this figure, we first estimated the emissions of fossil fuel–powered cars as 115 t CO₂‑eq /million pkm (0.000115 t/pkm, 100-yr basis). We then separately calculated the emissions of commuter rail, metros and subways, trams and light rail systems, and electric buses. We used data on the modal share of different vehicles within public transit systems around the world (although much of the available data are biased towards systems in the United States and Europe) to determine what each transit system’s emissions would be per million pkm given our per-million-pkm values for different transit vehicles (UITP, 2024). The median of these city-level values is 58 t CO₂‑eq /pkm (0.000058 t/pkm, 100-yr basis). Subtracting this value from the per-pkm emissions for cars gives us the public transit GHG savings figure cited above. Note that none of these values includes embodied emissions (such as emissions from producing cars, buses, trains, roads, etc.), or upstream emissions (such as those from oil refineries).

Pessimistic assumptions regarding the emissions and occupancy of public transit vehicles, and optimistic assumptions about emissions from cars, can suggest a much more marginal climate benefit from public transit (see the 25th percentile row in Table 1). In most cases, however, well-managed public transit is likely to produce a meaningful climate benefit. Such an outcome will depend on increasing the average occupancy of vehicles, which faces a challenge because transit has seen declining occupancies since the COVID-19 pandemic (Qi et al., 2023). For this reason, encouraging additional use of public transit networks without expanding these networks can have an outsized impact because it will allow the substitution of fossil fuel–powered car trips by trips on public transit vehicles for which emissions would not change meaningfully as a result of adding passengers.

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Table 1. Effectiveness at reducing emissions.

Unit: t CO₂‑eq/million pkm, 100-yr basis

25th percentile 0.127
Mean 61.76
Median (50th percentile) 58.27
75th percentile 106.7

The extremely large range of values between the 25th and 75th percentile is the result of 1) the large diversity of public transit systems in the world and 2) multiplying multiple layers of uncertainty (e.g., varying estimates for occupancy, energy consumption per vehicle kilometer (vkm), percent of pkm reliant on buses vs. trains).

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Cost

Under present-day public transit costs and revenues, it costs the transit provider US$0.23 to transport a single passenger one kilometer. In comparison, travel by car costs the consumer US$0.42/pkm. On a per passenger basis, for the transit provider, public transit is almost 50% cheaper than car transportation, costing US$0.20/pkm less. Combined with the emissions reductions from using public transit, this means that the emissions reductions from shifting people out of cars onto public transit has a net negative cost, saving US$3,300/t CO₂‑eq mitigated (Table 2). 

This figure includes all relevant direct costs for travel by public transit and by car, including the costs of infrastructure, operations, vehicle purchase, and fuel. It does not include external costs, such as medical costs resulting from car crashes. Capital costs (i.e., the large fixed costs of building public transit infrastructure) are accounted for via the annualized capital costs listed in public transit agencies’ financial reports. 

A very large proportion of the total costs of providing public transit is labor (e.g., wages for bus drivers and station attendants). This cost is unlikely to come down as a result of technological innovations (Bloomberg New Energy Finance, 2018).

For an individual passenger, however, the marginal costs of public transit (i.e., the fares they pay) can sometimes be higher than the marginal costs of driving. This is in large part due to many external costs of driving which are borne by society at large (Litman, 2024). However, increasing the public transit availability would likely increase occupancy, which would in turn drive costs down.

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Table 2. Cost per unit of climate impact.

Unit: 2023 US$/t CO₂‑eq , 100-yr basis

Median –3300

Transit provider cost, not passenger cost.

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Learning Curve

Public transit is a largely mature technology with limited opportunities for radical cost-saving innovation. While our research did not find any papers reporting a learning curve in public transit as a whole, battery-electric buses are in fact subject to many of the same experience effects of other battery-electric vehicles. Although there are no studies assessing declines in the cost of electric buses as a whole, there are studies assessing learning curves for their batteries, which is the most costly component. The cost of batteries used in battery-electric buses has declined 19.25% with each doubling of installed capacity (Table 3).

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Table 3. Learning rate: drop in cost per doubling of the installed solution base.

Unit: %

25th percentile 18.63
Mean 19.25
Median (50th percentile) 19.25
75th percentile 19.88

This applies only to the cost of batteries in electric buses, not to public transportation as a whole.

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Speed of Action

Speed of action refers to how quickly a climate solution physically affects the atmosphere after it is deployed. This is different from speed of deployment, which is the pace at which solutions are adopted.

At Project Drawdown, we define the speed of action for each climate solution as emergency brake, gradual, or delayed.

Enhance Public Transit is a GRADUAL climate solution. It has a steady, linear impact on the atmosphere. The cumulative effect over time builds as a straight line.

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Caveats

Public transit competes for passengers not just with cars, but also with other transportation modes – some of which have lower emissions on average. If an increase in public transit’s modal share comes at the expense of nonmotorized transportation (i.e., pedestrian travel or cycling), or electric bicycles, this will result in a net increase in emissions. Similarly, public transit could generate additional trips that would not have occurred if the public transit network those trips were taken on did not exist. Under this scenario, a net increase in emissions would occur; however, these new trips might bring additional social benefits that would outweigh these new emissions.

Low occupancy could also diminish the climate benefit of enhancing public transit. While it is certainly possible to build effective and efficient public transit networks in suburban and rural areas, there is a risk that such networks could have high per-pkm GHG emissions if they have low average occupancy (Mees, 2010). It is therefore important to efficiently plan public transit networks, ensure vehicles are right-sized and have efficient powertrains, and promote high levels of ridership even in rural areas to maximize the climate benefit of these kinds of networks.

Upscaling public transit networks – and, crucially, convincing more motorists to use them – is an enduring challenge that faces cultural resistance in some countries, issues with cost, and sometimes a lack of political will. Successfully enhancing public transit will require that these hurdles are overcome.

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Current Adoption

In cities around the world surveyed over the last 15 years, public transit has an average modal share of approximately 26.2% of trips. In comparison, fossil fuel–powered cars account for 51.4% of all trips, while nonmotorized transportation accounts for 22.4% (Prieto-Curiel & Ospina, 2024). The 26.2% of trips taken via public transit corresponds to approximately 7.2 trillion pkm traveled on public transit in cities every year (Table 4).

We calculated adoption from modal share data (i.e., the percentage of trips in a given city taken via various modes of transportation). We estimated total pkm traveled by assuming a global average daily distance traveled based on travel surveys from the United States as well as several European countries (Christensen & Vázquez, 2013; Department for Transport, 2024; Ecke, 2023; Federal Highway Administration, 2022; Statistics Netherlands, 2024). Most of these data did not account for population, and therefore gave too much weight to small cities and skewed the results. Therefore, we used Prieto-Curiel and Ospina’s (2024) global population-weighted mean modal share of the ITF’s (2021) urban passenger market as our global adoption value.

We assumed that Prieto-Curiel and Ospina’s data refer only to urban modal share. Public transit can be useful in rural areas (Börjesson et al., 2020), but we did not attempt to estimate rural public transit adoption in this assessment.

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Table 4. Current (2024) adoption level.

Unit: million pkm/yr 

Population-weighted mean 6,784,000
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Adoption Trend

Based on data from Prieto-Curiel and Ospina (2024) and the UITP (2024) for 1,097 cities worldwide, the rate of adoption of public transit has not changed since 2010, with the median annual growth rate equal to 0 (Table 5). This was calculated using all of the cities in Prieto-Curiel and Ospina’s (2024) database for which modal share data exist.

Despite the lack of a global trend in public transit use, some cities, including Amsterdam, Edinburgh, and Leeds, report double-digit growth rates in the use of public transit.

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Table 5. 2023–2024 adoption trend.

Unit: million pkm/yr

25th percentile -301,100
Mean 30,802
Median (50th percentile) 0.00
75th percentile 774,100
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Adoption Ceiling

Public transit could theoretically replace all trips currently undertaken by fossil fuel–powered cars. This would amount to 23 trillion pkm on public transit annually, worldwide (Table 6). This would not be feasible to achieve in practice, as it would require construction of new public transit vehicles and infrastructure on an unfeasibly large scale, and massive changes to living patterns for many people. It would also be much more expensive than we calculated above, because such a change would require extending public transit coverage into areas where it would be highly uneconomic. Public transit is capable of providing a good transportation option in rural areas, but there is a limit to its benefits when population densities are low even by rural standards. Even in cities, this scenario would require a radical redesign of some neighborhoods to prioritize public transit. Such large public transit coverage would also inevitably shift other modes of transportation, such as pedestrian travel and cycling, leading to an even higher pkm total than that suggested by current adoption of fossil fuel–powered cars.

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Table 6. Adoption ceiling.

Unit: million pkm/yr

Median (50th percentile) 22,502,000
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Achievable Adoption

The achievable range of public transit adoption is 12.0 to 17.7 trillion pkm traveled by public transit in cities globally.

To estimate the upper bound of achievable adoption, we assumed that urban trips taken by fossil fuel–powered car (currently 51.4% of trips globally) can be shifted to public transit until public transit increases to 76.6% of trips (the current highest modal share of public transit in any city with a population of more than 1 million) or until car travel decreases to 12.0% of trips (the current lowest modal share of fossil fuel–powered cars in any city with a population of more than 1 million). This equals a shift of 10.9  trillion pkm from fossil fuel–powered car travel to public transit, which, added to present-day public transit trips (6.8 trillion trips/yr), equals 17.7 trillion pkm/yr (Table 7).

To set the lower bound, we performed the same calculation as above, but on a regional basis, adding up all the resultant modal shifts to get a global figure. For example, every northern European city might reach the public transit modal share of London (44.5% of trips), while every South Asian city might reach that of Mumbai (52.0% of trips). Having done that, we then added together the public transit adoption rates from all world regions, apart from three (Polynesia, Micronesia, and Melanesia) for which we did not find any modal share data. This corresponds to a shift of 5.3 trillion pkm/yr from cars to public transit, and a total achievable public transit adoption rate of 12.0 trillion pkm/yr.

Achieving both of these levels of adoption would require not only major investments in expanding public transit networks, but also major changes in how cities are planned so as to allow more areas to be effectively served by transit. These levels of adoption would also require overcoming cultural and political resistance to abandoning cars in favor of public modes. However, unlike the scenario discussed under Adoption Ceiling, these scenarios are feasible, since they are based on real achievements by cities around the world.

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Table 7. Range of achievable adoption levels.

Unit: million pkm/yr

Current adoption 6,784,000
Achievable – low 12,030,000
Achievable – high 17,670,000
Adoption ceiling 22,500,000
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If all public transit trips were taken by fossil fuel–powered cars instead of by public transit, they would result in an additional 0.40 Gt CO₂‑eq/yr of emissions (Table 8).

The global potential climate impact of enhancing public transit, if all car trips were shifted onto public transit systems, is 1.31 Gt. As discussed under Adoption Ceiling, this is an unrealistic scenario.

In a more realistic scenario, if every city in the world shifted car traffic onto public transit until it reached the public transit modal share of Hong Kong (i.e., the high estimate of achievable adoption), it would save 1.03 Gt CO₂‑eq/yr globally. Meanwhile, if every city shifts car trips to public transit until it reaches the car modal share of the region’s least car-dependent city (i.e., the low estimate of achievable adoption), it would save 0.701 Gt CO₂‑eq/yr.

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Table 8. Climate impact at different levels of adoption.

Unit: Gt CO₂‑eq/yr, 100-yr basis

Current adoption 0.395
Achievable – low 0.701
Achievable – high 1.029
Adoption ceiling 1.311
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Additional Benefits

Income and Work

Investment in enhancing public transit can also generate substantial economic returns. The APTA estimated that each US$1 billion invested in transit can create 49,700 jobs and yield a five-to-one economic return (APTA, 2020). According to another study, shifting 50% of highway funds to mass transit systems in 20 U.S. metropolises could generate more than 1 million new transit jobs within five years (Swanstrom et al., 2010). 

Health

Improved air quality due to enhanced public transit has direct health benefits, such as lowering cardiovascular disease risk, and secondary health benefits, such as increased physical activity (Xiao et al., 2019), fewer traffic-related injuries, lower rates of cancer, and enhanced access to health-care facilities and nutritious food (Gouldson et al., 2018; Health Affairs, 2021).

Equality

Limited access to transportation restricts labor participation, particularly for women. Expanding public transit can foster gender equity by improving women’s access to employment opportunities. For example, in Peru expansion of public transit has led to improvements in women’s employment and earnings (Martinez et al., 2020). Similarly, in India, the extension of the light rail system in Delhi has increased women’s willingness to commute for work (Tayal & Mehta, 2021).

Public transit enhances community connectivity by providing accessible transportation options. Expanded mobility allows individuals to reach employment, health-care, education, and recreational sites with greater ease, heightening social inclusion. The social equity benefits of public transit are especially significant for low-income people in terms of time and cost savings and safety and health benefits (Serulle & Cirillo, 2016; Venter et al., 2017). 

Nature Protection

An indirect benefit of enhanced public transit is its contribution to reducing resource consumption, such as the minerals used in manufacturing personal vehicles. Enhanced public transit can also improve land-use efficiency by curbing urban sprawl, which helps reduce pollution and limit biodiversity loss (Ortiz, 2002). 

Air Quality

GHG emissions from transportation are often emitted with other harmful air pollutants. Consequently, reducing fuel consumption by replacing transport by fossil fuel–powered cars with public transit can lead to cleaner air. The scale of this benefit varies by location and is influenced by differences in emission levels between private and public transit travels and the relative demand substitutability between modes (Beaudoin et al., 2015). For U.S. cities, significant investment in public transit could cut pollution around 1.7% on average (Borck, 2019). The benefits are more significant in low- and middle-income countries, where fossil fuel–powered cars are more polluting due to lenient air quality regulations (Goel & Gupta, 2017; Guo & Chen, 2019).

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Risks

If expanded service on high-quality public transit systems replaced journeys from nonmotorized transportation or electric bicycles rather than from cars – or if expanded service on high-quality public transit systems generated journeys that would not have otherwise happened – this will have a net-negative climate impact, since public transit has higher per-pkm GHG emissions than electric bicycles or not traveling (International Transport Forum, 2020). 

There may be cases where public transit networks cannot be implemented efficiently enough to provide a meaningful benefit compared to fossil fuel–powered cars in terms of GHG emissions. This would occur in places where there are so few potential riders that most trips would have a very low occupancy. The result would be a much higher rate of emissions per pkm. However, effective public transit networks can be built in suburban and even rural areas (Börjesson et al., 2020; Mees, 2010).

Finally, expanding public transit networks has proven very difficult in recent years. Entrenched preferences for car travel, reluctance on the part of governments to invest heavily in new transit infrastructure, and local political challenges over land use, noise, gentrification, and similar issues are all obstacles to increased public transit use. Public transit expansion has faced stronger headwinds in recent years in particular, due to both the impact of the COVID-19 pandemic and competition from new (and mostly less sustainable) mobility services, such as app-based ride-hailing (Shaller, 2017).

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Interactions with Other Solutions

Reinforcing

For people living without cars, public transit provides a crucial service that is hard to replace for certain kinds of trips, such as trips over long distances, with small children, or carrying large objects. As a result, public transit plays a large role in making it more viable for people to live without owning a car (Brown, 2017). Research suggests that the key to a low-carbon mobility system is to reduce the need for people to own cars altogether (Van Acker & Witlox, 2010).

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Competing 

Electric cars, hybrid cars and electric scoters and motorcycles, and public transit compete for pkm. Consequently, increased use of public transit could reduce kilometers traveled using electric and hybrid cars and electric scooters and motorcycles.

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Dashboard

Solution Basics

million passenger kilometers (million pkm)

t CO₂-eq (100-yr)/unit
00.12758.27
units/yr
Current 6.784×10⁶ 01.203×10⁷1.767×10⁷
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 0.395 0.7011.029
US$ per t CO₂-eq
-3,300
Gradual

CO₂, CH₄, N₂O, BC

Trade-offs

Public transit vehicles are sometimes unsafe, particularly for vulnerable groups such as women (Loukaitou-Sideris, 2014). In some circumstances – although this remains controversial – new public transit routes can also lead to gentrification of neighborhoods, forcing people to move far away from city centers and use cars for travel (Padeiro et al., 2019). 

Expansion of public transit networks could also have negative consequences in areas directly adjacent to transit infrastructure. Diesel buses create air pollution (Lovasi et al., 2022), and public transit networks of all types can create noise pollution (Hemmat et al., 2023).

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Population (millions)
1
10
30
Active Mobility
Public Transport
Private Cars

Primary mode of transport

Mapping the primary mode of transportation reveals mobility patterns and opportunities to shift travel toward lower-emitting modes.

Prieto-Curiel, R. and Ospina, Juan P. (2024). The ABC of mobility [Data set]. Environmental International, Link to source: https://doi.org/10.1016/j.envint.2024.108541. Retrieved May 9, 2025 from Link to source: https://github.com/rafaelprietocuriel/ModalShare

Population (millions)
1
10
30
Active Mobility
Public Transport
Private Cars

Primary mode of transport

Mapping the primary mode of transportation reveals mobility patterns and opportunities to shift travel toward lower-emitting modes.

Prieto-Curiel, R. and Ospina, Juan P. (2024). The ABC of mobility [Data set]. Environmental International, Link to source: https://doi.org/10.1016/j.envint.2024.108541. Retrieved May 9, 2025 from Link to source: https://github.com/rafaelprietocuriel/ModalShare

Maps Introduction

Public transit is most effective in urban areas with high population density, where buses, subways, trams, and commuter rail can efficiently carry large numbers of passengers. Electrified or low-emission transit modes achieve the greatest climate impact, especially in regions with clean electricity grids (Bloomberg New Energy Finance, 2018). However, even diesel-based public transit systems can outperform fossil fuel-powered cars on a per-pkm basis if they have high ridership and operate efficiently.

Socioeconomic and political factors, including investment capacity, institutional coordination, and public perceptions of reliability, safety, and comfort, highly influence the adoption and effectiveness of public transit. Regions with well-funded public infrastructure, integrated fare systems, and strong governance tend to have the highest adoption and climate benefits. Conversely, underinvestment, informal transit dominance, or poorly maintained systems can undermine public transit’s potential (Börjesson et al., 2020; Mees, 2010).

High public transit adoption is seen in Western and Northern Europe, Post-Soviet countries, East Asia (including Japan, South Korea, and China), and some Latin American cities, like Bogotá and Santiago. In contrast, many developing regions face barriers to public transit expansion, such as inadequate funding, urban sprawl, or a reliance on informal minibus systems. However, these same areas offer some of the highest potential for impact. Rapid urbanization, growing demand for mobility, and severe air quality challenges create strong incentives to expand and modernize transit networks.

Action Word
Enhance
Solution Title
Public Transit
Classification
Highly Recommended
Lawmakers and Policymakers
  • Use public transit and create incentive programs for government employees to use public transit.
  • Improve and invest in local public transit infrastructure, increasing routes and frequency while improving onboard safety, especially for women.
  • Electrify public buses, vans, and other vehicles used in the public transit system.
  • Implement the recommendations of transit-oriented development, such as increasing residential and commercial density, placing development near stations, and ensuring stations are easily accessible.
  • Provide online information, ticketing, and payment services.
  • Implement regional or nationwide public transit ticketing systems.
  • Consider a wide range of policy options that include demand-side options, such as free fare or fare reductions, and that are informed by citizen-centered approaches.
  • Create dedicated coordinating bodies across government agencies, businesses, and the public to develop public transit.
  • Disincentivize car trips in areas serviced by public transit through reduced access, increases in parking fares, congestion charges, taxes, or other means.
  • Incorporate social signaling in public transit information and signage, such as smiley faces and “sustainable transport” labels.
  • Develop public transit awareness campaigns – starting from early childhood – focusing on internally motivating factors such as money saved, health benefits, reduced pollution, free time while traveling, and lifestyle sustainability.

Further information:

Practitioners
  • Use public transit and create incentive programs for government employees to utilize public transit.
  • Increase routes and frequency while also improving onboard safety, especially for women.
  • Electrify public buses, vans, and other vehicles used in the public transit system.
  • Incorporate social signaling in public transit information and signage, such as smiley faces and “sustainable transport” labels.
  • Provide online information, ticketing, and payment services
  • Implement regional or nationwide public transit ticketing systems.
  • Consider a wide range of policy options that include demand-side options, such as free fare or fare reductions, and that are informed through citizen-centered approaches.
  • Create dedicated coordinating bodies across government agencies, businesses, and the public to develop public transit.
  • Develop public transit awareness campaigns – starting from early childhood – focusing on internally motivating factors such as money saved, health benefits, reduced pollution, free time while traveling, and a sustainable lifestyle.

Further information:

Business Leaders
  • Use public transit and encourage employees to do so when feasible.
  • Encourage public transit use for company purposes.
  • Offer employees who agree to forego a free parking space the annualized cash value or cost of that parking space as a salary increase.
  • Incorporate company policies on public transit use into company sustainability and emission reduction initiatives and communicate how they support broader company goals.
  • Ensure your business is accessible via public transit and offer information on nearest access points both online and in person.
  • Offer employees pre-tax commuter benefits to include reimbursement for public transit expenses.
  • Create and distribute educational materials for employees on commuting best practices.
  • Partner with, support, and/or donate to infrastructure investments and public transit awareness campaigns.
  • Advocate for better public transit systems with city officials.

Further information:

Nonprofit Leaders
  • Use public transit and encourage staff to do so when feasible.
  • Offer staff pre-tax commuter benefits to include reimbursement for public transit expenses.
  • Offer employees who agree to forego a free parking space the annualized cash value or cost of that parking space as a salary increase.
  • Expand access to underserved communities by providing fare assistance through microgrants and/or public-private partnerships.
  • Create, support, or partner with existing public transit awareness campaigns that – starting from early childhood – focus on internally motivating factors such as money saved, health benefits, reduced pollution, free time while traveling, and a sustainable lifestyle.
  • Ensure your office is accessible via public transit and offer information – online and in person – on the nearest access points.
  • Advocate to policymakers for improved infrastructure and incentives for riders.
  • Advocate for infrastructure improvements and note specific locations where improvements can be made.
  • Encourage local businesses to create employee incentives.
  • Host or support community participation in local public transit infrastructure design.
  • Join public-private partnerships to encourage, improve, or operate public transit.

Further information:

Investors
  • Use public transit and encourage staff to do so when feasible.
  • Encourage public transit use for company purposes.
  • Invest in electric battery and component suppliers for public buses and vehicle fleets.
  • Deploy capital to efforts that improve public transit comfort, convenience, access, and safety.
  • Seek investment opportunities that reduce material and maintenance costs for public transit.

Further information:

Philanthropists and International Aid Agencies
  • Use public transit and encourage staff to do so when feasible.
  • Award grants to local organizations advocating for improved public transit and services.
  • Expand access to underserved communities by providing fare assistance through microgrants and/or public-private partnerships.
  • Improve and finance local infrastructure and public transit capacity.
  • Build local capacity for infrastructure design, maintenance, and construction.
  • Assist with local policy design or provide means for assessments, data collection, citizen participation, and other steps in the policymaking process.
  • Create, support, or partner with existing public transit awareness campaigns that – starting from early childhood – focus on internally motivating factors such as money saved, health benefits, reduced pollution, free time while traveling, and a sustainable lifestyle.

Further information:

Thought Leaders
  • Lead by example and use public transit regularly.
  • Create, support, or partner with existing public transit awareness campaigns that – starting from early childhood – focus on internally motivating factors such as money saved, health benefits, reduced pollution, free time while traveling, and a sustainable lifestyle.
  • Share detailed information on local public transit routes.
  • Assist with local policy design or provide means for assessments, data collection, citizen participation, and other steps in the policymaking process.
  • Advocate to policymakers for improved infrastructure, noting specific locations that need improvements and incentives for riders.

Further information:

Technologists and Researchers
  • Use public transit and encourage your colleagues to use public transit when feasible.
  • Improve electric batteries and electrification infrastructure for public buses and vehicles.
  • Develop models for policymakers to demonstrate the impact of public transit policies on pollutant emissions, health, and other socioeconomic variables.
  • Conduct randomized control trials and collect longitudinal data on the impacts of interventions to increase public transit usage.
  • Innovate better, faster, and cheaper public transit networks – focusing on infrastructure, operations, and public transit vehicles.

Further information:

Communities, Households, and Individuals
  • Use public transit and encourage your household and neighbors to use public transit when feasible.
  • Share your experiences with public transit, as well as tips and reasons for choosing this mode of transportation.
  • Advocate to local officials for infrastructure improvements and note specific locations where improvements can be made.
  • Advocate to employers and local businesses to provide incentives and start local initiatives.

Further information:

Sources
Evidence Base

Consensus of effectiveness in reducing transportation emissions: High

Experts agree that public transit usually produces fewer GHG/pkm than fossil fuel–powered cars (Bloomberg New Energy Finance, 2018; Brunner et al., 2018; Ilie et al., 2014; International Transport Forum, 2020; Kennedy, 2002; Kuminek, 2013; Lim et al., 2021; Mahmoud et al., 2016; Rodrigues & Seixas, 2022; Sertsoz et al., 2013). There is also consensus on two points: First, shifting people from cars to public transit even under status-quo emissions levels will reduce transport emissions overall; second, opportunities exist to decarbonize the highest-emitting parts of public transit systems through electrification, especially buses (Bloomberg New Energy Finance, 2018).

According to the Intergovernmental Panel on Climate Change (IPCC, 2023), public transit can help decrease vehicle travel and lower GHG emissions by reducing both the number and length of trips made in fossil fuel–powered cars (medium confidence). Adjustments to public transportation operations – such as increasing bus stop density, reducing the distance between stops and households, improving trip duration and frequency, and lowering fares – can encourage a shift from fossil fuel–powered car use to public transit.

Bloomberg New Energy Finance (2018) provides a good overview of the state of electric buses – a technology crucial to reduce the public transit fleet’s fossil fuel consumption, and help transition these fleets entirely to electric power. It determined that electric buses have significantly lower operating costs and can be more cost-effective than conventional buses when considering total ownership costs.

Litman (2024) found that “High quality (relatively fast, convenient, comfortable, and integrated) transit can attract discretionary passengers who would otherwise drive, which reduces traffic problems including congestion, parking costs, accidents, and pollution emissions. This provides direct user benefits, since they would not change mode if they did not consider themselves better off overall.”

The results presented in this document summarize findings from 28 reviews and meta-analyses and 23 original studies reflecting current evidence from 32 countries, primarily the American Public Transit Association (APTA, 2020), Bloomberg New Energy Finance (2018), International Transport Forum (2020), and UITP (2024). We recognize this limited geographic scope creates bias, and hope this work inspires research and data sharing on this topic in underrepresented regions.

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Updated Date

Increase Carpooling

Submitted by Drawdown Admin on
Sector
Transportation
Mode
Cut Emissions
Cluster
Shift to Alternatives
Image
Carpool lane sign
Coming Soon
Off
Summary

Carpooling entails increasing the occupancy of passenger cars, including taxis, pickup trucks, motorhomes, passenger vans and other such vehicles but not including two- or three-wheeled, freight, public transit, or commercial vehicles, such as buses, heavy trucks, and commercial vans. It replaces the practice of driving alone.

We define Increase Carpooling as having at least one passenger per car in addition to the driver (two passengers for ride-hailing). We consider a fully adopted carpool trip as having 2 passengers for a car occupancy of three. New adoption is considered as any passenger kilometer (pkm)/yr avoided from an increase in the 2023 current adoption baseline (average occupancy of 1.5).

Income & work,Health,Equality
Air quality
Description for Social and Search
Carpooling is a Highly Recommended climate solution. By increasing car occupancy, it cuts per-capita GHG emissions, reduces congestion, maximizes the use of existing infrastructure, and saves money.
Overview

Carpooling involves transporting multiple people in a single car. Because carpooling increases the number of passengers per vehicle, it reduces emissions per pkm (International Transport Forum [ITF], 2021). However, the actual impact depends on how the carpool trip is organized – for example, whether it replaces solo car trips or shifts people away from public or active transport.

Carpooling is generally more efficient when ride-matching is optimized. If trips involve detours to pick up passengers, the benefits can be reduced. Similarly, carpooling may offer less advantage in areas with strong public transportation systems if it replaces public transport use (Schaller, 2021).

In addition to reducing emissions of CO₂, methane, nitrous oxide, and black carbon (ITF, 2023), carpooling can help alleviate traffic congestion and reduce demand for parking (Dong et al., 2025). It may also lower transportation costs for participants (Fulton et al., 2020). However, the full benefits depend on usage patterns, geographic context, and integration with other transport modes.

AAA. (2022). AAA’s your driving costs. Link to source: https://exchange.aaa.com/automotive/aaas-your-driving-costs 

Adelé, S., & Dionisio, C. (2020). Learning from the real practices of users of a smart carpooling app. European Transport Research Review, 12(1), Article 39. Link to source: https://doi.org/10.1186/s12544-020-00429-3  

Anenberg, S., Miller, J., Henze, D., & Minjares, R. (2019). A global snapshot of the air pollution-related health impacts of transportation sector emissions in 2010 and 2015. International Council on Clean Transportation. Link to source: https://theicct.org/publication/a-global-snapshot-of-the-air-pollution-related-health-impacts-of-transportation-sector-emissions-in-2010-and-2015/  

Anthopoulos, L. G., & Tzimos, D. N. (2021). Carpooling platforms as smart city projects: a bibliometric analysis and systematic literature review. Sustainability, 13(19), Article 10680. Link to source: https://doi.org/10.3390/su131910680  

Armoogum, J., Borgato, S., Fiorello, D., Garcia, C., Gopal, Y., Maffii, S., Mars, K.-J., Popovska, T., Vincent, V., Bogaert, M., Gayda, S., & Schlemmer, L. (2022). Study on new mobility patterns in European cities: EU-wide passenger mobility survey. IFSTTAR - Institut Français des Sciences et Technologies des Transports, de l’Aménagement et des Réseaux. Link to source: https://doi.org/10.2832/728583  

Bachmann, F., Hanimann, A., Artho, J., & Jonas, K. (2018). What drives people to carpool? Explaining carpooling intention from the perspectives of carpooling passengers and drivers. Transportation Research Part F: Traffic Psychology and Behaviour, 59, 260–268. Link to source: https://doi.org/10.1016/j.trf.2018.08.022  

Beed, R. S., Sarkar, S., Roy, A., Biswas, S. D., & Biswas, S. (2020). A hybrid multi-objective carpool route optimization technique using genetic algorithm and A* algorithm (No. arXiv:2007.05781). arXiv. Link to source: https://doi.org/10.48550/arXiv.2007.05781  

Burnham, A., Gohike, D., Rush, L., Stephens, T., Zhou, Y., Delucchi, M. A., Birky, A., Hunter, C., Lin, Z., Ou, S., Xie, F., Proctor, C., Wiryadinata, S., Liu, N., & Boloor, M. (2021). Comprehensive total cost of ownership quantification for vehicles with different size classes and powertrains. Argonne National Laboratory. Link to source: https://publications.anl.gov/anlpubs/2021/05/167399.pdf 

Cellina, F., Derboni, M., Giuffrida, V., Tomic, U., & Hoerler, R. (2024). Trust me if you can: practical challenges affecting the integration of carpooling in Mobility-as-a-Service platforms. Travel Behaviour and Society, 37, Article 100832. Link to source: https://doi.org/10.1016/j.tbs.2024.100832 

Chan, N. D., & Shaheen, S. A. (2012). Ridesharing in North America: past, present, and future. Transport Reviews, 32(1), 93-112. Link to source: https://doi.org/10.1080/01441647.2011.621557 

Chang, X., Wu, J., Kang, Z., Pan, J., Sun, H., & Lee, D.-H. (2024). Estimating emissions reductions with carpooling and vehicle dispatching in ridesourcing mobility. Npj Sustainable Mobility and Transport, 1(1), Article 16. Link to source: https://doi.org/10.1038/s44333-024-00015-3 

Davis, S. C., & Boundy, R. G. (2022). Transportation energy data book: edition 40. Oak Ridge: Oak Ridge National Laboratory. Link to source: https://tedb.ornl.gov/wp-content/uploads/2022/03/TEDB_Ed_40.pdf 

Dong, X., Liu, H., & Gayah, V. V. (2025). An analytical model of many-to-one carpool system performance under cost-based detour limits. International Journal of Transportation Science and Technology, 18, 80–95. Link to source: https://doi.org/10.1016/j.ijtst.2024.05.007 

European Environment Agency. (2000). Are we moving in the right direction? Indicators on transport and environmental integration in the EU: TERM 2000. Link to source: https://www.eea.europa.eu/publications/ENVISSUENo12/page029.html 

EV Database. (2024). Energy consumption of full electric vehicles. (v5.1.0) [Dataset]. Link to source: https://ev-database.org/cheatsheet/energy-consumption-electric-car  

Fiorello, D., Martino, A., Zani, L., Christidis, P., & Navajas-Cawood, E. (2016). Mobility data across the EU 28 member states: results from an extensive CAWI survey. Transportation Research Procedia, 14, 1104–1113. Link to source: https://doi.org/10.1016/j.trpro.2016.05.181 

Franckx, L. (2024). Increasing the occupancy rates of cars: carrot, stick or both? Case Studies on Transport Policy, 15, Article 101132. Link to source: https://doi.org/10.1016/j.cstp.2023.101132 

Friman, M., Lättman, K., & Olsson, L. E. (2020). Carpoolers’ perceived accessibility of carpooling. Sustainability, 12(21), Article 8976. Link to source: https://doi.org/10.3390/su12218976 

Fulton, L., Brown, A., & Compostella, J. (2020). Generalized costs of travel by solo and pooled ridesourcing vs. privately owned vehicles, and policy implications. UC Office of the President: University of California Institute of Transportation Studies. Link to source: https://doi.org/10.7922/G2WD3XTK 

Gössling, S., Choi, A., Dekker, K., & Metzler, D. (2019). The social cost of automobility, cycling and walking in the European Union. Ecological Economics, 158, 65–74. Link to source: https://doi.org/10.1016/j.ecolecon.2018.12.016 

Gössling, S., Kees, J., & Litman, T. (2022). The lifetime cost of driving a car. Ecological Economics, 194, Article 107335. Link to source: https://doi.org/10.1016/j.ecolecon.2021.107335 

Graba, M., Mamala, J., Bieniek, A., Augustynowicz, A., Czernek, K., Krupińska, A., Włodarczak, S., & Ochowiak, M. (2023). Assessment of energy demand for PHEVs in year-round operating conditions. Energies, 16(14), Article 5571. Link to source: https://doi.org/10.3390/en16145571 

Guarnieri, M., & Balmes, J. R. (2014). Outdoor air pollution and asthma. The Lancet, 383(9928), 1581–1592. Link to source: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(14)60617-6/abstract 

International Energy Agency. (2021). Global fuel economy initiative 2021 data explorer [Data Tool]. Link to source: https://www.iea.org/data-and-statistics/data-tools/global-fuel-economy-initiative-2021-data-explorer 

International Energy Agency. (2024). Global EV outlook 2024. Link to source: https://www.iea.org/reports/global-ev-outlook-2024/outlook-for-emissions-reductions 

Intergovernmental Panel on Climate Change. (2006). Mobile combustion. In S. Eggelston, L. Buendia, K. Miwa, T. Ngara, & K. Tanabe (Eds.), 2006 IPCC guidelines for national greenhouse gas inventories (Vol. 2 Energy, pp. 3.1–3.78). Institute for Global Environmental Strategies (IGES) for the IPCC. Link to source: https://www.ipcc-nggip.iges.or.jp/public/2006gl/pdf/2_Volume2/V2_3_Ch3_Mobile_Combustion.pdf 

International Transport Forum. (2020). Good to go? Assessing the environmental performance of new mobility [Corporate Partnership Board Report]. OECD/ITF Publishing. Link to source: https://www.itf-oecd.org/good-to-go-environmental-performance-new-mobility 

International Transport Forum. (2021). ITF transport outlook 2021. OECD Publishing. Link to source: https://doi.org/10.1787/16826a30-en 

International Transport Forum. (2023). ITF transport outlook 2023. OECD Publishing. Link to source: https://doi.org/10.1787/b6cc9ad5-en 

International Transport Workers’ Federation Global. (2025). Understanding informal transport in Africa. Link to source: https://www.itfglobal.org/en/resources/understanding-informal-transport-in-africa 

Jacobson, S. H., & King, D. M. (2009). Fuel saving and ridesharing in the US: motivations, limitations, and opportunities. Transportation Research Part D: Transport and Environment, 14(1), 14–21. Link to source: https://doi.org/10.1016/j.trd.2008.10.001 

Jalali, R., Koohi-Fayegh, S., El-Khatib, K., Hoornweg, D., & Li, H. (2017). Investigating the potential of ridesharing to reduce vehicle emissions. Urban Planning, 2(2), 26–40. Link to source: https://doi.org/10.17645/up.v2i2.937 

Kerr, G. H., Goldberg, D. L., & Anenberg, S. C. (2021). COVID-19 pandemic reveals persistent disparities in nitrogen dioxide pollution. Proceedings of the National Academy of Sciences, 118(30), Article e2022409118. Link to source: https://doi.org/10.1073/pnas.2022409118  

Kinney, P. L., Gichuru, M. G., Volavka-Close, N., Ngo, N., Ndiba, P. K., Law, A., Gachanja, A., Gaita, S. M., Chillrud, S. N., & Sclar, E. (2011). Traffic impacts on PM2.5 air quality in Nairobi, Kenya. Environmental Science & Policy, 14(4), 369–378. Link to source: https://doi.org/10.1016/j.envsci.2011.02.005

Li, R., Liu, Z., & Zhang, R. (2018). Studying the benefits of carpooling in an urban area using automatic vehicle identification data. Transportation Research Part C: Emerging Technologies, 93, 367–380. Link to source: https://doi.org/10.1016/j.trc.2018.06.012 

Liu, C. Y., & Painter, G. (2012). Travel behavior among Latino immigrants. Journal of Planning Education and Research, 32(1), 62–80. Link to source: https://doi.org/10.1177/0739456X11422070 

Malodia, S., & Singla, H. (2016). A study of carpooling behaviour using a stated preference web survey in selected cities of India. Transportation Planning and Technology, 39(5), 538–550. Link to source: https://doi.org/10.1080/03081060.2016.1174368 

Mamala, J., Graba, M., Bieniek, A., Prażnowski, K., Augustynowicz, A., & Śmieja, M. (2021). Study of energy consumption of a hybrid vehicle in real-world conditions. Eksploatacja i Niezawodność – Maintenance and Reliability, 23(4), 636–645. Link to source: https://doi.org/10.17531/ein.2021.4.6 

Manik, D., & Molkenthin, N. (2020). Topology dependence of on-demand ride-sharing. Applied Network Science, 5(1), Article 49. Link to source: https://doi.org/10.1007/s41109-020-00290-2 

Molina, J. A., Giménez-Nadal, J. I., & Velilla, J. (2020). Sustainable commuting: results from a social approach and international evidence on carpooling. Sustainability, 12(22), Article 9587. Link to source: https://doi.org/10.3390/su12229587 

Pan, S., Yu, W., Fulton, L. M., Jung, J., Choi, Y., & Gao, H. O. (2023). Impacts of the large-scale use of passenger electric vehicles on public health in 30 US. metropolitan areas. Renewable and Sustainable Energy Reviews, 173, Article 113100. Link to source: https://doi.org/10.1016/j.rser.2022.113100 

Pennington, A. F., Cornwell, C. R., Sircar, K. D., & Mirabelli, M. C. (2024). Electric vehicles and health: A scoping review. Environmental Research, 251, Article 118697. Link to source: https://doi.org/10.1016/j.envres.2024.118697 

Requia, W. J., Mohamed, M., Higgins, C. D., Arain, A., & Ferguson, M. (2018). How clean are electric vehicles? Evidence-based review of the effects of electric mobility on air pollutants, greenhouse gas emissions and human health. Atmospheric Environment, 185, 64-77. Link to source: https://doi.org/10.1016/j.atmosenv.2018.04.040 

Rodriguez Mendez, Q., Fuss, S., Lück, S., & Creutzig, F. (2024). Assessing global urban CO2 removal. Nature Cities, 1(6), 413–423. Link to source: https://doi.org/10.1038/s44284-024-00069-x 

Santi, P., Resta, G., Szell, M., Sobolevsky, S., Strogatz, S. H., & Ratti, C. (2014). Quantifying the benefits of vehicle pooling with shareability networks. Proceedings of the National Academy of Sciences, 111(37), 13290–13294. Link to source: https://doi.org/10.1073/pnas.1403657111 

Schaller, B. (2021). Can sharing a ride make for less traffic? Evidence from Uber and Lyft and implications for cities. Transport Policy, 102, 1–10. Link to source: https://doi.org/10.1016/j.tranpol.2020.12.015 

Shaheen, S., Cohen, A., & Bayen, A. (2024). The benefits of carpooling. UC Berkeley: Transportation Sustainability Research Center. Link to source: http://dx.doi.org/10.7922/G2DZ06GF 

Szyszkowicz, M., Kousha, T., Castner, J., & Dales, R. (2018). Air pollution and emergency department visits for respiratory diseases: a multi-city case crossover study. Environmental Research, 163, 263–269. Link to source: https://doi.org/10.1016/j.envres.2018.01.043 

Tomás, R., Fernandes, P., Macedo, J., & Coelho, M. C. (2021). Carpooling as an immediate strategy to post-lockdown mobility: a case study in university campuses. Sustainability, 13(10), Article 5512. Link to source: https://doi.org/10.3390/su13105512 

Tsai, J.-H., Yao, Y.-C., Huang, P.-H., & Chiang, H.-L. (2018). Fuel economy and volatile organic compound exhaust emission for motorcycles with various running mileages. Aerosol and Air Quality Research, 18(12), 3056–3067. Link to source: https://doi.org/10.4209/aaqr.2018.07.0264 

United Nations Development Programme. (2024). A closer look at informal (popular) transportation: an emerging portrait. Link to source: https://www.undp.org/acceleratorlabs/publications/closer-look-informal-popular-transportation-emerging-portrait 

United Nations Economic Commission for Europe. (2023). Road vehicle fleet at 31 December by fuel type, type of vehicle,country and year [Dataset]. Link to source: https://w3.unece.org/PXWeb2015/pxweb/en/STAT/STAT__40-TRTRANS__03-TRRoadFleet/03_en_TRRoadFuelFlt_r.px/ 

Union of Concerned Scientists. (2023). Cars, trucks, buses and air pollution. Link to source: https://www.ucs.org/resources/cars-trucks-buses-and-air-pollution

United States Department of Energy. (2017). Fuel economy guide. Link to source: https://www.fueleconomy.gov/feg/download.shtml

World Health Organization. (2022). Number of registered vehicles. Link to source: https://www.who.int/data/gho/data/indicators/indicator-details/GHO/number-of-registered-vehicles 

Wolfram, P., Tu, Q., Hertwich, E., & Pauliuk, S. (2020). Documentation of the transport-sector model within the RECC model framework v1.0. Link to source: https://doi.org/10.5281/zenodo.3631938 

Yan, L., Luo, X., Zhu, R., Santi, P., Wang, H., Wang, D., Zhang, S., & Ratti, C. (2020). Quantifying and analyzing traffic emission reductions from ridesharing: a case study of Shanghai. Transportation Research Part D: Transport and Environment, 89, Article 102629. Link to source: https://doi.org/10.1016/j.trd.2020.102629 

Zhou, Y., Aeschliman, S., & Gohlke, D. (2020). Affordability of household transportation fuel costs by region and socioeconomic factors. Article ANL/ESD--20/11. Argonne National Laboratory. Link to source: https://doi.org/10.2172/1760477

Credits

Lead Fellows

  • Heather Jones, Ph.D.

Contributors

  • Ruthie Burrows, Ph.D.

  • James Gerber, Ph.D.

  • Daniel Jasper

  • Alex Sweeney

Internal Reviewers

  • Aiyana Bodi

  • Hannah Henkin

  • James Gerber, Ph.D.

  • Amanda D. Smith, Ph.D.

  • Heather McDiarmid, Ph.D.

Effectiveness

Every million pkm shifted from car trips (at the current car occupancy) to fully adopted carpool trips avoids 54.71 t/CO₂‑eq on a 100-yr basis (Table 1) or 55.28 t/CO₂‑eq on a 20-yr basis. 

We found this by calculating baseline car GHG emissions from the global private vehicle fleet, by multiplying the tailpipe emissions intensities of different types of fuels (g/MJ) by the energy intensity of travel by vehicles using those fuels (MJ/vkm) (EV Database, 2024; Graba et al., 2023; International Energy Agency [IEA], 2021; Intergovernmental Panel on Climate Change [IPCC], 2006; ITF, 2020; Mamala et al., 2021; Tsai et al., 2018; U.S. Department of Energy [DOE], 2017). These equaled 112.4 t/CO₂‑eq /million pkm on a 100-year basis (113.6 t/CO₂‑eq /million pkm on a 20-year basis). We multiplied these emissions by the average occupancy of each vehicle type (ITF, 2020) to produce an average emissions intensity for CO₂, methane, and nitrous oxide for every vehicle type. We then combined these into a global weighted average based on the percentage of each type of vehicle (electric, hybrid and fossil fuel–powered) in the global fleet (United Nations Economic Commission for Europe [UNECE], 2023). The result is a car baseline for the global average emissions intensity of passenger cars. 

We then used the global GHG emissions intensity to calculate carpool emissions based on the carpool car occupancy and subtracted them from the baseline car occupancy to determine emissions avoided.

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Table 1. Effectiveness at reducing emissions.

Unit: t CO₂‑eq (100-year basis)/million pkm avoided

25th percentile 48.77
Mean 57.72
Median (50th percentile) 54.71
75th percentile 66.72
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Cost

It costs US$0.34/pkm to run a car (at current global average occupancy of 1.5 (ITF, 2020)), including car purchase and maintenance costs, fuel, etc., but excluding indirect costs such as the value of time spent driving a car. It costs US$0.17/pkm for a fully adopted carpool ride (car occupancy of 3). This is a savings of US$170,662/million pkm (AAA, 2022; Burnham et al., 2021; Gössling et al., 2019, 2022). These direct financial costs do not include estimates of additional fuel needed due to additional weight of passengers or additional mileage due to pick up and drop off.

This amounts to savings of US$3,119 t CO₂‑eq on a 100-year basis (Table 2) or US$3,087 t CO₂‑eq avoided emissions on a 20-year basis. 

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Table 2: Cost per unit climate impact.

Unit: US$ (2023) per t CO₂‑eq (100-year basis)

Median -3,119
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Learning Curve

Carpooling is a behavioral solution, so its performance can improve over time through scaling, experience, and social normalization but not at a quantifiable learning rate. 

The most important mechanism for increasing carpooling is behavioral familiarity. As people become accustomed to carpooling, social and psychological barriers decline (Adelé & Dionisio, 2020; Malodia & Singla, 2016). Another mechanism that can improve carpooling performance is platform optimization. As apps and algorithms improve, matching riders becomes faster and more efficient (Beed et al., 2020; Santi et al., 2014). Network effects can also improve performance. More users increase the chance of shared trips, reducing wait times and detours (Dong et al., 2025; Manik & Molkenthin, 2020). Over time, through policy support and incentives, cities may develop dedicated lanes, subsidies, or integration with public transport, improving performance (Anthopoulos & Tzimos, 2021; Bachmann et al., 2018).

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Speed of Action

Speed of action refers to how quickly a climate solution physically affects the atmosphere after it is deployed. This is different from speed of deployment, which is the pace at which solutions are adopted.

At Project Drawdown, we define the speed of action for each climate solution as emergency brake, gradual, or delayed.

Increase Carpooling is a GRADUAL climate solution. It has a steady, linear impact on the atmosphere. The cumulative effect over time builds as a straight line.

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Caveats

Carpooling often falters due to the difficulty of aligning multiple participants’ schedules. Commuters face mismatched work hours, unexpected delays, or shifting routines, raising stress and reducing reliability. Comfort and privacy are additional deterrents because many travelers prefer the autonomy and personal space of driving alone. Trust and safety concerns also play a major role – riding with strangers raises worries about reliability and personal security (Cellina et al., 2024).

Accessibility further complicates adoption. In low-density areas, the limited pool of potential passengers makes ride-matching impractical, while in urban areas cultural resistance and ingrained travel habits hinder uptake (Friman et al., 2020). Finally, digital divides restrict participation in app-based systems, excluding those without reliable smartphone or internet access.

When carpooling uses platform operators it generates some emissions from server use, data processing, and administrative activities. These operational emissions are small compared to the reductions achieved.

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Current Adoption

The current car occupancy is 1.5 persons per car (ITF, 2020). Approximately 2 billion cars are in use worldwide (WHO, 2022). To convert this number into pkm traveled by car, we needed to determine the average pkm that each passenger car travels per year. Using population-weighted data from several countries, we found that the average car carries 1.5 people and travels about 19,500 vkm/yr, or an average of 29,250 pkm/yr. Multiplying this by the number of cars in use gives the total travel distance by cars with the current occupancy. This corresponds to about 59 trillion pkm traveled by car worldwide each year. 

Current car occupancy is from a global average (ITF, 2020), and adoption trend and achievable adoption are based on reported car occupancy from Belgium, Canada, China, Denmark, France, Germany, India, Italy, Japan, Latvia, Romania, United Kingdom, United States, and the European Union (Armoogum et al., 2022; Davis & Boundy, 2022; European Environment Agency [EEA], 2000; Fiorello et al., 2016; Franckx, 2024; Wolfram et al., 2020).

Since 1.5 persons per car is the current occupancy average, we define adoption as the increase in avoided pkm/yr as a result of increased occupancy above 1.5. For this reason, current adoption is represented as zero (Table 3), and potential adoption in Table 6 is the increase in million pkm avoided each year.

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Table 3. Current (2024) adoption level.

Unit: million pkm/yr avoided above current levels

Median, or population-weighted mean 0
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Adoption Trend

Average world car occupancy has been flat since the 1990s after declining from higher occupancy in the 1970s. Therefore, we set the adoption trend to zero (Table 4). 

For example, car occupancy in the United States decreased from 1.9 in 1977 to 1.7 in 2009 and held steady at 1.7 in 2017 (Davis & Boundy, 2022). The European Union car occupancy decreased from 2.0 in 1970 to 1.5 in 1990, where it has held steady (EEA, 2000). Despite the emergence of carpooling platforms like BlaBlaCar, Carpoolworld, Liftshare, Participation, Lyft, and Uber Share (formerly known as) Uber Pool, overall car occupancy has remained largely unchanged. These advances have improved convenience and access, but structural barriers such as travel time mismatches, privacy preferences, and urban sprawl continue to limit adoption. 

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Table 4. Adoption trend (2023–2024).

Unit: million pkm/yr avoided above current levels

Median, or population-weighted mean 0
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Adoption Ceiling

The adoption ceiling for increasing carpooling is equal to the pkm/yr avoidance if every car trip is a fully adopted carpool trip instead of the baseline adoption. Using a population-weighted mean of the average distance (in pkm) traveled per car annually, this translates to about 19.71 trillion pkm/yr avoided (Table 5). We assume that all of these trips can be made by carpool, regardless of purpose or distance. 

Romania reports a car occupancy of 2.7 (Fiorello et al., 2016), more than double the multi-occupancy of countries like the United States, where occupancy has remained around 1.5–1.7 for decades (Davis & Boundy, 2022; ITF, 2020; Wolfram et al., 2020). This demonstrates that significantly higher occupancy is not only possible but already practiced in certain contexts.

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Table 5. Adoption ceiling: upper limit for adoption level. 

Unit: million pkm/yr avoided above current levels

Median, or population-weighted mean 19,710,000
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Achievable Adoption

Current car occupancy is useful for identifying globally achievable occupancy (Armoogum et al., 2022; Davis & Boundy, 2022; EEA, 2000; Fiorello et al., 2016; Franckx, 2024; ITF, 2023; Wolfram et al., 2020). 

To determine the high achievable level of carpool adoption, we assumed that every country could reach the highest adoption for any country. Romania had the highest reported average car occupancy at 2.7 (Fiorello et al., 2016) in 2016. We therefore set our high adoption at 2.7. This corresponds to 17.5 trillion pkm/yr avoided (Table 6). 

To identify a lower feasible level of carpool adoption, we took the historical average reported estimates for global car occupancy. This corresponds to a car occupancy of 1.7, or 5 trillion pkm/yr avoided by carpooling (Table 6).

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Table 6. Range of achievable adoption levels.

Unit: million pkm/yr avoided above current levels

Current adoption 0.00
Achievable – low 4,638,000
Achievable – high 17,520,000
Adoption ceiling (physical limit) 19,710,000
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If average car occupancy globally reaches the low end of the achievable range of 1.7, it will avoid 0.254 Gt CO₂‑eq/yr GHG emissions (100-yr basis) over the current state.

If average car occupancy reaches 2.7 (the high end of the achievable range), it will avoid 0.959 Gt CO₂‑eq/yr GHG emissions (100-yr basis) over the current state.

If carpooling is fully adopted at a global average car occupancy of 3.0 (adoption ceiling), it would avoid 1.079 Gt CO₂‑eq/yr GHG emissions on a 100-yr basis.

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Table7. Climate impact at different levels of adoption above current levels.

Unit: Gt CO₂‑eq per year avoided, 100-yr basis

Current adoption 0.000
Achievable – low 0.254
Achievable – high 0.959
Adoption ceiling (physical limit) 1.079
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Additional Benefits

Income and Work

Carpooling can save money through shared travel costs between passengers (Chan & Shaheen, 2012; Molina et al., 2020; Shaheen et al., 2024). One study estimated that adding one passenger for every 100 vehicles, excluding any additional travel, could avoid 800–820 million gallons of gasoline each year in the United States (Jacobson & King, 2009). Actual cost savings would depend on the price of gasoline and any additional travel required to pick up passengers. These savings may be especially beneficial for low-income households (Zhou et al., 2020). 

Health

Tailpipe emissions from internal combustion engine cars are associated with asthma, lung cancer, increased emergency department visits for respiratory disease, and increased mortality (Anenberg et al., 2019; Guarnieri & Balmes, 2014; Pan et al., 2023; Pennington et al., 2024; Requia et al., 2018; Szyszkowicz et al., 2018). Urban areas, and often those in low- and middle-income countries, experience disproportionately higher vehicle emissions and higher health impacts (Anenberg et al., 2019; Kinney et al., 2011). By reducing vehicle miles traveled, carpooling can reduce vehicle emissions and associated health impacts (Shaheen et al., 2024). A reduction in vehicle miles traveled can improve traffic congestion and road safety (Shaheen et al., 2024). Carpooling is associated with several psychological benefits, including improved sociability and reduced commute stress (Chan & Shaheen, 2012; Molina et al., 2020).

Equality

Communities that are lower income or rich in racial and ethnic minorities tend to be located near highways and major traffic corridors, and so are disproportionately exposed to air pollution (Kerr et al., 2021). Carpooling can reduce the impacts of air pollution on these populations (Shaheen et al., 2024). In the United States, carpooling can increase the accessibility of transportation for low-income, racial and ethnic minority, or immigrant populations who cannot afford personal vehicles or cannot attain driver’s licenses (Liu & Painter, 2012; Shaheen et al., 2024). Enhanced access to transportation broadly is important for increasing economic equality by providing households with income-earning opportunities.

Air Quality

Tailpipe emissions from internal combustion engine cars contain particulate matter, sulfur oxides, nitrous oxides, carbon monoxide, and volatile organic compounds (Union of Concerned Scientists, 2023). Carpooling is associated with reduced energy consumption and reduced emissions from internal combustion engine cars (Molina et al., 2020; Shaheen et al., 2024). Carpooling can reduce traffic congestion, though the magnitude of this reduction is uncertain (Chan & Shaheen, 2011). One study in Langfang, China, found that carpooling can reduce trips during the morning and evening commuting hours, reducing vehicle volume and increasing travel speeds for both carpooling and non-carpooling cars (Li et al., 2018).

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Risks

Carpooling services could induce additional car use, especially if they offer convenience and low costs that attract people who would otherwise not have traveled or would have used lower-emission modes. This is a form of the rebound effect, where efficiency gains are offset by increased travel demand.

Carpooling may raise safety and security concerns, particularly in informal or app-based systems where passengers share rides with strangers. Concerns around personal safety, especially for women and marginalized groups, can limit adoption or require regulatory oversight.

Promoting carpooling without coordination with public transport policy could erode ridership on bus or rail systems. This could weaken investment in public transit and make systems less viable, especially in low-density or suburban areas.

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Interactions with Other Solutions

Reinforcing

Carpooling reinforces non-car transportation modes by extending reach, offering first- and last-mile connections, and providing flexible options where fixed-route services are limited.

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Carpooling reinforces the benefits of electric and hybrid cars by maximizing each vehicle’s efficiency, spreading battery and fuel savings across more passengers, and further reducing per-capita emissions.

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Competing 

Carpooling, electric bicycles, and public transit compete for pkm. Consequently, increased use of carpooling could reduce kilometers traveled using public transit or electric bicycles. 

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Dashboard

Solution Basics

million pkm avoided

t CO₂-eq (100-yr)/unit
048.7754.71
units/yr
Current 0 04.638×10⁶1.752×10⁷
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current Not Determined 0.2540.959
US$ per t CO₂-eq
-3,119
Gradual

CO₂ , CH₄, N₂O, BC

Trade-offs

Carpooling reduces the number of vehicles on the road per trip but still relies on cars rather than shifting demand toward lower-impact modes such as public transit or nonmotorized transportation.

Carpooling requires changes in user behavior and social norms, rather than technological innovation. While this avoids the environmental and financial costs of new infrastructure or vehicles, it can be challenging because it depends on people being willing to alter their travel habits, coordinate with others, and potentially sacrifice convenience or privacy.

The extent of emission reduction depends on how many people share the ride and whether the carpool replaces trips that would have otherwise been made using more sustainable transport modes (e.g., walking, cycling, or public transport).

The environmental benefits of carpooling vary based on travel behavior and context. If carpooling fills otherwise empty seats in cars already on the road, it can be highly efficient. However, if it results in route detours or deadheading or if people shift from using transit to carpooling, the net benefit may be smaller or even negative.

Carpooling can reduce the overall number of cars needed for transportation, which in turn can decrease congestion and urban parking demand. However, this benefit is limited if carpooling is only used during peak hours or if it competes with active or public transport options.

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Action Word
Increase
Solution Title
Carpooling
Classification
Highly Recommended
Lawmakers and Policymakers
  • Incorporate carpooling into government transportation policy; facilitate carpooling systems, encourage and incentivize employee participation, and ensure leaders are committed to and participate in carpooling.
  • Create dedicated coordinating bodies across government agencies, businesses, and the public to develop carpooling systems; conduct regular movement planning to identify changes in participation and opportunities to increase adoption.
  • Reduce the number of fleet vehicles and increase passenger capacity as much as possible.
  • Use a combination of policies that both incentivizes carpooling and disincentivizes single occupancy trips.
  • Implement disincentives for driving such as congestion tolls, fuel taxes, and smog fees (based on how much a car pollutes and is driven).
  • Implement targeted support measures such as carpool lanes, the option to use bus lanes, and dedicated parking spots.
  • Deploy financial incentives such as tax breaks, reduced or waived toll fare, and subsidies for carpoolers.
  • Fund public carpooling schemes or subsidize private carpooling initiatives.
  • Fund free “guaranteed ride home” initiatives for carpoolers via public transit or private taxis/rideshares.
  • Integrate private and individual carpooling initiatives into Mobility as a Service (MaaS) systems, allowing for seamless transfers between public and private transportation systems.
  • Clarify legal structures around carpooling to allow drivers to accept reimbursement while remaining noncommercial operators; ensure the maximum allowable fees are enough to incentivize drivers while not outcompeting public transportation.
  • Develop regulatory structures for web-based carpooling applications that focus on minimum standards related to security, data privacy, and consumer protection; mandate user verification, create a registration system for users, and offer ongoing support for safety and security.
  • Encourage carpooling platforms to enact data-sharing agreements; mandate trip details be shared with regulatory agencies, and cross-reference user identities with national databases to screen for relevant criminal backgrounds.
  • Work with universities, businesses, and other large institutions to encourage carpooling schemes; engage in public-private partnerships with carpooling matching services to increase adoption.
  • Report on success of carpooling efforts including number of drivers and users, fuel reductions, and emissions avoidance.
  • Develop carpooling awareness campaigns focusing on internally motivating factors such as money saved, health benefits, reduced pollution, social connection, and lifestyle sustainability.

Further information:

Practitioners
  • Conduct mobility planning with local government agencies and the public to optimize routes and decrease waiting times.
  • Cluster pick-up and drop-off zones near freeways, residential areas, parking, public transit, and/or popular commercial areas – ensuring well-lit environments.
  • Host events for carpoolers, create in-person carpooling clubs, and start social media groups for carpoolers to build trust.
  • Offer incentives for joining and participating in carpooling programs; collaborate with local government and businesses to offer incentives.
  • Create web applications and websites for matching services that are easy to use, have a professional user interface, and have built-in chat features to build trust for participants.
  • Integrate carpooling initiatives into MaaS systems, allowing for seamless transfers between public and private transportation systems.
  • Use a carpool application screening process to increase trust and safety; gather information on motivations for carpooling to help match like-minded participants.
  • Allow drivers to set their own fees (within a maximum allowable range) or to waive fees for passengers; allow for nonmonetary compensation.
  • Ensure drivers and passengers have public profiles with ratings to allow participants to select drivers and passengers; create filters for categories such as gender, preferred levels of socialization, trip purpose, etc; allow for women-only trips.
  • Designate clear responsibilities for both drivers and passengers.
  • Encourage participants to socialize with each other and to share their experiences and insights with their community.
  • Collect feedback from participants and update web-based matching applications to accommodate local preferences and culture.
  • Create features on web applications that show how much money, fuel, and emissions participants have avoided by carpooling; create competitions for biggest avoiders and most active participants; develop gamification methods appropriate for the local context.
  • Ensure applications offer real-time support and ride tracking to enhance safety and trust.
  • Collaborate with insurance companies to offer carpooling policies that cover injury, property damage, and liability during trips.
  • Develop carpooling awareness campaigns focusing on factors such as money saved, health benefits, reduced pollution, social connection, and lifestyle sustainability.

Further information:

Business Leaders
  • Develop company policies promoting carpooling; communicate to employees and the public how they support broader company goals; ensure leadership is committed and participates in carpooling.
  • Develop systems to track and plan fleet routes that encourage carpooling.
  • Reduce the number of fleet vehicles and increase passenger capacity.
  • Ask staff, including senior management, to identify barriers and opportunities for carpooling.
  • Work with large institutions such as universities, businesses, and public agencies to coordinate wider carpooling schemes; partner with carpooling matching services.
  • Report on success of carpooling efforts, including number of drivers and users, fuel reductions, and emissions avoidance.
  • Pay a cash bonus or offer pretax benefits for staff who carpool or take public transportation.
  • If your company offers employees courtesy rides via rideshare platforms, incentivize carpooling by covering 100% of carpool trips but only a portion of individual trips.
  • Offer other perks for employees who carpool such as preferred parking.
  • Partner with local and/or private carpooling initiatives to offer promotional incentives such as gift cards or discounts.
  • Create and distribute educational materials for employees on carpooling and commuting best practices.
  • Partner with, support, and/or donate to carpooling infrastructure investments and awareness campaigns.
  • Advocate for better public carpooling policies and integrated services with public transit systems.

Further information:

Nonprofit Leaders
  • Develop policies promoting carpooling; communicate to employees and the public how they support broader organizational goals; ensure leadership is committed and participates in carpooling.
  • Develop systems to track and plan fleet routes that encourage carpooling.
  • Reduce the number of vehicles and increasing passenger capacity as much as possible.
  • Ask staff, including senior management to identify barriers and opportunities for carpooling.
  • Report on success of carpooling efforts including number of drivers and users, fuel reductions, and emissions avoided.
  • Pay a cash bonus or provide pretax benefits for staff who carpool (or take public transportation).
  • Offer other perks for employees who carpool such as preferred parking.
  • Administer carpooling schemes using web-based applications; expand carpooling services to underserved communities by creating matching services or subsidizing participation.
  • Work with large institutions such as universities, businesses, and public agencies to coordinate wider carpooling schemes; partner with carpooling matching services.
  • Advocate for better public carpooling regulations and services with local officials.
  • Help design local regulations to clarify legal classification for carpool drivers or provide means for assessments, data collection, citizen participation, and other steps in the policymaking process.
  • Host or support carpooling clubs, events, social media groups, and other strategies for promoting carpooling.
  • Create, support, or partner with carpooling awareness campaigns that focus on motivating factors such as money saved, health benefits, reduced pollution, social connection, and a sustainable lifestyle.

Further information:

Investors
  • Encourage employees to carpool.
  • Encourage portfolio companies to incentivize, provide, or promote carpooling opportunities and infrastructure, and to share fleet management plans.
  • Invest in companies that are improving the comfort, accessibility, and cost of carpooling infrastructure.
  • Invest in companies that provide or are developing web-based carpooling matching algorithms or services.
  • Invest in companies that provide MaaS and integration with existing mobility services.
  • Invest in carpooling models, supportive technology, and infrastructure.
  • Deploy capital to efforts that increase safety, trust, and convenience of web-based applications that support carpooling, such as methods of encryption and ways to integrate services into public transportation systems.

Further information:

Philanthropists and International Aid Agencies
  • Develop organizational policies promoting carpooling; communicate to employees and the public how they support broader organizational goals; ensure leadership is committed and participates in carpooling.
  • Develop systems to track and plan fleet routes to enable carpooling.
  • Reduce the number of fleet vehicles and increase passenger capacity.
  • Award grants to organizations developing or organizing carpooling services and/or advocating for improved carpooling regulations; fund projects that pilot carpooling in underserved areas and transit deserts.
  • Invest in companies that provide or are developing web-based carpooling matching services or integration with public transit infrastructure and existing mobility services.
  • Deploy capital to efforts that increase safety, trust, and convenience of web-based applications that support carpooling such as methods of encryption and ways to integrate services into public transportation systems.
  • Administer carpooling schemes using web-based applications; expand carpooling services to underserved communities by creating matching services or subsidizing participation.
  • Advocate for better public carpooling policies and integrated services with public transit systems.
  • Work with large institutions such as universities, businesses, and public agencies to coordinate wider carpooling schemes; partner with carpooling matching services.
  • Create, support, or partner with carpooling awareness campaigns that focus on motivating factors such as money saved, health benefits, reduced pollution, social connection, and a sustainable lifestyle.
  • Host or support carpooling clubs, events, social media groups, and other strategies for promoting carpooling.
  • Improve and finance local infrastructure such as high-occupancy vehicle (HOV) lanes and carpooling capacity.
  • Help design local regulations to clarify legal classification for carpool drivers or provide means for assessments, data collection, citizen participation, and other steps in the policymaking process.
  • Develop carpooling awareness campaigns focusing on motivating factors such as money saved, health benefits, reduced pollution, social connection, and lifestyle sustainability.

Further information:

Thought Leaders
  • Lead by example and carpool regularly.
  • Share information on carpooling initiatives.
  • Develop carpooling awareness campaigns focusing on motivating factors such as money saved, health benefits, reduced pollution, social connection, and lifestyle sustainability.
  • Help design regulations to clarify legal classification for carpool drivers or provide means for assessments, data collection, citizen participation, and other steps in the policymaking process.
  • Advocate for better public carpooling regulations and services with local officials.
  • Conduct local market research on specific demographics and professions to understand what incentives or disincentives will drive adoption.
  • Host events for carpoolers, create in-person carpooling clubs, and start social media groups for local carpoolers to build trust and community offline.

Further information:

Technologists and Researchers
  • Develop applications that match users with carpooling opportunities based on routes, time, and location, and integrate them with local public transportation and other mobility services.
  • Use data from mobile phones, GPS trackers, and social networking to identify travelers with similar patterns and suggest carpooling routes.
  • Develop safety protocols for data usage in carpooling apps; create options for women-only rides.
  • Research the impact of incentives and disincentives on modal choice in specific metropolitan areas, regions, and countries; identify the most effective means of increasing adoption.
  • Research what impacts trust between users and carpooling platforms and between users and drivers; investigate differences in trust by local demographic characteristics; examine mechanisms for increasing trust and safety for users.
  • Research the impact of vehicle ownership on willingness to carpool, and how participating as both a driver and passenger can influence adoption.
  • Develop ways to maintain data privacy for participants while also allowing for transparency and safety; examine applications of encryption methods such as homomorphic encryption.

Further information:

Communities, Households, and Individuals
  • Carpool regularly and encourage your household, neighbors, and community to carpool when feasible.
  • Take advantage of financial incentives such as tax breaks, subsidies, or grants for carpooling.
  • Share information on local carpooling initiatives with your community.
  • Host events for carpoolers, create carpooling clubs, and start social media groups for local carpoolers to build trust offline.
  • Advocate for better public carpooling regulations and services with local officials.
  • Encourage employers and local businesses to provide incentives for carpooling.
  • Participate in or develop carpooling awareness campaigns focusing on motivating factors such as money saved, health benefits, reduced pollution, social connection, and lifestyle sustainability.

Further information:

Sources
Evidence Base

Consensus of effectiveness in decarbonizing the transport sector: Mixed

There is a high level of consensus among major organizations working in the area of climate solutions that carpooling can substantially reduce GHG emissions. Fewer vehicles mean less fuel burned per pkm. However, research on the real-world effectiveness of carpooling is mixed. Carpooling has remained largely flat for decades despite policy incentives and the advent of ride-sharing platforms, limiting its overall contribution to emission reductions. Additionally, rebound effects may occur or if carpoolers would otherwise have taken public transit, walked, or biked, thereby offsetting some emission avoidance. 

Globally, cars and vans were responsible for 3.8 Gt CO₂‑eq emissions in 2023 – more than 60% of road transport emissions (IEA, 2024).

Large-scale carpooling can significantly reduce fuel consumption and emissions, with studies in Shanghai showing reductions of 15–23% depending on adoption scenarios, and additional efficiency gains from improved traffic flow (Yan et al., 2020).

Carpooling can substantially reduce vehicle activity. Jalali et al. (2017) found up to a 24% decrease in total distance driven and a 40% reduction in vehicle trips under optimal conditions in Changsha, China, which translates into daily CO₂ emission reductions of around 4 tons.

Simulations on university campuses showed potential reductions of 5% in CO₂ and 7% in nitrous oxide emissions, alongside a 7% increase in average speed and an 8% reduction in travel time with increased adoption of carpooling (Tomas et al., 2021).

The results presented in this document summarize findings from 15 reviews and meta-analyses and 24 original studies reflecting current evidence from 52 countries. We recognize this limited geographic scope creates bias, and hope this work inspires research and data sharing on this topic in underrepresented regions.

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Updated Date

Improve Nonmotorized Transportation

Submitted by Drawdown Admin on
Sector
Transportation
Mode
Cut Emissions
Cluster
Shift to Alternatives
Image
Many people in a crosswalk viewed from above
Coming Soon
Off
Summary

We define Improve Nonmotorized Transportation as increasing any form of travel that does not use a motor or engine. In theory, this includes a huge range of transportation modes, including horses, cross-country skis, sailboats, hand-operated rickshaws, and animal-drawn carriages. In practice, pedestrian travel and cycling account for most nonmotorized utilitarian passenger travel.

Income & work,Health
Nature protection,Air quality
Description for Social and Search
Improve Nonmotorized Transportation is a Highly Recommended climate solution. Walking and cycling reduce GHG emissions, promote health, and require minimal infrastructure.
Overview

Travel shifted from motorized to nonmotorized transportation saves GHG emissions – mostly CO₂, but also small amounts of nitrous oxide and methane (Center for Sustainable Systems, 2023) – that a fossil fuel-powered car would otherwise emit. 

We divided nonmotorized transportation into three subcategories: 1) pedestrian travel, including walking and the use of mobility aids such as wheelchairs; 2) private bicycles owned by the user, meaning that they are typically used for both the outgoing and return legs of a trip; and 3) shared bicycles, which are sometimes used for only one leg of a trip and so have to be repositioned by other means.

Pedestrian travel

Pedestrian travel (including both walking and travel using mobility aids such as wheelchairs) has the advantage of being something that most people can do and often does not require special equipment or dedicated infrastructure (although some infrastructure, such as sidewalks, can be helpful). Pedestrian travel is 81.7% of global urban nonmotorized pkm. 

Private bicycles

Private bicycles cost money and require maintenance but enable travel at much faster speeds and therefore longer distances. Private bicycles are 13% of global urban nonmotorized pkm.

Shared bicycles 

Shared bicycles eliminate the financial overhead of bicycle ownership, but usually only permit travel within specific urban areas and sometimes between established docking stations. Shared bicycles are 5.1% of global urban nonmotorized pkm. 

Note that we did not include electric bicycles in this analysis. Electric bicycles are analyzed as a separate solution.

While improving nonmotorized transportation can be a valuable climate solution virtually anywhere, we limit our analysis to cities due to the high number of relatively short-distance trips and the abundance of available data compared with rural locations.

The fuel for cycling and pedestrian travel is the food the traveler eats. When the traveler metabolizes the food, they produce CO₂. Some studies factor the GHG emissions produced by the added metabolism required by nonmotorized transportation into its climate impact because of the emissions that come from the food system (Mizdrak et al., 2020). This is controversial, however, because it is unclear whether pedestrians and cyclists have a higher calorie intake than people who travel in other ways (Noussan et al., 2022). Furthermore, additional food eaten to fuel physical labor is not typically counted in life-cycle analyses. This analysis, therefore, does not consider the upstream climate impacts of food calories that fuel cycling, pedestrian travel, driving, or any other activity.

AAA. (2024). AAA’s Your driving costs – AAA Exchange. Link to source: https://exchange.aaa.com/automotive/aaas-your-driving-costs/

Adamos, G., Nathanail, E., Theodoridou, P., & Tsolaki, T. (2020). Investigating the effects of active travel in health and quality of life. Transport and Telecommunication Journal, 21(3), 221–230. Link to source: https://doi.org/10.2478/ttj-2020-0018

Blondiau, T., van Zeebroeck, B., & Haubold, H. (2016). Economic benefits of increased cycling. Transportation Research Procedia, 14, 2306–2313. Link to source: https://doi.org/10.1016/j.trpro.2016.05.247

Bonilla-Alicea, R. J., Watson, B. C., Shen, Z., Tamayo, L., & Telenko, C. (2020). Life cycle assessment to quantify the impact of technology improvements in bike-sharing systems. Journal of Industrial Ecology, 24(1), 138–148. Link to source: https://doi.org/10.1111/jiec.12860

Bopp, M., Sims, D., & Piatkowski, D. (2018). Benefits and risks of bicycling. 21–44. Link to source: https://doi.org/10.1016/B978-0-12-812642-4.00002-7

Brand, C., Dons, E., Anaya-Boig, E., Avila-Palencia, I., Clark, A., de Nazelle, A., Gascon, M., Gaupp-Berghausen, M., Gerike, R., Götschi, T., Iacorossi, F., Kahlmeier, S., Laeremans, M., Nieuwenhuijsen, M. J., Pablo Orjuela, J., Racioppi, F., Raser, E., Rojas-Rueda, D., Standaert, A., … Int Panis, L. (2021). The climate change mitigation effects of daily active travel in cities. Transportation Research Part D: Transport and Environment, 93, 102764. Link to source: https://doi.org/10.1016/j.trd.2021.102764

Burnham, A., Gohlke, D., Rush, L., Stephens, T., Zhou, Y., Delucci, M. A., Birky, A., Hunter, C., Lin, Z., Ou, S., Xie, F., Proctor, C., Wiryadinata, S., Liu, N., & Boloor, M. (2021). Comprehensive total cost of ownership quantifications for vehicles with different size classes and powertrains (ANL/ESD-21/4). Argonne National Laoratory. Link to source: https://publications.anl.gov/anlpubs/2021/05/167399.pdf

Center for Sustainable Systems. (2023). Personal transportation factsheet (CSS01-07). University of Michigan. Link to source: https://css.umich.edu/publications/factsheets/mobility/personal-transportation-factsheet

Christensen, L., & Vázquez, N. S. (2013). Post-harmonised european national travel surveys. Proceedings from the Annual Transport Conference at Aalborg University, 20(1), Article 1. Link to source: https://doi.org/10.5278/ojs.td.v1i1.5701

CityTransit Data. (2025). A global analysis of transit data. CityTransit Data. Link to source: https://citytransit.uitp.org/ 

DeMaio, P. (2009). Bike-sharing: History, impacts, models of provision, and future. Journal of Public Transportation, 12(4), 41–56. Link to source: https://doi.org/10.5038/2375-0901.12.4.3

Department for Transport. (2024). Department for transport statistics NTS 0101: Trips, distance travelled, and time taken: England, 1972 onwards [Dataset]. Link to source: https://app.powerbi.com/view?r=eyJrIjoiMGE2YTQ5YTMtMDkwNC00MjBmLWFkNjUtMjBjZjUzZWU0ZjNmIiwidCI6IjI4Yjc4MmZiLTQxZTEtNDhlYS1iZmMzLWFkNzU1OGNlNzEzNiIsImMiOjh9

European Commission. (2019). Handbook on the external costs of transport. European Commission. Link to source: https://cedelft.eu/wp-content/uploads/sites/2/2021/03/CE_Delft_4K83_Handbook_on_the_external_costs_of_transport_Final.pdf

Federal Highway Administration. (2022). Summary of travel trends: 2022 National Household Travel Survey. US Department of Transportation. Link to source: https://nhts.ornl.gov/assets/2022/pub/2022_NHTS_Summary_Travel_Trends.pdf

Fishman, E., & Schepers, P. (2016). Global bike share: What the data tells us about road safety. Journal of Safety Research, 56, 41–45. Link to source: https://doi.org/10.1016/j.jsr.2015.11.007 

Flanagan, E., Lachapelle, U., & El-Geneidy, A. (2016). Riding tandem: Does cycling infrastructure investment mirror gentrification and privilege in Portland, OR and Chicago, IL? Research in Transportation Economics, 60, 14–24. Link to source: https://doi.org/10.1016/j.retrec.2016.07.027

Glazener, A., & Khreis, H. (2019). Transforming our cities: Best practices towards clean air and active transportation. Current Environmental Health Reports, 6(1), 22–37. Link to source: https://doi.org/10.1007/s40572-019-0228-1

Gössling, S., Neger, C., Steiger, R., & Bell, R. (2023). Weather, climate change, and transport: A review. Natural Hazards, 118(2), 1341–1360. Link to source: https://doi.org/10.1007/s11069-023-06054-2

Gössling, S., Choi, A., Dekker, K., & Metzler, D. (2019). The social cost of automobility, cycling and walking in the European Union. Ecological Economics, 158, 65–74. Link to source: https://doi.org/10.1016/j.ecolecon.2018.12.016

Günther, M., & Krems, J. (2022). The liveable city—How effective planning for infrastructure and personal mobility can improve people’s experiences of urban life. 13th International Conference on Applied Human Factors and Ergonomics (AHFE 2022). Link to source: https://doi.org/10.54941/ahfe1002372

International Transport Forum. (2020). Good to go? Assessing the environmental performance of new mobility (Corporate Partnership Board). OECD. Link to source: https://www.itf-oecd.org/sites/default/files/docs/environmental-performance-new-mobility.pdf

International Transport Forum. (2021). ITF Transport Outlook 2021. OECD. Link to source: https://www.itf-oecd.org/itf-transport-outlook-2021 

Hymel, K. M., Small, K. A., & Dender, K. V. (2010). Induced demand and rebound effects in road transport. Transportation Research Part B: Methodological, 44(10), 1220–1241. Link to source: https://doi.org/10.1016/j.trb.2010.02.007

IPCC. (2023). Renewable energy sources and climate change mitigation—IPCC. Link to source: https://www.ipcc.ch/report/renewable-energy-sources-and-climate-change-mitigation/

Litman, T. (2011). Environmental reviews & case studies: Why and how to reduce the amount of land paved for roads and parking facilities. Environmental Practice, 13(1), 38–46. Link to source: https://doi.org/10.1017/S1466046610000530

Litman, T. (2024). Evaluating active transport benefits and costs: Guide to valuing walking and cycling improvements and encouragement programs. Victoria Transport Policy Institute. Link to source: https://www.vtpi.org/nmt-tdm.pdf

Mailloux, N. A., Henegan, C. P., Lsoto, D., Patterson, K. P., West, P. C., Foley, J. A., & Patz, J. A. (2021). Climate solutions double as health interventions. International Journal of Environmental Research and Public Health, 18(24), Article 24. Link to source: https://doi.org/10.3390/ijerph182413339

Mizdrak, A., Cobiac, L. J., Cleghorn, C. L., Woodward, A., & Blakely, T. (2020). Fuelling walking and cycling: Human powered locomotion is associated with non-negligible greenhouse gas emissions. Scientific Reports, 10(1), Article 1. Link to source: https://doi.org/10.1038/s41598-020-66170-y

Montoya-Torres, J., Akizu-Gardoki, O., & Iturrondobeitia, M. (2023). Measuring life-cycle carbon emissions of private transportation in urban and rural settings. Sustainable Cities and Society, 96, 104658. Link to source: https://doi.org/10.1016/j.scs.2023.104658

Mueller, N., Rojas-Rueda, D., Cole-Hunter, T., de Nazelle, A., Dons, E., Gerike, R., Götschi, T., Int Panis, L., Kahlmeier, S., & Nieuwenhuijsen, M. (2015). Health impact assessment of active transportation: A systematic review. Preventive Medicine, 76, 103–114. Link to source: https://doi.org/10.1016/j.ypmed.2015.04.010

Münzel, T., Molitor, M., Kuntic, M., Hahad, O., Röösli, M., Engelmann, N., Basner, M., Daiber, A., & Sørensen, M. (2024). Transportation noise pollution and cardiovascular health. Circulation Research, 134(9), 1113–1135. Link to source: https://doi.org/10.1161/CIRCRESAHA.123.323584

de Nazelle, A., Nieuwenhuijsen, M., Antó, J., Brauer, M., Briggs, D., Charlotte Braun-Fahrlander, C., Cavill, N., Cooper, A., Desqueyroux, H., Fruin, S., Hoek, G., Panis, L., Janssen, N., Jerrett, M., Joffe, M., Andersen, Z., van Kempen, E., Kingham, S., Kubesch, N., Leyden, K., Marshall, J., Matamala, J., Mellios, G., Mendez, M., Nassif, H., Ogilvie, D., Peiró, R., Pérez, K., Rabl, A., Ragettli, M., Rodríguez, D., Rojas, D., Ruiz, P., Sallis, J., Terwoert, J., Toussaint, J., Tuomisto, J., Zuurbier, M., & Lebret, E. (2011). Improving health through policies that promote active travel: A review of evidence to support integrated health impact assessment. Environment International, 37(4), 767-777. Link to source: https://doi.org/10.1016/j.envint.2011.02.003 

Noussan, M., Campisi, E., & Jarre, M. (2022). Carbon intensity of passenger transport modes: A review of emission factors, their variability and the main drivers. Sustainability, 14(17), Article 17. Link to source: https://doi.org/10.3390/su141710652

Prieto-Curiel, R., & Ospina, J. P. (2024). The ABC of mobility. Environment International, 185, 108541. Link to source: https://doi.org/10.1016/j.envint.2024.108541

Pro Cycling Coaching. (2025). Bike Time Calculator: How Long Does It Take to Bike Any Distance. Link to source: https://www.procyclingcoaching.com/resources/bike-time-calculator 

Rodriguez Mendez, Q., Fuss, S., Lück, S., & Creutzig, F. (2024). Assessing global urban CO2 removal. Nature Cities, 1(6), 413–423. Link to source: https://doi.org/10.1038/s44284-024-00069-x

Roser, M. (2024). Data review: How many people die from air pollution? Our World in Data. Link to source: https://ourworldindata.org/data-review-air-pollution-deaths

Seum, S., Schulz, A., & Phleps, P. (2020). The future of driving in the BRICS countries (study update 2019). Institute for Mobility Research. Link to source: https://elib.dlr.de/135710/1/2019_ifmo_BRICS_reloaded_en1.pdf

Shindell, D. T., Lee, Y., & Faluvegi, G. (2016). Climate and health impacts of US emissions reductions consistent with 2 °C. Nature Climate Change, 6(5), 503–507. Link to source: https://doi.org/10.1038/nclimate2935

Staatsen, B., Nijland, H., Kempen, E., van Hollander, A., de Franssen, A., & Kamp, I. (2004). Assessment of health impacts and policy options in relation to transport-related noise exposures (815120002).

State of Colorado. (2016). Economic and health benefits of cycling and walking. Colorado Office of Economic Development and International Trade.. ttps://choosecolorado.com/wp-content/uploads/2016/06/Economic-and-Health-Benefits-of-Bicycling-and-Walking-in-Colorado-4.pdf

Statistics Netherlands. (2024). Mobility; per person, personal characteristics, modes of travel and regions [webpage]. Statistics Netherlands. Link to source: https://www.cbs.nl/en-gb/figures/detail/84709ENG

TNMT. (2021). The environmental impact of today’s transport types. TNMT. Link to source: https://tnmt.com/infographics/carbon-emissions-by-transport-type/

Van Acker, V., & Witlox, F. (2010). Car ownership as a mediating variable in car travel behaviour research using a structural equation modelling approach to identify its dual relationship. Journal of Transport Geography, 18(1), 65–74. Link to source: https://doi.org/10.1016/j.jtrangeo.2009.05.006

Verma, S., Dwivedi, G., & Verma, P. (2022). Life cycle assessment of electric vehicles in comparison to combustion engine vehicles: A review. Materials Today: Proceedings, 49, 217–222. Link to source: https://doi.org/10.1016/j.matpr.2021.01.666

Volker, J. M. B., & Handy, S. (2021). Economic impacts on local businesses of investments in bicycle and pedestrian infrastructure: A review of the evidence. Transport Reviews, 41(4), 401–431. Link to source: https://doi.org/10.1080/01441647.2021.1912849

WHO. (2023). Despite notable progress, road safety remains urgent global issue. Link to source: https://www.who.int/news/item/13-12-2023-despite-notable-progress-road-safety-remains-urgent-global-issue

Xia, T., Zhang, Y., Crabb, S., & Shah, P. (2013). Cobenefits of replacing car trips with alternative transportation: A review of evidence and methodological issues. Journal of Environmental and Public Health, 2013(1), 797312. Link to source: https://doi.org/10.1155/2013/797312

Credits

Lead Fellow

  • Cameron Roberts, Ph.D.

Contributors

  • James Gerber, Ph.D.

  • Yusuf Jameel , Ph.D.

  • Daniel Jasper

  • Heather Jones, Ph.D.

  • Heather McDiarmid, Ph.D.

  • Alex Sweeney

Internal Reviewers

  • Aiyana Bodi

  • Hannah Henkin

  • Yusuf Jameel, Ph.D. 

  • Heather McDiarmid, Ph.D.

  • Ted Otte

  • Amanda D. Smith, Ph.D.
Effectiveness

Nonmotorized transportation can save 115.6 t CO₂‑eq /million pkm, compared with fossil fuel–powered cars (Table 1). This makes it a highly effective climate solution. Every trip shifted from a fossil fuel–powered car to cycling or pedestrian travel avoids most, if not all, of the GHG emissions associated with car travel. Nonmotorized transportation effectiveness is calculated by taking the share of each mode and multiplying it by its effectiveness, and adding this value from all three modes. 

Cars produce 116 t CO₂‑eq /million pkm (International Transport Forum, 2020; IPCC, 2023; Montoya-Torres et al., 2023; TNMT, 2021; Verma et al., 2022). Note that this value does not correspond directly to the estimates arrived at in most of these references because it is common practice to include embodied and upstream emissions in life-cycle calculations. Because we do not include embodied and upstream emissions (which are accounted for in other solutions), our estimate for the current emissions from the global vehicle fleet comes from an original calculation using values from these sources and arrives at a lower figure than they do.

Pedestrian travel and private bicycles have negligible direct emissions (Bonilla-Alicea et al., 2020; Brand et al., 2021; International Transport Forum, 2020; Noussan et al., 2022; TNMT, 2021). This means people avoid all direct GHG emissions from driving fossil fuel–powered cars when they use nonmotorized transportation instead. Thus, shifting from cars to nonmotorized transportation saves 116 t CO₂‑eq /million pkm, not including indirect emissions, such as those from manufacturing the equipment and infrastructure necessary for those forms of mobility. Life-cycle emissions from cycling are approximately 12 t CO₂‑eq /million pkm, most of which come from manufacturing bicycles (Bonilla-Alicea et al., 2019; Brand et al., 2021; ITF, 2020; Montoya-Torres et al., 2023; Noussan et al., 2020; TNMT, 2021), while emissions from pedestrian travel are negligible (TNMT, 2021). These life-cycle emissions are not quantified for this analysis, but may be addressed by other solutions in the industrial sector.

Shared bicycles provide fewer emissions savings than privately owned bicycles do. Shared bicycle schemes have direct GHG emissions of 7.49 t CO₂‑eq /million pkm, about 109 fewer than the average fossil fuel-powered car. Because people sometimes use shared bicycles for one-way trips, the bike-sharing system can become unbalanced, with fewer bicycles in places where people start their journeys and more bicycles in places where people end them. This is fixed by driving the shared bicycles from places with surplus to places with shortage, which increases emissions. The total increase in emissions caused by this can be mitigated through measures such as using electric vehicles to reposition the bikes or incentivizing riders to reposition the bicycles themselves without the use of a vehicle. 

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Table 1. Effectiveness at reducing emissions.

Unit: t CO₂‑eq /million pkm, 100-yr basis

Nonmotorized transportation
25th percentile 99.33
Mean 118.8
Median (50th percentile) 115.6
75th percentile 136.9
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Cost

Driving a fossil fuel–powered car has private costs (i.e., those that accrue to the motorist themselves) of US$0.25/pkm and public costs (for roads, lights, traffic enforcement, etc.) of US$0.11/pkm. It generates public revenues of US$0.03/pkm from taxes, fees, fines, etc. (AAA, 2024; Burnham et al., 2021; Gössling et al., 2019). This means that its net cost to the passenger is US$0.32/pkm. Cars also have externality costs, such as the cost of health care due to road injuries or air pollution (Litman, 2024). We do not factor these externalities into our cost analysis.

Nonmotorized transportation (costs weighted by mode share) has private costs of US$0.08/pkm and public costs US$0.04/pkm. It produces no revenues to the user. It has a net cost of US$0.12/pkm and saves US$0.21/pkm compared with car travel. This equals a savings of US$1,771/t CO₂‑eq (Table 2).

Pedestrian travel has private costs of US$0.09/pkm (mostly for shoes) and public costs of US$0.1/pkm (for sidewalks, staircases, bridges, etc.). It produces no new revenues. It has a net cost of US$0.10/pkm and saves US$0.23/pkm compared to car travel (Gössling et al., 2019; Litman, 2024). 

Private bicycles have private costs of US$0.06/pkm (for the cost of the bicycle itself, as well as repairs, clothing, etc.) and public costs of US$0.002/pkm (for bike lanes and other infrastructure). They produce no new revenues. They have net costs of US$0.07/pkm and save US$0.26/pkm compared to car travel (Gössling et al., 2019; Litman, 2024). These costs are cheaper than those of pedestrian travel on a per-pkm basis because, while a bicycle costs more than a pair of shoes, it can also travel much farther.

Shared bicycle systems have different cost structures. They can be very expensive (US$9.00/km in London), free (Buenos Aires) and very inexpensive (less than US$0.00 in Tehran) based on what operators charge users. Rides are usually priced by time rather than distance (DeMaio, 2009). Calculations were made as to distance covered by time to arrive at a price per km (CityTransit Data, 2025; Fishman & Schepers, 2016; Pro Cycling Coaching, 2025). Assuming that this roughly covered operating costs, it means that these systems cost US$0.22/pkm more than car travel.

An important consideration for each of these is that we must divide the cost of a bicycle, car, pair of shoes, or piece of infrastructure (road, bike lane, sidewalk) by the pkm of travel it supports over its lifespan. This means that nonmotorized transportation, which is cheaper but slower than cars, can have less of a cost advantage per pkm than might seem intuitive, and is part of the reason why cycling is cheaper per pkm than pedestrian travel. In addition, all of these estimates are based on very limited data and research and should be treated as approximate. Lastly, per-pkm infrastructural costs of cycling and pedestrian travel will decrease as cyclists and pedestrians use the infrastructure more intensively.

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Table 2. Cost per unit of climate impact.

Unit: 2023 US$/t CO₂‑eq , 100-yr basis

Nonmotorized transportation
Median -1,771
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Learning Curve

Walking and cycling are mature technologies, so the concept of a learning rate is not applicable.

There is also limited opportunity for cost reductions in cycling or pedestrian infrastructure built using construction techniques very similar to those used in the road industry. However, while learning effects might not do much to reduce the costs of nonmotorized transportation infrastructure, they could do a great deal to improve its effectiveness. Safe cycling infrastructure, in particular, has improved considerably over the past few decades. This could continue into the future as best practices are further improved.

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Speed of Action

Speed of action refers to how quickly a climate solution physically affects the atmosphere after it is deployed. This is different from speed of deployment, which is the pace at which solutions are adopted.

At Project Drawdown, we define the speed of action for each climate solution as emergency brake, gradual, or delayed.

Improve Nonmotorized Transportation is a GRADUAL climate solution. It has a steady, linear impact on the atmosphere. The cumulative effect over time builds as a straight line.

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Caveats

Increases to the modal share of nonmotorized transportation only have the benefits discussed here if they replace travel by car. Replacing public transit travel with travel using nonmotorized transportation will have a much smaller climate benefit. The climate benefit of nonmotorized mobility will also diminish if the average emissions of the global car fleet shrink, for example, due to the wider adoption of electric vehicles. 

There are also uncertainties around trip length. A small number of long trips taken by car will not be replaceable by nonmotorized transportation. Replacing the average trip by car with cycling or pedestrian travel will, in many cases, require that trip to be shortened (for example, by placing businesses closer to people’s homes). If this is not possible, increased adoption of nonmotorized transportation will apply to only some trips, reducing the impact on both emissions and costs.

Weather and climate pose significant challenges and risks for nonmotorized transportation. Extreme heat or cold, wind, rain, or storms can make people reluctant to travel without the protection of a vehicle and, in some cases, can make doing so unsafe (Gössling et al., 2023). This will reduce the adoption of nonmotorized transportation in some places, although it can be mitigated through measures such as providing information and subsidies for proper clothing, removing or grooming snow on bicycle paths, and providing indoor/covered paths that allow pedestrians to travel through a city without exposure to the elements.

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Current Adoption

Analysts most frequently report adoption of nonmotorized transportation as a percentage modal share of all trips taken in a city. Cities around the world have radically different modal shares of bicycle and pedestrian trips. Cities in LMICs often have a high nonmotorized modal share because many people cannot afford cars. Cities in high-income countries are often difficult to navigate without a car, resulting in low modal shares for nonmotorized transportation (Prieto-Curiel & Ospina, 2024). 

Prieto-Curiel and Ospina (2024) estimated that northern North America (the United States and Canada) had the lowest modal share of nonmotorized transportation, at 3.5%. Western Europe reached 29% modal share, while Western and Eastern Africa reached 42.9% and 46%, respectively.

Converting these numbers into vehicle-kilometers traveled on a national level for various countries requires assumptions. A population-weighted average of data available from the United States and several Western European countries finds that people take approximately three 13.2 km trips per day, totaling 39.7 km of daily travel with considerable variation between countries (Christensen & Vázquez, 2013; Department for Transport, 2024; Federal Highway Administration, 2022; Statistics Netherlands, 2024). For example, English people in 2022 traveled an average of 25.5 km/day, while Americans in 2020 traveled 53.5 km/day. The value we use in our analysis comes from a population-weighted average that excludes data from 2020 and 2021 to exclude data skewed by the COVID-19 pandemic. Because the United States has by far the highest population of the countries for which we found data, it skews the average much higher than many of the European countries. World data (ITF, 2021) reports that nonmotorized transportation is 14.4% of all urban pkm.

We assumed that in urban environments, each trip taken by nonmotorized transportation corresponds to one fewer car trip of this average length. This implies that nonmotorized transportation currently shifts approximately 5.6 trillion pkm from cars (Table 3). However, it should be noted that this figure includes low-income countries, where some residents have less access to private vehicles.

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Table 3. Current (2024) adoption level.

Unit: million pkm/yr*

25th percentile 826,600
Mean 5,556,000
Median (50th percentile) 3,723,000
75th percentile 9,652,000

*These data are extrapolated from a range of individual city estimates from 2010 to 2020 (Prieto-Curiel and Ospina, 2024) and world data (ITF, 2021).

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Adoption Trend

In all cities for which appropriate data exist, nonmotorized transportation showed a growth rate of 0.45% of all passenger trips per year (Prieto-Curiel & Ospina, 2024). This amounts to 49 billion pkm (Table 4) according to our estimation procedure outlined above. In some cities, adoption has grown much more quickly. For example, Hanover, Germany, achieved an average growth of 7.8%/yr in 2011–2017, which amounts to approximately 593 million additional pkm traveled by bicycle every year during that time. However, the rate of adoption is extremely variable. The 25th percentile of estimates shows a global decline in nonmotorized transportation to the tune of 135 billion fewer pkm shifted to nonmotorized modes every year.

Adoption rates of nonmotorized transportation vary widely within a country and between different years within the same city (Prieto-Curiel & Ospina, 2024).

Many people, particularly in LMICs, walk or cycle because they have limited access to a vehicle. When countries become wealthier, travel often shifts from nonmotorized transportation to cars (Seum et al., 2020). If transportation policy in these countries prioritizes car-free mobility, high levels of nonmotorized transportation adoption could potentially be preserved even as living standards increase.

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Table 4. 2023–2024 adoption trend.

Unit: million pkm/yr

25th percentile -134,700
Mean 29,570
Median (50th percentile) 49,400
75th percentile 296,900
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Adoption Ceiling

We estimated that 20.2% of all trips in cities worldwide, or approximately 5.6 trillion pkm/yr, are traveled by nonmotorized transportation, while 66.2%, or approximately 18.2 trillion pkm/yr, are traveled by fossil fuel–powered car. This suggests that switching all urban trips currently taken by car to nonmotorized transportation would lead to a nonmotorized modal share of 86.4% in cities globally, or 19.7 trillion pkm/yr (Table 5).

This calculation uses the same assumptions discussed under Current Adoption above. In this case, however, our assumption that every nonmotorized trip is shifted from a car trip of the same length requires further justification. We are not assuming that very long car trips, trips on highways, etc., are replaced directly by bicycle or pedestrian trips. Instead, we assume that shorter nonmotorized trips can substitute for longer car trips with appropriate investment in better urban planning and infrastructure. So, for example, a 10 km drive to a large grocery store could be replaced by a 1 km walk to a neighborhood grocery store. 

This would require replanning many cities so they better accommodate shorter trips. It would also require improving options for people with disabilities or those carrying heavy loads. And it would face climatic and topographic constraints. Furthermore, it is unlikely that all car traffic would ever be substituted by any single alternative mode. Other sustainable modes, particularly public transit, are likely to play a role.

It is also possible for rural trips to be undertaken by nonmotorized transportation. Indeed, this is already very common in low-and middle-income countries. However, rural data are sparse, and discerning how many trips could be shifted to nonmotorized travel in these areas is highly speculative. Therefore, we omit rural areas from our analysis.

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Table 5. Adoption ceiling.

Unit: million pkm/yr

Median (50th percentile) 19,690,000
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Achievable Adoption

To estimate the upper bound of feasible adoption, we assumed that urban trips taken by fossil fuel–powered cars can be shifted to nonmotorized transportation until the latter accounts for 65% of trips (the current highest modal share of nonmotorized transportation in any city with a population of more than one million) or until car travel decreases to 7% of trips (the current lowest modal share of fossil fuel–powered cars in any city with a population of more than one million). This corresponds to a total achievable nonmotorized transportation modal share of 16.3 trillion pkm/yr (Table 6).

To set the lower bound, we do the same calculation as above, but for each individual region, adding up all the resultant modal shifts to get a global figure. So, for example, every East Asian city might reach the nonmotorized transportation modal share of Singapore (23% of trips), while every northern European city might reach that of Copenhagen, Denmark (41% of trips). This corresponds to a total achievable nonmotorized transportation modal share of 12.4 trillion pkm/yr.

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Table 6. Range of achievable adoption levels.

Unit: million pkm/yr

Current adoption 5,556,000
Achievable – low 12,369,000
Achievable – high 16,340,000
Potential adoption 19,690,000
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If all cycling and pedestrian trips undertaken today would otherwise have happened by car, they are currently displacing approximately 0.6 Gt CO₂‑eq/yr emissions (Table 7). This is an overestimate, however, since this figure includes data from places where most people have low access to cars.

Walking and private bicycles have a different effectiveness than shared bicycles. To calculate the climate impacts of different levels of adoption, we applied the effectiveness in the share of each mode of nonmotorized transportation. Walking and private bicycling are 94.4% of nonmotorized pkm and shared bicycling is 5.3%. This gives nonmotorized transportation effectiveness at reducing emissions 115.6 t CO₂‑eq /million pkm.

On the lower end, if every city achieved a pedestrian and cycling modal share equivalent to the least-motorized city in its region, it would save 1.4 Gt CO₂‑eq/yr. On the higher end, if every city shifted enough passenger car traffic to achieve a car modal share as low as Hong Kong, China, it would save 1.9 Gt CO₂‑eq/yr. If all trips taken by car were shifted onto nonmotorized transportation (an unrealistic scenario), it would save 2.3 Gt CO₂‑eq/yr.

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Table 7. Climate impact at different levels of adoption.

Unit: Gt CO₂‑eq/yr, 100-yr basis

Current adoption 0.642
Achievable – low 1.430
Achievable – high 1.889
Adoption ceiling 2.276
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Additional Benefits

Health and Air Quality

Air pollution kills approximately 7 million people yearly (Roser, 2024). By reducing vehicle emissions, nonmotorized transportation can alleviate related air pollution (Mailloux et al., 2021) and thereby reduce premature deaths. For example, cutting U.S. transportation emissions by 75% by 2030 could prevent 14,000 premature deaths annually due to decreased exposure to PM2.5 and ozone (Shindell et al., 2016). 

Nonmotorized transportation has other health and safety benefits (Blondiau et al., 2016; European Commission, 2019; Glazener & Khreis, 2019; Gössling et al., 2023; Mueller et al., 2015; State of Colorado, 2016; Xia et al., 2013). Switching from driving to walking or cycling boosts health by promoting physical activity and decreasing risks of cardiovascular issues, diabetes, and mental disorders (Mailloux et al., 2021).

Noise pollution from motorized vehicles has significant impacts on cardiovascular health, mental health, and sleep disturbances, contributing to 1.6 million lost healthy life years in 2004 and up to 1,100 deaths attributable to hypertension in Europe in 2024 (Staatsen et al., 2004; Munzel et al., 2024). Enhancing nonmotorized transportation can reduce the health impacts of traffic noise (de Nazelle et al., 2011).

Finally, nonmotorized transportation improves quality of life. It increases opportunities for human connection, integrates physical activity and fun into daily commutes, and increases the autonomy of less mobile groups such as children and elders. Cities with high modal shares for nonmotorized transportation generally have high quality of life (Adamos et al., 2020; Günther & Krems, 2022; Glazener and Khreis, 2019).

The use of nonmotorized transportation can reduce car crashes, which kill around 1.2 million people annually (WHO, 2023).

Income and Work

Nonmotorized transportation infrastructure tends to be good for local businesses. Cyclists and pedestrians are more likely to stop at businesses they pass and therefore spend more money locally, creating more jobs (Volker & Handy, 2021). 

Nature Protection

In 2011, roads and associated infrastructure accounted for 10–30% of land in residential areas and 50–70% of land in commercial areas (Litman, 2011). Transforming these lands into green spaces could provide additional habitats and reduce biodiversity loss while increasing the protection of land, soil, and water resources (European Commission, 2019).

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Risks

Some literature suggested that nonmotorized transportation can lead to gentrification because bike lanes and pleasant walkable streets can increase property values, driving people who used to live in a neighborhood into other places that might still be car-dependent (Flanagan et al., 2016). This risk can be addressed by ensuring that nonmotorized transportation infrastructure is built in an equitable way, connecting different neighborhoods regardless of their social and economic status. Increasing the number of neighborhoods accessible without a car will mean that people do not have to pay a premium to live in those neighborhoods. This will avoid making accessibility without a car a privilege that only the wealthy can afford.

Cycling in a city with lots of traffic and poor cycling infrastructure puts cyclists at risk of injury from collisions with cars. This risk, however, comes mainly from the presence of cars on roads. Reducing the number of cars on the road by shifting trips to other modes can improve safety for cyclists and pedestrians (Bopp et al., 2018).

The positive impacts that nonmotorized transportation have on traffic congestion could be self-defeating if not managed well. This is because less congestion will make driving more appealing, which can, in turn, lead to additional induced demand, increasing car use and congestion (Hymel et al., 2010).

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Interactions with Other Solutions

Reinforcing

Nonmotorized transportation can help passengers access public transit systems, train stations, and carpool pickup points. This is important because research suggests that the key to a low-carbon mobility system is to reduce the need for people to own cars (Van Acker & Witlox, 2010).

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Electric bicycles use the same infrastructure as nonmotorized transportation – especially conventional bicycles. Building bike lanes, bike paths, mixed-use paths, and similar infrastructure for cyclists and pedestrians can also help with the uptake of electric bicycles. This is even more true for shared electric bicycles, which can and often do use the same sharing systems as shared conventional bicycles.

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One way to encourage the adoption of electric cars is through electric car–sharing services, in which people can access a communal electric car when they need it. This has the additional benefit of reducing the need for car ownership, which is closely correlated with car use (Van Acker and Witlox, 2010). Good nonmotorized transportation infrastructure can make it easier for users of these services to access shared vehicles parked at central locations.

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Competing

Electric cars, hybrid cars, electric scooters and motorcycles, and nonmotorized transportation compete for the same pool of total pkm. Increased use of nonmotorized transportation could reduce kilometers traveled using electric and hybrid cars and electric scooters and motorcycles.

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Consensus

Consensus of effectiveness in decarbonizing the transportation sector: High

The large reductions in emissions that come from shifting passenger transportation from fossil fuel-powered cars to nonmotorized modes are not controversial. There is some disagreement, however, over how many pkm traveled by car can be realistically shifted to nonmotorized transportation.

Brand et al. (2021) compared the GHG emissions of active transportation with those of cars. They concluded that “locking in, investing in and promoting active travel should be a cornerstone of sustainability strategies, policies and planning.”

The Intergovernmental Panel on Climate Change (IPCC, 2023) sixth assessment report mentioned nonmotorized transportation as a solution in its transportation chapter. The authors expressed high confidence in the potential of these transportation modes to reduce emissions and recommended policy and infrastructural measures to support them.

Litman’s (2024) study of the costs and benefits of active transportation summarized the direct financial costs as well as externalities associated with pedestrian and bicycle travel compared with travel by fossil fuel–powered car. Litman noted that “active transport can provide relatively large energy savings if it substitutes for short urban trips that have high emission rates per mile due to cold starts (engines are inefficient during the first few minutes of operation) and congestion. As a result, each 1% shift from automobile to active travel typically reduces fuel consumption 2–4%.”

This research is, unfortunately, heavily biased toward richer countries, especially in Europe and North America, even though nonmotorized transportation plays a very important role in low- and middle-income countries (LMICs). The research on this topic is also biased toward cities, even though nonmotorized transportation can be a valuable means of mobility in rural areas. 

The results presented in this document summarize findings from 19 reviews and meta-analyses and 14 original studies reflecting current evidence from 84 countries, primarily the United States, the United Kingdom, and the European Union. We recognize this limited geographic scope creates bias, and hope this work inspires research and data sharing on this topic in underrepresented regions.

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Dashboard

Solution Basics

million passenger kilometers (million pkm)

t CO₂-eq (100-yr)/unit
099.33115.6
units/yr
Current 5.556×10⁶ 01.236×10⁷1.634×10⁷
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 0.642 1.431.889
US$ per t CO₂-eq
-1,771
Gradual

CO₂, CH₄, N₂O, BC

Trade-offs

Production of equipment (such as bicycles) and infrastructure (such as sidewalks) creates some emissions, but these are small when divided by the total distance traveled by pedestrians and cyclists. On a per-pkm basis, this makes little difference in the emissions saved by nonmotorized transportation. 

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% population
0–20
20–40
40–60
60–80
> 80

Percentage of city population living near protected bikeways, 2023

Proximity to related infrastructure, such as protected bikeways, facilitates the safe and convenient use of nonmotorized modes of transportation.

Reich, D. T. & Braga, K. (2024). Atlas of Sustainable City Transport [Data set]. Institute for Transportation and Development Policy. Retrieved June 2, 2025 from atlas.itdp.org

% population
0–20
20–40
40–60
60–80
> 80

Percentage of city population living near protected bikeways, 2023

Proximity to related infrastructure, such as protected bikeways, facilitates the safe and convenient use of nonmotorized modes of transportation.

Reich, D. T. & Braga, K. (2024). Atlas of Sustainable City Transport [Data set]. Institute for Transportation and Development Policy. Retrieved June 2, 2025 from atlas.itdp.org

Maps Introduction

Nonmotorized transportation effectiveness is high across all geographic regions, though the built environment, safety, and socio-cultural norms heavily shape its adoption and impact. Key determinants of effectiveness include the extent of safe and connected infrastructure (e.g., sidewalks, bike lanes, protected intersections), land-use patterns supporting short trips, and public policies prioritizing nonmotorized transportation.

Overall, effectiveness depends on adoption. In many cities across Europe and Asia, walking and cycling remain integral to daily travel. Cities like Amsterdam, Copenhagen, and Tokyo have successfully integrated nonmotorized modes into their broader transport systems through dedicated infrastructure and supportive urban design. In contrast, cities in North America, Sub-Saharan Africa, and parts of Latin America often lack safe, accessible infrastructure, which limits adoption.

Socioeconomic factors, including income levels, urban design, and perceptions of status, also influence the adoption of nonmotorized transport. In wealthier regions, cycling may be viewed as a lifestyle choice or an environmental statement, whereas in lower-income settings, it may be perceived as a necessity or even a sign of economic disadvantage, influencing user behavior and policy support (Seum et al., 2020).

Although shared bicycles have a lower effectiveness than walking or private bicycles, they are much more effective than cars. Increasing the number of shared bicycle systems in any geographic area can increase adoption and, therefore, make them more effective. This is particularly effective in lower-income areas where owning a private bicycle might be cost-prohibitive (Litman, 2024). Increasing shared systems in less urban and more suburban areas can be more effective, as they often replace trips made by car (Brand et al., 2021).

Nonmotorized modes are generally resilient and functional in a wide range of climates. Extreme weather conditions, including high heat, heavy rainfall, or snow, can reduce walking and cycling, although these can be mitigated through appropriate infrastructure (e.g., shaded or covered walkways, snow clearing, bike shelters).

Action Word
Improve
Solution Title
Nonmotorized Transportation
Classification
Highly Recommended
Lawmakers and Policymakers
  • Use nonmotorized transportation.
  • Reduce the associated time, distance, risk, and risk perception of nonmotorized transportation.
  • Improve infrastructure such as sidewalks, footpaths, and bike lanes.
  • Implement traffic-calming methods such as speed bumps.
  • Increase residential and commercial density.
  • Use a citizen-centered approach when designing infrastructure.
  • Enact infrastructure standards for nonmotorized transportation, such as curb ramp designs, and train contractors to implement them.
  • Establish public bike-sharing programs.
  • Create dedicated coordinating bodies across government agencies, businesses, and the public to develop nonmotorized infrastructure.
  • Disincentivize car ownership through reduced access, increases in parking fares, taxes, or other means. 

Further information:

Practitioners
  • Use nonmotorized transportation.
  • Share your experiences, tips, and reasons for choosing your modes of transportation.
  • Participate in local bike groups, public events, and volunteer opportunities.
  • Advocate to local officials for infrastructure improvements and note specific locations for improvements.
  • Encourage local businesses to create employee incentives.
  • Create “bike buses” or “walking buses” for the community and local schools.

Further information:

Business Leaders
  • Use nonmotorized transportation.
  • Ensure your business is accessible via nonmotorized transportation.
  • Advocate for better infrastructure for nonmotorized transportation.
  • Educate customers about the local infrastructure.
  • Partner with other businesses to encourage employees to cycle or walk.
  • Encourage employees to walk or cycle to and from work as their circumstances allow.
  • Create educational materials for employees on commuting best practices.
  • Offer employees pre-tax commuter benefits to include reimbursement for nonmotorized travel expenses.
  • Organize staff bike rides to increase familiarity and comfort with bicycling.
  • Install adequate bike storage, such as locking posts.
  • Emphasize walking and biking as part of company-wide sustainability initiatives and communicate how walking and biking support broader GHG emission reduction efforts.

Further information:

Nonprofit Leaders
  • Use nonmotorized transportation.
  • Ensure your office is accessible to nonmotorized transportation.
  • Advocate for infrastructure improvements and note specific locations where improvements can be made.
  • Encourage local businesses to create employee incentives.
  • Create “bike buses” or “walking buses” for the community and/or local schools.
  • Offer free classes on subjects such as bike maintenance, local bike routes, or what to know before purchasing a bike.
  • Host or support community participation in local infrastructure design.
  • Join public-private partnerships to encourage biking and walking, emphasizing the health and savings benefits.

Further information:

Investors
  • Use nonmotorized transportation.
  • Deploy capital to efforts that improve bicycle and walking comfort, convenience, access, and safety.
  • Invest in public or private bike-sharing systems.
  • Invest in local supply chains for bicycles and other forms of nonmotorized transportation.
  • Seek investment opportunities that reduce material and maintenance costs for bicycles.
  • Finance bicycle purchases via low-interest loans.
  • Consider investments in nonmotorized transportation start-ups.

Further information:

Philanthropists and International Aid Agencies
  • Use nonmotorized transportation.
  • Award grants to local organizations advocating for improved walking and bicycle infrastructure.
  • Build capacity for walking and bicycle infrastructure design and construction.
  • Support organizations that distribute, refurbish, and/or donate bikes in your community.
  • Facilitate access to bicycle maintenance and supplies.
  • Host or support community education or participation efforts.
  • Donate fixtures such as street lights, guardrails, and road signs.
  • Educate the public and policymakers on the benefits and best practices of nonmotorized transportation.

Further information:

Thought Leaders
  • Use nonmotorized transportation.
  • Focus messages on key decision factors for nonmotorized commuters, such as the associated health benefits and importance of fitness, climate and environmental benefits, weather forecasts, and traffic information.
  • Highlight principles of safe urban design and point out dangerous areas.
  • Share information on local bike and walking routes, general bike maintenance tips, items to consider when purchasing a bike, and related educational information.
  • Collaborate with schools on bicycle instruction, including safe riding habits and maintenance.

Further information:

Technologists and Researchers
  • Use nonmotorized transportation.
  • Examine and improve elements of infrastructure design.
  • Improve circularity, repairability, and ease of disassembly for bikes.
  • Increase the physical carrying capacities (storage) for walkers and bicyclists to facilitate shopping and transporting children, pets, and materials.
  • Identify and encourage the deployment of messaging that enhances nonmotorized transportation use.

Further information:

Communities, Households, and Individuals
  • Use nonmotorized transportation.
  • Share your experiences, tips, and reasons for choosing nonmotorized transportation.
  • Participate in local bike groups, public events, and volunteer opportunities.
  • Advocate to local officials for infrastructure improvements and note specific locations where improvements can be made.
  • Encourage local businesses to create employee incentives for using nonmotorized transportation.
  • Create “bike buses” or “walking buses” for the community and local schools.

Further information:

Sources
Evidence Base

Consensus of effectiveness in decarbonizing the transport sector: High

The large reductions in emissions that come from shifting passenger transportation from fossil fuel-powered cars to nonmotorized modes are not controversial. There is some disagreement, however, over how many pkm traveled by car can be realistically shifted to nonmotorized transportation.

Brand et al. (2021) compared the GHG emissions of active transportation with those of cars. They concluded that “locking in, investing in and promoting active travel should be a cornerstone of sustainability strategies, policies and planning.”

The Intergovernmental Panel on Climate Change (IPCC, 2023) sixth assessment report mentioned nonmotorized transportation as a solution in its transportation chapter. The authors expressed high confidence in the potential of these transportation modes to reduce emissions and recommended policy and infrastructural measures to support them.

Litman’s (2024) study of the costs and benefits of active transportation summarized the direct financial costs as well as externalities associated with pedestrian and bicycle travel compared with travel by fossil fuel–powered car. Litman noted that “active transport can provide relatively large energy savings if it substitutes for short urban trips that have high emission rates per mile due to cold starts (engines are inefficient during the first few minutes of operation) and congestion. As a result, each 1% shift from automobile to active travel typically reduces fuel consumption 2–4%.”

This research is, unfortunately, heavily biased toward richer countries, especially in Europe and North America, even though nonmotorized transportation plays a very important role in low- and middle-income countries (LMICs). The research on this topic is also biased toward cities, even though nonmotorized transportation can be a valuable means of mobility in rural areas. 

The results presented in this document summarize findings from 19 reviews and meta-analyses and 14 original studies reflecting current evidence from 84 countries, primarily the United States, the United Kingdom, and the European Union. We recognize this limited geographic scope creates bias, and hope this work inspires research and data sharing on this topic in underrepresented regions.

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Updated Date

Mobilize Hybrid Cars

Submitted by Drawdown Admin on
Sector
Transportation
Mode
Cut Emissions
Cluster
Enhance Efficiency
Image
Start button on a hybrid vehicle
Coming Soon
Off
Summary

The Mobilize Hybrid Cars solution entails shifting trips from fossil fuel–powered internal combustion engine (ICE) cars to more efficient, lower emitting hybrid cars. Hybrid cars include hybrid electric cars (HEVs) and plug-in hybrid electric cars (PHEVs). They are four-wheeled passenger cars that combine an ICE with an electric motor and battery to improve fuel efficiency and reduce emissions. This definition includes hybrid sedans, sport utility vehicles (SUVs), and pickup trucks, but excludes fully electric cars, two-wheeled vehicles, and hybrid commercial or freight vehicles, such as hybrid buses and delivery trucks. Hybrid cars are a transitional climate solution because they are more efficient and produce fewer emissions per distance traveled than do fossil fuel–powered ICE cars but still rely on fossil fuel combustion.

Income & work,Health
Air quality
Description for Social and Search
Mobilize Hybrid Cars is a Highly Recommended climate solution. By combining internal combustion engines with electric motors, hybrids reduce fuel use and air pollution.
Overview

Hybrid cars reduce fuel consumption and tailpipe emissions by relying on electric propulsion for part of their operation. There are currently more than 45 million hybrids making up 2.2% of the more than two billion global car stock. HEVs provide the same functionality as fossil fuel–powered ICE cars, but combine an ICE with an electric motor and battery to improve fuel efficiency. Unlike electric cars, HEVs do not require external charging; instead, they recharge their battery using regenerative braking and energy from the engine. This allows them to use electric power at low speeds and in stop-and-go traffic, reducing fuel consumption and emissions compared to traditional gasoline or diesel cars. PHEVs work similarly but have larger batteries that can be charged using the electricity grid. This enables them to operate in full-electric mode for a limited distance before switching to hybrid mode when the battery is depleted.

Hybrid cars typically offer better acceleration than their purely fossil fuel–powered ICE counterparts, especially at lower speeds. This is because electric motors deliver instant torque, allowing hybrids to respond quickly when accelerating from a stop. PHEVs tend to have stronger electric motors and thus better acceleration. The high torque at low speeds eliminates the need for inefficient gear changes and allows near-constant operation at optimal conditions because the ICE is usually engaged at efficient conditions. This improves the real-world fuel economy 39–58% compared to fossil fuel–powered ICE cars of similar size (Zhang et al., 2025).

While hybrid cars reduce fuel consumption and tailpipe emissions by relying on electric propulsion for part of their operation, their overall emissions depend on how much they use the ICE versus the electric motor, and, for PHEVs, on the emissions intensity of the electricity source used for charging. PHEVs can offer greater potential for emission reductions if charged from low-carbon electricity sources. If driven primarily in electric mode, PHEVs can significantly reduce GHG emissions compared to fossil fuel–powered ICE cars, but if the battery is not regularly charged, their fuel consumption may be similar to or even higher than standard HEVs (Dornoff, 2021; Plötz et al., 2020).

Hybrid technologies also improve car efficiency by reducing energy losses. First, both HEVs and PHEVs recover energy through regenerative braking, converting kinetic energy into electricity and storing it in the battery (Yang et al., 2024). Second, their electric powertrains are more efficient than those of traditional ICEs, particularly in urban driving conditions where frequent stops and starts are common (Verma et al., 2022). These advantages contribute to lower fuel consumption and emissions compared to fossil fuel–powered ICE cars. However, the environmental benefits of hybrids depend on driving patterns, battery charging habits, and the carbon intensity of the electricity grid used to charge PHEVs.

Hybrid cars reduce emissions of CO₂, methane, and nitrous oxide to the atmosphere by increasing fuel efficiency compared to fossil fuel–powered ICE cars, which emit these gases from their tailpipes. Because they are typically fueled by gasoline, hybrid cars produce more methane than any diesel-fueled cars they might be replacing. As a result, their 20-yr effectiveness at addressing climate change is lower than their 100-yr effectiveness. 

Agusdinata, D. B., Liu, W., Eakin, H., & Romero, H. (2018). Socio-environmental impacts of lithium mineral extraction: Towards a research agenda. Environmental Research Letters, 13(12). Article 123001. Link to source: https://doi.org/10.1088/1748-9326/aae9b1

Alberini, A., Di Cosmo, V., & Bigano, A. (2019). How are fuel efficient cars priced? Evidence from eight EU countries. Energy Policy, 134, Article 110978. Link to source: https://doi.org/10.1016/j.enpol.2019.110978

Anenberg, S., Miller, J., Henze, D., & Minjares, R. (2019). A global snapshot of the air pollution-related health impacts of transportation sector emissions in 2010 and 2015. International Council on Clean Transportation. Link to source: https://theicct.org/publication/a-global-snapshot-of-the-air-pollution-related-health-impacts-of-transportation-sector-emissions-in-2010-and-2015/

Asia-Pacific Economic Cooperation. (2024). Connecting traveler choice with climate outcomes: Innovative greenhouse gas emissions reduction policies and practices in the APEC region through traveler behavioral change. Link to source: https://www.apec.org/docs/default-source/publications/2024/9/224_tpt_connecting-traveler-choice-with-climate-outcomes.pdf 

Bell-Pasht, A. (2024). Combined energy burdens: Estimating total home and transportation energy burdens [Topic brief]. American Council for an Energy-Efficient Economy. Link to source: https://www.aceee.org/topic-brief/2024/05/combined-energy-burdens-estimating-total-home-and-transportation-energy-burdens

BEUC. (2021). Electric cars: Calculating the total cost of ownership for consumers [Technical report]. The European Consumer Organisation. Link to source: https://www.beuc.eu/reports/electric-cars-calculating-total-cost-ownership-consumers-technical-report

BloombergNEF. (2024). Electric vehicle outlook 2024. Bloomberg Finance L.P. Link to source: https://about.bnef.com/electric-vehicle-outlook/

Carey, J. (2023, January 11). The other benefit of electric vehicles [News feature]. Proceedings of the National Academy of Sciences, 120(3), Article e2220923120. Link to source: https://doi.org/10.1073/pnas.2220923120

Castelvecchi, D. (2021, August 17). Electric cars and batteries: How will the world produce enough? [News feature]. Nature, 596(7872), 336–339. Link to source: https://doi.org/10.1038/d41586-021-02222-1

Choma, E. F., Evans, J. S., Hammitt, J. K., Gómez-Ibáñez, J. A., & Spengler, J. D. (2020). Assessing the health impacts of electric vehicles through air pollution in the United States. Environment International, 144, Article 106015. Link to source: https://doi.org/10.1016/j.envint.2020.106015 

Dornoff, J. (2021). Plug-in hybrid vehicle CO2 emissions: How they are affected by ambient conditions and driver mode selection [White paper]. International Council on Clean Transportation. Link to source: https://theicct.org/publication/plug-in-hybrid-vehicle-co2-emissions-how-they-are-affected-by-ambient-conditions-and-driver-mode-selection/

Duncan, D., Ku, A. L., Julian, A., Carley, S., Siddiki, S., Zirogiannis, N., & Graham, J. D. (2019). Most consumers don’t buy hybrids: Is rational choice a sufficient explanation? Journal of Benefit-Cost Analysis, 10(1), 1–38. Link to source: https://doi.org/10.1017/bca.2018.24

Fortune Business Insights. (2025). Hybrid vehicle market size, share & growth report, 2024–2032. Link to source: https://www.fortunebusinessinsights.com/hybrid-vehicle-market-105435

Fulton, L. (2020). A publicly available simulation of battery electric, hybrid electric, and gas-powered vehicles. Energies, 13(10), Article 2569. Link to source: https://doi.org/10.3390/en13102569

Furch, J., Konečný, V., & Krobot, Z. (2022). Modelling of life cycle cost of conventional and alternative vehicles. Scientific Reports, 12(1), Article 10661. Link to source: https://doi.org/10.1038/s41598-022-14715-8

Garcia, E., Johnston, J., McConnell, R., Palinkas, L., & Eckel, S. P. (2023). California’s early transition to electric vehicles: Observed health and air quality co-benefits. Science of The Total Environment, 867, Article 161761. Link to source: https://doi.org/10.1016/j.scitotenv.2023.161761

International Energy Agency. (2021). Global fuel economy initiative 2021 data explorer [Data tool]. Link to source: https://www.iea.org/data-and-statistics/data-tools/global-fuel-economy-initiative-2021-data-explorer

International Energy Agency. (2022). Electric vehicles: Total cost of ownership tool [Data tool]. Link to source: https://www.iea.org/data-and-statistics/data-tools/electric-vehicles-total-cost-of-ownership-tool

International Energy Agency. (2023). Energy technology perspectives 2023. Link to source: https://www.iea.org/reports/energy-technology-perspectives-2023

International Energy Agency. (2024). Global EV outlook 2024. Link to source: https://www.iea.org/reports/global-ev-outlook-2024

International Transport Forum. (2020). Good to go? Assessing the environmental performance of new mobility [Corporate Partnership Board Report]. OECD/ITF Publishing. Link to source: https://www.itf-oecd.org/sites/default/files/docs/environmental-performance-new-mobility.pdf

Isenstadt, A., & Slowik, P. (2025). Hybrid vehicle technology developments and opportunities in the 2025–2035 time frame [Working paper]. International Council on Clean Transportation. Link to source: https://theicct.org/publication/hybrid-vehicle-technology-developments-and-opportunities-in-the-2025-2035-time-frame-feb25/

Jones, S. J. (2019). If electric cars are the answer, what was the question? British Medical Bulletin, 129(1), 13–23. Link to source: https://doi.org/10.1093/bmb/ldy044

Kerr, G. H., Goldberg, D. L., & Anenberg, S. C. (2021). COVID-19 pandemic reveals persistent disparities in nitrogen dioxide pollution. Proceedings of the National Academy of Sciences, 118(30), Article e2022409118. Link to source: https://doi.org/10.1073/pnas.2022409118

Kittner, N., Tsiropoulos, I., Tarvydas, D., Schmidt, O., Staffell, I., & Kammen, D. M. (2020). Electric vehicles. In M. Junginger & A. Louwen (Eds.), Technological learning in the transition to a low‑carbon energy system: Conceptual issues, empirical findings, and use in energy modeling (pp. 145–163). Academic Press. Link to source: https://doi.org/10.1016/B978-0-12-818762-3.00009-1

Larson, E., Greig, C., Jenkins, J., Mayfield, E., Pascale, A., Zhang, C., Drossman, J., Williams, R., Pacala, S., Socolow, R., Baik, E., Birdsey, R., Duke, R., Jones, R., Haley, B., Leslie, E., Paustain, K., & Swan, A. (2020). Net-zero America: Potential pathways, infrastructure, and impacts [Interim report]. Princeton University, Andlinger Center for Energy and the Environment. Link to source: https://netzeroamerica.princeton.edu/the-report

Lutsey, N., Cui, H., & Yu, R. (2021). Evaluating electric vehicle costs and benefits in China in the 2020–2035 time frame [White paper]. International Council on Clean Transportation. Link to source: https://theicct.org/publication/evaluating-electric-vehicle-costs-and-benefits-in-china-in-the-2020-2035-time-frame/

Menes, M. (2021). Two decades of hybrid electric vehicle market. Journal of Civil Engineering and Transport, 3(1), 29–37. Link to source: https://doi.org/10.24136/tren.2021.003

Milovanoff, A., Posen, I. D., & MacLean, H. L. (2020). Electrification of light-duty vehicle fleet alone will not meet mitigation targets. Nature Climate Change, 10(12), 1102–1107. Link to source: https://doi.org/10.1038/s41558-020-00921-7

Mittal, V., & Shah, R. (2024). Modeling and comparing the total cost of ownership of passenger automobiles with conventional, electric, and hybrid powertrains. SAE International Journal of Sustainable Transportation, Energy, Environment, & Policy, 5(2), 179–192. Link to source: https://doi.org/10.4271/13-05-02-0013

Mustapa, S. I., Ayodele, B. V., Mohamad Ishak, W. W., & Ayodele, F. O. (2020). Evaluation of cost competitiveness of electric vehicles in Malaysia using life cycle cost analysis approach. Sustainability, 12(13), Article 5303. Link to source: https://doi.org/10.3390/su12135303

Ouyang, D., Zhou, S., & Ou, X. (2021). The total cost of electric vehicle ownership: A consumer-oriented study of China’s post-subsidy era. Energy Policy, 149, Article 112023. Link to source: https://doi.org/10.1016/j.enpol.2020.112023

Pennington, A. F., Cornwell, C. R., Sircar, K. D., & Mirabelli, M. C. (2024). Electric vehicles and health: A scoping review. Environmental Research, 251, Article 118697. Link to source: https://doi.org/10.1016/j.envres.2024.118697

Peters, D. R., Schnell, J. L., Kinney, P. L., Naik, V., & Horton, D. E. (2020). Public health and climate benefits and trade‐offs of U.S. vehicle electrification. GeoHealth, 4(10), Article e2020GH000275. Link to source: https://doi.org/10.1029/2020GH000275

Petrauskienė, K., Galinis, A., Kliaugaitė, D., & Dvarionienė, J. (2021). Comparative environmental life cycle and cost assessment of electric, hybrid, and conventional vehicles in Lithuania. Sustainability, 13(2), Article 957. Link to source: https://doi.org/10.3390/su13020957

Plötz, P., Moll, C., Li, Y., Bieker, G., & Mock, P. (2020). Real-world usage of plug-in hybrid electric vehicles: Fuel consumption, electric driving, and CO2 emissions [White paper]. International Council on Clean Transportation. Link to source: https://theicct.org/publication/real-world-usage-of-plug-in-hybrid-electric-vehicles-fuel-consumption-electric-driving-and-co2-emissions

Requia, W. J., Mohamed, M., Higgins, C. D., Arain, A., & Ferguson, M. (2018). How clean are electric vehicles? Evidence-based review of the effects of electric mobility on air pollutants, greenhouse gas emissions and human health. Atmospheric Environment, 185, 64–77. Link to source: https://doi.org/10.1016/j.atmosenv.2018.04.040

Roberts, C. (2022). Easy street for low-carbon mobility? The political economy of mass electric car adoption. In G. Parkhurst & W. Clayton (Eds.), Electrifying mobility: Realising a sustainable future for the car (Vol. 15, pp. 13–31). Emerald Publishing Limited. Link to source: https://doi.org/10.1108/S2044-994120220000015004

Romm, J. J., & Frank, A. A. (2006, April). Hybrid vehicles gain traction. Scientific American, 294(4), 72–79. Link to source: https://doi.org/10.1038/scientificamerican0406-72

Sovacool, B. K. (2019). The precarious political economy of cobalt: Balancing prosperity, poverty, and brutality in artisanal and industrial mining in the Democratic Republic of the Congo. The Extractive Industries and Society, 6(3), 915–939. Link to source: https://doi.org/10.1016/j.exis.2019.05.018

Suttakul, P., Wongsapai, W., Fongsamootr, T., Mona, Y., & Poolsawat, K. (2022). Total cost of ownership of internal combustion engine and electric vehicles: A real-world comparison for the case of Thailand. Energy Reports, 8, 545–553. Link to source: https://doi.org/10.1016/j.egyr.2022.05.213

Vega-Perkins, J., Newell, J. P., & Keoleian, G. (2023). Mapping electric vehicle impacts: Greenhouse gas emissions, fuel costs, and energy justice in the United States. Environmental Research Letters, 18(1), Article 014027. Link to source: https://doi.org/10.1088/1748-9326/aca4e6

Verma, S., Dwivedi, G., & Verma, P. (2022). Life cycle assessment of electric vehicles in comparison to combustion engine vehicles: A review. Materials Today: Proceedings, 49, 217–222. Link to source: https://doi.org/10.1016/j.matpr.2021.01.666

Weiss, M., Zerfass, A., & Helmers, E. (2019). Fully electric and plug-in hybrid cars - An analysis of learning rates, user costs, and costs for mitigating CO2 and air pollutant emissions. Journal of Cleaner Production, 212, 1478–1489. Link to source: https://doi.org/10.1016/j.jclepro.2018.12.019

World Health Organization. (2022). Number of registered vehicles [Data set]. The Global Health Observatory. Link to source: https://www.who.int/data/gho/data/indicators/indicator-details/GHO/number-of-registered-vehicles

Yang, C., Sun, T., Wang, W., Li, Y., Zhang, Y., & Zha, M. (2024). Regenerative braking system development and perspectives for electric vehicles: An overview. Renewable and Sustainable Energy Reviews, 198, Article 114389. Link to source: https://doi.org/10.1016/j.rser.2024.114389

Zhang, Y., Fan, P., Lu, H., & Song, G. (2025). Fuel consumption of hybrid electric vehicles under real-world road and temperature conditions. Transportation Research Part D: Transport and Environment, 142, Article 104691. Link to source: https://doi.org/10.1016/j.trd.2025.104691 

Credits

Lead Fellow

  • Heather Jones, Ph.D.

  • Cameron Roberts, Ph.D.

Contributors

  • Ruthie Burrows, Ph.D.

  • James Gerber, Ph.D.

  • Yusuf Jameel, Ph.D.

  • Daniel Jasper

  • Alex Sweeney

Internal Reviewers

  • Aiyana Bodi

  • Hannah Henkin

  • Zoltan Nagy, Ph.D. 

  • Ted Otte

  • Amanda D. Smith, Ph.D.

  • Christina Swanson, Ph.D.

Effectiveness

Each million pkm shifted from fossil fuel–powered cars to hybrid cars saves 27.11 t CO₂‑eq on a 100-yr basis (26.94 t CO₂‑eq on a 20-yr basis, Table 1). Fossil fuel–powered cars emit 115.3 t CO₂‑eq/million pkm on a 100-yr basis (116.4 t CO₂‑eq/million pkm on a 20-yr basis). The emissions from fossil fuel–powered ICE cars are calculated from the current global fleet mix which is mostly gasoline and diesel powered cars. PHEVs have lower emissions in countries with large shares of renewable, nuclear, or hydropower generation in their electricity grids (International Transport Forum, 2020; Verma et al., 2022).

We found this by collecting data on fuel consumption per kilometer for a range of HEV and PHEV models (International Energy Agency [IEA], 2021; International Transport Forum, 2020) and multiplying it by the emissions intensity of the fuel the vehicle uses (weighting PHEVs for percentage traveled using fuel). Simultaneously, we collected data on electricity consumption for a range of PHEV models (IEA, 2021; International Transport Forum, 2020), and multiplied them by the global average emissions per kWh of electricity generation. This was then weighted by the share of HEVs (73.4%) and PHEVs (26.6%) of the global hybrid car stock.

The amount of emissions savings for PHEVs depends on how often they are charged, the distance traveled using the electric motor, and the emissions intensity of the electrical grid from which they are charged. Hybrid cars today are disproportionately used in high and upper-middle income countries, where electricity grids emit less than the global average per unit of electricity generated (IEA, 2024). HEVs and PHEVs benefit from braking so are more efficient (relative to fossil fuel–powered ICE cars) in urban areas.

Hybrid cars have higher embodied emissions than fossil fuel–powered ICE cars due to the presence of both an ICE and electric motor with a battery that has a GHG-intensive manufacturing process. This gives them a carbon payback period of 2.6 to under 16 years (Alberini et al., 2019; Duncan et al., 2019) for HEVs and as low as one year for PHEVs (Fulton, 2020). Embodied emissions are outside the scope of this assessment. 

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Table 1. Effectiveness at reducing emissions.

Unit: t CO₂‑eq/million pkm, 100-yr basis

25th percentile 19.51
Mean 22.36
Median (50th percentile) 27.11
75th percentile 65.85
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Cost

Hybrid cars cost on average US$0.01 more per pkm (US$7,200/million pkm) than fossil fuel–powered ICE cars, including purchase price, financing, fuel and electricity costs, and maintenance costs. This is based on a population-weighted average of the cost differential between hybrid and fossil fuel–powered ICE cars in the EU and 11 other countries: Argentina, China, Czechia, India, Indonesia, Lithuania, Malaysia, South Africa, Thailand, Ukraine, and the United States (BEUC, 2021; Furch et al., 2022; IEA, 2022; Isenstadt & Slowik, 2025; Lutsey et al., 2021; Mittal & Shah, 2024; Mustapa et al., 2020; Ouyang et al., 2021; Petrauskienė et al., 2021; Suttakul et al., 2022). The hybrid cost is weighted by the share of car stock of HEVs and PHEVs. 

While this analysis found that hybrid cars are slightly more expensive than fossil fuel–powered ICE cars almost everywhere, the margin is often quite small and hybrids are less expensive in China, Czechia, India, Thailand, and the United States.

This amounts to a cost of US$264/t CO₂‑eq on a 100-yr basis (US$266/t CO₂‑eq avoided emissions on a 20-yr basis, Table 2).

This analysis did not include costs that are the same for both hybrid and fossil fuel–powered ICE cars, including taxes, insurance costs, public costs of building road infrastructure, etc.

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Table 2. Cost per unit of climate impact.

Unit: 2023 US$/t CO₂‑eq , 100-yr basis

Median 264
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Learning Curve

Hybrid car prices are declining. For every doubling in hybrid car production, costs decline in accordance with the learning rate of approximately 10% (Table 3).

The learning curve for hybrids is expected to continue its historical trend of 6–17% declines in production costs with each generation (Kittner et al., 2020; Ouyang et al., 2021; Weiss et al., 2019). For hybrid cars, production costs are driven more by the integration of electric and internal combustion powertrain components than by advancements in battery technology. Because they still rely on ICEs, hybrids do not experience the same rapid cost declines from battery improvements as fully electric cars. Instead, their cost reductions stem from manufacturing efficiencies, economies of scale, and advancements in hybrid powertrain efficiency and electric components (Weiss et al., 2019).

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Table 3. Learning rate: drop in cost per doubling of the installed solution base %.

Unit: %

25th percentile 8.00
Mean 11.00
Median (50th percentile) 10.00
75th percentile 13.50
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Speed of Action

Speed of action refers to how quickly a climate solution physically affects the atmosphere after it is deployed. This is different from speed of deployment, which is the pace at which solutions are adopted. 

At Project Drawdown, we define the speed of action for each climate solution as emergency brake, gradual, or delayed.

Mobilize Hybrid Cars is a GRADUAL climate solution. It has a steady, linear impact on the atmosphere. The cumulative effect over time builds as a straight line.

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Caveats

Hybrid cars are often considered a transitional technology for climate change mitigation. While they offer immediate reductions in fuel consumption and emissions compared to fossil fuel–powered ICE cars as the world transitions to fully electric transportation, hybrids still rely on the combustion of fossil fuels. The Mobilize Hybrid Cars solution is a move toward lower emissions – not zero emissions. By combining electric and gasoline powertrains, hybrids improve efficiency and reduce GHG emissions without requiring extensive charging infrastructure, making them a practical short-term solution (IEA, 2021). However, as battery costs decline, renewable energy expands, and charging networks improve, fully electric cars (EVs) are expected to replace hybrids as the dominant low-emission transportation option (Plӧtz et al., 2020).

The effectiveness of hybrid cars in reducing fuel consumption and emissions depends significantly on their ability to use electric power, which is influenced by charging habits and regenerative braking efficiency. PHEVs achieve the greatest fuel savings and emissions reductions when they are regularly charged from a low-emissions-intensity electricity grid because this maximizes their electric driving capability and minimizes reliance on the ICE. However, studies show that real-world charging behaviors vary, with some PHEV users failing to charge frequently, leading to higher-than-expected fuel consumption. Regenerative braking also plays a crucial role because it recaptures kinetic energy during deceleration and converts it into electricity to recharge the battery, improving overall efficiency. The extent of these benefits depends on driving conditions, with stop-and-go urban traffic allowing for more energy recovery than highway driving, where regenerative braking opportunities are limited (Plötz et al., 2020).

Hybrid car adoption faces a major obstacle in the form of constraints on battery production. While electric car battery production is being aggressively upscaled (IEA, 2024), building enough batteries to build enough cars to replace a significant fraction of fossil fuel–powered ICE cars is an enormous challenge. This will likely slow down a transition to hybrids, even if consumer demand is high (Milovanoff et al., 2020). This suggests that EV batteries should be prioritized for users whose transport needs are harder to serve with other forms of low-emissions transportation (such as nonmotorized transportation, public transit, etc.). This could include emergency vehicles, commercial vehicles, and vehicles for people who live in rural areas or have disabilities. 

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Current Adoption

Approximately 12 million PHEVs (IEA, 2024) and more than 33 million HEVs (IEA, 2023) are in use worldwide. This corresponds to about 2.2% of the total car stock of 2,022,057,847 (World Health Organization [WHO], 2022) and means that hybrid cars worldwide travel about 1.3 trillion pkm/yr. We assumed this travel would occur in a fossil fuel–powered ICE car if the car’s occupants did not use a hybrid car. Adoption is much higher in some countries, such as Japan, where the global hybrid car stock share was 20–30% in 2023.

To convert this number into pkm traveled by hybrid car, we need to determine the average passenger-distance that each passenger car travels per year. Using population-weighted data from several different countries, the average car carries 1.5 people and travels about 19,500 vehicle-kilometers (vkm)/yr, or an average of 29,250 pkm/yr. Multiplying this number by the number of hybrid cars in use (48.5 million) gives the total travel distance shifted (1.3 trillion pkm) from fossil fuel–powered ICE cars to hybrid cars (Table 4).

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Table 4. Current (2024) adoption level.

Unit: million pkm/yr

Population-weighted mean 1,318,000

Implied travel shifted from fossil fuel–powered cars to hybrid cars.

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Adoption Trend

Globally, the pkm driven in hybrid cars rather than fossil fuel–powered ICE cars increases by an average of about 178,200 million pkm/yr (Table 5). PHEV car purchases between 2019–2023 grew 45%/yr (IEA, 2024), while HEV purchases increased 10% annually between 2021–2023 (IEA, 2021, 2023). Global purchases of hybrid cars are increasing by around 6.1 million cars/yr. This is based on globally representative data (Bloomberg New Energy Finance [BloombergNEF], 2024; Fortune Business Insights, 2025; IEA, 2024; Menes, 2021).

It is worth noting that despite this impressive rate of growth, hybrid cars still have a long way to go before they replace a large percentage of the more than two billion cars currently driven (WHO, 2022).

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Table 5. 2023–2024 adoption trend.

Unit: million pkm/yr

Population-weighted mean 178,200

Implied travel shifted from fossil fuel–powered cars to hybrid cars.

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Adoption Ceiling

The total adoption ceiling for hybrid cars is equal to the total passenger-distance driven by private cars worldwide. Using a population-weighted mean of the average distance (in pkm) traveled per car annually, this translates to about 59 trillion pkm traveled (Table 6).

Replacing every single fossil fuel–powered ICE passenger car with a hybrid car would require an enormous upscaling of hybrid car production capacity, rapid development of charging infrastructure for PHEVs, cost reductions to make hybrid cars more affordable for more people, and technological improvements to make them more suitable for more kinds of drivers and trips. This shift would also face cultural obstacles from drivers who are attached to fossil fuel–powered cars (Roberts, 2022).

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Table 6. Adoption ceiling.

Unit: million pkm/yr

Population-weighted mean 59,140,000

Implied travel shifted from fossil fuel–powered cars to hybrid cars.

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Achievable Adoption

The achievable adoption of hybrid car travel is about 12-30 trillion pkm shifted from fossil fuel–powered ICE vehicles.

Various organizations have produced forecasts of future hybrid car adoption. These are not assessments of feasible adoption per se; they are instead predictions of likely rates of adoption, given various assumptions about the future (Bloomberg New Energy Finance, 2024; Fortune Business Insights, 2025; IEA, 2021, 2023, 2024). But they are useful in that they take a large number of variables into account. To convert these estimates of future likely adoption into estimates of the achievable adoption range, we applied some optimistic assumptions to the numbers in the scenario projections. 

To find a high rate of hybrid car adoption, we assumed that every country could reach the highest rate of adoption projected to occur for any country. Bloomberg (Bloomberg New Energy Finance, 2024) predicts that some countries will reach 20–50% hybrid vehicle stock share by 2030. We therefore set our high adoption rate at 50% adoption worldwide. This corresponds to 1.011 trillion total hybrid cars in use, or 29.6 trillion pkm traveled by hybrid cars (Table 7). An important caveat is that with a global supply constraint in the production of electric car batteries that are also used by hybrids, per-country adoption rates are somewhat zero-sum. Every hybrid car purchased in Japan is one that cannot be purchased somewhere else. This means that for the whole world to achieve 50% hybrid car stock share, global hybrid car production (especially battery production) would have to radically increase. 

To identify a lower feasible rate of electric car adoption, we took the lower end of Bloomberg’s 20–50% global hybrid car adoption ceiling. This is also the current adoption rate in the most intensive country (Japan at 20%), proving it feasible. This translates to 404 million hybrid cars, or 11.8 trillion pkm traveled by hybrid car.

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Table 7. Range of achievable adoption levels.

Unit: million pkm/yr

Current adoption 1,318,000
Achievable – low 11,830,000
Achievable – high 29,570,000
Adoption ceiling 59,140,000
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Hybrid cars currently displace 0.036 Gt CO₂‑eq/yr of GHG emissions from the transportation system on a 100-yr basis (Table 8; 0.036 Gt CO₂‑eq/yr on a 20-yr basis).

If hybrid cars reach 20% of the global private car stock share as BloombergNEF (2024) projects, then with the current number of cars on the road, they will displace 0.321 Gt CO₂‑eq/yr GHG emissions on a 100-yr basis (0.319 Gt CO₂‑eq/yr on a 20-yr basis).

If hybrid cars globally reach 50% of global private car stock share, as BloombergNEF (2024) estimates might happen in some markets, they will displace 0.802 Gt CO₂‑eq/yr GHG emissions on a 100-yr basis (0.796 Gt CO₂‑eq/yr on a 20-yr basis).

If hybrid cars replace 100% of the global car fleet, they will displace 1.603 Gt CO₂‑eq/yr GHG emissions on a 100-yr basis (1.593 Gt CO₂‑eq/yr on a 20-yr basis).

These numbers are based on the present-day average fuel consumption for hybrids and include emissions intensity from electrical grids for PHEVs. If fuel efficiency continues to improve (including hybrids getting lighter) and grids become cleaner, the total climate impact from hybrids cars will increase.

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Table 8. Climate impact at different levels of adoption.

Unit: Gt CO₂‑eq/yr, 100-yr basis

Current adoption 0.036
Achievable – low 0.321
Achievable – high 0.802
Adoption ceiling 1.603
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Additional Benefits

Air Quality

HEVs and PHEVs cars can reduce emissions of air pollutants, including sulfur oxides, sulfur dioxide, particulate matter, nitrogen oxides, and especially carbon monoxide and volatile organic compounds (Requia et al., 2018). Some air pollution reductions are limited (particularly particulate matter and ozone) because hybrid cars are heavy. The added weight can increase emissions from brakes, tires, and wear on the batteries (Carey, 2023; Jones, 2019).

Health

Because hybrid cars have lower tailpipe emissions than fossil fuel–powered ICE cars, they can reduce traffic-related air pollution, which is associated with asthma, lung cancer, increased emergency department visits for respiratory disease, and increased mortality (Anenberg et al., 2019). Transitioning to hybrid cars can reduce exposure to air pollution, improve health, and prevent premature mortality (Garcia et al., 2023; Larson et al., 2020; Peters et al., 2020).

The health benefits of lower traffic-related air pollution vary spatially and – for PHEVs – partly depend on how communities generate electricity (Choma et al., 2020). Racial and ethnic minority communities located near highways and major traffic corridors are disproportionately exposed to air pollution (Kerr et al., 2021). Transitioning to HEVs and PHEVs could improve health in marginalized urban neighborhoods located near highways, industry, or ports (Pennington et al., 2024). These benefits depend on an equitable distribution of hybrid cars and infrastructure to support the adoption of plug-in hybrid cars (Garcia et al., 2023). 

Income and Work

Adopting hybrid cars can lead to savings in a household’s energy burden spent on fuel, or the proportion of income spent on fuel for transportation (Vega-Perkins et al., 2023). Plug-in hybrids can be charged during off-peak times, leading to further reductions in transportation costs (Romm & Frank, 2006). Savings from HEVs and PHEVs may be especially important for low-income households because they have the highest energy burdens (Bell-Pasht, 2024). 

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Risks

There is some criticism against any solution that advocates for car ownership (electric cars in particular and hybrids – which use fossil fuels – by extension) and that the focus should be on solutions such as public transport systems that reduce car ownership and usage (Jones, 2019; Milovanoff et al., 2020).

There is potential for a rebound effect, where improved fuel efficiency encourages people to drive more, potentially offsetting some of the expected fuel and emissions savings. This can occur because lower fuel costs per kilometer make driving more affordable and so increase vehicle use.

There is a risk that allocating the limited global battery supply to hybrid cars might undermine the deployment of solutions that also require batteries but are more effective at avoiding GHG emissions (Castelvecchi, 2021). These could include electric buses, electric rail, and electric bicycles.

Mining minerals necessary to produce hybrid car batteries carries environmental and social risks. Such mining has been associated with significant harm, particularly in lower-income countries that supply many of these minerals (Agusdinata et al., 2018; Sovacool, 2019).

Hybrid cars might also pose additional safety risks due to their higher weight, which means that they have longer stopping distances and can cause greater damage in collisions and to pedestrians and cyclists (Jones, 2019). 

The operating efficiency depends on charging for PHEVs and braking intensity for all hybrids. The results of efficiency studies also depend on assumptions such as car type, fuel efficiency, battery size, electricity grid, km/yr, and car lifetime. 

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Interactions with Other Solutions

Competing

Hybrid cars compete directly with electric cars for adoption as well as for batteries, public resources, and infrastructural investment.

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Traveling by bicycle, sidewalk, public transit network, fully electric car, or smaller electric vehicle (such as electric bicycle) provides a greater climate benefit than traveling by hybrid car. There is an opportunity cost to deploying hybrid cars because those resources could otherwise be used to support these more effective solutions (Asia-Pacific Economic Cooperation [APEC], 2024).

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Dashboard

Solution Basics

million passenger kilometers (million pkm)

t CO₂-eq (100-yr)/unit
019.5127.11
units/yr
Current 1.318×10⁶ 01.183×10⁷2.957×10⁷
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 0.036 0.3210.802
US$ per t CO₂-eq
264
Gradual

CO₂ , CH₄, N₂O, BC

Trade-offs

Hybrid cars have higher embodied emissions than fossil fuel–powered ICE cars due to the presence of both an ICE and electric motor with a battery that has a GHG-intensive manufacturing process. While the embodied emissions are higher for hybrid cars than ICE cars, coupling them with operating emissions yields a carbon payback period of several years. Embodied emissions were outside the scope of this assessment.

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Mt CO2-eq/yr
0–4
4–8
8–12
12–16
16–20
> 20
No data

Annual road transportation emissions, 2024

Cars are the largest source of vehicle emissions, which are shown here for urban areas.

Kott, T., Foster, K., Villafane-Delgado, M., Loschen, W., Sicurello, P., Ghebreselassie, M., Reilly, E., and Hughes, M. (2024). Transportation sector - Global road emissions [Data set]. The Johns Hopkins University Applied Physics Laboratory (JHU/APL), USA, Climate TRACE Emissions Inventory. Retrieved March 12, 2025 from, Link to source: https://climatetrace.org  

Mt CO2-eq/yr
0–4
4–8
8–12
12–16
16–20
> 20
No data

Annual road transportation emissions, 2024

Cars are the largest source of vehicle emissions, which are shown here for urban areas.

Kott, T., Foster, K., Villafane-Delgado, M., Loschen, W., Sicurello, P., Ghebreselassie, M., Reilly, E., and Hughes, M. (2024). Transportation sector - Global road emissions [Data set]. The Johns Hopkins University Applied Physics Laboratory (JHU/APL), USA, Climate TRACE Emissions Inventory. Retrieved March 12, 2025 from, Link to source: https://climatetrace.org  

Maps Introduction

Hybrid cars can mitigate climate change across a wide range of geographic regions. However, their effectiveness varies due to spatial differences in driving conditions, vehicle usage patterns, the carbon intensity of local fuel mixes, and the carbon intensity of the charging source for plug-in hybrid electric vehicles (PHEVs). Hybrids are most effective in urban environments with stop-and-go traffic. Unlike fully electric cars, hybrids do not depend on external charging infrastructure, making them more immediately viable in areas where transport electrification is a challenge.

Socioeconomic factors, including fuel prices, vehicle taxes, and the availability of incentives, influence the adoption of hybrids. Hybrids may be most attractive in areas with high gasoline prices and underdeveloped electric charging infrastructure. They can be a practical transition technology in countries where civil society or government institutions have not yet mobilized large-scale investments in charging infrastructure.

Hybrid cars have an advantage in hot and cold climates, where battery range degradation and heating/cooling loads might discourage electric car adoption.

Hybrid cars have already experienced high adoption in regions such as Japan and North America. Looking forward, they could be particularly impactful in South and Southeast Asia, where urban congestion and poor air quality make cleaner vehicles highly desirable but electricity infrastructure remains unreliable; Sub-Saharan Africa, where hybrids offer emission reductions without requiring major grid upgrades; and middle-income countries in Latin America and Eastern Europe, where rising car ownership coupled with energy price volatility makes fuel-efficient hybrids more attractive than fossil fuel–powered cars.

Action Word
Mobilize
Solution Title
Hybrid Cars
Classification
Highly Recommended
Lawmakers and Policymakers
  • Create time-bound government procurement policies and targets to transition government fleets to hybrid cars when fully electric cars aren’t possible.
  • Provide financial incentives such as tax breaks, subsidies, or grants for hybrid car production and purchases that gradually reduce as market adoption increases.
  • Provide complimentary benefits for hybrid car drivers, such as privileged parking areas, free tolls, and access schemes.
  • Use targeted financial incentives to help low-income communities buy hybrid cars and incentivize manufacturers to produce more affordable options.
  • Develop charging infrastructure, ensuring adequate spacing between stations and equitable distribution of stations.
  • Invest in R&D or implement regulations to improve manufacturing, adoption, supply chain standards, and circularity of hybrid cars – particularly batteries.
  • Transition fossil fuel electricity production to renewables while promoting the transition to hybrid cars.
  • Disincentivize fossil fuel–powered ICE car ownership by gradually introducing taxes, penalties, buy-back programs, or other mechanisms.
  • Offer one-stop shops for information on hybrid vehicles, including demonstrations and educational resources on cost savings, environmental impact, and maintenance.
  • Work with industry and labor leaders to construct new hybrid car plants and transition fossil fuel–powered ICE car manufacturing into hybrid car production.
  • Set regulations for sustainable use of hybrid car batteries and improve recycling infrastructure.
  • Join international efforts to promote and ensure supply chain environmental and human rights standards.
  • Incentivize or mandate life-cycle assessments and product labeling (e.g., Environmental Product Declarations).
  • Create, support, or join partnerships that offer information, training, and general support for hybrid car adoption.

Further information:

Practitioners
  • Produce and sell affordable hybrid car models.
  • Collaborate with dealers to provide incentives, low-interest financing, or income-based payment options.
  • Develop charging infrastructure, ensuring adequate spacing between stations and equitable distribution of stations.
  • Offer lifetime warranties for hybrid batteries and easy-to-understand maintenance instructions.
  • Invest in R&D to improve manufacturing, adoption, supply chain standards, and circularity of hybrid cars, particularly batteries.
  • Provide customers with real-world data to help alleviate fuel efficiency concerns.
  • Offer one-stop shops for information on hybrid cars, including educational resources on cost savings, environmental impact, optimal charging, and maintenance.
  • Work with policymakers and labor leaders to construct new hybrid car plants and transition fossil fuel–powered ICE car manufacturing into hybrid car production.
  • Join international efforts to promote and ensure supply chain environmental and human rights standards.
  • Invest in recycling and circular economy infrastructure.
  • Conduct life-cycle assessments and ensure product labeling (e.g., Environmental Product Declarations).
  • Create, support, or join partnerships that offer information, training, and general support for hybrid car adoption.

Further information:

Business Leaders
  • Set time-bound company procurement policies and targets to transition corporate fleets to hybrid cars when fully electric cars aren’t feasible and report on these metrics regularly.
  • Encourage supply chain partners to transition their delivery fleets to hybrid vehicles when fully electric cars aren’t feasible.
  • Take advantage of financial incentives, such as tax breaks, subsidies, or grants for hybrid car purchases.
  • Create purchasing agreements with hybrid car manufacturers to support stable demand and improve economies of scale.
  • Install charging stations and offer employee benefits for hybrid car drivers, such as privileged parking areas.
  • Invest in R&D to improve manufacturing, adoption, supply chain standards, and circularity of hybrid cars – particularly batteries.
  • Work with industry and labor leaders to transition fossil fuel–powered ICE car manufacturing into hybrid car production.
  • Advocate for financial incentives and policies that promote hybrid car adoption.
  • Join international efforts to promote and ensure supply chain environmental and human rights standards.
  • Educate employees, customers, and investors about the company's transition to hybrid cars and encourage them to learn more about them.
  • Offer one-stop shops for information on hybrid cars, including demonstrations and educational resources on cost savings, environmental impact, and maintenance.
  • Create, support, or join partnerships that offer information, training, and general support for hybrid car adoption.

Further information:

Nonprofit Leaders
  • Set time-bound organizational procurement policies and targets to transition fleets to hybrid cars when fully electric cars aren’t feasible.
  • Take advantage of financial incentives, such as tax breaks, subsidies, or grants for hybrid car purchases.
  • Advocate for financial incentives and policies that promote hybrid car adoption.
  • Install charging stations and offer employee benefits for hybrid car drivers, such as privileged parking areas.
  • Advocate for or provide improved charging infrastructure.
  • Offer workshops or support to low-income communities for purchasing and owning hybrid cars.
  • Work with industry and labor leaders to transition fossil fuel–powered ICE car manufacturing into hybrid car production.
  • Join international efforts to promote and ensure supply chain environmental and human rights standards.
  • Advocate for regulations on lithium-ion batteries and investments in recycling facilities.
  • Offer one-stop shops for information on hybrid cars, including demonstrations and educational resources on cost savings, environmental impact, and maintenance.
  • Create, support, or join partnerships that offer information, training, and general support for hybrid car adoption.

Further information:

Investors
  • Invest in hybrid car companies and companies that provide charging equipment or installation.
  • Pressure and support portfolio companies in transitioning their corporate fleets.
  • Pressure portfolio companies to establish and report on time-bound targets for corporate fleet transition and roll-out of employee incentives.
  • Invest in R&D to improve manufacturing, adoption, supply chain standards, and circularity of hybrid cars – particularly batteries.
  • Invest in hybrid car companies, associated supply chains, and end-user businesses like rideshare apps.
  • Join international efforts to promote and ensure supply chain environmental and human rights standards.
  • Create, support, or join partnerships that offer information, training, and general support for hybrid car adoption.
  • Offer low-interest loans for purchasing hybrid cars or charging infrastructure.

Further information:

Philanthropists and International Aid Agencies
  • Set time-bound organizational procurement policies to transition fleets to hybrid cars when fully electric cars aren’t feasible.
  • Install charging stations and offer employee benefits for hybrid car drivers, such as privileged parking areas.
  • Take advantage of financial incentives, such as tax breaks, subsidies, or grants for hybrid car purchases.
  • Advocate for financial incentives and policies that promote hybrid car adoption.
  • Advocate for or provide improved charging infrastructure.
  • Advocate for regulations on lithium-ion batteries and public investments in recycling facilities.
  • Offer financial services such as low-interest loans or grants for purchasing hybrid cars and charging equipment.
  • Offer workshops or support to low-income communities for purchasing and owning hybrid cars.
  • Work with industry and labor leaders to transition fossil fuel–powered ICE car manufacturing into hybrid car production.
  • Join international efforts to promote and ensure supply chain environmental and human rights standards.
  • Offer one-stop shops for information on hybrid vehicles, including demonstrations and educational resources on cost savings, environmental impact, and maintenance.
  • Create, support, or join partnerships that offer information, training, and general support for hybrid car adoption.

Further information:

Thought Leaders
  • If purchasing a new car, buy a hybrid car if fully electric isn’t feasible.
  • Take advantage of financial incentives, such as tax breaks, subsidies, or grants for hybrid car purchases.
  • Share your experiences with hybrid cars through social media and peer-to-peer networks, highlighting the cost savings, benefits, incentive programs, and troubleshooting tips.
  • Advocate for financial incentives and policies that promote hybrid car adoption.
  • Advocate for improved charging infrastructure.
  • Help improve circularity of hybrid car supply chains.
  • Conduct in-depth life-cycle assessments of hybrid cars in particular geographies.
  • Research ways to reduce weight and improve the performance of hybrid cars while appealing to customers.
  • Join international efforts to promote and ensure supply chain environmental and human rights standards.
  • Create, support, or join partnerships that offer information, training, and general support for hybrid car adoption.

Further information:

Technologists and Researchers
  • Improve circularity of hybrid car supply chains.
  • Reduce the amount of critical minerals required for hybrid car batteries.
  • Innovate low-cost methods to improve safety, labor standards, and supply chains in mining for critical minerals.
  • Increase the longevity of batteries.
  • Research ways to reduce weight and improve the performance of hybrid cars while appealing to customers.
  • Improve techniques to repurpose used hybrid car batteries for stationary energy storage.
  • Develop methods of adapting fossil fuel–powered car manufacturing and infrastructure to include electric components.

Further information:

Communities, Households, and Individuals
  • If purchasing a new car, buy a hybrid car when fully electric cars aren’t feasible.
  • Take advantage of financial incentives, such as tax breaks, subsidies, or grants for hybrid car purchases.
  • Share your experiences with hybrid cars through social media and peer-to-peer networks, highlighting the cost savings, benefits, incentive programs, and troubleshooting tips.
  • Help shift the narrative around hybrid cars by demonstrating capability and performance.
  • Advocate for financial incentives and policies that promote hybrid car adoption.
  • Advocate for improved charging infrastructure.
  • Help improve circularity of supply chains for hybrid car components.
  • Join international efforts to promote and ensure supply chain environmental and human rights standards.
  • Create, support, or join partnerships that offer information, training, and general support for hybrid car adoption.

Further information:

Sources
Evidence Base

Consensus of effectiveness in reducing GHG emissions: Mixed

There is a high level of consensus that hybrid cars emit fewer GHGs per kilometer traveled compared to fossil fuel–powered ICE cars. Hybrid cars achieve these reductions by combining an ICE with an electric motor that improves fuel efficiency and, for some models, allow for limited all-electric driving, further reducing fuel consumption and emissions. This advantage is strongest in places where trips are short and require a lot of braking, such as in cities. 

Globally, cars and vans were responsible for 3.8 Gt CO₂‑eq emissions in 2023 – more than 60% of road transport emissions (IEA, 2024).

Major climate research organizations generally see hybrid cars as a transitional means of reducing GHG emissions from passenger transportation. These technologies offer immediate emissions reductions while the electricity grid decarbonizes and battery technology improves. Any improvement to fuel efficiency or time spent driving electrically reduces emissions. These technologies can be a gateway to fully electric cars by eliminating range anxiety and allowing drivers the experience of electric driving without fully committing to the limitations of current EV infrastructure. 

Hybrid cars, while more fuel-efficient than fossil fuel–powered ICE cars, still rely on gasoline or diesel (or potentially advanced biofuels), meaning they continue to produce tailpipe emissions and contribute to air pollution. Additionally, their dual powertrains add complexity, leading to higher embodied emissions, manufacturing costs, increased maintenance requirements, and potential long-term reliability concerns. The added weight from both an ICE and an electric motor, along with a battery pack, can reduce overall efficiency and raise safety concerns. Embodied emissions are outside the scope of this assessment.

The International Council on Clean Transportation (ICCT; Isenstadt & Slowik (2025) estimated that HEVs reduce tailpipe GHG emissions by 30% while costing an average of US$2,000 more upfront. Over a 10-yr period, they offered an estimated fuel cost savings of US$4,500. ICCT expected future HEVs to achieve an additional 15% reduction in GHG emissions, with a decrease in the price premium of US$300–800. PHEVs reduce GHG emissions by 11–30%, depending on emissions intensity of the electric grid and the proportion of distance driven electrically. 

The IEA (2024) noted that a PHEV bought in 2023 will emit 30% less GHGs than a fossil fuel–powered ICE car over its lifetime. This includes full life cycle impacts, including those from producing the car. 

The International Transport Forum (2020) estimated that fossil fuel–powered ICE cars emit 162 g CO₂‑eq/pkm while HEVs emit 132 g CO₂‑eq/pkm and PHEVs emit 124 g CO₂‑eq/pkm. This includes embodied and upstream emissions.

The results presented in this document summarize findings from 12 reviews and meta-analyses and 29 original studies reflecting current evidence from 72 countries, primarily from the IEA’s Global Electric Vehicle Outlook (2024) and Electric Vehicles: Total Cost of Ownership Tool (2022) and the International Transport Forum’s life-cycle analysis on sustainable transportation (2020). We recognize this limited geographic scope creates bias, and hope this work inspires research and data sharing on this topic in underrepresented regions.

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Increase Recycling

Submitted by Drawdown Admin on
Sector
Industry, Materials & Waste
Mode
Cut Emissions
Cluster
Use Waste as a Resource
Image
Metal items
Coming Soon
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Summary

Recycling is a mechanical process that repurposes waste into new products without altering their chemical structure. This solution focuses on four common waste types: metals, paper and cardboard, plastics, and glass. It reduces GHG emissions by minimizing reliance on energy-intensive primary material production, reducing demand for raw materials, and diverting paper from landfills, where decomposition can produce methane.

Our focus is on postconsumer municipal solid waste (MSW) collected through residential and commercial recycling programs. Textiles, rubber, wood, and e-waste are also important waste streams but are excluded in our scope due to limited availability of global data. Organic waste is addressed separately in other Drawdown Explorer solutions, including Increase Centralized Composting, Increase Decentralized Composting, and Produce Biochar.

Income & work,Health,Equality
Land resources,Water resources,Air quality
Description for Social and Search
Increase Recycling is a Highly Recommended climate solution, with paper, cardboard, and metals delivering the most greenhouse gas savings.
Overview

Mechanical recycling mitigates GHG emissions by reducing the need for more energy-intensive and pollutant-emitting raw material extraction and processing (Stegmann et al., 2022; Sun et al., 2018; Zier et al., 2021) and reducing production of methane from decomposing paper in landfills (Demetrious & Crossin, 2019; Lee et al., 2017). 

Recyclable materials constitute a significant portion of global MSW, with average compositions of approximately 14% paper and cardboard, 10% plastics, 4% glass, and 3.5% metals (Kaza et al., 2018; United Nations Environment Programme [UNEP], 2024). Recycling reprocesses postconsumer materials into secondary raw materials or products without altering their chemical composition.

Figure 1 illustrates a typical single-stream recycling system at a materials recovery facility (MRF), where mechanical and optical sorting technologies separate materials by type (Gundupalli et al., 2017; Zhang et al., 2022). The sorted materials then undergo cleaning, crushing or shredding, and remelting or repulping in preparation for use in manufacturing new products.

Figure 1. Overview of the separation steps in a materials recycling facility to separate metal, paper and cardboard, plastic, and glass waste. Modified from Waldrop (2020).

Diagram of a recycling facility

Source: Waldrop, M. M. (2020, October 1). Recycling meets reality. Knowable Magazine.

Metals recycling provides ferrous and non-ferrous inputs for the metal production sector, which globally emits an estimated 3.6 Gt CO₂‑eq/yr for 2–3 Gt of primary metal output (Azadi et al., 2020). Virgin (primary) metals are extracted from nonrenewable ores; as higher-grade ores are consumed, mining shifts to lower-grade ore deposits, which require more energy-intensive extraction and processing (Norgate & Jahanshahi, 2011). Using recycled metals in place of virgin metals reduces energy requirements for smelting and refining (Daehn et al., 2022) and water use during production. 

Virgin ore processing primarily emits CO₂, with smaller contributions of methane and nitrous oxide. Some primary metal production, particularly aluminum production, emits fluorinated gases (F-gases) (Raabe et al., 2019; Raabe et al., 2022). Recycling emits significantly less CO₂ than primary material production.

Paper and cardboard recycling involves hydropulping, deinking, and reforming recovered fibers into new paper products. Conventional paper is produced from virgin tree pulp and involves harvesting, debarking, chipping, and mechanical or chemical pulping. Pulp-making alone accounts for 62% of energy use and 45% of emissions in paper production (Sun et al., 2018), contributing significantly to the 1.3–2% of global GHG emissions from virgin pulp and paper manufacturing (Furszyfer Del Rio et al., 2022). Recycling uses less energy and produces fewer GHG emissions. Recycling 1 t of paper saves ~17 mature trees (U.S. Environmental Protection Agency [U.S. EPA], 2016a), lessening deforestation from harvesting and reducing the energy and water required for pulping. Recovering used paper from landfills further avoids decomposition-related methane release.

Plastics recycling involves melting plastic waste into resin, forming it into granules or pellets, and using it to manufacture new products. The primary material production of plastics represents 4.5–5.3% of total global GHG emissions (Cabernard et al., 2022; Karali et al., 2024), with ~75% occurring in the early life-cycle stages. More than 99% of plastics are derived from fossil fuels. Recycling plastics reduces CO₂ and methane emissions by replacing petroleum-based feedstock with recycled plastic. 

Glass recycling crushes glass waste into cullet, which can then be melted and reintroduced as a raw material in glass manufacturing. Virgin glass production requires melting raw materials such as silica sand, soda ash, and limestone at ~1,500 °C (Baek et al., 2025; Westbroek et al., 2021) and releases CO₂ from decomposition of carbonates. Cullet use releases no CO₂ from carbonate decomposition and lowers the melting temperature, reducing furnace fuel combustion. 

This assessment evaluates metal, paper and cardboard, plastic, and glass recycling separately to better capture the distinct emissions profiles and cost requirements of each material, providing a clearer understanding of the climate benefits and trade-offs. 

Allwood, J. M., Music, O., Loukaides, E. G., & Bambach, M. (2025). Cut the scrap: Making more use of less metal. CIRP Annals, 74(2), 895–919. Link to source: https://doi.org/10.1016/j.cirp.2025.04.013 

Aparcana, S., & Salhofer, S. (2013). Development of a social impact assessment methodology for recycling systems in low-income countries. The International Journal of Life Cycle Assessment, 18(5), 1106–1115. Link to source: https://doi.org/10.1007/s11367-013-0546-8

Awino, F. B., & Apitz, S. E. (2024). Solid waste management in the context of the waste hierarchy and circular economy frameworks: An international critical review. Integrated Environmental Assessment and Management, 20(1), 9–35. Link to source: https://doi.org/10.1002/ieam.4774

Ayodele, T. R., Alao, M. A., & Ogunjuyigbe, A. S. O. (2018). Recyclable resources from municipal solid waste: Assessment of its energy, economic and environmental benefits in Nigeria. Resources, Conservation and Recycling, 134, 165–173. Link to source: https://doi.org/10.1016/j.resconrec.2018.03.017

Azadi, M., Northey, S. A., Ali, S. H., & Edraki, M. (2020). Transparency on greenhouse gas emissions from mining to enable climate change mitigation. Nature Geoscience, 13(2), 100–104. Link to source: https://doi.org/10.1038/s41561-020-0531-3

Baek, C. R., Kim, H. D., & Jang, Y.-C. (2025). Exploring glass recycling: Trends, technologies, and future trajectories. Environmental Engineering Research, 30(3), Article 240241. Link to source: https://doi.org/10.4491/eer.2024.241

Bajpai, P. (2014). Introduction. In Recycling and deinking of recovered paper (pp. 1–18). Elsevier. Link to source: https://doi.org/10.1016/B978-0-12-416998-2.00001-5

Barbato, P. M., Olsson, E., & Rigamonti, L. (2024). Quality degradation in glass recycling: Substitutability model proposal. Waste Management, 182, 124–131. Link to source: https://doi.org/10.1016/j.wasman.2024.04.027

Barford, A., & Beales, A. (2025, April 3). Decent work opportunities and challenges in recycling [ILO Technical brief]. International Labour Organization. Link to source: https://www.ilo.org/publications/decent-work-opportunities-and-challenges-recycling 

Bauer, F., Nielsen, T. D., Nilsson, L. J., Palm, E., Ericsson, K., Fråne, A., & Cullen, J. (2022). Plastics and climate change—Breaking carbon lock-ins through three mitigation pathways. One Earth, 5(4), 361–376. Link to source: https://doi.org/10.1016/j.oneear.2022.03.007

Berardocco, C., Delawter, H., Putzu, T., Wolfe, L. C., & Zhang, H. (2022). Life cycle sustainability assessment of single stream and multi-stream waste recycling systems. Sustainability, 14(24), Article 16747. Link to source: https://doi.org/10.3390/su142416747 

BioCubes. (n.d.). BioCubes: An inventory of biomass and technomass [Interactive infographic]. Retrieved August 8, 2025, from Link to source: https://biocubes.net/ 

Bogner, J., Abdelrafie Ahmed, M., Díaz, C., Faaij, A., Gao, Q., Hashimoto, S., Marecková, K., Pipatti, R., & Zhang, T. (2007). Waste management. In B. Metz, O. R. Davidson, P. R. Bosch, R. Dave, & L. A. Meyer (Eds.), Climate change 2007: Mitigation. Working group III contribution to the fourth assessment report of the intergovernmental panel on climate change (pp. 585–618). Cambridge University Press. Link to source: https://www.ipcc.ch/site/assets/uploads/2018/02/ar4-wg3-chapter10-1.pdf

Burinskienė, A., Lingaitienė, O., & Byčenkaitė, G. (2025). Dynamics of trade of recycled raw materials and the connection with the circular economy. Discover Sustainability, 6, Article  680. Link to source: https://doi.org/10.1007/s43621-025-01502-4

Cabernard, L., Pfister, S., Oberschelp, C., & Hellweg, S. (2022). Growing environmental footprint of plastics driven by coal combustion. Nature Sustainability, 5(2), 139–148. Link to source: https://doi.org/10.1038/s41893-021-00807-2

Campbell, R., Bond, D. E., Connellan, C., Mohen, P., & Foo, J. (2022, May 5). From trash to treasure: Green metals from recycling [Insight]. White & Case. Link to source: https://www.whitecase.com/insight-our-thinking/trash-treasure-green-metals-recycling 

Chamas, A., Moon, H., Zheng, J., Qiu, Y., Tabassum, T., Jang, J. H., Abu-Omar, M., Scott, S. L., & Suh, S. (2020). Degradation rates of plastics in the environment. ACS Sustainable Chemistry & Engineering, 8(9), 3494–3511. Link to source: https://doi.org/10.1021/acssuschemeng.9b06635

Charpentier Poncelet, A., Helbig, C., Loubet, P., Beylot, A., Muller, S., Villeneuve, J., Laratte, B., Thorenz, A., Tuma, A., & Sonnemann, G. (2022). Losses and lifetimes of metals in the economy. Nature Sustainability, 5(8), 717–726. Link to source: https://doi.org/10.1038/s41893-022-00895-8

Chen, D. M.-C., Bodirsky, B. L., Krueger, T., Mishra, A., & Popp, A. (2020). The world’s growing municipal solid waste: Trends and impacts. Environmental Research Letters, 15(7), Article 074021. Link to source: https://doi.org/10.1088/1748-9326/ab8659

Ciacci, L., Harper, E. M., Nassar, N. T., Reck, B. K., & Graedel, T. E. (2016). Metal dissipation and inefficient recycling intensify climate forcing. Environmental Science & Technology, 50(20), 11394–11402. Link to source: https://doi.org/10.1021/acs.est.6b02714 

Close the Glass Loop. (2025, July 1). Overview of glass packaging collection systems in Europe. Link to source: https://closetheglassloop.eu/overview-of-glass-packaging-collection-systems-in-europe/

Colangelo, S. (2024). Reducing the environmental footprint of glass manufacturing. International Journal of Applied Glass Science, 15(4), 350–366. Link to source: https://doi.org/10.1111/ijag.16674

Cudjoe, D., Zhu, B., Nketiah, E., Wang, H., Chen, W., & Qianqian, Y. (2021). The potential energy and environmental benefits of global recyclable resources. Science of The Total Environment, 798, Article 149258. Link to source: https://doi.org/10.1016/j.scitotenv.2021.149258

Daehn, K., Basuhi, R., Gregory, J., Berlinger, M., Somjit, V., & Olivetti, E. A. (2022). Innovations to decarbonize materials industries. Nature Reviews Materials, 7(4), 275–294. Link to source: https://doi.org/10.1038/s41578-021-00376-y

Damgaard, A., Larsen, A. W., & Christensen, T. H. (2009). Recycling of metals: Accounting of greenhouse gases and global warming contributions. Waste Management & Research, 27(8), 773–780. Link to source: https://doi.org/10.1177/0734242X09346838

Das, S. K., Green, J. A. S., & Kaufman, J. G. (2010, February). Aluminum recycling: Economic and environmental benefits. Light Metal Age, 22–24. Link to source: https://static1.squarespace.com/static/5fecb6479b54c51485875e10/t/60ac1db2e0db640cb17e0eef/1621892530735/Aluminum+Recycling_+Economic+and+Environmental+...+-+Phinix%2C+LLC.pdf 

DebRoy, T., & Elmer, J. W. (2024). Metals beyond tomorrow: Balancing supply, demand, sustainability, substitution, and innovations. Materials Today, 80, 737–757. Link to source: https://doi.org/10.1016/j.mattod.2024.09.007

Deer, R. (2021, May 5). Why is glass recycling going away? Roadrunner Waste & Recycling. Link to source: https://www.roadrunnerwm.com/blog/why-is-glass-recycling-going-away

Delbari, S. A., & Hof, L. A. (2024). Glass waste circular economy—Advancing to high-value glass sheets recovery using industry 4.0 and 5.0 technologies. Journal of Cleaner Production, 462, Article 142629. Link to source: https://doi.org/10.1016/j.jclepro.2024.142629

Demetrious, A., & Crossin, E. (2019). Life cycle assessment of paper and plastic packaging waste in landfill, incineration, and gasification-pyrolysis. Journal of Material Cycles and Waste Management, 21(4), 850–860. Link to source: https://doi.org/10.1007/s10163-019-00842-4

de Sa, P., & Korinek, J. (2021, March 1). Resource efficiency, the circular economy, sustainable materials management and trade in metals and minerals (OECD Trade Policy Paper No. 245). OECD Publishing. Link to source: https://doi.org/10.1787/69abc1bd-en

Diaz, R., & Warith, M. (2006). Life-cycle assessment of municipal solid wastes: Development of the WASTED model. Waste Management, 26(8), 886–901. Link to source: https://doi.org/10.1016/j.wasman.2005.05.007

Dokl, M., Copot, A., Krajnc, D., Fan, Y. V., Vujanović, A., Aviso, K. B., Tan, R. R., Kravanja, Z., & Čuček, L. (2024). Global projections of plastic use, end-of-life fate and potential changes in consumption, reduction, recycling and replacement with bioplastics to 2050. Sustainable Production and Consumption, 51, 498–518. Link to source: https://doi.org/10.1016/j.spc.2024.09.025

Dong, X., Song, J., & Duan, H. (2022). Prioritizing countries for implementing waste recycling under socioeconomic support. Journal of Environmental Management, 322, Article  116158. Link to source: https://doi.org/10.1016/j.jenvman.2022.116158

Dussaux, D., & Glachant, M. (2019). How much does recycling reduce imports? Evidence from metallic raw materials. Journal of Environmental Economics and Policy, 8(2), 128–146. Link to source: https://doi.org/10.1080/21606544.2018.1520650

Egger, P. H., & Keuschnigg, C. (2024). Resource dependence, recycling, and trade. Journal of Environmental Economics and Management, 128, Article 103064. Link to source: https://doi.org/10.1016/j.jeem.2024.103064

European Paper Recycling Council. (2024). European declaration on paper recycling 2021-2030: Monitoring report 2023. Confederation of European Paper Industries. Link to source: https://www.cepi.org/wp-content/uploads/2024/11/24-4378_EPRC_2023_Singlepages.pdf

Ferdous, W., Manalo, A., Siddique, R., Mendis, P., Zhuge, Y., Wong, H. S., Lokuge, W., Aravinthan, T., & Schubel, P. (2021). Recycling of landfill wastes (tyres, plastics and glass) in construction – A review on global waste generation, performance, application and future opportunities. Resources, Conservation and Recycling, 173, Article 105745. Link to source: https://doi.org/10.1016/j.resconrec.2021.105745

Food and Agriculture Organization of the United Nations. (n.d.). FAO‑FAOSTAT: Forestry production and trade [Data set]. Retrieved April 25, 2025, from Link to source: https://www.fao.org/faostat/en/#data/FO/visualize 

Food and Agriculture Organization of the United Nations. (2009). Global demand for wood products. In State of the world’s forests 2009 (pp. 62–73). Link to source: https://www.fao.org/4/i0350e/i0350e02a.pdf 

Furszyfer Del Rio, D. D., Sovacool, B. K., Griffiths, S., Bazilian, M., Kim, J., Foley, A. M., & Rooney, D. (2022). Decarbonizing the pulp and paper industry: A critical and systematic review of sociotechnical developments and policy options. Renewable and Sustainable Energy Reviews, 167, Article 112706. Link to source: https://doi.org/10.1016/j.rser.2022.112706

Gailani, A., Cooper, S., Allen, S., Pimm, A., Taylor, P., & Gross, R. (2024). Assessing the potential of decarbonization options for industrial sectors. Joule, 8(3), 576–603. Link to source: https://doi.org/10.1016/j.joule.2024.01.007

Geyer, R., Kuczenski, B., Zink, T., & Henderson, A. (2016). Common misconceptions about recycling. Journal of Industrial Ecology, 20(5), 1010–1017. Link to source: https://doi.org/10.1111/jiec.12355

Glass Packaging Institute. (n.d.). Facts about glass recycling. Retrieved March 24, 2025, from Link to source: https://www.gpi.org/facts-about-glass-recycling 

Gorman, M. R., Dzombak, D. A., & Frischmann, C. (2022). Potential global GHG emissions reduction from increased adoption of metals recycling. Resources, Conservation and Recycling, 184, Article 106424. Link to source: https://doi.org/10.1016/j.resconrec.2022.106424

Gundupalli, S. P., Hait, S., & Thakur, A. (2017). A review on automated sorting of source-separated municipal solid waste for recycling. Waste Management, 60, 56–74. Link to source: https://doi.org/10.1016/j.wasman.2016.09.015

Guo, J., Ali, S., & Xu, M. (2023). Recycling is not enough to make the world a greener place: Prospects for the circular economy. Green Carbon, 1(2), 150–153. Link to source: https://doi.org/10.1016/j.greenca.2023.10.006 

Halog, A., & Anieke, S. (2021). A review of circular economy studies in developed countries and its potential adoption in developing countries. Circular Economy and Sustainability, 1(1), 209–230. Link to source: https://doi.org/10.1007/s43615-021-00017-0

Hendrickson, T. P., Bose, B., Vora, N., Huntington, T., Nordahl, S. L., Helms, B. A., & Scown, C. D. (2024). Paths to circularity for plastics in the United States. One Earth, 7(3), 520–531. Link to source: https://doi.org/10.1016/j.oneear.2024.02.005

Houssini, K., Li, J., & Tan, Q. (2025). Complexities of the global plastics supply chain revealed in a trade-linked material flow analysis. Communications Earth & Environment, 6(1), Article 257. Link to source: https://doi.org/10.1038/s43247-025-02169-5

International Paper. (n.d.). Paper’s life cycle: The recycling process [Infographic]. Retrieved June 10, 2025, from Link to source: https://www.internationalpaper.com/resources/infographic/papers-life-cycle-recycling-process

Karali, N., Khanna, N., & Shah, N. (2024). Climate impact of primary plastic production. Lawrence Berkeley National Laboratory. Link to source: https://escholarship.org/uc/item/6cc1g99q

Kaza, S., Yao, L. C., Bhada-Tata, P., & Van Woerden, F. (2018). What a waste 2.0: A global snapshot of solid waste management to 2050. Urban Development Series. Washington, DC: World Bank. Link to source: https://hdl.handle.net/10986/30317 

Klotz, M., Haupt, M., & Hellweg, S. (2022). Limited utilization options for secondary plastics may restrict their circularity. Waste Management, 141, 251–270. Link to source: https://doi.org/10.1016/j.wasman.2022.01.002

Klotz, M., Haupt, M., & Hellweg, S. (2023). Potentials and limits of mechanical plastic recycling. Journal of Industrial Ecology, 27(4), 1043–1059. Link to source: https://doi.org/10.1111/jiec.13393

Lee, U., Han, J., & Wang, M. (2017). Evaluation of landfill gas emissions from municipal solid waste landfills for the life-cycle analysis of waste-to-energy pathways. Journal of Cleaner Production, 166, 335–342. Link to source: https://doi.org/10.1016/j.jclepro.2017.08.016

Li, H., Aguirre-Villegas, H. A., Allen, R. D., Bai, X., Benson, C. H., Beckham, G. T., Bradshaw, S. L., Brown, J. L., Brown, R. C., Cecon, V. S., Curley, J. B., Curtzwiler, G. W., Dong, S., Gaddameedi, S., García, J. E., Hermans, I., Kim, M. S., Ma, J., Mark, L. O., … Huber, G. W. (2022). Expanding plastics recycling technologies: Chemical aspects, technology status and challenges. Green Chemistry, 24(23), 8899–9002. Link to source: https://doi.org/10.1039/D2GC02588D

Liu, Y., Park, S., Yi, H., & Feiock, R. (2020). Evaluating the employment impact of recycling performance in Florida. Waste Management, 101, 283–290. Link to source: https://doi.org/10.1016/j.wasman.2019.10.025

Maximize Market Research Private Limited. (2025). Glass recycling market – Global market forecast and growth opportunities: Forecast 2025–2032 [Report summary]. Link to source: https://www.maximizemarketresearch.com/market-report/glass-recycling-market/22548/ 

McGinty, D. B. (2021, February 3). 5 opportunities of a circular economy. World Resources Institute. Link to source: https://www.wri.org/insights/5-opportunities-circular-economy 

Miserocchi, L., Franco, A., & Testi, D. (2024). Status and prospects of energy efficiency in the glass industry: Measuring, assessing and improving energy performance. Energy Conversion and Management: X, 24, Article 100720. https://doi.org/10.1016/j.ecmx.2024.100720

Monclús, L., Arp, H. P. H., Groh, K. J., Faltynkova, A., Løseth, M. E., Muncke, J., Wang, Z., Wolf, R., Zimmermann, L., & Wagner, M. (2025). Mapping the chemical complexity of plastics. Nature, 643(8071), 349–355. Link to source: https://doi.org/10.1038/s41586-025-09184-8

Nayanathara Thathsarani Pilapitiya, P. G. C., & Ratnayake, A. S. (2024). The world of plastic waste: A review. Cleaner Materials, 11, Article 100220. Link to source: https://doi.org/10.1016/j.clema.2024.100220

Ng, K. S., & Phan, A. N. (2021). Evaluating the techno-economic potential of an integrated material recovery and waste-to-hydrogen system. Resources, Conservation and Recycling, 167, Article 105392. Link to source: https://doi.org/10.1016/j.resconrec.2020.105392

NIH Environmental Management System. (n.d.). Benefits of recycling. U.S. Department of Health and Human Services, National Institutes of Health. Retrieved August 26, 2025, from Link to source: https://nems.nih.gov/environmental-programs/pages/benefits-of-recycling.aspx 

Nordahl, S. L., & Scown, C. D. (2024). Recommendations for life‑cycle assessment of recyclable plastics in a circular economy. Chemical Science, 15, 9397–9407. Link to source: https://doi.org/10.1039/D4SC01340A

Norgate, T., & Jahanshahi, S. (2011). Reducing the greenhouse gas footprint of primary metal production: Where should the focus be? Minerals Engineering, 24(14), 1563–1570. Link to source: https://doi.org/10.1016/j.mineng.2011.08.007

Obradovic, D., & Mishra, L. N. (2020). Mechanical properties of recycled paper and cardboard. The Journal of Engineering and Exact Sciences, 6(3), 0429–0434. Link to source: https://doi.org/10.18540/jcecvl6iss3pp0429-0434

Olafasakin, O., Ma, J., Bradshaw, S. L., Aguirre-Villegas, H. A., Benson, C., Huber, G. W., Zavala, V. M., & Mba-Wright, M. (2023). Techno-economic and life cycle assessment of standalone single-stream material recovery facilities in the United States. Waste Management, 166, 368–376. Link to source: https://doi.org/10.1016/j.wasman.2023.05.011

Oo, P. Z., Prapaspongsa, T., Strezov, V., Huda, N., Oshita, K., Takaoka, M., Ren, J., Halog, A., & Gheewala, S. H. (2024). The role of global waste management and circular economy towards carbon neutrality. Sustainable Production and Consumption, 52, 498–510. Link to source: https://doi.org/10.1016/j.spc.2024.11.021

Organisation for Economic Co‑operation and Development. (2022a). Global plastics outlook database [Data set]. Link to source: https://data-explorer.oecd.org/vis?tm=recycled%20plastics&pg=0&hc[Measure]=&hc[Plastic%20end-of-life%20fate]=&snb=13&df[ds]=dsDisseminateFinalDMZ&df[id]=DSD_PW%40DF_PW&df[ag]=OECD.ENV.EEI&df[vs]=1.0&dq=..A.REC.&pd=1990%2C2019&to[TIME_PERIOD]=false&vw=tb 

Organisation for Economic Co‑operation and Development. (2022b). Global plastics outlook: Economic drivers, environmental impacts and policy options [Report]. OECD Publishing. Link to source: https://doi.org/10.1787/de747aef-en 

Pivnenko, K., Laner, D., & Astrup, T. F. (2016). Material cycles and chemicals: Dynamic material flow analysis of contaminants in paper recycling. Environmental Science & Technology, 50(22), 12302–12311. Link to source: https://doi.org/10.1021/acs.est.6b01791

Plastics Europe. (2022). Plastics – the facts 2022 [Report]. Link to source: https://plasticseurope.org/knowledge-hub/plastics-the-facts-2022/ 

Plastics Europe. (2023). Plastics – the fast facts 2023 [Infographic]. Link to source: https://plasticseurope.org/knowledge-hub/plastics-the-fast-facts-2023/ 

Plastics Europe. (2024a). Plastics – the fast facts 2024 [Infographic]. Link to source: https://plasticseurope.org/knowledge-hub/plastics-the-fast-facts-2024/ 

Plastics Europe. (2024b). The circular economy for plastics – A European analysis 2024 [Report]. Link to source: https://plasticseurope.org/knowledge-hub/the-circular-economy-for-plastics-a-european-analysis-2024/ 

Raabe, D., Tasan, C. C., & Olivetti, E. A. (2019). Strategies for improving the sustainability of structural metals. Nature, 575(7781), 64–74. Link to source: https://doi.org/10.1038/s41586-019-1702-5

Raabe, D., Ponge, D., Uggowitzer, P. J., Roscher, M., Paolantonio, M., Liu, C., Antrekowitsch, H., Kozeschnik, E., Seidmann, D., Gault, B., De Geuser, F., Deschamps, A., Hutchinson, C., Liu, C., Li, Z., Prangnell, P., Robson, J., Shanthraj, P., Vakili, S., … Pogatscher, S. (2022). Making sustainable aluminum by recycling scrap: The science of “dirty” alloys. Progress in Materials Science, 128, Article 100947. Link to source: https://doi.org/10.1016/j.pmatsci.2022.100947

Rajmohan, K. V. S., Ramya, C., Raja Viswanathan, M., & Varjani, S. (2019). Plastic pollutants: Effective waste management for pollution control and abatement. Current Opinion in Environmental Science & Health, 12, 72–84. Link to source: https://doi.org/10.1016/j.coesh.2019.08.006

Rigamonti, L., Taelman, S. E., Huysveld, S., Sfez, S., Ragaert, K., & Dewulf, J. (2020). A step forward in quantifying the substitutability of secondary materials in waste management life cycle assessment studies. Waste Management, 114, 331–340. Link to source: https://doi.org/10.1016/j.wasman.2020.07.015

Rissman, J., Bataille, C., Masanet, E., Aden, N., Morrow, W. R., Zhou, N., Elliott, N., Dell, R., Heeren, N., Huckestein, B., Cresko, J., Miller, S. A., Roy, J., Fennell, P., Cremmins, B., Koch Blank, T., Hone, D., Williams, E. D., de la Rue du Can, S., … Helseth, J. (2020). Technologies and policies to decarbonize global industry: Review and assessment of mitigation drivers through 2070. Applied Energy, 266, Article 114848. Link to source: https://doi.org/10.1016/j.apenergy.2020.114848

Singh, N., & Walker, T. R. (2024). Plastic recycling: A panacea or environmental pollution problem. npj Materials Sustainability, 2, Article 17. Link to source: https://doi.org/10.1038/s44296-024-00024-w

Sobhani, Z., & Palanisami, T. (2025). Emerging contaminants in organic recycling: Role of paper and pulp packaging. Resources, Conservation & Recycling, 215, Article 108070. Link to source: https://doi.org/10.1016/j.resconrec.2024.108070

Stegmann, P., Daioglou, V., Londo, M., van Vuuren, D. P., & Junginger, M. (2022). Plastic futures and their CO2 emissions. Nature, 612(7939), 272–276. Link to source: https://doi.org/10.1038/s41586-022-05422-5

Sun, M., Wang, Y., Shi, L., & Klemeš, J. J. (2018). Uncovering energy use, carbon emissions and environmental burdens of pulp and paper industry: A systematic review and meta-analysis. Renewable and Sustainable Energy Reviews, 92, 823–833. Link to source: https://doi.org/10.1016/j.rser.2018.04.036 

Uekert, T., Singh, A., DesVeaux, J. S., Ghosh, T., Bhatt, A., Yadav, G., Afzal, S., Walzberg, J., Knauer, K. M., Nicholson, S. R., Beckham, G. T., & Carpenter, A. C. (2023). Technical, economic, and environmental comparison of closed-loop recycling technologies for common plastics. ACS Sustainable Chemistry & Engineering, 11(3), 965–978. Link to source: https://doi.org/10.1021/acssuschemeng.2c05497

United Nations Environment Programme. (2024). Global waste management outlook 2024: Beyond an age of waste – Turning rubbish into a resource [Report]. United Nations Environment Programme & International Solid Waste Association. Link to source: https://www.unep.org/resources/global-waste-management-outlook-2024

United Nations Office on Drugs and Crime. (2023, April 4). Unwaste trendspotting alert no. 4: Paper and cardboard waste [Bulletin]. Link to source: https://www.unodc.org/res/environment-climate/asia-pacific/unwaste_html/Unwaste_Trendspotting_Alert_No.4.pdf

U.S. Geological Survey. (2021) Mineral commodity summaries 2021. Link to source: https://doi.org/10.3133/mcs2021 

U.S. Geological Survey. (2022). Iron and steel scrap. In Mineral commodity summaries 2022 (pp. 90–91). Link to source: https://doi.org/10.3133/mcs2022 

U.S. Environmental Protection Agency. (2016a). Environmental factoids [Archived]. U.S. Environmental Protection Agency WasteWise Program. Retrieved March 24, 2025, from Link to source: https://archive.epa.gov/epawaste/conserve/smm/wastewise/web/html/factoid.html 

U.S. Environmental Protection Agency. (2016b). Greenhouse gas inventory guidance: Direct emissions from stationary combustion sources. Link to source: https://www.epa.gov/sites/default/files/2016-03/documents/stationaryemissions_3_2016.pdf 

U.S. Environmental Protection Agency. (2025). Recycling basics and benefits. Retrieved September 2, 2025, from Link to source: https://www.epa.gov/recycle/recycling-basics-and-benefits 

Valenzuela-Levi, N., Araya-Córdova, P. J., Dávila, S., & Vásquez, Ó. C. (2021). Promoting adoption of recycling by municipalities in developing countries: Increasing or redistributing existing resources? Resources, Conservation and Recycling, 164, Article 105173. Link to source: https://doi.org/10.1016/j.resconrec.2020.105173

van Ewijk, S., Stegemann, J. A., & Ekins, P. (2021). Limited climate benefits of global recycling of pulp and paper. Nature Sustainability, 4(2), 180–187. Link to source: https://doi.org/10.1038/s41893-020-00624-z

van Ewijk, S., & Stegemann, J. A. (2023). Waste recycling. In An introduction to waste management and circular economy (pp. 217–254). UCL Press. Link to source: https://doi.org/10.14324/111.9781800084650

Waldrop, M. M. (2020, October 1). Recycling meets reality. Knowable Magazine. Link to source: https://knowablemagazine.org/content/article/food-environment/2020/recycling-meets-reality-feature

Watari, T., Fishman, T., Wieland, H., & Wiedenhofer, D. (2025). Global stagnation and regional variations in steel recycling. Resources, Conservation & Recycling, 220, Article 108363. Link to source: https://doi.org/10.1016/j.resconrec.2025.108363

Westbroek, C. D., Bitting, J., Craglia, M., Azevedo, J. M. C., & Cullen, J. M. (2021). Global material flow analysis of glass: From raw materials to end of life. Journal of Industrial Ecology, 25(2), 333–343. Link to source: https://doi.org/10.1111/jiec.13112

World Bank. (2018). What a waste global database: Country-level dataset (Last updated: 2024, June 4) [Data set]. Link to source: https://datacatalogfiles.worldbank.org/ddh-published/0039597/3/DR0049199/country_level_data.csv 

World Wildlife Fund. (2023). Who pays for plastic pollution? [Report]. Link to source: https://www.worldwildlife.org/documents/671/6lohrny0o2_ENGLISH_WWF_ENABLING_GLOBAL_EQUITY_WEBV.pdf 

Yang, H., Ma, M., Thompson, J. R., & Flower, R. J. (2018). Waste management, informal recycling, environmental pollution and public health. Journal of Epidemiology and Community Health, 72(3), 237–243. Link to source: https://doi.org/10.1136/jech-2016-208597

Yokoi, R., Watari, T., & Motoshita, M. (2022). Future greenhouse gas emissions from metal production: Gaps and opportunities towards climate goals. Energy & Environmental Science, 15(1), 146–157. Link to source: https://doi.org/10.1039/D1EE02165F

Yuan, X., Wang, J., Song, Q., & Xu, Z. (2024). Integrated assessment of economic benefits and environmental impact in waste glass closed‑loop recycling for promoting glass circularity. Journal of Cleaner Production, 444, Article 141155. https://doi.org/10.1016/j.jclepro.2024.141155

Zhang, X., Liu, C., Chen, Y., Zheng, G., & Chen, Y. (2022). Source separation, transportation, pretreatment, and valorization of municipal solid waste: A critical review. Environment, Development and Sustainability, 24(10), 11471–11513. Link to source: https://doi.org/10.1007/s10668-021-01932-w

Zheng, J., & Suh, S. (2019). Strategies to reduce the global carbon footprint of plastics. Nature Climate Change, 9(5), 374–378. Link to source: https://doi.org/10.1038/s41558-019-0459-z

Zhou, X., Zhang, H., Zheng, S., & Xing, W. (2022). The global recycling trade for twelve critical metals: Based on trade pattern and trade quality analysis. Sustainable Production and Consumption, 33, 831–845. Link to source: https://doi.org/10.1016/j.spc.2022.08.011

Zhu, X., Konik, J., & Kaufman, H. (2025). The knowns and unknowns in our understanding of how plastics impact climate change: A systematic review. Frontiers in Environmental Science, 13, Article 1563488. Link to source: https://doi.org/10.3389/fenvs.2025.1563488 

Zier, M., Stenzel, P., Kotzur, L., & Stolten, D. (2021). A review of decarbonization options for the glass industry. Energy Conversion and Management: X, 10, Article 100083. Link to source: https://doi.org/10.1016/j.ecmx.2021.100083

Credits

Lead Fellow

  • Nina-Francesca Farac, Ph.D.

Contributors

  • Ruthie Burrows, Ph.D.

  • James Gerber, Ph.D.

  • Daniel Jasper

  • Alex Sweeney

Internal Reviewers

  • Emily Cassidy

  • Megan Matthews, Ph.D.

  • Christina Swanson, Ph.D.

Effectiveness

We estimated recycling effectiveness as the net emissions savings from avoided primary manufacturing and landfilling, minus the emissions associated with recycling, as outlined in Equation 1 (see Climate Impact for more information on technical substitutability ratios [TSRs]). We included landfilling emissions only for materials that generate meaningful end-of-life GHG impacts. Paper and cardboard emit both biogenic CO₂ and methane emissions from anaerobic decomposition (Lee et al., 2017), and plastics contribute minor emissions from landfill handling due to their inert nature (Chamas et al., 2020; Zheng & Suh, 2019). Metals and glass are also considered inert and do not biodegrade. Their landfilling emissions are primarily from collection and transport, which fall outside the scope of this analysis.

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Equation 1.

$$Effectiveness = ([Primary\ manufacturing_{emissions} \times TSR]\ + \ Landfilling_{emissions})\ - \ Recycling_{emissions}$$

Metals recycling has a high carbon abatement potential of 1,480,000 t CO₂‑eq /Mt metal waste recycled (1,650,000 t CO₂‑eq /Mt metal waste recycled, 20-year basis) (Table 1a). In our analysis, metal recycling emissions were about one-third of those from primary metal production. 

Paper and cardboard recycling has a similar carbon abatement potential of 1,000,000 t CO₂‑eq /Mt paper and cardboard waste recycled (1,000,000 t CO₂‑eq /Mt paper and cardboard waste recycled, 20-year basis) (Table 1b). Although recycling lowers fossil fuel use in pulping, our estimates showed only slightly lower emissions than primary manufacturing. In contrast, preventing CO₂ and methane release from decomposing paper in landfills have comparable emissions to primary paper production, making landfill diversion the larger climate impact.

Plastics recycling is the most effective of the four materials at reducing emissions, eliminating approximately 2,000,000 t CO₂‑eq /Mt plastic waste recycled (3,000,000 t CO₂‑eq /Mt plastic waste recycled, 20-year basis) (Table 1c). This is largely due to the high emissions intensity of virgin plastic production, which reached global production volumes of 374 Mt in 2023 (Plastics Europe, 2024a) and relies heavily on fossil fuels both as feedstocks and as energy sources for heat generation. While pellet-to-product conversion contributes to overall emissions, plastic pellet manufacturing accounts for most GHGs emitted in the plastic supply chain (Zhu et al., 2025). For studies without clearly defined boundaries, we assumed the reported emissions primarily reflected pellet production.

Glass recycling is the least effective at reducing emissions but still abates a meaningful amount at 79,000 t CO₂‑eq /Mt glass waste recycled (84,000 t CO₂‑eq /Mt glass waste recycled) (Table 1d). Emissions savings come from reduced fuel use in high-temperature melting furnaces and avoiding CO₂ release during the processing of raw materials (Baek et al., 2025).

While nitrous oxide is also released from fuel combustion during recycling of metals, paper and cardboard, plastics, and glass, it represents a small share of total CO₂‑eq emissions, so we considered it negligible (Diaz & Warith, 2006; U.S. EPA, 2016b).

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Table 1. Effectiveness at reducing emissions.

Unit: t CO₂‑eq /Mt metal waste recycled, 100-yr basis

25th percentile 1,410,000
Mean 1,480,000
Median (50th percentile) 1,480,000
75th percentile 1,550,000

Unit: t CO₂‑eq /Mt paper and cardboard waste recycled, 100-yr basis

25th percentile 600,000
Mean 1,000,000
Median (50th percentile) 1,000,000
75th percentile 2,000,000

Unit: t CO₂‑eq /Mt plastic waste recycled, 100-yr basis

25th percentile 2,000,000
Mean 2,000,000
Median (50th percentile) 2,000,000
75th percentile 2,000,000

Unit: t CO₂‑eq /Mt glass waste recycled, 100-yr basis

25th percentile 58,000
Mean 79,000
Median (50th percentile) 79,000
75th percentile 100,000
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Cost

Emissions mitigation from recycling metals and paper and cardboard results in net cost savings, while plastics break even and glass remains cost-intensive. Initial capital costs for all four material recycling systems are higher than for landfilling, but operating costs are lower. Net landfilling costs are overall profitable for all four materials (see Increase Centralized Composting and Improve Landfill Management for more information on landfilling costs). While operational costs for recycling can vary based on the design and efficiency of MRFs, overall savings can result from reduced landfill tipping fees, lower disposal volume, and revenue from selling recovered materials. These economic factors are determined by energy savings, market demand, and materials-specific recovery efficiencies.

Metals recycling generates net net savings of US$200 million/Mt metal waste recycled, or US$100/t CO₂‑eq mitigated (Table 2a). In addition to significantly reduced energy use and raw material costs (DebRoy & Elmer, 2024), metals recycling delivers high-quality materials comparable to newly mined metals (Damgaard et al., 2009). This drives strong market demand, with revenues often covering – and in some cases exceeding – the costs of separation and/or reprocessing alone.

Paper and cardboard recycling has the highest net savings of the four recycling streams compared to landfilling, with US$400 million/Mt paper and cardboard waste recycled. Combining effectiveness with the net costs presented here, we estimated a savings per unit climate impact of US$400/t CO₂‑eq (Table 2b). This reflects the energy and resource efficiency of paper recycling, along with revenue generation from recovered paper sales (Bajpai, 2014).

Plastics recycling costs US$8 million/Mt less than landfilling, yielding a cost saving of US$4/t CO₂‑eq (Table 2c). However, plastics recycling shows the most variability, ranging from modest savings to higher costs than primary material production. Inexpensive virgin plastics, high contamination risk, complex sorting and reprocessing, and weak or volatile market value (Li et al., 2022) make recycling plastics economically challenging without supportive policies or subsidies.

Glass recycling has a net cost of US$700 million/Mt glass waste recycled and the highest cost per unit of climate impact (US$9,000/t CO₂‑eq , Table 2d). This is due to high processing costs, low market value for cullet (e.g., selling for a fraction of the recycling cost; Figure A1), and contamination that limits resale or reuse (Bogner et al., 2007; Ng & Phan, 2021; Olafasakin et al., 2023). Although glass recycling is costly, the societal and environmental benefits are far higher than those of landfilling (Colangelo, 2024).

Financial data were geographically limited. We based cost estimates on global reports with selected studies from India, Saudi Arabia, the United Kingdom, and the United States for landfilling and Canada, the European Union, Germany, Philippines, and the United States for recycling. Transportation and collection of recyclables can add notable costs to waste management, but we did not include them in this analysis. We calculated amortized net cost for landfilling and recycling by subtracting revenues from operating costs and amortized initial costs over a 30-year facility lifetime. Furthermore, revenues reflect market-based prices, which are subject to change based primarily on demand for recyclables.

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Table 2. Cost per unit of climate impact.

Unit: 2023 US$/t CO₂‑eq , 100-yr basis

Median -100

Unit: 2023 US$/t CO₂‑eq , 100-yr basis

Median -400

Unit: 2023 US$/t CO₂‑eq , 100-yr basis

Median -4

Unit: 2023 US$/t CO₂‑eq , 100-yr basis

Median 9,000
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Learning Curve

We did not consider a learning curve for the Increase Recycling solution due to a lack of global data quantifying cost reductions specific to mechanical recycling technologies. Recycling systems use well-established processes that are already mature and widely deployed.

Recycling costs depend largely on regional factors, including material availability, market prices, infrastructure, and transportation distances. Consumer sorting habits and contamination rates also influence recycling performance and often outweigh potential learning-based cost decreases from technological improvements. Additionally, many mechanical recycling facilities operate near or at peak process efficiency, leaving little room for the technological upgrades that typically lower costs over time.

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Speed of Action

Speed of action refers to how quickly a climate solution physically affects the atmosphere after it is deployed. This is different from speed of deployment, which is the pace at which solutions are adopted.

At Project Drawdown, we define the speed of action for each climate solution as emergency brake, gradual, or delayed.

Increase Recycling is a GRADUAL climate solution. It has a steady, linear impact on the atmosphere.

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Caveats

Manufacturing emissions reductions due to recycling of metals, paper and cardboard, plastics, and glass are generally both permanent and additional, depending on local regulations and recycling practices. While recycling reduces the need for virgin production of raw materials and associated emissions, several caveats affect the extent of its climate benefits. 

Permanence

There is a low risk that the avoided emissions from increased recycling will be reversed in the next 100 years. Using recycled materials in place of newly extracted (virgin) resources avoids emissions from extraction, refining, and manufacturing. These reductions are considered permanent because the avoided activities occur to a lesser extent and fewer associated emissions are released. Recycling uses less energy and therefore reduces burning of fossil fuels and emits less GHGs. Avoided methane emissions from landfilled paper waste also has high permanence.

Additionality

Emissions reductions from increasing recycling are additional when improvements go beyond what would happen anyway under existing law or infrastructure. Increases in recycled rates, expansion to underdeveloped areas, and improvements in recycled material quality can result in additional climate benefits (Awino & Apitz, 2024; Halog & Anieke, 2021; Oo et al., 2024; Valenzuela-Levi et al., 2021). Efforts to enable or expand closed-loop recycling are also considered additional, especially for glass bottle recycling and in regions without this infrastructure.

Other Caveats

Material-specific limitations also apply. Material losses during product use and end-of-life processing limit metals recycling. Many metals are locked in products with long lifespans, difficult-to-separate designs, or technically unrecoverable applications, reducing availability for recycling (Ciacci et al., 2016; Guo et al., 2023). While improved recycling can decrease losses (Charpentier Poncelet et al., 2022), stagnant recycled metal inputs do not match growing metal demand (Watari et al., 2025).

Paper and cardboard can be recycled only five to seven times before fibers degrade beyond usability (Bajpai, 2014; Obradovic & Mishra, 2020), limiting long-term recyclability. Plastic recycling faces similar limits because many plastics degrade after a few cycles and mechanical processes are highly sensitive to contamination (Klotz et al., 2022; Klotz et al., 2023). For glass, downcycling is common due to quality control issues and variable regional demand for high-purity cullet. Van Ewijk et al. (2021) also emphasized that the benefits of paper recycling depend substantially on the carbon intensity of the energy used, highlighting the need to power recycling with low-carbon electricity.

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Current Adoption

Worldwide, we estimated that metals are recycled at a rate of 740 Mt/yr (Table 3a). We based this on a study by Gorman et al. (2022), which reported that approximately 1,277 Mt of metals were produced globally in 2018 using recycled feedstocks. This value included all types of scrap metals: postconsumer, pre-consumer, and home scrap reused within factories. To isolate postconsumer recycling, we applied a 58% share based on data from the U.S. Geological Survey (USGS, 2022), which gives a typical breakdown of scrap types across major metals. While this ratio is U.S.-based, we used it as a global proxy due to limited international data. Our current adoption estimate accounts for processing losses, contamination, and quality limits that prevent a full 1:1 replacement of virgin metals (Gorman et al., 2022).

We estimated current paper and cardboard recycling at 160 Mt/yr, the median among two global datasets and one report (United Nations Office on Drugs and Crime [UNODC], 2023; Table 3b). The most recent global data were compiled in 2023 by the Food and Agriculture Organization of the United Nations ([FAO], n.d.), and an earlier dataset from a World Bank analysis from 174 countries in 2018 (World Bank, 2018). To estimate postconsumer recycled paper, we assumed a 75% share of total paper waste based on industry averages (European Paper Recycling Council, 2024).

Plastics are currently recycled at a rate of 35.9 Mt/yr, based on one global dataset (173 countries; World Bank, 2018), two reports, and one study (Table 3c). Plastics Europe (2024a, 2024b) provides data on global mechanically recycled (postconsumer) plastics production, derived from estimations and statistical projections. We assumed the share of postconsumer plastics from Houssini et al. (2025) and World Bank (2018) to be 100% because the vast majority of plastic waste appears to originate from postconsumer sources.

Glass has the lowest current recycling rate at 27 Mt/yr, calculated as the midpoint among one global dataset (168 countries; World Bank, 2018), two reviews (Delbari & Hof, 2024; Ferdous et al., 2021), and one report (Maximize Market Research Private Limited, 2025) (Table 3d). For values based on total waste generation, we used a global production-based recycling rate, which may underestimate actual glass waste recycling due to limited data on postconsumer glass waste.

Since the World Bank (2018) provided data on waste generation in metric tons per year, we applied global recycling rates of 59.3%, 9%, and 21% to the total waste generated for paper and cardboard, plastics, and glass, respectively (see Appendix for details).

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Table 3. Current adoption level.

Unit: Mt recycled/yr, 2018

Estimate (Gorman et al., 2022) 740

Unit: Mt recycled/yr, 2023

25th percentile 150
Mean 160
Median (50th percentile) 160
75th percentile 180

Unit: Mt recycled/yr, 2023

25th percentile 31.2
Mean 32.0
Median (50th percentile) 35.9
75th percentile 36.6

Unit: Mt recycled/yr, 2020

25th percentile 24
Mean 24
Median (50th percentile) 27
75th percentile 27
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Adoption Trend

Postconsumer metals recycling has grown steadily in recent years (Table 4a, Figure 2). We used global data on secondary metals production from Gorman et al. (2022), a 39.1% share of recycled metals from the total addressable market (Gorman et al., 2022), and a 58% postconsumer scrap factor (USGS, 2022) to estimate the metals recycling adoption trend from 2014 to 2018. Annual adoption varies across this period. Taking the median annual change, we estimate a global adoption trend of 12 Mt/yr/yr, or 1.6% growth year-over-year (YoY). The mean annual change is estimated as 11 Mt/yr/yr, indicating consistent growth in the recovery of metals from end-of-life products.

Paper and cardboard recycling has gradually but inconsistently grown over the past two decades (Table 4b, Figure 2). Using worldwide recovered paper production data from the FAO (n.d.), we estimated the annual change in paper and cardboard waste recycled from 2003 to 2023. We applied a 75% factor to restrict this to postconsumer collection. While early years (2003–2016) in the data generally showed positive adoption, albeit with some fluctuations, more recent years (2017–2023) reflect declines, including noticeable drops in 2021–2022 (–1.9 Mt/yr/yr) and 2022–2023 (–5.4 Mt/yr/yr). The overall adoption trend is mixed despite a brief spike in 2020–2021. Taking the median annual change over the full 20-year period, we estimated a global trend of 2.2 Mt/yr/yr or a 1.3% YoY growth. The mean annual change is slightly higher at 2.8 Mt/yr/yr (2.0% YoY growth), indicating moderate but uneven progress in the recovery of paper and cardboard.

Plastics recycling is slowly increasing as a share of global plastic waste management, but the overall trend remains modest (Table 4c, Figure 2). We used data from the Organisation for Economic Co‑operation and Development ([OECD], 2022a) to estimate global adoption trends from 2000–2019 and supplemented this with 2019–2023 estimates from Plastics Europe (2022, 2023, 2024a). The adoption trend fluctuates from year to year, reflecting variability in collection rates, contamination levels, and recycling infrastructure. Taking the median annual change in recycled plastic waste across 23 years, we estimated a global adoption trend of 1.3 Mt/yr/yr, or 8.5% YoY growth. The mean annual change is slightly higher at 1.4 Mt/yr/yr, suggesting a slow growth in recycling capacity compared with plastic production volumes. However, this progress is uneven across geographies, with some countries expanding recycling systems while others face barriers, including limited infrastructure and low incentives for recovery.

Glass recycling showed a median annual change of 0 Mt/yr/yr and a mean of 0.8 Mt/yr/yr (3.7% growth YoY) from 2009–2019 (Table 4d, Figure 2). These estimates are based on Chen et al. (2020), who modeled World Bank data (Kaza et al., 2018) to generate a global dataset of waste treatment quantities across 217 countries. The apparent absence of change likely reflects limited availability of global data and inconsistent reporting rather than truly flat adoption. Although the dataset from Chen et al. (2020) is comprehensive, it is modeled rather than based on reported figures.

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Table 4. Adoption trend.

Unit: Mt/yr/yr, 2014–2018

25th percentile 2.3
Mean 11
Median (50th percentile) 12
75th percentile 20

Unit: Mt/yr/yr, 2003–2023

25th percentile 0.15
Mean 2.8
Median (50th percentile) 2.2
75th percentile 5.9

Unit: Mt/yr/yr, 2000–2023

25th percentile 0.93
Mean 1.4
Median (50th percentile) 1.3
75th percentile 1.8

Unit: Mt/yr/yr, 2009–2019

25th percentile 0
Mean 0.8
Median (50th percentile) 0
75th percentile 0
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Figure 2. Trends in recycling adoption of metals (2014–2018), paper & cardboard (2003–2023), plastics (2000–2023), and glass (2009–2019). Adapted from Chen et al. (2020), FAO (n.d.), Gorman et al. (2022), OECD (2022a), and Plastics Europe (2022, 2023, 2024a).

Sources: Chen, D. M.-C., Bodirsky, B. L., Krueger, T., Mishra, A., & Popp, A. (2020). The world’s growing municipal solid waste: Trends and impacts. Environmental Research Letters, 15(7), Article 074021; Food and Agriculture Organization of the United Nations. (n.d.). FAO‑FAOSTAT: Forestry production and trade [Data set]. Retrieved April 25, 2025; Gorman, M. R., Dzombak, D. A., & Frischmann, C. (2022). Potential global GHG emissions reduction from increased adoption of metals recycling. Resources, Conservation and Recycling, 184, Article 106424; Organisation for Economic Co‑operation and Development. (2022a). Global plastics outlook database [Data set]; Plastics Europe. (2022). Plastics – the facts 2022 [Report]; Plastics Europe. (2023). Plastics – the fast facts 2023 [Infographic]; Plastics Europe. (2024a). Plastics – the fast facts 2024 [Infographic].

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Adoption Ceiling

Metals recycling adoption is expected to remain high, with the global ceiling estimated at 2,100 Mt/yr (Table 5a). This corresponds to 68.2% of total projected metals production by 2050, based on the “maximum scenario” in Gorman et al. (2022). The scenario reflects a best-case technical potential of recycled metals adoption under full utilization of scrap feedstocks (Gorman et al., 2022). It assumes that all available postconsumer, pre-consumer, and home scrap can be recovered and can fully replace as much virgin material as possible using current technologies. We isolated the postconsumer portion as a 58% share of available metal scrap, as outlined in USGS (2022) data. 

There is also a strong potential for increased paper and cardboard recycling, with an estimated adoption ceiling of 360 Mt/yr (Table 5b). We assumed a recovery rate of 85% of total global paper production, accounting for practical limits imposed by fiber degradation, contamination, and processing inefficiencies. According to UNODC (2023), about 48% of paper globally is produced from recycled materials, leaving considerable room for improvement. The 85% ceiling also assumes that not all types of paper can be recovered (e.g., sanitary paper or heavily coated grades). Because this value is based on production rather than discarded paper waste, it may slightly underestimate the ceiling based on postconsumer waste generation. 

We estimated the adoption ceiling for plastics recycling at 180 Mt/yr (Table 5c). Technical barriers such as contamination, material heterogeneity, and plastic degradation constrain large-scale adoption. We therefore assumed and applied a 70% recycling rate to postconsumer plastic waste streams. We obtained similar estimates across multiple sources reporting global plastic waste generation (Houssini et al., 2025; OECD, 2022b; Stegmann et al., 2022). 

We estimated a ceiling of 100 Mt/yr for glass recycling (Table 5d) based on a 90% recovery rate from global waste generation estimates (Chen et al., 2020; Ferdous et al., 2021). Although glass is considered infinitely recyclable, losses due to contamination, sorting inefficiencies, and market constraints limit complete recovery. We included modeled estimates from Chen et al. (2020) to provide a more comprehensive global ceiling due to the scarcity of global data on glass recycling. 

For metals and paper and cardboard, values are derived from single datasets; for plastics, rounding across multiple datasets produced identical values across percentiles. Therefore, only the median is shown for these three subsolutions.

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Table 5. Adoption ceiling.

Unit: Mt recycled/yr

Estimate (Gorman et al., 2022) 2,100

Unit: Mt recycled/yr

Estimate (UNODC, 2023) 360

Unit: Mt recycled/yr

Median (50th percentile) 180

Unit: Mt recycled/yr

25th percentile 94
Mean 100
Median (50th percentile) 100
75th percentile 110
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Achievable Adoption

For sources reporting global recycling rates or tonnage for all materials except metals, we define low and high achievable adoption as 25% or 50% increase in the most recently available material-specific recycle rate, respectively.

For metals recycling, achievable adoption is largely shaped by the dynamics of secondary metal production in global commodity markets, which in turn depends on the relative quantity of scrap available (Ciacci et al., 2016). We set achievable adoption at 1,300–1,400 Mt/yr by 2050 (Table 6a), based on the “plausible” and “ambitious” scenarios from Gorman et al. (2022), respectively. These estimates represent 41–48% of projected global metals production and incorporate both postconsumer and pre-consumer scrap, with the postconsumer share standardized at 58% across scenarios (USGS, 2022). Major commodity metals included in these estimates are steel, aluminum, copper, zinc, lead, iron, nickel, and manganese, which together represent more than 99% of all metal demand by mass from 2014–2018 (USGS, 2021). Material availability and infrastructure for downstream scrap processing remain key hurdles (Allwood et al., 2025), although industrial-scale recovery systems are already well established in many high-income countries (Campbell et al., 2022; de Sa & Korinek, 2021).

We estimated the achievable adoption range for paper and cardboard recycling at 220–260 Mt/yr (Table 6b), with an assumed postconsumer share of 75% applied to the total global recycling volumes reported by FAO (n.d.) and UNODC (2023). This range reflects expanded municipal collection, improvements in fiber separation technologies, and increased demand for recovered pulp in paper manufacturing. 

Plastics recycling has substantial opportunity for growth, given <10% global recycling rates and the exponential growth of plastic accumulation in the environment (Dokl et al., 2024; Nayanathara Thathsarani Pilapitiya & Ratnayake, 2024). A 25–50% increase in global mechanically recycled plastic volumes would bring the achievable range to 45–54 Mt/yr (Table 6c). While meaningful, these levels are 8–9 times smaller than the 414 Mt of plastic produced in 2023 (Plastics Europe, 2024a). Constraints include the complexity of sorting mixed plastic streams, limited market demand for lower-grade recycled pellets, and insufficient investment in complementary technologies such as chemical recycling, which remains below 0.5 Mt/yr.

For glass recycling, we set an achievable adoption range of 36–48 Mt/yr by 2050 (Table 6d), based on harmonized waste modeling and forward-looking estimates from Chen et al. (2020) and Delbari and Hof (2024). However, this scale-up depends substantially on reducing contamination at the collection stage, expanding color- and ceramic-sorting technologies, and improving closed-loop markets for container glass (Baek et al., 2025; Yuan et al., 2024).

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Table 6. Range of achievable adoption.

Unit: Mt recycled/yr

Current adoption 740
Achievable – low 1300
Achievable – high 1400
Adoption ceiling 2100

Unit: Mt recycled/yr

Current adoption 160
Achievable – low 220
Achievable – high 260
Adoption ceiling 360

Unit: Mt recycled/yr

Current adoption 36
Achievable – low 45
Achievable – high 54
Adoption ceiling 180

Unit: Mt recycled/yr

Current adoption 27
Achievable – low 36
Achievable – high 48
Adoption ceiling 100
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Increased recycling has strong potential for climate impact, especially in reducing emissions from virgin material production and landfilling waste (see Appendix for waste sector emissions). 

Metals recycling has the highest current and achievable GHG emissions savings of the four material categories (Table 7a). At a >500 Mt/yr current adoption rate, we estimate current metals recycling avoids 1.1 Gt CO₂‑eq/yr (1.2 Gt CO₂‑eq/yr, 20-year basis). Our low and high achievable adoption levels reduce 1.9 and 2.1 Gt CO₂‑eq/yr (2.1 and 2.4 Gt CO₂‑eq/yr, 20-year basis), respectively, with annual GHG reductions up to 3.1 Gt CO₂‑eq/yr (3.5 Gt CO₂‑eq/yr, 20-year basis) using the adoption ceiling. 

Paper and cardboard recycling currently avoids 0.16 Gt CO₂‑eq/yr (0.16 Gt CO₂‑eq/yr, 20-year basis) (Table 7b). Achievable GHG reduction is 0.22–0.26 Gt CO₂‑eq/yr (0.22–0.26 Gt CO₂‑eq/yr, 20-year basis), with a maximum potential of 0.36 Gt CO₂‑eq/yr (0.36 Gt CO₂‑eq/yr, 20-year basis).

Plastics recycling has a lower current climate impact of 0.07 Gt CO₂‑eq/yr (0.1 Gt CO₂‑eq/yr, 20-year basis), but it has the potential to increase to a ceiling matching that of recycling paper and cardboard (Table 7c). We estimated low and high achievable adoption levels avoid 0.09 and 0.1 Gt CO₂‑eq/yr (0.1 and 0.2 Gt CO₂‑eq/yr, 20-year basis), respectively, with GHG emissions savings of 0.4 Gt CO₂‑eq/yr (0.5 Gt CO₂‑eq/yr, 20-year basis) at the adoption ceiling. The 20-year impacts highlight the mitigated methane emissions associated with oil refining for virgin plastic production, with recycling plastics reducing both the need for petrochemical feedstocks and the volume of waste sent to landfills.

Glass recycling has the lowest current and achievable emissions reductions, avoiding 0.0021 Gt CO₂‑eq/yr (0.0023 Gt CO₂‑eq/yr, 20-year basis) with the potential to increase to 0.0028–0.0038 Gt CO₂‑eq/yr (0.0030–0.0041 Gt CO₂‑eq/yr, 20-year basis) under higher adoption (Table 7d). We estimated a maximum impact ceiling of 0.0079 Gt CO₂‑eq/yr (0.0084 Gt CO₂‑eq/yr, 20-year basis). Although emissions savings are relatively small, glass recycling is still worthwhile to benefit from cullet-driven energy reductions, conserve raw materials, and contribute to larger reductions when combined with other materials in municipal recycling programs.

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Table 7. Climate impact at different levels of adoption.

Unit: Gt CO₂‑eq/yr, 100-year basis

Current adoption 1.1
Achievable – low 1.9
Achievable – high 2.1
Adoption ceiling 3.1

Unit: Gt CO₂‑eq/yr, 100-year basis

Current adoption 0.16
Achievable – low 0.22
Achievable – high 0.26
Adoption ceiling 0.36

Unit: Gt CO₂‑eq/yr, 100-year basis

Current adoption 0.07
Achievable – low 0.09
Achievable – high 0.1
Adoption ceiling 0.4

Unit: Gt CO₂‑eq/yr, 100-year basis

Current adoption 0.0021
Achievable – low 0.0028
Achievable – high 0.0038
Adoption ceiling 0.0079
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In our analysis, we adjusted emissions reductions from recycling using a TSR, since recycled materials often do not replace virgin materials on a 1:1 basis due to differences in quality, durability, or performance (Nordahl & Scown, 2024). To ensure we didn’t overestimate emissions savings, we applied an average material-specific ratio that adjusted the avoided emissions from primary material production. Recycled paper and cardboard and glass were assigned a ratio of 0.83; metals, 0.90; and plastics, 0.80 (Figure 3). These unitless ratios were based on technical literature (Barbato et al., 2024; Rigamonti et al., 2020; UNEP, 2024; Zheng & Suh, 2019) and were applied consistently across all emissions units for effectiveness.

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Figure 3. Conceptual diagram of a general recycling loop for (a) metals, (b) paper & cardboard, (c) plastics, and (d) glass and how technical substitutability determines the maximum share of recycled content due to quality constraints. Graphics for (b), including the MRF and manufacturing plant for (a), (c), and (d), were modified from International Paper (n.d.). BioRender and Canva were used to make the remaining graphics.

Recycling cycle diagram.

Source: International Paper. (n.d.). Paper’s life cycle: The recycling process [Infographic]. Retrieved June 10, 2025.

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Additional Benefits

Income and Work

Recycling can create jobs and reduce energy costs. The National Institutes of Health (NIH) estimated that incinerating or landfilling 10 kt of waste creates one or six jobs respectively, while recycling the same amount of waste creates 36 jobs (NIH Environmental Management System [NEMS], n.d.). A case study in Florida found that increasing recycling rates can lead to small amounts of job growth, with most new jobs concentrated in the recycling processing sector (Liu et al., 2020). 

Using recycled materials can reduce the need for imports and support domestic manufacturing (Das et al., 2010; Dussaux & Glachant, 2019). The sale of products manufactured from recyclables instead of virgin materials can translate to economic benefits. A study of recycling systems in Nigeria found that the sale of recyclables could contribute about US$11.7 million to the country’s economy each year and create about 16,562 new jobs (Ayodele et al., 2018).  

Health

Materials in landfills can leach into the surrounding environment (McGinty, 2021). Plastics, along with associated additives such as bisphenol A and phthalates, can degrade into microplastics that enter the surrounding ecosystem and food chain, posing health risks to humans (Bauer et al., 2022; Li et al., 2022; Rajmohan et al., 2019; Zheng & Suh, 2019).

Equality

In low- and middle-income countries, informal recycling, which involves networks of individuals who sort through waste and sell or recycle it using informal methods, is a common form of waste management (Yang et al., 2018). Increasing recycling in these contexts could formalize this recycling method and improve some of the social and health equity concerns associated with informal recycling, such as exploitation, safety, child labor, and occupational health exposures, and may improve income-earning capabilities (Aparcana & Salhofer, 2013; Yang et al., 2018). Low- and middle-income countries typically face a disproportionate burden of plastic pollution, which could be improved by increasing recycling capacities globally (World Wildlife Fund [WWF], 2023). 

Land Resources

Recycling can benefit land resources and soil quality by reducing materials in landfills and incinerators and by reducing the need to extract virgin materials such as timber and minerals (Dussaux & Glachant, 2019; McGinty, 2021; U.S. EPA, 2025). Rajmohan et al. (2019) estimated that about 22–43% of plastic waste reaches landfills. Plastic waste can degrade into microplastics, leaching into surrounding ecosystems and reducing soil fertility (McGinty, 2021; Rajmohan et al., 2019). The environmental benefits of displacing the need for production using virgin materials through recycling may be more significant than reducing landfilling (Geyer et al., 2016). Recycling, along with the use of wood residues, is projected to reduce the demand for wood and fiber, easing pressures on land resources (FAO, 2009). 

Water Resources

Recycling can reduce the amount of water needed to produce new materials. For example, using recycled steel to make steel requires 40% less water than using virgin materials (NEMS, n.d.).

Air Quality

Increasing recycling reduces the amount of waste in landfills and incinerators and can reduce harmful pollution associated with landfilling and incineration (U.S. EPA, 2025). Additionally, recycling reduces the need to mine and process new materials, thereby reducing air pollution emitted during these processes (U.S. EPA, 2025).

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Risks

Increasing metals recycling, paper and cardboard recycling, and plastics recycling can inadvertently increase environmental and human exposure to hazardous chemicals if not properly managed. Exposure to heavy metal fumes can occur while processing metal waste, and concealed pressurized or reactive items in scrap can cause fires or explosions. Chemical additives such as mineral oils and printing inks often persist throughout the paper life cycle and can migrate into the environment and food packaging, posing health risks such as chronic inflammation, endocrine disruption, and cancer (Pivnenko et al., 2016; Sobhani & Palanisami, 2025). Flame retardants, per- and polyfluoroalkyl substances, and other pollutants can leach from materials during and after plastics recycling. Microplastics accumulate at higher concentrations in recycled plastics and are released during all recycling stages (Monclús et al., 2025; Singh & Walker, 2024). Additionally, recycled papers and plastics contain unintentionally added substances, which carry different additives whose composition is often unknown (Monclús et al., 2025; Sobhani & Palanisami, 2025).

Increased plastics collection for recycling without global coordination can lead to disproportionate plastic pollution if high-income countries export plastic waste to low-income countries with inadequate recycling infrastructure (Singh & Walker, 2024).

When glass recycling is included in single-stream systems, glass shards can damage MRF machinery and contaminate other recyclable materials, decreasing their market value (Deer, 2021). Additionally, the heavy weight and fragility of glass means recycling trucks require multiple trips, consuming more fuel and increasing transportation costs. 

Another key risk is that materials collected for recycling may ultimately be landfilled when poor market conditions prevent their recovery. 

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Interactions with Other Solutions

Reinforcing

All of these solutions can reuse clean and high-quality recycled materials as a raw material or feedstock or repurpose them as substitute materials in targeted uses. The embodied emissions from the recovered waste used as production or process inputs will be reduced, enhancing the solutions’ net climate impacts and supporting circularity.

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Recycling paper and cardboard waste reduces deforestation required for extracting and processing primary raw materials.

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Increased adoption of efficient mechanical recycling systems and equipment can improve the rate and cost of scaling similar highly-efficient, complementary technologies (e.g., chemical recycling). 

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Competing

Diverting certain paper and cardboard types from landfills lowers methane emissions available to be captured and sold for biogas revenue. Paper and cardboard recycling also can reduce the amount of material that can be converted into biochar or compost.

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Dashboard

Solution Basics

Mt recycled

t CO₂-eq (100-yr)/unit
01.41×10⁶1.48×10⁶
units/yr
Current 740 01,3001,400
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 1.1 1.92.1
US$ per t CO₂-eq
-100
Gradual

CO₂ , CH₄

Solution Basics

Mt recycled

t CO₂-eq (100-yr)/unit
0600,0001.0×10⁶
units/yr
Current 160 0220260
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 0.16 0.220.26
US$ per t CO₂-eq
-400
Gradual

CO₂ , CH₄

Solution Basics

Mt recycled

t CO₂-eq (100-yr)/unit
2.0×10⁶
units/yr
Current 35.9 04554
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 0.07 0.090.1
US$ per t CO₂-eq
-4
Gradual

CO₂ , CH₄

Solution Basics

Mt recycled

t CO₂-eq (100-yr)/unit
058,00079,000
units/yr
Current 27 03648
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 0.002 0.0030.004
US$ per t CO₂-eq
9,000
Gradual

CO₂ , CH₄

Trade-offs

Ciacci et al. (2016) and van Ewijk and Stegemann (2023) noted that as recycling approaches near-total recovery, energy consumption steeply rises, driven by increased decontamination efforts, sorting challenges, and diminished material quality. However, recycling rates are currently low enough that recycling is less carbon intense than primary material manufacturing.

The eventual quality degradation in secondary materials requires supplementation with virgin resources. However, overall embodied emissions are still lower than they would be for producing all-new materials. 

Glass recycling poses a trade-off between convenience and recycling efficiency in single-stream systems. Only 40% of glass is repurposed into new products, and the glass can contaminate other materials. Multi-stream or source-separated systems require more effort but achieve 90%-plus recycling rates (Berardocco et al., 2022; Deer, 2021).

Watari et al. (2025) noted that countries can achieve high local recycling rates and high recycled content by importing scrap metals from elsewhere, but with the trade-off that metal production emissions are offshored rather than reduced. This also introduces dependencies on international scrap flows and global supply chains (Guo et al., 2023), which can similarly occur for paper, cardboard, and plastics.

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Action Word
Increase
Solution Title
Recycling
Classification
Highly Recommended
Lawmakers and Policymakers
  • Establish ambitious recycling goals; incorporate them into climate plans.
  • Ensure public procurement uses recycled materials or products as much as possible.
  • Consult with manufacturers, retailers, and the public to determine how best to design local recycling programs.
  • Empower citizen leaders to help manage MSW collection and recycling programs; ensure legal and regulatory structures clearly designate citizen and/or local control to avoid political disagreements and interference.
  • Use decision-making models and economic analysis tools to design MSW systems that incorporate aspects such as life-cycle assessments, material flows, cost/benefit analyses, environmental impact assessments, management systems, and assessments of immediate impacts on human well-being, especially in low-income and urban settings.
  • Ensure waste management systems and practices are appropriate for the local context and not just imported models from other countries.
  • Coordinate recycling efforts, policies, and budgets horizontally (e.g., across agencies) and vertically (e.g., across subnational, national, and international efforts), ensuring an inclusive process for local communities.
  • Use financial incentives that are appropriate for the local context such as subsidizing recycling plants, transportation, and pickup; offer tax exemptions and other incentives to low-income communities.
  • Use financial disincentives and taxes appropriate for the local context, such as landfilling fees, rent and/or property taxes, product fees, and collection fees included in utility bills or tied to waste quantity; ensure fees do not burden or stop low-income communities from recycling (possibly by tying collection fees to income bracket).
  • Invest in waste management infrastructure, including waste drop-off and buy-back centers, collection and separation facilities, roads and collection vehicles, education programs, community engagement mechanisms, and research and development for more efficient recycling techniques, behavioral change mechanisms, product design, and alternative materials.
  • Institute bans on landfilling recyclable (or compostable) materials; establish penalties for noncompliance.
  • Enact container deposit programs to encourage recycling and reuse.
  • Mandate standard shapes and color coding for waste bins to facilitate collection and separation.
  • Ban single-use plastics such as shopping bags and water bottles; ensure strong customs enforcement for imports.
  • Enact extended producer responsibility approaches that hold producers accountable for waste; set standards for the traceability of materials; require clear labeling for recyclable products.
  • Aim to eliminate government corruption behind illicit waste trade; create monitoring programs to hold waste managers accountable.
  • Incentivize or encourage waste management facilities to run on renewable energy and use electric fleets.
  • Incentivize or encourage manufacturers – including climate solution industries such as solar and wind producers – to use as much recycled materials as possible.
  • Require products made of metal, paper, plastic, or glass to contain a minimum percentage of recycled materials; ensure packaging producers meet recycling obligations potentially through the use of market-based mechanisms such as packaging waste recovery notes (PRNs) and/or packaging waste export recovery notes (PERNs).
  • Work to bring informal waste pickers into the formal MSW system by providing or advocating for training, protective gear, formal employment, free or low-cost childcare services, and other social benefits and purchasing separated recyclable waste.
  • Work with businesses and industries to develop consistent markets for recycled goods and stabilize the price of recycled materials.
  • Carefully enter into transparent public–private recycling partnerships, ensuring legal systems can enforce compliance with contractual terms.
  • Set collection fees, designate collection areas, and establish the amount of monitoring services at the municipal level rather than letting private companies do so.
  • Improve building codes and manufacturing regulations to require the use of recycled materials and material traceability; set standards for building and vehicle demolition to require the recovery of window glass and other recyclable materials.
  • Set recycling-facilitating regulations and standards for product disassembly.
  • Set standards that ease barriers for trading recycled goods and recyclable materials; halt the export of waste from rich countries to low- and middle-income countries; enforce trade standards and ensure illicit trade networks do not circumvent them.
  • Foster cooperation and technology transfers between low- and middle-income countries, avoiding models used in rich countries that are ill-suited for other contexts.
  • Deploy diverse means of engaging the public in recycling, such as volunteer groups, social activities, and musical trucks.
  • Create or improve training programs for waste management professionals that focus on practical skills and knowledge for working with communities to design and manage MSW systems.
  • Partner with schools, manufacturers, retailers, nonprofits, and other community organizations to promote recycling.
  • Establish programs that teach how to separate waste effectively, the waste hierarchy, and why these processes are important; incorporate these concepts into public school curricula.

Further information:

Practitioners
  • Place recycling plants as close to points of waste generation as possible.
  • Consult with government officials, manufacturers, retailers, and the public to determine how best to design local recycling programs; utilize local data to inform planning, development, collection, and sorting techniques.
  • Support and cooperate with citizen leaders to help manage MSW collection and recycling programs.
  • Use decision-making models and economic analysis tools to design MSW systems that incorporate aspects such as life-cycle assessments, material flows, cost/benefit analyses, environmental impact assessments, management systems, and assessments of immediate impacts on human well-being, especially in low-income and urban settings.
  • Take advantage of financial incentives such as subsidies for recycling plant construction, transportation, and pickup; if none exist, advocate to policymakers for incentives.
  • Invest in waste management infrastructure, including waste drop-off and buy-back centers, collection and separation facilities, roads, collection vehicles, education programs, community engagement mechanisms, and research and development for more efficient recycling techniques, behavioral change mechanisms, product design, and alternatives to non-recyclable materials.
  • Use energy efficiency equipment and enhanced heat recovery techniques; install smart technology control systems.
  • Use electric equipment and renewable energy sources as much as possible.
  • Work with the renewable energy industry to ensure new solar photovoltaic panels and wind turbines utilize as much recycled materials as possible.
  • Work to bring informal waste pickers into the formal MSW system by providing or advocating for training, protective gear, formal employment, free or low-cost childcare services, and other social benefits and purchasing separated recyclable waste.
  • Work with policymakers, businesses, and industries to develop consistent markets for recycled goods and stabilize the price of recycled materials.
  • Deploy diverse means of engaging the public in recycling, such as volunteer groups, social activities, and musical trucks.
  • Create or improve training programs for waste management professionals that focus on practical skills and knowledge for working with communities to design and manage MSW systems.
  • Partner with schools, manufacturers, retailers, nonprofits, and other community organizations to promote recycling.
  • Establish programs that teach how to separate waste effectively, the waste hierarchy, and why these processes are important; incorporate these concepts into public school curricula.

Further information:

Business Leaders
  • Use recycled materials in business operations as much as possible and ensure employees recycle.
  • Improve the quality of products, reduce material usage and product weight, and extend product life cycles through design that allows for easy reuse, repair, upgrading, recycling, and remanufacturing.
  • Work with industry peers to set design standards for common products that contain recycled materials.
  • Improve the traceability of materials used in products to enhance sorting efficiency.
  • Collect used products and reuse the materials for future production.
  • Advocate to policymakers for improved municipal recycling programs and support for integrating recycled products into your industry.
  • Provide financial assistance to employees for training in sustainable waste management, circular business models, and other related fields.
  • Create or join platforms that allow business-to-business collaboration to increase adoption of recycling and integration of recycled materials into products and business models.
  • Conduct market research on consumer demands and trends to identify potential markets for recycled materials.
  • Fund research or start-ups that aim to boost recycling in your industry.
  • Create, support, or join education campaigns and/or public-private partnerships that facilitate collaboration on recycling.

Further information:

Nonprofit Leaders
  • Ensure procurement uses strategies to reduce waste and use recycled materials as much as possible.
  • Help administer local recycling programs; take advantage of financial incentives such as subsidies for recycling plants, transportation, and pickup; ensure services are provided to low-income communities.
  • Consult with government officials, manufacturers, retailers, and the public to determine how best to design local recycling programs.
  • Help recycling service providers navigate certification and permitting; help identify funding opportunities.
  • Help develop decision-making models and economic analyses for designing recycling systems, incorporating aspects such as life-cycle assessments, material flows, cost/benefit analyses, environmental impact assessments, management systems, and assessments of impacts on human well-being, especially in low-income and urban settings.
  • Improve data collection on employment figures in the waste and recycling sectors; work to capture labor statistics for informal waste pickers – especially, women and children involved in the sector that are not captured by current data.
  • Advocate for ambitious public recycling goals, including integration into local and national climate plans.
  • Advocate for international trade standards that ease barriers for trading in recycled goods and recyclable materials; seek to halt the practice of rich countries exporting waste to low- and middle-income countries; advocate for better enforcement of trade standards to ensure illicit trade networks do not circumvent these standards.
  • Create or improve training programs for waste management professionals that focus on practical skills and knowledge for working with communities to design and manage MSW systems.
  • Advocate for bans on discarding recyclable materials to landfills and penalties for noncompliance.
  • Establish or advocate for container deposit programs to encourage recycling and reuse.
  • Advocate for bans on single use plastics such as shopping bags and water bottles.
  • Advocate for extended producer responsibility approaches that hold producers accountable for waste; demand standards for traceability and labeling of materials in products to facilitate recycling.
  • Empower citizen leaders to help manage MSW collection and recycling programs; advocate for clear legal and regulatory structures to avoid political disagreements and interference.
  • Help safeguard against government corruption to avoid the illicit waste trade; create monitoring programs to hold waste management companies and/or leadership accountable.
  • Deploy diverse means of engaging the public in recycling, such as volunteer groups, social activities, and musical trucks.
  • Work to bring informal waste pickers into the formal MSW system by providing or advocating for training, protective gear, formal employment, free or low-cost childcare services, and other social benefits.
  • Help facilitate local cooperatives or other management structures for recycling programs; offer to purchase separated recyclable waste from waste pickers.
  • Work with businesses and industry to develop consistent markets for recycled goods and stabilize the price of recycled materials.
  • Partner with schools, manufacturers, retailers, nonprofits, and other community organizations to promote recycling.
  • Establish programs that teach how to separate waste effectively, the waste hierarchy, and why these processes are important; incorporate these concepts into public school curricula.
  • Create, support, or join education campaigns and/or public-private partnerships that facilitate collaboration on recycling.

Further information:

Investors
  • Ensure portfolio companies and company procurement reduce waste, recycle, and use recycled materials at all stages of the supply chain.
  • Require portfolio companies to measure and report on waste, recycling rates, and use of recycled materials.
  • Provide low-interest loans to recycling service providers for start-up capital, improving efficiency, transitioning to renewable energy, and other development needs.
  • Invest in companies developing or modifying products to be compatible with a circular economy.
  • Fund start-ups that aim to improve sorting technologies, alternative packaging materials, energy efficiency of waste separation equipment, and other industry needs.
  • Offer financial services, notably rural financial market development, including low-interest loans, microfinancing, and grants, to support recycling initiatives.
  • Create, support, or join education campaigns and/or public-private partnerships that facilitate collaboration on recycling.

Further information:

Philanthropists and International Aid Agencies
  • Ensure your organization’s procurement recycles and uses recycled materials as much as possible.
  • Help administer local recycling programs; take advantage of financial incentives such as subsidies for recycling plants, transportation, and pickup; ensure services are provided to low-income communities.
  • Foster cooperation and technology transfers between low- and middle-income countries, avoiding models used in rich countries that are ill-suited for other contexts.
  • Offer grants and loans to establish recycling projects, ensuring projects have sustainable means of generating income sources to maintain operations after grant or loan terms end.
  • Provide low-interest loans to recycling service providers for start-up capital, improving efficiency, transitioning to renewable energy, and other development needs.
  • Invest in companies developing or modifying products to be compatible with a circular economy.
  • Fund start-ups that aim to improve sorting technologies, alternative packaging materials, energy efficiency of waste separation equipment, and other industry needs.
  • Offer financial services, notably rural financial market development, including low-interest loans, microfinancing, and grants to support recycling initiatives.
  • Hold community consultations with government officials, manufacturers, retailers, and the public to determine how best to design local recycling programs.
  • Help recycling service providers navigate certification and permitting processes.
  • Help develop decision-making models and economic analyses for designing recycling systems, incorporating aspects such as life-cycle assessments, material flows, cost/benefit analyses, environmental impact assessments, management systems, and assessments of impacts on human well-being, especially in low-income and urban settings.
  • Improve data collection on employment figures in the waste and recycling sectors; work to capture labor statistics for informal waste pickers – especially, women and children involved in the sector that are not captured by current data.
  • Advocate for ambitious public recycling goals and for the goals to be integrated into local and national climate plans.
  • Advocate for international trade standards that ease barriers for trading in recycled goods and recyclable materials; seek to halt the practice of rich countries exporting waste to low- and middle-income countries; advocate for better enforcement of trade standards to ensure illicit trade networks do not circumvent these standards.
  • Create or improve training programs for waste management professionals that focus on practical skills and knowledge for working with communities to design and manage MSW systems.
  • Advocate for bans on discarding recyclable (or compostable) materials to landfills and penalties for noncompliance.
  • Establish or advocate for container deposit programs to encourage recycling and reuse.
  • Advocate for bans on single use plastics such as shopping bags and water bottles.
  • Advocate for extended producer responsibility approaches that hold producers accountable for waste; demand standards for the traceability and labeling of materials in products to facilitate the recycling process.
  • Empower citizen leaders to help manage MSW collection and recycling programs; advocate for clear legal and regulatory structures to avoid political disagreements and interference.
  • Help safeguard against government corruption to avoid the illicit waste trade; create monitoring programs to hold waste management companies and/or leadership accountable.
  • Deploy diverse means of engaging the public in recycling, such as volunteer groups, social activities, and musical trucks.
  • Work to bring informal waste pickers into the formal MSW system by providing or advocating for training, protective gear, formal employment, free or low-cost childcare services, and other social benefits.
  • Help facilitate local cooperatives or other management structures for recycling programs; offer to purchase separated recyclable waste from waste pickers.
  • Work with businesses and industry to develop consistent markets for recycled goods and to stabilize the price of recycled materials.
  • Partner with schools, manufacturers, retailers, nonprofits, and other community organizations to promote recycling.
  • Establish programs that teach how to separate waste effectively, the waste hierarchy, and why these processes are important; incorporate these concepts into public school curricula.
  • Create, support, or join education campaigns and/or public-private partnerships that facilitate collaboration on recycling.

Further information:

Thought Leaders
  • Adopt recycling, share your experience, and inform your community how to effectively recycle in your area.
  • Consult with government officials, manufacturers, retailers, and the public to determine how best to design local recycling programs.
  • Help recyclers navigate certification and permitting; help identify funding opportunities.
  • Help develop decision-making models and economic analyses for designing recycling systems, incorporating aspects such as life-cycle assessments, material flows, cost/benefit analyses, environmental impact assessments, management systems, and assessments of impacts on human well-being, especially in low-income and urban settings.
  • Create ways of tracing materials and verifying recycled materials; explore the use of blockchain technology.
  • Conduct climate impact assessments of chemical recycling for plastics at an industrial scale; assess its feasibility to supplement mechanical recycling.
  • Improve data collection on employment figures in the waste and recycling sectors; work to capture labor statistics for informal waste pickers – especially, women and children involved in the sector that are not captured by current data.
  • Research and develop strategies for increasing recycling behavior.
  • Advocate for ambitious public recycling goals and for the goals to be integrated into local or national climate plans.
  • Advocate for international trade standards that ease barriers for trading in recycled goods and recyclable materials; seek to halt the practice of rich countries exporting waste to low- and middle-income countries (“waste dumping”); advocate for better enforcement of trade standards to ensure illicit trade networks do not circumvent these standards.
  • Create or improve training programs for waste management professionals that go into practical skills and knowledge for working with communities to design and manage MSW systems.
  • Advocate for bans on discarding recyclable (or compostable) materials to landfills and penalties for noncompliance.
  • Advocate for container deposit programs to encourage recycling and reuse.
  • Advocate for bans on single use plastics such as shopping bags and water bottles.
  • Advocate for extended producer responsibility approaches that hold producers accountable for waste; demand standards for the traceability and labeling of materials in products to facilitate the recycling process.
  • Empower citizen leadership to help manage MSW collection and recycling programs; advocate for clear legal and regulatory structures to avoid political disagreements and interference.
  • Help safeguard against government corruption to avoid the illicit waste trade; create monitoring programs to hold waste management companies and/or leadership accountable.
  • Deploy diverse means of engaging the public in recycling, such as volunteer groups, social activities, and musical trucks.
  • Work with businesses and industry to develop consistent markets for recycled goods and to stabilize the price of recycled materials.
  • Partner with schools, manufacturers, retailers, nonprofits, and other community organizations to promote recycling.
  • Establish programs that teach how to separate waste effectively, the waste hierarchy, and why these processes are important; incorporate these concepts into public school curricula.
  • Create, support, or join education campaigns and/or public-private partnerships that facilitate collaboration on recycling.

Further information:

Technologists and Researchers
  • Improve the efficiency of waste separation machinery and develop low-cost, low-maintenance means of waste management – particularly for contexts such as low- and middle-income countries.
  • Improve collecting, sorting, and pre-treating processes to enhance recovery of materials while minimizing degradation and contamination.
  • Improve energy efficiency of equipment such as glass furnaces by enhancing heat recovery; design or improve smart technology control systems.
  • Explore the use of artificial intelligence in separating waste streams.
  • Explore, discover, or improve new uses for recycled or recovered materials.
  • Create ways of tracing materials and verifying recycled materials, such as blockchain technology.
  • Engineer means of reducing the weight of materials in common products such as packaging and glass without sacrificing recyclability or functionality.
  • Improve chemical recycling of plastics – particularly solvent-based purification and de-polymerization – while maintaining low energy consumption and high utilization rates for the remaining waste.
  • Assess the climate impact of industrial-scale chemical recycling of plastics and its feasibility to supplement mechanical recycling.
  • Advance systems for collecting, sorting, and recycling metals, plastics, and glass contained in electronic devices.
  • Improve means of removing ink and adhesives from paper.
  • Improve waste handling techniques and environmental safeguards for the sludge produced during paper recycling; design products using the sludge.
  • Enhance systems for sorting plastics.
  • Research ways to improve recycling or reusing agricultural, construction, and thermoset plastics; find means to recycle polymers such as PVC.
  • Increase the performance of metal-sensing and -sorting equipment such as X-ray detection or spectroscopy; improve means of detecting external impurities, especially in steel scrap.
  • Design recycle-friendly alloys that can be used in a variety of ways and products.
  • Improve technology for sorting colored glass and detecting ceramics.
  • Improve liquefaction technology for plastics to reduce costs, minimize upgrading needs, and produce higher quality products.
  • Research and develop strategies for increasing recycling behavior.
  • Collect up-to-date data on recycled materials - particularly, on glass recycling. 

Further information:

Communities, Households, and Individuals
  • Participate in local recycling programs, share your experience with your community, and educate others on how to recycle in your area.
  • Practice conscious consumerism; buy only what’s needed and avoid products that use excessive packaging or have a short lifespan.
  • Form stakeholder groups to monitor and help administer local recycling systems.
  • Reuse products, packaging, and materials as much as possible before recycling or disposing of them.
  • Use your power as a consumer to influence businesses to adopt practices that increase recycling.
  • Participate in or advocate for consultations with government officials, manufacturers, retailers, and the public to determine how best to design local recycling programs.
  • Advocate for ambitious public recycling goals to be integrated into local or national climate plans.
  • Advocate for bans on discarding recyclable materials to landfills and penalties for noncompliance.
  • Establish or advocate for container deposit programs to encourage recycling and reuse.
  • Advocate for bans on single use plastics such as shopping bags and water bottles.
  • Advocate for extended producer responsibility approaches that hold producers accountable for waste; demand standards for the traceability and labeling of materials in products to facilitate recycling.
  • Help safeguard against government corruption to avoid the illicit waste trade; create community monitoring programs to hold waste management companies and/or leaders accountable.
  • Create, support, or join education campaigns and/or public-private partnerships that facilitate collaboration on recycling.

Further information:

Sources
Evidence Base

Consensus of effectiveness of recycling as a climate solution: High 

Recycling reduces solid waste, mitigates GHG emissions from landfilled solid waste, and offers significant savings in electricity and fuel consumption (Cudjoe et al., 2021; Kaza et al., 2018; Uekert et al., 2023). UNEP (2024) estimated that 2.1 Gt of municipal solid waste was generated globally in 2020, and projected that to increase to 3.8 Gt by 2050 if action is not taken. Although postconsumer waste contributes ~5% to total global GHG emissions (Oo et al., 2024), around 30–37% of global waste ends up in landfills with only 19% recovered through recycling and composting processes (Kaza et al., 2018; UNEP, 2024).

Three extensive reviews of industrial decarbonization identify four technologies either ready for near-term deployment or already achieving material impact across global industries: electrification, material efficiency, energy efficiency, and circularity driven by increased reuse and recycling (Daehn et al., 2022; Gailani et al., 2024; Rissman et al., 2020). The last includes recovery of the four waste subcategories considered in this solution, where metals and plastics rank among the top six most-produced human-made materials globally (BioCubes, n.d.).

Incorporating recycled metal scraps into manufacturing consumes 30–95% less energy than producing metals from raw feedstocks, where the primary metal sector emits approximately 10% of global GHG emissions from energy-intensive mining, smelting, and refining (Yokoi et al., 2022). Reprocessing 1 t of plastic waste can save up to 130 GJ of energy (Singh & Walker, 2024), and secondary production of plastics with a ~40% global collection rate could mitigate 160 Mt CO₂ /yr in 2050 (Daehn et al., 2022). Glass recycling offers 2–3% energy savings and a 5% reduction in CO₂ emissions from furnace fuel combustion for every 10% increase in cullet content in the melting batch (Baek et al., 2025; Glass Packaging Institute, n.d.; Miserocchi et al., 2024). 

We reiterate that GHG savings from recycling are highly sensitive to assumptions such as material quality, contamination rates, transportation distances, and market conditions. These factors introduce uncertainty because recycling benefits can vary depending on the efficiency of recycling systems in practice and market viability.

The results presented in this document summarize findings from 18 reports, 22 reviews and meta-analyses, 41 original studies, nine perspectives, two books, five web articles, and three datasets reflecting the most recent evidence for more than 200 countries. 

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Appendix

Market Revenue Variability of Recyclables

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Figure A1. The % revenue from recyclables compared to the % mass of each recyclable processed in an MRF. Values pertain to 2021.

Source: Bradshaw, S. L., Aguirre-Villegas, H. A., Boxman, S. E., & Benson, C. H. (2025). Material recovery facilities (MRFs) in the United States: Operations, revenue, and the impact of scale. Waste Management, 193, 317–327.

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Current Adoption

In addition to applying global recycling rates of 59.3%, 9%, and 21% to the total waste generated for paper and cardboard, plastics, and glass, respectively (World Bank, 2018; Table A1), we also calculated total tonnage recycled using reported recycling percentages and total MSW tonnage for each country. Combined recycled percentages were consistently lower than the total combined percentage of metal, paper and cardboard, plastic, and glass waste in MSW. This indicates ample opportunity for increased recycling, even in regions where it is already well established. 

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Table A1. Global recycling rates for each of the waste materials analyzed in this solution.

Waste material Global recycling rate (%) Reference
Metals 76a Charpentier Poncelet et al. (2022)
Paper and cardboard 59.3b European Paper Recycling Council (2020)
Plastics 9c OECD (2022b)
Glass 21d Ferdous et al. (2021)
Westbroek et al. (2021)

aEstimated using end-of-life recycling rates from Charpentier Poncelet et al. (2022), weighted by average annual global production for aluminum, copper, zinc, lead, iron, nickel, and manganese 2015–2019. We normalized weights against total metal production (1,619 Mt) to reflect each metal’s contribution to global scrap availability. This approach reflects the dominance of aluminum and iron in global scrap flows.

bBased on the average global paper recycling rate in 2018.

cBased on the global plastic recycling rate in 2019.

dBased on total glass produced in 2018 (a production-based recycling rate, meaning the share of recycled cullet used in total glass production), rather than on total glass waste generated (a waste-based recycling rate). We used this value due to a lack of consistent global data on postconsumer (end-of-life, old scrap) glass waste generation, although it may underestimate the recycling rate of actual discarded glass.

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Achievable Adoption

The World Bank (2018) also provided country-specific recycling rates and waste composition fractions of MSW for the materials we considered. Metals, paper and cardboard, plastics, and glass were reported as percentages of MSW by 169, 174, 173, and 168 countries, respectively. However, only 125 countries reported recycling rates, and these rates reflect combined MSW rather than material-specific recovery, so the dataset could not be used to estimate achievable adoption ranges for individual materials. 

Example Calculation of Achievable Adoption

For low achievable adoption, we assumed global recycling increases by 25% of the existing or most recently available rates or total recycled waste tonnage (i.e., recycling volumes) for all four materials except metals. For example, Delbari and Hof (2024) reported 2018 estimates of global glass recycling volumes at 27 Mt annually, so the Adoption – Low recycling rate was calculated at 34 Mt of glass waste recycled/yr. 

For high achievable adoption, we assume that global recycling rates increase by 50% of the existing or most recently available rates or total recycled waste tonnage (i.e., recycling volumes) for all four materials except metals. As an example, Houssini et al. (2025) reported global plastic production in 2022, from which 38 Mt were generated as secondary plastics from plastic mechanical recycling. Therefore, the high adoption recycling rate came out to 57 Mt of plastic waste recycled/yr.

Waste Sector Emissions

According to estimates by Ferdous et al. (2021), Ge et al. (2024), and Oo et al. (2024), the waste sector is responsible for 3.4–5% of total global GHG emissions, with solid waste management of landfills accounting for roughly two-thirds (Ge et al., 2024). In view of this and the energy-intensive production of raw materials, consistently improving recycling efficiency and rates can meaningfully mitigate the world’s carbon output.

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Sources

Bradshaw, S. L., Aguirre-Villegas, H. A., Boxman, S. E., & Benson, C. H. (2025). Material recovery facilities (MRFs) in the United States: Operations, revenue, and the impact of scale. Waste Management, 193, 317–327. https://doi.org/10.1016/j.wasman.2024.12.008

Charpentier Poncelet, A., Helbig, C., Loubet, P., Beylot, A., Muller, S., Villeneuve, J., Laratte, B., Thorenz, A., Tuma, A., & Sonnemann, G. (2022). Losses and lifetimes of metals in the economy. Nature Sustainability, 5(8), 717–726. https://doi.org/10.1038/s41893-022-00895-8

Delbari, S. A., & Hof, L. A. (2024). Glass waste circular economy—Advancing to high-value glass sheets recovery using industry 4.0 and 5.0 technologies. Journal of Cleaner Production, 462, Article 142629. https://doi.org/10.1016/j.jclepro.2024.142629

European Paper Recycling Council. (2020). European declaration on paper recycling 2016-2020: Monitoring report 2019. Confederation of European Paper Industries. https://www.cepi.org/wp-content/uploads/2020/10/EPRC-Monitoring-Report_2019.pdf 

Ferdous, W., Manalo, A., Siddique, R., Mendis, P., Zhuge, Y., Wong, H. S., Lokuge, W., Aravinthan, T., & Schubel, P. (2021). Recycling of landfill wastes (tyres, plastics and glass) in construction – A review on global waste generation, performance, application and future opportunities. Resources, Conservation and Recycling, 173, Article 105745. https://doi.org/10.1016/j.resconrec.2021.105745

Ge, M., Friedrich, J., & Vigna, L. (2024, December 5). Where do emissions come from? 4 charts explain greenhouse gas emissions by sector. World Resources Institute. https://www.wri.org/insights/4-charts-explain-greenhouse-gas-emissions-countries-and-sectors

Houssini, K., Li, J., & Tan, Q. (2025). Complexities of the global plastics supply chain revealed in a trade-linked material flow analysis. Communications Earth & Environment, 6(1), Article 257. https://doi.org/10.1038/s43247-025-02169-5

Oo, P. Z., Prapaspongsa, T., Strezov, V., Huda, N., Oshita, K., Takaoka, M., Ren, J., Halog, A., & Gheewala, S. H. (2024). The role of global waste management and circular economy towards carbon neutrality. Sustainable Production and Consumption, 52, 498–510. https://doi.org/10.1016/j.spc.2024.11.021

Organisation for Economic Co‑operation and Development. (2022b). Global plastics outlook: Economic drivers, environmental impacts and policy options [Report]. OECD Publishing. https://doi.org/10.1787/de747aef-en 

Westbroek, C. D., Bitting, J., Craglia, M., Azevedo, J. M. C., & Cullen, J. M. (2021). Global material flow analysis of glass: From raw materials to end of life. Journal of Industrial Ecology, 25(2), 333–343. https://doi.org/10.1111/jiec.13112

World Bank. (2018). What a waste global database: Country-level dataset (Last updated: 2024, June 4) [Data set]. https://datacatalogfiles.worldbank.org/ddh-published/0039597/3/DR0049199/country_level_data.csv

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Increase Centralized Composting

Submitted by Drawdown Admin on
Sector
Industry, Materials & Waste
Mode
Cut Emissions
Cluster
Use Waste as a Resource
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Centralized composting facility
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Summary

A composting system diverts organic waste (OW) from landfills, reducing the production of methane and other GHG emissions. OW is defined as the combination of food waste and green waste, composed of yard and garden trimmings. Composting transforms it into a nutrient-rich soil supplement.

Our focus is on centralized (city- or regional-level) composting systems for the OW components of municipal solid waste (MSW). Decentralized (home- and community-level) and on-farm composting are also valuable climate actions, but are not included here due to limited data availability at the global level (see Increase Decentralized Composting).

Income & work,Health,Equality
Land resources,Water resources,Air quality
Description for Social and Search
Increase Centralized Composting reduces methane and other GHG emissions by diverting organic waste from landfills to facilities that turn it into soil supplements.
Overview

There are many stages involved in a composting system to convert organic MSW into finished compost that can be used to improve soil health (Figure 1). Within this system, composting is the biochemical process that transforms OW into a soil amendment rich in nutrients and organic matter. 

Figure 1. Stages of a composting system. Solution boundaries exclude activities upstream and downstream of centralized MSW composting such as waste collection and compost application. Modified from Kawai et al. (2020) and Manea et al. (2024).

Diagram demonstrating process steps for landfill and compost materials.

Sources: Kawai, K., Liu, C., & Gamaralalage, P. J. D. (2020). CCET guideline series on intermediate municipal solid waste treatment technologies: Composting. United Nations Environment Programme; Manea, E. E., Bumbac, C., Dinu, L. R., Bumbac, M., & Nicolescu, C. M. (2024). Composting as a sustainable solution for organic solid waste management: Current practices and potential improvements.  Sustainability, 16(15), Article 6329.

The composting process is based on aerobic decomposition, driven by complex interactions among microorganisms, biodegradable materials, and invertebrates and mediated by water and oxygen (see the Appendix). Without the proper balance of oxygen and water, anaerobic decomposition occurs, leading to higher methane emissions during the composting process (Amuah et al., 2022; Manea et al., 2024). Multiple composting methods can be used depending on the amounts and composition of OW feedstocks, land availability, labor availability, finances, policy landscapes, and geography. Some common methods include windrow composting, bay or bin systems, and aerated static piles (Figure 2; Amuah et al., 2022; Ayilara et al., 2020; Cao et al., 2023).

Figure 2. Examples of commonly used centralized composting methods. Bay systems (left) move organics between different bays at different stages of the composting process. Windrows (center) are long, narrow piles that are often turned using large machinery. Aerated static piles (right) can be passively aerated as shown here or actively aerated with specialized blowing equipment.

Decentralized composting examples

Credit: Bays, iStock | nikolay100; Windrows, iStock | Jeremy Christensen; Aerated static pile, iStock | AscentXmedia

Centralized composting generally refers to processing large quantities (>90 t/week) of organic MSW (Platt, 2017). Local governments often manage centralized composting as part of an integrated waste management system that can also include recycling non-OW, processing OW anaerobically in methane digesters, landfilling, and incineration (Kaza et al., 2018). 

Organic components of MSW include food waste and garden and yard trimmings (Figure 2). In most countries and territories, these make up 40–70% of MSW, with food waste as the largest contribution (Ayilara et al., 2020; Cao et al., 2023; Food and Agriculture Organization [FAO], 2019; Kaza et al., 2018; Manea et al., 2024; U.S. Environmental Protection Agency [U.S. EPA], 2020; U.S. EPA, 2023). 

Diverting OW, particularly food waste, from landfill disposal to composting reduces GHG emissions (Ayilara et al., 2020; Cao et al., 2023; FAO, 2019). Diversion of organics from incineration could also have emissions and pollution reduction benefits, but we did not include incineration as a baseline disposal method for comparison since it is predominantly used in high-capacity and higher resourced countries and contributes less than 1% to annual waste-sector emissions (Intergovernmental Panel On Climate Change [IPCC], 2023; Kaza et al., 2018). 

Disposal of waste in landfills leads to methane emissions estimated at nearly 1.9 Gt CO₂‑eq (100-yr basis) annually (International Energy Agency [IEA], 2024). Landfill emissions come from anaerobic decomposition of inorganic waste and OW and are primarily methane with smaller contributions from ammonia, nitrous oxide, and CO₂ (Cao et al., 2023; Kawai et al., 2020; Manea et al., 2024). Although CO₂, methane, and nitrous oxide are released during composting, methane emissions are up to two orders of magnitude lower than emissions from landfilling for each metric ton of waste (Ayilara et al., 2020; Cao et al, 2023; FAO, 2019; IEA, 2024; Nordahl et al., 2023; Perez et al., 2023). GHG emissions can be minimized by fine-tuning the nutrient balance during composting. 

Depending on the specifics of the composting method used, the full transformation from initial feedstocks to finished compost can take weeks or months (Amuah et al., 2022; Manea et al., 2024; Perez et al., 2023). Finished compost can be sold and used in a variety of ways, including application to agricultural lands and green spaces as well as for soil remediation (Gilbert et al., 2020; Platt et al., 2022; Ricci-Jürgensen et al., 2020a; Sánchez et al., 2025). 

Abedin, T., Pasupuleti, J., Paw, J.K.S., Tak, Y. C., Islam, M. R., Basher, M. K., & Nur-E-Alam, M. (2025). From waste to worth: Advances in energy recovery technologies for solid waste management. Clean Technologies and Environmental Policy, 27, 5963–5989. Link to source: https://doi.org/10.1007/s10098-025-03204-x

Alves Comesaña, D., Villar Comesaña, I., & Mato de la Iglesia, S. (2024). Community composting strategies for biowaste treatment: Methodology, bulking agent and compost quality. Environmental Science and Pollution Research, 31(7), 9873–9885. Link to source: https://doi.org/10.1007/s11356-023-25564-x 

Amuah, E. E. Y., Fei-Baffoe, B., Sackey, L. N. A., Douti, N. B., & Kazapoe, R. W. (2022). A review of the principles of composting: Understanding the processes, methods, merits, and demerits. Organic Agriculture, 12(4), 547–562. Link to source: https://doi.org/10.1007/s13165-022-00408-z

Ayilara, M., Olanrewaju, O., Babalola, O., & Odeyemi, O. (2020). Waste management through composting: Challenges and potentials. Sustainability, 12(11), Article 4456. Link to source: https://doi.org/10.3390/su12114456

Bekchanov, M., & Mirzabaev, A. (2018). Circular economy of composting in Sri Lanka: Opportunities and challenges for reducing waste related pollution and improving soil health. Journal of Cleaner Production, 202, 1107–1119. Link to source: https://doi.org/10.1016/j.jclepro.2018.08.186

Bell, B., & Platt, B. (2014). Building healthy soils with compost to protect watersheds. Institute for Local Self-Reliance. Link to source: https://ilsr.org/wp-content/uploads/2013/05/Compost-Builds-Healthy-Soils-ILSR-5-08-13-2.pdf 

Brown, S. (2015, July 14). Connections: YIMBY. Biocycle. Link to source: https://www.biocycle.net/connections-yimby/

Cai, B., Lou, Z., Wang, J., Geng, Y., Sarkis, J., Liu, J., & Gao, Q. (2018). CH4 mitigation potentials from China landfills and related environmental co-benefits. Science Advances, 4(7), Article eaar8400. Link to source: https://doi.org/10.1126/sciadv.aar8400

Cao, X., Williams, P. N., Zhan, Y., Coughlin, S. A., McGrath, J. W., Chin, J. P., & Xu, Y. (2023). Municipal solid waste compost: Global trends and biogeochemical cycling. Soil & Environmental Health, 1(4), Article 100038. Link to source: https://doi.org/10.1016/j.seh.2023.100038

Casey, J. A., Cushing, L., Depsky, N., & Morello-Frosch, R. (2021). Climate justice and California’s methane superemitters: Environmental equity Assessment of community proximity and exposure intensity. Environmental Science & Technology, 55(21), 14746–14757. Link to source: https://doi.org/10.1021/acs.est.1c04328

Coker, C. (2020, March 3). Composting business management: Revenue forecasts for composters. Biocycle. Link to source: https://www.biocycle.net/composting-business-management-revenue-forecasts-composters/

Coker, C. (2020, March 10). Composting business management: Capital cost of composting facility construction. Biocycle. Link to source: https://www.biocycle.net/composting-business-management-capital-cost-composting-facility-construction/

Coker, C. (2020, March 17). Composting business management: Composting facility operating cost estimates. Biocycle. Link to source: https://www.biocycle.net/composting-business-management-composting-facility-operating-cost-estimates/ 

Coker, C. (2022, August 23). Compost facility planning: Composting facility approvals and permits. Biocycle. Link to source: https://www.biocycle.net/composting-facility-approval-permits/

Coker, C. (2022, September 27). Compost facility planning: Composting facility cost estimates. Biocycle. Link to source: https://www.biocycle.net/compost-facility-planning-cost/

Coker, C. (2024, August 20). Compost market development. Biocycle. Link to source: https://www.biocycle.net/compost-market-development/

European Energy Agency. (2024). Greenhouse gas emissions by source sector. (Last Updated: April 18, 2024). Eurostat. [Data set and codebook]. Link to source: https://ec.europa.eu/eurostat/databrowser/view/env_air_gge__custom_16006716/default/table 

Farhidi, F., Madani, K., & Crichton, R. (2022). How the US economy and environment can both benefit from composting management. Environmental Health Insights, 16. Link to source: https://doi.org/10.1177/11786302221128454

Food and Agriculture Organization of the United Nations. (2024). The state of food and agriculture 2024 – Value-driven transformation of agrifood systems. Link to source: https://doi.org/10.4060/cd2616en

Finlay, K. (2024). Turning down the heat: how the U.S. EPA can fight climate change by cutting landfill emissions. Industrious Labs. Link to source: https://cdn.sanity.io/files/xdjws328/production/657706be7f29a20fe54692a03dbedce8809721e8.pdf

Global Alliance for Incinerator Alternatives. (2019). Pollution and health impacts of waste-to-energy incineration [Fact sheet]. Link to source: https://www.cms.gov/newsroom/fact-sheets/delivering-service-school-based-settings-comprehensive-guide-medicaid-services-and-administrative

González, D., Barrena, R., Moral-Vico, J., Irigoyen, I., & Sánchez, A. (2024). Addressing the gaseous and odour emissions gap in decentralised biowaste community composting. Waste Management, 178, 231–238. Link to source: https://doi.org/10.1016/j.wasman.2024.02.042 

International Energy Agency. (2024), Global Methane Tracker 2024. Link to source: https://www.iea.org/reports/global-methane-tracker-2024

Intergovernmental Panel On Climate Change. (2023). Climate change 2022 – Impacts, adaptation and vulnerability: Working Group II contribution to the sixth assessment report of the Intergovernmental Panel on Climate Change (1st ed.). Cambridge University Press. Link to source: https://doi.org/10.1017/9781009325844

Intergovernmental Panel On Climate Change. (2019). 2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories, Calvo. Buendia, E., Tanabe, K., Kranjc, A., Baasansuren, J., Fukuda, M., Ngarize S., Osako, A., Pyrozhenko, Y., Shermanau, P. and Federici, S. (eds). Link to source: https://www.ipcc-nggip.iges.or.jp/public/2019rf/index.html 

Jamroz, E., Bekier, J., Medynska-Juraszek, A., Kaluza-Haladyn, A., Cwielag-Piasecka, I., & Bednik, M. (2020). The contribution of water extractable forms of plant nutrients to evaluate MSW compost maturity: A case study. Scientific Reports, 10(1), Article 12842. Link to source: https://doi.org/10.1038/s41598-020-69860-9

Kawai, K., Liu, C., & Gamaralalage, P. J. D. (2020). CCET guideline series on intermediate municipal solid waste treatment technologies: Composting. United Nations Environment Programme. Link to source: https://www.unep.org/ietc/resources/publication/ccet-guideline-series-intermediate-municipal-solid-waste-treatment

Kaza, S., Yao, L. C., Bhada-Tata, P., Van Woerden, F., (2018). What a waste 2.0: A global snapshot of solid waste management to 2050. Urban Development. World Bank. Link to source: http://hdl.handle.net/10986/30317 

Krause, M., Kenny, S., Stephenson, J., & Singleton, A. (2023). Quantifying methane emissions from landfilled food waste (Report No. EPA-600-R-23-064). U.S. Environmental Protection Agency Office of Research and Development. Link to source: https://www.epa.gov/system/files/documents/2023-10/food-waste-landfill-methane-10-8-23-final_508-compliant.pdf 

Liu, K-. M., Lin, S-. H., Hsieh, J-., C., Tzeng, G-., H. (2018). Improving the food waste composting facilities site selection for sustainable development using a hybrid modified MADM model. Waste Management, 75, 44–59. Link to source: https://doi.org/10.1016/j.wasman.2018.02.017

Liu, H., Zhang, X., & Hong, Q. (2021). Emission characteristics of pollution gases from the combustion of food waste. Energies, 14(19), Article 6439. Link to source: https://doi.org/10.3390/en14196439

Maalouf, A., & Agamuthu, P. (2023). Waste management evolution in the last five decades in developing countries – A review. Waste Management & Research: The Journal for a Sustainable Circular Economy, 41(9), 1420–1434. Link to source: https://doi.org/10.1177/0734242X231160099

Manea, E. E., Bumbac, C., Dinu, L. R., Bumbac, M., & Nicolescu, C. M. (2024). Composting as a sustainable solution for organic solid waste management: Current practices and potential improvements. Sustainability, 16(15), Article 6329. Link to source: https://doi.org/10.3390/su16156329

Martínez-Blanco, J., Lazcano, C., Christensen, T. H., Muñoz, P., Rieradevall, J., Møller, J., Antón, A., & Boldrin, A. (2013). Compost benefits for agriculture evaluated by life cycle assessment. A review. Agronomy for Sustainable Development, 33(4), 721–732. Link to source: https://doi.org/10.1007/s13593-013-0148-7

Martuzzi, M., Mitis, F., & Forastiere, F. (2010). Inequalities, inequities, environmental justice in waste management and health. The European Journal of Public Health, 20(1), 21–26. Link to source: https://doi.org/10.1093/eurpub/ckp216

Nordahl, S. L., Devkota, J. P., Amirebrahimi, J., Smith, S. J., Breunig, H. M., Preble, C. V., Satchwell, A. J., Jin, L., Brown, N. J., Kirchstetter, T. W., & Scown, C. D. (2020). Life-Cycle greenhouse gas emissions and human health trade-offs of organic waste management strategies. Environmental Science & Technology, 54(15), 9200–9209. Link to source: https://doi.org/10.1021/acs.est.0c00364 

Nordahl, S. L., Preble, C. V., Kirchstetter, T. W., & Scown, C. D. (2023). Greenhouse gas and air pollutant emissions from composting. Environmental Science & Technology, 57(6), 2235–2247. Link to source: https://doi.org/10.1021/acs.est.2c05846 

Nubi, O., Murphy, R., & Morse, S. (2024). Life cycle sustainability assessment of waste to energy systems in the developing world: A review. Environments, 11(6), 123. https://doi.org/10.3390/environments11060123

Organisation for Economic Co-operation and Development. (2021). Waste - Municipal waste: generation and treatment. (Downloaded: March 20, 2025) [Data set]. Link to source: https://data-explorer.oecd.org/vis?lc=en&df[ds]=dsDisseminateFinalDMZ&df[id]=DSD_MUNW%40DF_MUNW&df[ag]=OECD.ENV.EPI&dq=.A.INCINERATION_WITHOUT%2BLANDFILL.T&pd=2014%2C&to[TIME_PERIOD]=false&vw=ov 

Pérez, T., Vergara, S. E., & Silver, W. L. (2023). Assessing the climate change mitigation potential from food waste composting. Scientific Reports, 13(1), Article 7608. Link to source: https://doi.org/10.1038/s41598-023-34174-z

Platt, B., Bell, B., & Harsh, C. (2013). Pay dirt: Composting in Maryland to reduce waste, create jobs, & protect the bay. Institute for Local Self-Reliance. Link to source: https://ilsr.org/wp-content/uploads/2013/05/Pay-Dirt-Report.pdf

Platt, B. (2017, April 4). Hierarchy to Reduce Food Waste & Grow Community, Institute for Local Self-Reliance. Link to source: https://ilsr.org/articles/food-waste-hierarchy/

Platt, B., and Fagundes, C. (2018). Yes! In my backyard: A home composting guide for local government. Institute for Local Self-Reliance. Link to source: https://ilsr.org/articles/yimby-compost/

Platt, B., Libertelli, C., & Matthews, M. (2022). A growing movement: 2022 community composter census. Institute for Local Self-Reliance. Link to source: https://ilsr.org/articles/composting-2022-census/ 

Ricci-Jürgensen, M., Gilbert, J., & Ramola, A.. (2020a). Global assessment of municipal organic waste production and recycling. International Solid Waste Association. Link to source: https://www.altereko.it/wp-content/uploads/2020/03/Report-1-Global-Assessment-of-Municipal-Organic-Waste.pdf 

Ricci-Jürgensen, M., Gilbert, J., & Ramola, A.. (2020b). Benefits of compost and anaerobic digestate when applied to soil. International Solid Waste Association. Link to source: https://www.altereko.it/wp-content/uploads/2020/03/Report-2-Benefits-of-Compost-and-Anaerobic-Digestate.pdf 

Rynk, R., Black, G., Biala, J., Bonhotal, J., Cooperband, L., Gilbert, J., & Schwarz, M. (Eds.). (2021). The composting handbook. Compost Research & Education Foundation and Elsevier. Link to source: https://www.compostingcouncil.org/store/viewproduct.aspx?id=19341051

Sánchez, A., Gea, T., Font, X., Artola, A., Barrena, R., & Moral-Vico, J. (Eds.). (2025). Composting: Fundamentals and Recent Advances: Chapter 1. Royal Society of Chemistry. Link to source: https://doi.org/10.1039/9781837673650 

Searchinger, T., Peng, L., Zionts, J., & Waite, R. (2024). The global land squeeze: Managing the growing competition for land. World Resources Institute. Link to source: https://www.wri.org/research/global-land-squeeze-managing-growing-competition-land

Souza, M. A. d., Gonçalves, J. T., & Valle, W. A. d. (2023). In my backyard? Discussing the NIMBY effect, social acceptability, and residents’ involvement in community-based solid waste management. Sustainability, 15(9), Article 7106. Link to source: https://doi.org/10.3390/su15097106

The Environmental Research & Education Foundation. (2024). Analysis of MSW landfill tipping fees — 2023. Link to source: https://erefdn.org/product/analysis-of-msw-landfill-tipping-fees-2023/

U.S. Composting Council. (2008). Greenhouse gases and the role of composting: A primer for compost producers [Fact sheet]. Link to source: https://cdn.ymaws.com/www.compostingcouncil.org/resource/resmgr/documents/GHG-and-Role-of-Composting-a.pdf 

U.S. Environmental Protection Agency. (2020). 2018 wasted food report (EPA Publication No. EPA 530-R-20-004). Office of Resource Conservation and Recovery. Link to source: https://www.epa.gov/system/files/documents/2025-02/2018_wasted_food_report-v2.pdf 

U.S. Environmental Protection Agency. (2023). 2019 Wasted food report (EPA Publication No. 530-R-23-005). National Institutes of Health. Link to source: https://www.epa.gov/system/files/documents/2024-04/2019-wasted-food-report_508_opt_ec_4.23correction.pdf

U.S. Environmental Protection Agency. (2023). Documentation for Greenhouse Gas Emission and Energy Factors Used in the Waste Reduction Model (WARM): Organic Materials Chapters (EPA Publication No. EPA-530-R-23-019). Office of Resource Conservation and Recovery. Link to source: https://www.epa.gov/system/files/documents/2023-12/warm_organic_materials_v16_dec.pdf

U.S. Environmental Protection Agency. (2025, January). Approaches to composting. Link to source: https://www.epa.gov/sustainable-management-food/approaches-composting

U.S. Environmental Protection Agency. (2025, April). Benefits of using compost. Link to source: https://www.epa.gov/sustainable-management-food/benefits-using-compost

United Nations Environment Programme. (2023). Towards Zero Waste: A Catalyst for delivering the Sustainable Development Goals. Link to source: https://doi.org/10.59117/20.500.11822/44102

United Nations Environment Programme. (2024). Global Waste Management Outlook 2024 Beyond an age of waste: Turning rubbish into a resource. Link to source: https://www.unep.org/resources/global-waste-management-outlook-2024 

Urra, J., Alkorta, I., & Garbisu, C. (2019). Potential benefits and risks for soil health derived from the use of organic amendments in agriculture. Agronomy, 9(9), 542. Link to source: https://doi.org/10.3390/agronomy9090542

Wilson, D. C., Paul, J., Ramola, A., & Filho, C. S. (2024). Unlocking the significant worldwide potential of better waste and resource management for climate mitigation: With particular focus on the Global South. Waste Management & Research: The Journal for a Sustainable Circular Economy, 42(10), 860–872. Link to source: https://doi.org/10.1177/0734242X241262717

World Bank. (2018). What a waste global database: Country-level dataset. (Last Updated: June 4, 2024) [Data set]. World Bank. Link to source: https://datacatalogfiles.worldbank.org/ddh-published/0039597/3/DR0049199/country_level_data.csv 

Yasmin, N., Jamuda, M., Panda, A. K., Samal, K., & Nayak, J. K. (2022). Emission of greenhouse gases (GHGs) during composting and vermicomposting: Measurement, mitigation, and perspectives. Energy Nexus, 7, Article 100092. Link to source: https://doi.org/10.1016/j.nexus.2022.100092

Zaman, A. U. (2016). A comprehensive study of the environmental and economic benefits of resource recovery from global waste management systems. Journal of Cleaner Production, 124, 41–50. Link to source: https://doi.org/10.1016/j.jclepro.2016.02.086

Zero Waste Europe & Bio-based Industries Consortium. (2024). Bio-waste generation in the EU: Current capture levels and future potential (Second edition). LIFE Programme of the European Union. Link to source: https://zerowasteeurope.eu/library/bio-waste-generation-in-the-eu-current-capture-levels-and-future-potential-second-edition/ 

Zhu, J., Luo, Z., Sun, T., Li, W., Zhou, W., Wang, X., Fei, X., Tong, H., & Yin, K. (2023). Cradle-to-grave emissions from food loss and waste represent half of total greenhouse gas emissions from food systems. Nature Food, 4(3), 247–256. Link to source: https://doi.org/10.1038/s43016-023-00710-3

Credits

Lead Fellow

  • Megan Matthews, Ph. D.

Contributors

  • Ruthie Burrows, Ph.D.

  • James Gerber, Ph.D.

  • Daniel Jasper

  • Alex Sweeney

Internal Reviewers

  • Aiyana Bodi

  • Hannah Henkin

  • Ted Otte

  • Sarah Gleeson, Ph. D.

  • Amanda D. Smith, Ph.D.

  • Paul C. West, Ph.D.

Effectiveness

We estimated that composting reduces emissions by 3.9 t CO₂‑eq /t OW (9.3 t CO₂‑eq /t OW, 20-yr basis) based on avoided landfill emissions minus the emissions during composting of MSW OW (Table 1). In our analysis, composting emissions were an order of magnitude lower than landfill emissions.

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Table 1. Effectiveness at reducing emissions. 

Unit: t CO₂‑eq (100-yr basis)/t OW

25th percentile 2.5
Mean 3.2
Median (50th percentile) 3.9
75th percentile 4.3
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Emissions data from composting and landfilling OW are geographically limited, but our analysis includes three global reports and studies from the U.S., China, Denmark, and the EU (European Energy Agency [EEA], 2024; Industrious Labs, 2024; Perez et al., 2023; U.S. EPA, 2020; Yang et al., 2017, Yasmin et al., 2022). We assumed OW was 39.6% of MSW in accordance with global averages (Kaza et al., 2018; World Bank, 2018).

We estimated that landfills emit 4.3 t CO₂‑eq /t OW (9.9 t CO₂‑eq /t OW, 20-yr basis). We estimated composting emissions were 10x lower at 0.4 t CO₂‑eq /t OW (0.6 t CO₂‑eq /t OW, 20-yr basis). We quantified emissions from a variety of composting methods and feedstock mixes (Cao et al., 2023; Perez et al., 2023; Yasmin et al., 2022). Consistent with Amuah et al. (2022), we assumed a 60% moisture content by weight to convert reported wet waste quantities to dry waste weights. We based effectiveness estimates only on dry OW weights. For adoption and cost, we did not distinguish between wet and dry OW.

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Cost

Financial data were geographically limited. We based cost estimates on global reports with selected studies from the U.K., U.S., India, and Saudi Arabia for landfilling and the U.S. and Sri Lanka for composting. Transportation and collection costs can be significant in waste management, but we did not include them in this analysis. We calculated amortized net cost for landfilling and composting by subtracting revenues from operating costs and amortized initial costs over a 30-yr facility lifetime.

Landfill initial costs are one-time investments, while operating expenses, which include maintenance, wages, and labor, vary annually. Environmental costs, including post-closure operations, are not included in our analysis, but some countries impose taxes on landfilling to incentivize alternative disposal methods and offset remediation costs. Landfills generate revenue through tip fees and sales of landfill gas (Environmental Research & Education Foundation [EREF], 2023; Kaza et al., 2018). We estimated that landfilling is profitable, with a net cost of –US$30/t OW. 

Initial and operational costs for centralized composting vary depending on method and scale (IPCC, 2023; Manea et al., 2024), but up-front costs are generally cheaper than landfilling. Since composting is labor-intensive and requires monitoring, operating costs can be higher, particularly in regions that do not impose landfilling fees (Manea et al., 2024). 

Composting facilities generate revenue through tip fees and sales of compost products. Compost sales alone may not be sufficient to recoup costs, but medium- to large-scale composting facilities are economically viable options for municipalities (Kawai et al., 2020; Manea et al., 2024). We estimated the net composting cost to be US$20/t OW. The positive value indicates that composting is not globally profitable; however, decentralized systems that locally process smaller waste quantities can be profitable using low-cost but highly efficient equipment and methods (see Increase Decentralized Composting). 

We estimated that composting costs US$50/t OW more than landfilling. Although composting systems cost more to implement, the societal and environmental costs are greatly reduced compared to landfilling (Yasmin et al., 2022). The high implementation cost is a barrier to adoption in lower-resourced and developing countries (Wilson et al., 2024). 

Combining effectiveness with the net costs presented here, we estimated a cost per unit climate impact of US$10/t CO₂‑eq (US$5/t CO₂‑eq , 20-yr basis) (Table 2). 

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Table 2. Cost per unit climate impact.

Unit: US$ (2023)/t CO₂‑eq (100-yr basis)

Median 10
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Learning Curve

Global cost data on composting are limited, and costs can vary depending on composting methods, so we did not quantify a learning rate for centralized composting.

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Speed of Action

Speed of action refers to how quickly a climate solution physically affects the atmosphere after it is deployed. This is different from speed of deployment, which is the pace at which solutions are adopted.

At Project Drawdown, we define the speed of action for each climate solution as emergency brake, gradual, or delayed.

Increase Centralized Composting is an EMERGENCY BRAKE climate solution. It has the potential to deliver a more rapid impact than nominal and delayed solutions. Because emergency brake solutions can deliver their climate benefits quickly, they can help accelerate our efforts to address dangerous levels of climate change. For this reason, they are a high priority.

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Caveats

The composting process has a low risk of reversal since carbon is stored stably in finished compost instead of decaying and releasing methane in a landfill (Ayilara et al., 2020; Manea et al., 2024). However, a composting system, from collection to finished product, can be challenging to sustain. Along with nitrogen-rich food and green waste, additional carbon-rich biomass, called bulking material, is critical for maintaining optimal composting conditions that minimize GHG emissions. Guaranteeing the availability of sufficient bulking materials can challenge the success of both centralized and decentralized facilities.

Financially and environmentally sustainable composting depends not only on the quality of incoming OW feedstocks, but also on the quality of the final product. Composting businesses require a market for sales of compost products (in green spaces and/or agriculture), and poor source separation could lead to low-quality compost and reduced demand (Kawai et al., 2020; Wilson et al., 2024). Improvements in data collection and quality through good feedback mechanisms can also act as leverage for expanding compost markets, pilot programs, and growing community support.

If composting facilities close due to financial or other barriers, local governments may revert to disposing of organics in landfills. Zoning restrictions also vary broadly across geographies, affecting how easily composting can be implemented (Cao et al., 2023). In regions where centralized composting is just starting, reversal could be more likely without community engagement and local government support (Kawai et al., 2020; Maalouf & Agamuthu, 2023); however, even if facilities close, the emissions savings from past operation cannot be reversed.

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Current Adoption

We estimated global composting adoption at 78 million t OW/yr, as the median between two datasets (Table 3). The most recent global data on composting were compiled in 2018 from an analysis from 174 countries and territories (World Bank, 2018). We also used an Organisation for Economic Co-operation and Development (OECD) analysis from 45 countries (OECD, 2021). However, there were still many countries and territories that did not report composting data in one or both datasets. Although the World Bank dataset is comprehensive, it is based on data collected in 2011–2018, so more recent, high-quality, global data on composting are needed.

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Table 3. Current adoption level (2021).

Unit: t OW composted/yr

25th percentile 67,000,000
Mean 78,000,000
Median (50th percentile) 78,000,000
75th percentile 89,000,000
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Globally in 2018, nearly 40% of all waste was disposed of in landfills, 19% was recovered through composting and other recovery and recycling methods, and the remaining waste was either unaccounted for or disposed of through open dumping and wastewater (Kaza et al., 2018)

We calculated total tonnage composted using the reported composting percentages and the total MSW tonnage for each country. Composting percentages were consistently lower than the total percentage of OW present in MSW, suggesting there is ample opportunity for increased composting, even in geographies where it is an established disposal method. In 2018, 26 countries/territories had a composting rate above 10% of MSW, and 15 countries/territories had a composting rate above 20% of MSW. Countries with the highest composting rates were Austria (31%), the Netherlands (27%), and Switzerland (21%) (World Bank, 2018).

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Adoption Trend

We used OECD data to estimate the composting adoption trend from 2014–2021 (OECD, 2021), which fluctuated significantly from year to year (Table 4). Negative rates indicate less OW was composted globally than in the previous year. Taking the median composting rate across seven years, we estimate the global composting trend as 260,000 t OW/yr/yr. However, the mean composting trend is –1.3 Mt OW/yr/yr, suggesting that on average, composting rates are decreasing globally. 

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Table 4. Adoption trend (2014–2021).

Unit: t OW composted/yr/yr

25th percentile -1,200,000
Mean -1,300,000
Median (50th percentile) 260,000
75th percentile 4,300,000
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Although some regions are increasing their composting capacity, others are either not composting or composting less over time. Germany, Italy, Spain, and the EU overall consistently show increases in composting rates year-to-year, while Greece, Japan, Türkiye, and the U.K. show decreasing composting rates. In Europe, the main drivers for consistent adoption were disposal costs, financial penalties, and the landfill directive (Ayilara et al., 2020). 

Lack of reported data could also contribute to a negative global average composting rate over the past seven years. A large decline in composting rates from 2018–2019 was driven by a lack of data in 2019 for the U.S. and Canada. If we assumed that the U.S. composted the same tonnage in 2019 as in 2018, instead of no tonnage as reported in the data, then the annual trend for 2018–2019 is much less negative (–450,000 t OW/yr/yr) and the overall mean trend between 2014–2019 would be positive (1,400,000 t OW/yr/yr).

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Adoption Ceiling

We estimate the global adoption ceiling for Increase Centralized Composting to be 1.35 billion t OW/yr (Table 5). In 2016, 2.01 Gt of MSW were generated, and generation is expected to increase to 3.4 Gt by 2050 (Kaza et al., 2018). Due to limited global data availability on composting infrastructure or policies, we estimated the adoption ceiling based on the projected total MSW for 2050 and assumed the OW fraction remains the same over time.

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Table 5. Adoption ceiling. upper limit for adoption level.

Unit: t OW composted/yr

Median (50th percentile) 1,350,000,000
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In reality, amounts of food waste within MSW are also increasing, suggesting that there are sufficient global feedstocks to support widespread composting adoption (Zhu et al., 2023). 

We assume that all OW could be processed via composting, but this ceiling is unlikely to be reached. In practice, organics could also be processed via methane digesters (see Deploy Methane Digesters), incinerated, or dumped, but these waste management treatments have similar environmental risks to landfilling. 

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Achievable Adoption

Since the global annual trend fluctuates, we used country-specific composting rates and organic fractions of MSW from 2018 to estimate the achievable range of composting adoption (see Appendix for an example). In our analysis, achievable increases in country-specific composting rates cannot exceed the total organic fraction of 2018 MSW. 

For the 106 countries/territories that did not report composting rates, we defined achievable levels of composting relative to the fraction of OW in MSW. When countries also did not report OW percentages, the country-specific composting rate was kept at zero. For the remaining 86 countries/territories, we assumed that 25% of organic MSW could be diverted to composting for low achievable adoption and that 50% could be diverted for high achievable adoption. 

For the 68 countries/territories with reported composting rates, we define low and high achievable adoption as a 25% or 50% increase to the country-specific composting rate, respectively. If the increased rate for either low or high adoption exceeded the country-specific OW fraction of MSW, we assumed that all organic MSW could be composted (see Appendix for an example). Our Achievable – Low adoption level is 201 Mt OW/yr, or 15% of our estimated adoption ceiling (Table 6). Our Achievable – High adoption level is 301 Mt OW/yr, or 22% of our estimated adoption ceiling. 

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Table 6. Range of achievable adoption levels.

Unit: t OW composted/yr

Current adoption 78,000,000
Achievable – low 201,000,000
Achievable – high 301,000,000
Adoption ceiling 1,350,000,000
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Our estimated adoption levels are conservative because some regions without centralized composting of MSW could have subnational decentralized composting programs that aren’t reflected in global data.

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Although our achievable range is conservative compared to the estimated adoption ceiling, increased composting has the potential to reduce GHG emissions from landfills (Table 7). We estimated that current adoption reduces annual GHG emissions by 0.3 Gt CO₂‑eq/yr (0.73 Gt CO₂‑eq/yr, 20-yr basis). Our estimated low and high achievable adoption levels reduce 0.78 and 1.2 Gt CO₂‑eq/yr (1.9 and 2.8 Gt CO₂‑eq/yr, 20-yr basis), respectively. Using the adoption ceiling, we estimate that annual GHG reductions increase to 5.2 Gt CO₂‑eq/yr (12.6 Gt CO₂‑eq/yr, 20-yr basis).

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Table 7. Climate impact at different levels of adoption.

Unit: Gt CO₂‑eq (100-yr basis)/yr

Current adoption 0.30
Achievable – low 0.78
Achievable – high 1.2
Adoption ceiling 5.2
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The IPCC estimated in 2023 that the entire waste sector accounted for 3.9% of total global GHG emissions, and solid waste management represented 36% of total waste sector emissions (IPCC, 2023). Disposal of waste in landfills leads to methane emissions estimated at nearly 1.9 Gt CO₂‑eq (100-yr basis) annually (IEA, 2024). Based on these estimates, current composting adoption reduces annual methane emissions from landfills more than 16%. 

Increasing adoption to low and high achievable levels could reduce the amount of OW going to landfills by up to 40% and avoid 32–50% of landfill emissions. Reaching our estimated adoption ceilings for Increase Centralized Composting and reduction-focused solutions like Reduce Food Loss and Waste could avoid all food-related landfill emissions.

These climate impacts can be considered underestimates of beneficial mitigation from increased composting since we did not quantify the carbon sequestration benefits of compost application and reduced synthetic fertilizer use. Our estimated climate impacts from composting are also an underestimate because we didn’t include decentralized composting. 

In addition to OW from MSW, large-scale composting also requires agricultural biomass as a feedstock. Multiple climate solutions, in addition to Increase Centralized Composting, require biomass, and projected demand across solutions greatly exceeds supply. The deforestation that would be required to meet demand would produce emissions far greater than any mitigation gains from full deployment of these solutions (Searchinger, 2024). In addition to deforestation, there would also be costs and emissions incurred to transport biomass from where it is produced to where it can be processed and used. Thus, the estimated climate impacts presented here are only possible if feedstocks are prioritized for this solution. If feedstocks are instead prioritized for other climate solutions (see Interactions for examples), adoption and impact will be lower for this solution. It is not possible to set all biomass-dependent solutions to high adoption levels, add up their impacts, and determine an accurate combined emissions impact.

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Additional Benefits

Income and Work

Composting creates more jobs than landfills or incinerators and can save money compared with other waste management options (Bekchanov & Mirzabaev, 2018; Farhidi et al., 2022; Platt et al., 2013; Zaman, 2016). It is less expensive to build and maintain composting plants than incinerators (Kawai et al., 2020). According to a survey of Maryland waste sites, composting creates twice as many jobs as landfills and four times as many jobs as incineration plants (Platt et al., 2013). Composting also indirectly sustains jobs in the distribution and use of compost products (Platt et al., 2013). Compost is rich in nutrients and can also reduce costs associated with synthetic fertilizer use in agriculture (Farhidi et al., 2022).

Health

Odors coming from anaerobic decomposition landfills, such as ammonia and hydrogen sulfide, are another source of pollutants that impact human well-being, which can be reduced by aerobic composting (Cai et al., 2018).

Equality

Reducing community exposure to air pollution from landfills through composting has implications for environmental justice (Casey et al., 2021; Nguyen et al., 2023). A large review of waste sites in the United States and Europe found that landfills are disproportionately located near populations with low socioeconomic status and near racially and ethnically marginalized neighborhoods (Marzutti et al., 2010). Reducing disproportionate exposures to air pollution from landfills may mitigate poor health outcomes in surrounding communities (Brender et al., 2011)

Land Resources

Compost provides an important soil amendment that adds organic matter and nutrients to soil, reducing the need for synthetic fertilizers (Urra et al., 2019; U.S. EPA, 2025). Healthy soils that are rich in organic matter can benefit the surrounding ecosystem and watershed and lead to more plant growth through improved water retention and filtration, improved soil quality and structure, and reduced erosion and nutrient runoff (Bell & Platt, 2014; Martinez-Blanco et al., 2013; U.S. EPA, 2025). By reducing the need for synthetic fertilizers and by improving soils’ ability to filter and conserve water, compost can also reduce eutrophication of water bodies (U.S. EPA, 2025). These soil benefits are partially dependent on how compost is sorted because there may be risks associated with contamination of microplastics and heavy metals (Manea et al., 2024; Urra et al., 2019).

Water Resources

For a description of water resources benefits, please see Land Resources above. 

Air Quality

Composting can reduce air pollution such as CO₂, methane, volatile organic compounds, and particulate matter that is commonly released from landfills and waste-to-energy systems (Kawai et al., 2020; Nordahl et al., 2020; Siddiqua et al., 2022). An analysis comparing emissions from MSW systems found composting to have lower emissions than landfilling and other waste-to-energy streams (Nordahl et al., 2020). Composting can also reduce the incidence of landfill fires, which release black carbon and carbon monoxide, posing risks to the health and safety of people in nearby communities (Nguyen et al., 2023).

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Risks

Before the composting process can start, feedstocks are sorted to remove potential contaminants, including nonbiodegradable materials such as metal and glass as well as plastics, bioplastics, and paper products (Kawai et al., 2020; Perez et al., 2023; Wilson et al., 2024). While most contaminants can be removed through a variety of manual and mechanical sorting techniques, heavy metals and microplastics can become potential safety hazards or reduce finished compost quality (Manea et al., 2024). Paper and cardboard should be separated from food and green waste streams because they often contain contaminants such as glue or ink, and they degrade more slowly than other OW, leading to longer processing time and lower-quality finished compost (Kawai et al., 2020; Krause et al., 2023).

Successful and safe composting requires careful monitoring of compost piles to avoid anaerobic conditions and ensure sufficient temperatures to kill pathogens and weed seeds (Amuah et al., 2022; Ayilara et al., 2020; Cao et al., 2023; Kawai et al., 2020; Manea et al., 2024). Anaerobic conditions within the compost pile increase GHGs emitted during composting. Poorly managed composting facilities can also pose safety risks for workers and release odors, leading to community backlash (Cao et al., 2023; Manea et al., 2024; UNEP, 2024). Regional standards, certifications, and composter training programs are necessary to protect workers from hazardous conditions and to guarantee a safe and effective compost product (Kawai et al., 2020). Community outreach and education on the benefits of separating waste and composting prevent “not-in-my-backyard” attitudes or “NIMBYism” (Brown, 2015; Platt & Fagundes 2018) that may lead to siting composting facilities further from the communities they serve (Souza, et al., 2023; Liu et al., 2018).

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Interactions with Other Solutions

Reinforcing

Increased composting could positively impact annual cropping by providing consistent, high-quality finished compost that can reduce dependence on synthetic fertilizers and improve soil health and crop yields. 

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High-quality sorting systems also allow for synergies that benefit all waste streams and create flexible, resilient waste management systems. Improving waste separation programs for composting can have spillover effects that also improve other waste streams, such as recyclables, agricultural waste, or e-waste. Access to well-sorted materials can also help with nutrient balance for various waste streams, including agricultural waste.

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Composting facilities require a reliable source of carbon-rich bulking material. Agricultural waste can be diverted to composting rather than burning to reduce emissions from crop residue burning. 

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Competing

Diverting OW from landfills will lead to lower landfill methane emissions and, therefore, less methane available to be captured and resold as revenue.

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Composting uses wood, crop residues, and food waste as feedstocks (raw material). Because the total projected demand for biomass feedstocks for climate solutions exceeds the supply, not all solutions will be able to achieve their potential adoption. This solution is in competition with other climate solutions for raw material.

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Dashboard

Solution Basics

t organic waste

t CO₂-eq (100-yr)/unit
02.53.9
units/yr
Current 7.8×10⁷ 02.009×10⁸3.01×10⁸
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 0.3 0.781.2
US$ per t CO₂-eq
10
Emergency Brake

CO₂,  CH₄

Trade-offs

Robust collection networks and source separation of OW are vital for successful composting, but they also increase investment costs. However, well-sorted OW can reduce the need for separation equipment and allow for simpler facility designs, leading to lower operational costs. The emissions from transporting OW are not included here, but are expected to be significantly less than the avoided landfill emissions. Composting facilities are typically located close to the source of OW (Kawai et al., 2020; U.S. Composting Council [USCC], 2008), but since centralized composting facilities are designed to serve large communities and municipalities, there can be trade-offs between sufficient land availability and distance from waste sources.

We also exclude emissions from onsite vehicles and equipment such as bulldozers and compactors, assuming that those emissions are small compared to the landfill itself.

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t/person/yr
< 0.17
0.17–0.32
0.32–0.5
> 0.5
No Data

Per capita MSW generation, 2018

Annual generation of MSW per capita. Total global MSW generation exceeded 2 Gt/yr.

World Bank Group (2021). What a waste global database (Version 3) [Data set]. WBG. Retrieved March 6, 2025, from Link to source: https://datacatalog.worldbank.org/search/dataset/0039597

t/person/yr
< 0.17
0.17–0.32
0.32–0.5
> 0.5
No Data

Per capita MSW generation, 2018

Annual generation of MSW per capita. Total global MSW generation exceeded 2 Gt/yr.

World Bank Group (2021). What a waste global database (Version 3) [Data set]. WBG. Retrieved March 6, 2025, from Link to source: https://datacatalog.worldbank.org/search/dataset/0039597

Maps Introduction

Globally, 17 countries reported composting more than 1 Mt each of organic waste in 2018, with India, China, Germany, and France reporting more than 5 Mt each (World Bank, 2018). With the exception of Austria, which composted nearly all organic waste generated, even countries with established centralized composting could divert more organic waste to composting. 

The fate from which composting diverts organic waste varies from region to region, but globally over 40% of all waste ends up in landfills. Since organic waste makes up the largest percentage of MSW in most regions, excluding North America, parts of East Asia and the Pacific, and parts of Europe and Central Asia, there is ample opportunity to increase composting. In East Asia and the Pacific, South Asia, and sub-Saharan Africa, diverting organics to composting also avoids disposal in waterways and open dumps, which reduces pollution. In North America and Europe and Central Asia, 15–20% of MSW is incinerated (Kaza et al., 2018), so diverting all organic waste to composting would avoid harmful incineration emissions including CO, NOx, and VOCs (Abedin et al., 2025; Global Alliance for Incinerator Alternatives, 2019; Liu et al., 2021; Nubi et al., 2024).

Diversion of organic waste requires separation of waste streams, and cities with better collection and tracking networks often have more robust composting programs. Higher quality and more frequent reporting on waste generation and disposal worldwide could improve source separation and increase composting. Additionally, city-level and decentralized pilot programs allow for better control over feedstock collection and can bolster support for larger scale, centralized operations. 

Multiple cities in Latin America and the Caribbean represent a resurgence in composting markets . In the 1960s and 1970s, composting facilities were built in cities across Mexico, El Salvador, Ecuador, Venezuela, and Brazil, but many closed due to high operational costs (Ricci-Jürgensen et al., 2020a). In 2018, 15% of waste was recycled or composted in Montevideo, Uruguay, and Bogotá and Medellín, Colombia, and 10% of waste was composted in Mexico City, Mexico, and Rosario, Argentina (Kaza et al., 2018).  

Waste generation is increasing globally, with the largest increases projected to occur in sub-Saharan Africa, South Asia, and the Middle East and North Africa (Kaza et al., 2018). As waste generation doubles or triples in these regions, sustainable disposal methods will become more critical for human health and well-being. 

In 2018, Ethiopia reported the highest organic waste percentage in sub-Saharan Africa at 85% of MSW, but no composting (World Bank, 2018). Organic waste percentages are high in other countries in the region, so composting could be a valuable method to handle the growing waste stream. In the Middle East & North Africa, 43% of countries reported composting as of 2018 (Kaza et al., 2018), indicating the presence of infrastructure that could be scaled up to handle increased waste in the future.

Action Word
Increase
Solution Title
Centralized Composting
Classification
Highly Recommended
Lawmakers and Policymakers
  • Establish zero waste and OW diversion goals; incorporate them into local or national climate plans and soil health and conservation policies.
  • Ensure public procurement uses local compost when possible.
  • Participate in consultations with farmers, businesses, and the public to determine where to place plants, how to use compost, pricing, and how to roll out programs.
  • Establish or improve existing centralized composting facilities, collection networks, and storage facilities.
  • Establish incentives and programs to encourage both centralized and decentralized composting.
  • Work with farmers, local gardeners, the private sector, and local park systems to develop markets for compost.
  • Invest in source separation education and waste separation technology that enhances the quality of final compost products.
  • Regulate the use of waste separation technologies to prioritize source separation of waste and the quality of compost products.
  • Ensure low- and middle-income households are served by composting programs with particular attention to underserved communities such as multi-family buildings and rural households.
  • Enact extended producer responsibility approaches that hold producers accountable for waste.
  • Create demonstration projects to show the effectiveness and safety of finished compost.
  • Ensure composting plants are placed as close to farmland as possible and do not adversely affect surrounding communities.
  • Streamline permitting processes for centralized compost facilities and infrastructure.
  • Establish laws or regulations that require waste separation as close to the source as possible, ensuring the rules are effective and practical.
  • Establish zoning policies that support both centralized and decentralized composting efforts, including at the industrial, agricultural, community, and backyard scales.
  • Establish fees or fines for OW going to landfills; use funds for composting programs.
  • Use financial instruments such as taxes, subsidies, or exemptions to support infrastructure, participation, and waste separation.
  • Partner with schools, community gardens, farms, nonprofits, women’s groups, and other community organizations to promote composting and teach the importance of waste separation.
  • Establish one-stop-shop educational programs that use online and in-person methods to teach how to separate waste effectively and why it’s important.
  • If composting is not possible or additional infrastructure is needed, consider methane digesters as alternatives to composting.
  • Create, support, or join certification programs that verify the quality of compost and/or verify food waste suppliers such as hotels, restaurants, and cafes.

Further information:

Practitioners
  • Work with policymakers and local communities to establish zero-waste and OW diversion goals for local or national climate plans.
  • Participate in consultations with farmers, policymakers, businesses, and the public to determine where to place plants, how to use compost, pricing, and how to roll out programs.
  • Work with farmers, local gardeners, the private sector, and local park systems to create quality supply streams and develop markets for compost.
  • Invest in source separation education and waste separation technology that enhances the quality of final compost products.
  • Establish one-stop-shop educational programs that use online and in-person methods to teach how to separate waste effectively and why that’s important.
  • Ensure low- and middle-income households are served by composting programs with particular attention to underserved communities such as multi-family buildings and rural households.
  • Create demonstration projects to show the effectiveness and safety of finished compost.
  • Ensure composting plants are placed as close to farmland as possible and do not adversely affect surrounding communities.
  • Take advantage of financial incentives such as subsidies or exemptions to set up centralized composting infrastructure, increase participation, and improve waste separation.
  • Partner with schools, community gardens, farms, nonprofits, women’s groups, and other community organizations to promote composting and teach the importance of waste separation.
  • Consider partnerships through initiatives such as sister cities to share innovation and develop capacity.
  • If additional infrastructure is needed, consider methane digesters as alternatives to composting.
  • Create, support, or join certification programs that verify the quality of compost and/or verify food waste suppliers such as hotels, restaurants, and cafes.

Further information:

Business Leaders
  • Establish zero-waste and OW diversion goals; incorporate the goals into corporate net-zero strategies.
  • Ensure procurement uses strategies to reduce FLW at all stages of the supply chain; consider using the Food Loss and Waste Protocol.
  • Ensure corporate procurement and facilities managers use local compost when possible.
  • Participate in consultations with farmers, policymakers, and the public to determine where to place plants, how to use compost, pricing, and how to roll out programs.
  • Work with farmers, local gardeners, the private sector, and local park systems to develop markets for compost.
  • Offer employee pre-tax benefits on materials to compost at home or participate in municipal composting programs.
  • Offer financial services, including low-interest loans, microfinancing, and grants, to support composting initiatives.
  • Support extended producer responsibility approaches that hold producers accountable for waste.
  • Educate employees on the benefits of composting, include them in companywide waste diversion initiatives, and encourage them to use and advocate for municipal composting in their communities. Clearly label containers and signage for composting.
  • Partner with schools, community gardens, farms, nonprofits, women’s groups, and other community organizations to promote composting and teach the importance of waste separation.
  • Create, support, or join certification programs that verify the quality of compost and/or verify food waste suppliers such as hotels, restaurants, and cafes.

Further information:

Nonprofit Leaders
  • Help policymakers establish zero-waste and OW diversion goals; help incorporate them into local or national climate plans.
  • Ensure organizational procurement uses local compost when possible.
  • Help administer, fund, or promote local composting programs.
  • Help gather data on local OW streams, potential markets, and comparisons of alternative uses such as methane digesters.
  • Participate in consultations with farmers, policymakers, businesses, and the public to determine where to place plants, how to use compost, pricing, and how to roll out programs.
  • Work with farmers, local gardeners, the private sector, and local park systems to develop markets for compost.
  • Help ensure low- and middle-income households are served by composting programs with particular attention to underserved communities such as multi-family buildings and rural households.
  • Advocate for extended producer responsibility approaches that hold producers accountable for waste.
  • Advocate for laws or regulations that require waste separation as close to the source as possible, ensuring the rules are effective and practical.
  • Create demonstration projects to show the effectiveness and safety of finished compost.
  • Establish one-stop-shop educational programs that use online and in-person methods to teach how to separate waste effectively and why that’s important.
  • Partner with schools, community gardens, farms, nonprofits, women’s groups, and other community organizations to promote composting and teach the importance of waste separation.
  • Create, support, or join certification programs that verify the quality of compost and/or verify food waste suppliers such as hotels, restaurants, and cafes.

Further information:

Investors
  • Ensure relevant portfolio companies separate waste streams, contribute to compost programs, and/or use finished compost.
  • Invest in companies developing composting programs or technologies that support the process, such as equipment, circular supply chains, and consumer products.
  • Fund start-ups or existing companies that are improving waste separation technology that enhances the quality of final compost products.
  • Offer financial services, including low-interest loans, microfinancing, and grants, to support composting initiatives.
  • Invest in companies that adhere to extended producer responsibility or encourage portfolio companies to adopt the policies.

Further information:

Philanthropists and International Aid Agencies
  • Help policymakers establish zero-waste and OW diversion goals; help incorporate them into local or national climate plans.
  • Advocate for businesses to establish time-bound and transparent zero-waste and OW diversion goals.
  • Advocate for extended producer responsibility approaches that hold producers accountable for waste.
  • Provide financing and capacity building for low- and middle-income countries to establish composting infrastructure and programs.
  • Help administer, fund, or promote composting programs.
  • Invest in companies developing composting programs or technologies that support the process, such as equipment, circular supply chains, and consumer products.
  • Fund startups or existing companies that are improving waste separation technology that enhances the quality of final compost products.
  • Incubate and fund mission-driven organizations and cooperatives that are advancing OW composting.
  • Offer financial services, including low-interest loans, microfinancing, and grants, to support composting initiatives.
  • Participate in consultations with farmers, policymakers, businesses, and the public to determine where to place plants, how to use compost, pricing, and how to roll out programs.
  • Work with farmers, local gardeners, the private sector, and local park systems to develop markets for compost.
  • Help ensure low- and middle-income households are served by composting programs, with particular attention to underserved communities such as multifamily buildings and rural households.
  • Advocate for laws or regulations that require waste separation as close to the source as possible, ensuring the rules are effective and practical.
  • Create demonstration projects to show the effectiveness and safety of finished compost.
  • Research and enact effective composting promotional strategies.
  • Establish one-stop-shop educational programs that use online and in-person methods to teach how to separate waste effectively and why that’s important.
  • Partner with schools, community gardens, farms, nonprofits, women’s groups, and other community organizations to promote composting and teach the importance of waste separation.
  • Create, support, or join certification programs that verify the quality of compost and/or verify food waste suppliers such as hotels, restaurants, and cafes.

Further information:

Thought Leaders
  • Participate in and promote centralized, community, or household composting programs, if available, and carefully sort OW from other waste streams.
  • If no centralized composting system exists, work with local experts to establish household and community composting systems.
  • Help policymakers establish zero-waste and OW diversion goals; help incorporate them into local or national climate plans.
  • Start cooperatives that provide services and/or equipment for composting.
  • Participate in consultations with farmers, policymakers, businesses, and the public to determine where to place plants, how to use compost, pricing, and how to roll out programs.
  • Help gather data on local OW streams, potential markets, and comparisons of alternative uses such as methane digesters.
  • Help develop waste separation technology that enhances the quality of final compost products and/or improve educational programs on waste separation.
  • Develop innovative governance models for local composting programs; publicly document your experiences.
  • Work with farmers, local gardeners, the private sector, and local park systems to develop markets for compost.
  • Advocate for extended producer responsibility approaches that hold producers accountable for waste.
  • Advocate for laws or regulations that require waste separation as close to the source as possible, ensuring the rules are effective and practical.
  • Create demonstration projects to show the effectiveness and safety of finished compost.
  • Create, support, or join certification programs that verify the quality of compost.
  • Research various governance models for local composting programs and outline options for communities to consider.
  • Research and enact effective composting campaign strategies.
  • Create, support, or join certification programs that verify the quality of compost and/or verify food waste suppliers such as hotels, restaurants, and cafes.

Further information:

Technologists and Researchers
  • Quantify estimates of OW both locally and globally; estimate the associated potential compost output.
  • Improve waste separation technology to improve the quality of finished compost.
  • Create tracking and monitoring software for OW streams, possible uses, markets, and pricing.
  • Research the application of AI and robotics for optimal uses of OW streams, separation, collection, distribution, and uses.
  • Research various governance models for local composting programs and outline options for communities to consider.
  • Research effective composting campaign strategies and how to encourage participation from individuals.

Further information:

Communities, Households, and Individuals
  • Participate in and promote centralized composting programs, if available, and carefully sort OW from other waste.
  • If no centralized composting system exists, work with local experts to establish household and community composting systems.
  • Participate in consultations with farmers, policymakers, and businesses to determine where to place plants, how to use compost, pricing, and how to roll out programs.
  • Take advantage of educational programs, financial incentives, employee benefits, and other programs that facilitate composting.
  • Advocate for extended producer responsibility approaches that hold producers accountable for waste.
  • Advocate for laws or regulations that require waste separation, ensuring the rules are effective and practical.
  • Partner with schools, community gardens, farms, nonprofits, women’s groups, and other community organizations to promote composting and teach the importance of waste separation.
  • Create, support, or join certification programs that verify the quality of compost and/or verify food waste suppliers such as hotels, restaurants, and cafes.

Further information:

Sources
Evidence Base

Consensus of effectiveness as a climate solution: High

Composting reduces OW, prevents pollution and GHG emissions from landfilled OW, and creates soil amendments that can reduce the use of synthetic fertilizers (Kaza et al., 2018; Manea et al., 2024). Although we do not quantify carbon sequestration from compost use in this analysis, a full life-cycle analysis that includes application could result in net negative emissions for composting (Morris et al., 2013).

Globally, the waste sector was responsible for an estimated 3.9% of total global GHG emissions in 2023, and solid waste management represented 36% of those emissions (IPCC, 2023; UNEP, 2024). Emissions estimates based on satellite and field measurements from landfills or direct measurements of carbon content in food waste can be significantly higher than IPCC Tier 1-based estimates. Reviews of global waste management estimated that food loss and food waste account for around 6% of global emissions or approximately 2.8 Gt CO₂‑eq/yr (Wilson et al., 2024; Zhu et al., 2023). Facility-scale composting reduces emissions 38–84% relative to landfilling (Perez et al., 2023), and monitoring and managing the moisture content, aeration, and carbon to nitrogen ratios can further reduce emissions (Ayilara et al., 2020).

Unclear legislation and regulation for MSW composting can prevent adoption, and there is not a one-size-fits-all approach to composting (Cao et al., 2023). Regardless of the method used, composting converts OW into a nutrient-rich resource and typically reduces incoming waste volumes 40–60% in the process (Cao et al., 2023; Kaza et al., 2018). A comparative cost and energy analysis of MSW components highlighted that while composting adoption varies geographically and economically, environmental benefits also depend on geography and income (Zaman, 2016). Food and green waste percentages of MSW are higher in lower-resourced countries than in high-income countries due to less packaging, and more than one-third of waste in high-income countries is recovered through recycling and composting (Kaza et al., 2018).

The results presented in this document summarize findings from 22 reports, 31 reviews, 12 original studies, two books, nine web articles, one fact sheet, and three data sets reflecting the most recent evidence for more than 200 countries and territories. 

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Appendix

Global MSW Generation and Disposal

Analysis of MSW in this section is based on the 2018 What a Waste 2.0 global dataset and report as well as the references cited in the report (Kaza et al., 2018; World Bank 2018). In 2018, approximately 2 Gt of waste was generated globally. Most of that went to landfills (41%) and open dumps (22%). Out of 217 countries and territories, 24 sent more than 80% of all MSW to landfills and 3 countries reported landfilling 100% of MSW. The average across all countries/territories was 28% of MSW disposed of in landfills. Both controlled and sanitary landfills with gas capture systems are included in the total landfilled percentage.

Approximately 13% of MSW was treated through recycling and 13% through incineration, but slightly more waste was incinerated than recycled per year. Incineration was predominately used in upper-middle and high-income countries with negligible amounts of waste incinerated in low- and lower-middle income countries.

Globally, only about 5% of MSW was composted and nearly no MSW was processed via methane digestion. However, OW made up nearly 40% of global MSW, so most OW was processed through landfilling, open dumping, and incineration all of which result in significant GHG emissions and pollution. There is ample opportunity to divert more OW from polluting disposal methods toward composting. Due to lack of data on open dumping, and since incineration only accounts for 1% of global GHG emissions, we chose landfilling as our baseline disposal method for comparison.

In addition to MSW, other waste streams include medical waste, e-waste, hazardous waste, and agricultural waste. Global agricultural waste generation in 2018 was more than double total MSW (Kaza et al., 2018). Although these specialized waste streams are treated separately from MSW, integrated waste management systems with high-quality source separation programs could supplement organic MSW with agricultural waste. Rather than being burned or composted on-farm, agricultural waste can provide bulking materials that are critical for maintaining moisture levels and nutrient balance in the compost pile, as well as scaling up composting operations. 

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Details of a Composting System and Process

Successful centralized composting starts with collection and separation of OW from other waste streams, ideally at the source of waste generation. Financial and regulatory barriers can hinder creation or expansion of composting infrastructure. Composting systems require both facilities and robust collection networks to properly separate OW from nonbiodegradable MSW and transport OW to facilities. Mixed waste streams increase contamination risks with incoming feedstocks, so separation of waste materials at the source of generation is ideal. 

Establishing OW collection presents a financial and logistical barrier to increased composting adoption (Kawai et al., 2020; Kaza et al., 2018). However, when considering a full cost-chain analysis that includes collection, transportation, and treatment, systems that rely on source-separated OW can be more cost-effective than facilities that process mixed organics. 

OW and inorganic waste can also be sorted at facilities manually or mechanically with automated techniques including electromagnetic separation, ferrous metal separation, and sieving or screening (Kawai et al., 2020). Although separation can be highly labor-intensive, it’s necessary to remove potential contaminants, such as plastics, heavy metals, glass, and other nonbiodegradable or hazardous waste components (Kawai et al., 2020; Manea et al., 2024). After removing contaminants, organic materials are pre-processed and mixed to achieve the appropriate combination of water, oxygen, and solids for optimal aerobic conditions during the composting process. 

Regardless of the specific composting method used, aerobic decomposition is achieved by monitoring and balancing key parameters within the compost pile. Key parameters are moisture content, temperature, carbon-to-nitrogen ratio, aeration, pH, and porosity (Cao et al., 2023; Kawai et al., 2020; Manea et al., 2024). The aerobic decomposition process can be split into distinct stages based on whether mesophilic (active at 20–40 oC) or thermophilic (active at 40–70 oC) bacteria and fungi dominate. Compost piles are constructed to allow for sufficient aeration while optimizing moisture content (50–60%) and the initial carbon-to-nitrogen ratio (25:1–40:1), depending on composting method and feedstocks (Amuah et al., 2022; Manea et al, 2024). Optimal carbon-to-nitrogen ratios are achieved through appropriate mixing of carbon-rich “brown” materials, such as sawdust or dry leaves, with nitrogen-rich “green” materials, such as food waste or manure (Manea et al., 2024). During the thermophilic stage, temperatures exceeding 62 oC are necessary to kill most pathogens and weed seeds (Amuah et al., 2022; Ayilara et al., 2020).

Throughout the composting process key nutrients (nitrogen, phosphorus, potassium, calcium, magnesium, and sodium), are mineralized and mobilized and microorganisms release GHGs and heat as by-products of their activity (Manea et al., 2024; Nordahl et al., 2023). Water is added iteratively to maintain moisture content and temperature in the optimal ranges, and frequent turning and aeration are necessary to ensure microorganisms have enough oxygen. Without the proper balance of oxygen and water, anaerobic conditions can lead to higher methane emissions (Amuah et al., 2022; Manea et al., 2024). Although CO₂, methane, and nitrous oxide are released during the process, these emissions are significantly lower than associated emissions from landfilling (Ayilara et al., 2020; Cao et al., 2023; FAO, 2019; Perez et al., 2023).

Once aerobic decomposition is completed, compost goes through a maturation stage where nutrients are stabilized before finished compost can be sold or used as a soil amendment. In stable compost, microbial decomposition slows until nutrients no longer break down, but can be absorbed by plants. Longer maturation phases reduce the proportion of soluble nutrients that could potentially leach into soils. 

The baseline waste management method of landfilling OW is cheaper than composting; however it also leads to significant annual GHG emissions. Composting, although more expensive due to higher labor and operating costs, reduces emissions and produces a valuable soil amendment. Establishing a composting program can have significant financial risks without an existing market for finished compost products (Bogner et al., 2007; Kawai et al., 2020; UNEP, 2024).

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Example Calculation of Achievable Adoption

In 2018, Austria had the highest composting rate of 31.2%, and Vietnam composted 15% of MSW (World Bank, 2018). 

For low adoption, we assumed composting increases by 25% of the existing rate or until all OW in MSW is composted. In Austria, OW made up 31.4% of MSW in 2018, so the Adoption – Low composting rate was 31.4%. In Vietnam, the Adoption – Low composting rate came out to 18.75%, which is still less than the total OW percentage of MSW (61.9%).

For high adoption, we assumed that composting rates increase by 50% of the existing rate or until all OW in MSW is composted. So high adoption in Austria remains 31.4% (i.e., all OW generated in Austria is composted). In Vietnam, the high adoption composting rate increases to 22.5% but still doesn’t capture all OW generated (61.9% of MSW).

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Updated Date

Deploy Alternative Insulation Materials

Submitted by Drawdown Admin on
Sector
Industry, Materials & Waste
Mode
Cut Emissions
Cluster
Improve Materials
Image
Worker sprays insulation in building frame.
Coming Soon
Off
Summary

Deploy Alternative Insulation Materials is defined as using alternative building insulation materials in place of conventional ones. In particular, we highlight the impact of using cellulose instead of glass, mineral, or plastic insulation in new and retrofit buildings. Cellulose insulation manufacture and installation emits fewer GHGs to reach the same operational insulating performance than does manufacture and installation of conventional materials.

Income & work,Health
Water resources
Description for Social and Search
Deploy Alternative Insulation Materials is a Highly Recommended climate solution. It reduces GHGs emitted during insulation manufacturing and installation.
Overview

Thermal insulation materials are used in the walls, roofs, and floors of buildings to help maintain comfortable indoor temperatures. However, manufacture and installation of insulation materials produces GHG emissions. These are called embodied emissions because they occur before the insulation is used in buildings. Insulation embodied emissions offset a portion of the positive climate impacts from using insulation to reduce heating and cooling demand. A Canadian study found that over 25% of residential embodied emissions from manufacturing building materials can be due to insulation (Magwood et al., 2022). Using cellulose insulation made primarily from recycled paper avoids some embodied emissions associated with conventional insulation.

Insulation is manufactured in many different forms, including continuous blankets or boards, loose fill, and sprayed foam (Types of Insulation, n.d.). Most conventional insulation materials are nonrenewable inorganic materials such as stone wool and fiberglass. These require high temperatures (>1,300 °C) to melt the raw ingredients, consuming thermal energy and releasing CO₂ from fossil fuel combustion or grid power generation (Schiavoni et al., 2016). Other common insulations are plastics, including expanded polystyrene (EPS), extruded polystyrene (XPS), polyurethane (PUR), and polyisocyanurate (PIR). Producing these plastics requires the extraction of fossil fuels – primarily petroleum – for feedstocks, as well as high amounts of energy for processing (Harvey, 2007). 

F-gases are often used as blowing agents to manufacture rigid foam board insulation or install sprayed foam insulation. F-gases are GHGs with GWPs that can be hundreds or thousands of times higher than CO₂. High-GWP F-gases used in foam production are released into the atmosphere during all subsequent stages of the foam’s life cycle (Biswas et al., 2016; Waldman et al., 2023). The climate benefits of this solution during the installation stage are primarily due to avoiding these blowing agents. 

Alternative insulation is produced from plant or animal biomass (bio-based materials) or waste products (recycled materials). Alternative insulation materials provide climate benefits by consuming less manufacturing energy, using renewable materials in place of fossil fuels, and eliminating high-GWP blowing agents (Sustainable Traditional Buildings Alliance, 2024). 

Figure 1 compares a variety of conventional and alternative insulation materials. While many bio-based and recycled materials could be used as alternatives to these conventional materials, this solution focuses on cellulose due to its effectiveness in avoiding emissions, low cost, and wide availability. Cellulose insulation is made primarily from recycled paper fibers, newsprint, and cardboard. These products are made into fibers and blended with fire retardants to produce loose or batt cellulose insulation (Waldman et al., 2023; Wilson, 2021).

Figure 1. Properties and adoption of conventional and alternative insulation materials. Costs and emissions will vary from the values here depending on the insulation form (board, blanket, loose-fill, etc.).

Category Material High-GWP F-gases used? Median manufacturing and installation emissions* Mean product and installation cost** Estimated market share
(% by mass)
Conventional materials Stone wool No 0.31 623 20
Glass wool (fiberglass) No 0.29 508 34
EPS No 0.38 678 22
XPS Yes, sometimes 9.44 702 7
PUR/PIR Yes, sometimes 6.14 1,000 11
Alternative materials Cellulose No 0.05 441 2–13
Cork No 0.30 1,520 Commercially available, not widely used
Wood fiber No 0.13 814 Commercially available, not widely used
Plant fibers (kenaf, hemp, jute) No 0.18 467 Commercially available, not widely used
Sheep’s wool No 0.14 800 Commercially available, not widely used
Recycled PET plastic No 0.12 2,950 Commercially available, not widely used

*t CO₂‑eq (100-yr) to insulate 100m² to 1m²·K/W

**2023 US$ to insulate 100m² to 1m²·K/W. We use mean values for cost analysis to better capture the limited data and wide range of reported costs.

Although we are estimating the impact of using cellulose insulation in all buildings, the unique circumstances of each building are important when choosing the most appropriate insulation material. In this solution, we do not distinguish between residential and commercial buildings, retrofit or new construction, different building codes, or different climates, but these would be important areas of future study.

In this solution, the effectiveness, cost, and adoption are calculated over a specified area (100 m²) and thermal resistance (1 m²·K/W). The chosen adoption unit ensures that all data are for materials with the same insulating performance. Due to limited material information, we assumed that insulation mass scales linearly with thermal resistance.

To better understand the adoption unit, a one-story residential building of 130 m² floor area would require approximately 370 m² of insulation area (RSMeans, & The Gordian Group, 2023). For a cold climate like Helsinki, Finland, code requires insulation thermal resistance of 11 m²·K/W (The World Bank Group, n.d.). For a warm climate like Jerusalem, Israel, envelope thermal resistance requirements average 1.1 m²·K/W (The World Bank Group, n.d.). Therefore, depending on the location, anywhere from approximately 4–40 adoption units insulating 100 m² to 1 m²·K/W may be needed to insulate a small single-story home to the appropriate area and insulation level.

Take Action Intro

Would you like to help deploy alternative insulation? Below are some ways you can make a difference, depending on the roles you play in your professional or personal life.

These actions are meant to be starting points for involvement and may or may not be the most important, impactful, or doable actions you can take. We encourage you to explore, get creative, and take a step that is right for you!

Adams, M., Burrows, V., & Richardson, S. (2019). Bringing embodied carbon upfront: Coordinated action for the building and construction sector to tackle embodied carbon. World Green Building Council, Advancing Net Zero, Ramboll, & C40 Cities. Link to source: https://worldgbc.s3.eu-west-2.amazonaws.com/wp-content/uploads/2022/09/22123951/WorldGBC_Bringing_Embodied_Carbon_Upfront.pdf 

Amendment to the Montreal Protocol on substances that deplete the ozone layer. (2016, October 15). Link to source: https://treaties.un.org/doc/Treaties/2016/10/20161015%2003-23%20PM/Ch_XXVII-2.f-English%20and%20French.pdf 

Andersen, B., & Rasmussen, T. V. (2025). Biobased building materials: Moisture characteristics and fungal susceptibility. Building and Environment, 112720. Link to source: https://doi.org/10.1016/j.buildenv.2025.112720 

Asdrubali, F., D’Alessandro, F., & Schiavoni, S. (2015). A review of unconventional sustainable building insulation materials. Sustainable Materials and Technologies, 4, 1–17. Link to source: https://doi.org/10.1016/j.susmat.2015.05.002 

Biswas, K., Shrestha, S. S., Bhandari, M. S., & Desjarlais, A. O. (2016). Insulation materials for commercial buildings in North America: An assessment of lifetime energy and environmental impacts. Energy and Buildings, 112, 256–269. Link to source: https://doi.org/10.1016/j.enbuild.2015.12.013 

Cabeza, L. F., Boquera, L., Chàfer, M., & Vérez, D. (2021). Embodied energy and embodied carbon of structural building materials: Worldwide progress and barriers through literature map analysis. Energy and Buildings, 231, 110612. Link to source: https://doi.org/10.1016/j.enbuild.2020.110612 

Carbon Removals Expert Group Technical Assistance. (2023, December). Review of certification methodologies for long-term biogenic carbon storage in buildings. European Commission. Link to source: https://climate.ec.europa.eu/system/files/2023-12/policy_carbon_expert_biogenic_carbon_storage_in_buildings_en.pdf 

Deer et al. (2007). Alaska Residential Building Manual. Alaska Housing Finance Corporation. Link to source: https://www.ahfc.us/application/files/2813/5716/1325/building_manual.pdf 

Esau et al. (2021). Reducing Embodied Carbon in Buildings: Low-Cost, High-Value Opportunities. RMI. Link to source: http://www.rmi.org/insight/reducing-embodied-carbon-in-buildings 

The Freedonia Group. (2024). Global insulation report. Link to source: https://www.freedoniagroup.com/industry-study/global-insulation 

Fabbri, M., Rapf, O., Kockat, J., Fernández Álvarez, X., Jankovic, I., & Sibileau, H. (2022). Putting a stop to energy waste: How building insulation can reduce fossil fuel imports and boost EU energy security. Buildings Performance Institute Europe. Link to source: https://www.bpie.eu/wp-content/uploads/2022/05/Putting-a-stop-to-energy-waste_Final.pdf 

Forestry production and trade. (2023). [Dataset]. FAOSTAT. Link to source: https://www.fao.org/faostat/en/#data/FO 

Füchsl, S., Rheude, F., & Röder, H. (2022). Life cycle assessment (LCA) of thermal insulation materials: A critical review. Cleaner Materials, 5, 100119. Link to source: https://doi.org/10.1016/j.clema.2022.100119 

Gelowitz, M. D. C., & McArthur, J. J. (2017). Comparison of type III environmental product declarations for construction products: Material sourcing and harmonization evaluation. Journal of Cleaner Production, 157, 125–133. Link to source: https://doi.org/10.1016/j.jclepro.2017.04.133 

Global Alliance for Buildings and Construction, International Energy Agency, and the United Nations Environment Programme. (2020). GlobalABC roadmap for buildings and construction: Towards a zero-emission, efficient and resilient buildings and construction sector. International Energy Agency. Link to source: https://www.iea.org/reports/globalabc-roadmap-for-buildings-and-construction-2020-2050 

Grazieschi, G., Asdrubali, F., & Thomas, G. (2021). Embodied energy and carbon of building insulating materials: A critical review. Cleaner Environmental Systems, 2, 100032. Link to source: https://doi.org/10.1016/j.cesys.2021.100032 

Harvey, L. D. D. (2007). Net climatic impact of solid foam insulation produced with halocarbon and non-halocarbon blowing agents. Building and Environment, 42(8), 2860–2879. Link to source: https://doi.org/10.1016/j.buildenv.2006.10.028 

Insulation choices revealed in new study. (2019, June 19). Home Innovation Research Labs. Link to source: https://www.homeinnovation.com/trends_and_reports/trends/insulation_choices_revealed_in_new_study 

International Energy Agency. (2023). Building envelopes. Link to source: https://www.iea.org/energy-system/buildings/building-envelopes 

International Energy Agency, International Renewable Energy Agency, & United Nations Climate Change High-Level Champions. (2023). Breakthrough agenda report 2023. Link to source: https://www.iea.org/reports/breakthrough-agenda-report-2023 

Jelle, B. P. (2011). Traditional, state-of-the-art and future thermal building insulation materials and solutions – Properties, requirements and possibilities. Energy and Buildings, 43(10), 2549–2563. Link to source: https://doi.org/10.1016/j.enbuild.2011.05.015 

Kumar, D., Alam, M., Zou, P. X. W., Sanjayan, J. G., & Memon, R. A. (2020). Comparative analysis of building insulation material properties and performance. Renewable and Sustainable Energy Reviews, 131, 110038. Link to source: https://doi.org/10.1016/j.rser.2020.110038 

Magwood et al. (2022). Emissions of materials benchmark assessment for residential construction report. Passive Buildings Canada and Builders for Climate Action.

Malhotra, A., & Schmidt, T. S. (2020). Accelerating Low-Carbon Innovation. Joule, 4(11), 2259–2267. Link to source: https://doi.org/10.1016/j.joule.2020.09.004 

Mályusz, L., & Pém, A. (2013). Prediction of the learning curve in roof insulation. Automation in Construction, 36, 191–195. Link to source: https://doi.org/10.1016/j.autcon.2013.04.004 

Maskell, D., Da Silva, C., Mower, K., Rana, C., Dengel, A., Ball, R., Ansell, M., Walker, P., & Shea, A. (2015, June 22). Properties of bio-based insulation materials and their potential impact on indoor air quality. First International Conference on Bio-based Building Materials, Clermont-Ferrand, France.

McGrath et al. (2023). Embodied carbon and material health in insulation. Healthy Building Network, Perkins&Will. Link to source: https://habitablefuture.org/wp-content/uploads/2024/03/96-Carbon-Health-Insulation.pdf 

Naldzhiev, D., Mumovic, D., & Strlic, M. (2020). Polyurethane insulation and household products: A systematic review of their impact on indoor environmental quality. Building and Environment, 169, 106559. Link to source: https://doi.org/10.1016/j.buildenv.2019.106559 

Northeast Bio-based Materials Collective 2023 summit proceedings. (2023). Link to source: https://massdesigngroup.org/sites/default/files/file/2024/Northeast%20Bio-Based%20Materials%20Collective%202023%20Summit%20Proceedings.pdf 

Petcu et al. (2023). Research on thermal insulation performance and impact on indoor air quality of cellulose-based thermal insulation materials. Materials, 16(15), Article 15. Link to source: https://doi.org/10.3390/ma16155458 

Rabbat, C., Awad, S., Villot, A., Rollet, D., & Andrès, Y. (2022). Sustainability of biomass-based insulation materials in buildings: Current status in France, end-of-life projections and energy recovery potentials. Renewable and Sustainable Energy Reviews, 156, 111962. Link to source: https://doi.org/10.1016/j.rser.2021.111962 

Riverse. (2024, August). Methodology: Biobased construction materials. Link to source: https://www.riverse.io/methodologies/biobased-construction-materials 

RSMeans, & The Gordian Group. (2023, September). Installed cost of residential siding comparative study – September 2023 [Report]. The Brick Industry Association. Link to source: https://www.gobrick.com/content/userfiles/files/RSMeans%20Residential%20Siding%20Comparative%20Cost%20Wall%20System%20Study%20Final%202023-09-15.pdf

SaravanaPrabhu et al. (2021). Comparative analysis of learning curve models on construction productivity of diaphragm wall and pile. IOP Conference Series: Materials Science and Engineering, 1197(1), 012004. Link to source: https://doi.org/10.1088/1757-899X/1197/1/012004 

Schiavoni, S., D׳Alessandro, F., Bianchi, F., & Asdrubali, F. (2016). Insulation materials for the building sector: A review and comparative analysis. Renewable and Sustainable Energy Reviews, 62, 988–1011. Link to source: https://doi.org/10.1016/j.rser.2016.05.045 

Schulte, M., Lewandowski, I., Pude, R., & Wagner, M. (2021). Comparative life cycle assessment of bio-based insulation materials: Environmental and economic performances. GCB Bioenergy, 13(6), 979–998. Link to source: https://doi.org/10.1111/gcbb.12825 

Searchinger, T., Peng, L., Zionts, J., & Waite, R. (2024). The global land squeeze: Managing the growing competition for land. World Resources Institute. Link to source: https://www.wri.org/research/global-land-squeeze-managing-growing-competition-land

Stamm et al. (2022). Chemical and environmental justice impacts in the life cycle of building insulation. Energy Efficiency for All, Healthy Building Network. Link to source: https://informed.habitablefuture.org/resources/research/20-chemical-and-environmental-justice-impacts-in-the-life-cycle-of-building-insulation-report-brief 

Sustainable Traditional Buildings Alliance. (2024, March). The use of natural insulation materials in retrofit. Link to source: https://stbauk.org/wp-content/uploads/2024/03/The-use-of-natural-insulation-materials-in-retrofit.pdf 

The World Bank Group. (n.d.). Mapping energy efficiency: A global dataset on building code effectiveness and compliance: Country profiles. Link to source: https://www.worldbank.org/content/dam/sites/buildinggreen/doc/building_green_country_profile.pdf

Types of insulation. (n.d.). U.S. Department of Energy. Link to source: https://www.energy.gov/energysaver/types-insulation 

Waldman et al. (2023). 2023 Carbon Leadership Forum North American material baselines. Carbon Leadership Forum, University of Washington. Link to source: https://carbonleadershipforum.org/clf-material-baselines-2023/ 

Wang et al. (2023). Can paper waste be utilised as an insulation material in response to the current crisis. Sustainability, 15(22), Article 22. Link to source: https://doi.org/10.3390/su152215939 

Wi, S., Kang, Y., Yang, S., Kim, Y. U., & Kim, S. (2021). Hazard evaluation of indoor environment based on long-term pollutant emission characteristics of building insulation materials: An empirical study. Environmental Pollution, 285, 117223. Link to source: https://doi.org/10.1016/j.envpol.2021.117223 

Wilson. (2021). The BuildingGreen guide to thermal insulation: What you need to know about performance, health, and environmental considerations. BuildingGreen, Inc.

Zabalza Bribián, I., Valero Capilla, A., & Aranda Usón, A. (2011). Life cycle assessment of building materials: Comparative analysis of energy and environmental impacts and evaluation of the eco-efficiency improvement potential. Building and Environment, 46(5), 1133–1140. Link to source: https://doi.org/10.1016/j.buildenv.2010.12.002 

Credits

Lead Fellow

  • Sarah Gleeson, Ph.D.

Contributors

  • Ruthie Burrows, Ph.D.

  • James Gerber, Ph.D.

  • Yusuf Jameel, Ph.D. 

  • Daniel Jasper

  • Alex Sweeney

Internal Reviewers

  • Aiyana Bodi

  • Hannah Henkin

  • Ted Otte

  • Amanda D. Smith, Ph.D.

  • Christina Swanson, Ph.D.

Effectiveness

To insulate 100 m² to a thermal resistance of 1 m²·K/W using entirely cellulose insulation in place of the current baseline mix of insulation materials is expected to avoid 1.59 t CO₂‑eq on a 100-yr basis (Table 1). Since many of the avoided emissions are F-gases, the 20-yr effectiveness is higher, avoiding 4.07 t CO₂‑eq per unit of insulation. Effectiveness for this solution measures the one-time reduced emissions from manufacturing and installing insulation. Insulation also reduces the energy used while a building is operating, but those emissions are addressed separately in the Improve Building Envelopes solution. 

Conventional insulation effectiveness was considered to be a weighted average effectiveness of the current baseline insulation mix, including a small amount of cellulose insulation currently in use.

The largest contributor to conventional insulation embodied emissions is using high-GWP blowing agents to manufacture or install XPS, PUR, or PIR foam. We assumed the use of F-gas blowing agents for all foams, although these are already being regulated out of use globally (Amendment to the Montreal Protocol on Substances That Deplete the Ozone Layer, 2016) and an unknown amount of low-GWP blowing agents are currently used (such as hydrocarbons or CO₂). Therefore, we anticipate the effectiveness of this solution will decrease as F-gases are used less in the future. We assumed that 100% of blowing agents are emitted over the product lifetime.

Cellulose has the greatest avoided emissions of all of the alternative materials we evaluated (Figure 1). The next most effective materials were recycled PET, wood fibers, and sheep’s wool. Conventional materials like XPS, PUR, and PIR that are foamed with F-gases had the highest GHG emissions. For bio-based materials, we did not consider biogenic carbon as a source of carbon sequestration due to quantification and permanence concerns. 

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Table 1. Effectiveness at reducing emissions.

Unit: t CO₂‑eq /insulation required to insulate 100 m² to a thermal resistance of 1 m²·K/W, 100-yr basis

25th percentile 0.98
Mean 1.34
Median (50th percentile) 1.59
75th percentile 1.81
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Cost

Available cost data are variable for all materials, particularly those in early-stage commercialization. The mean cost of purchasing and installing cellulose insulation is less than that of any other conventional or alternative insulation material (Figure 1). Compared with the average cost of conventional insulation, the mean cost savings for cellulose insulation is US$193/100 m² insulated to a thermal resistance of 1 m²·K/W. Since most buildings are insulated over greater areas to higher thermal resistances, these savings would quickly add up. When considering the mean cost per median climate impact, cellulose insulation saves US$121/t CO₂‑eq (100-yr basis), making it an economically and environmentally beneficial alternative (Table 2).

We considered conventional insulation cost to be a weighted average cost of the current baseline insulation mix, including a small amount of cellulose insulation currently in use.

For conventional insulation, material costs of purchasing the insulation are higher than costs for installation (US$540 and US$97, respectively, to insulate 100 m2 to a thermal resistance of 1 m²·K/W). Cellulose has a lower product cost and comparable installation costs to conventional materials. We considered all costs to be up front and not spread over the lifetime of the material or building. For each material type, cost will vary based on the form of the insulation (board, loose, etc.), and this should be accounted for when comparing insulation options for a particular building. 

We determined net costs of insulation materials by adding the mean cost to purchase the product and the best estimation of installation costs based on available information. Installation costs were challenging to find data on and therefore represent broad assumptions of installation type and labor. Cost savings were determined by subtracting the weighted average net cost of conventional materials to the net cost of an alternative material. Although we used median values for other sections of this assessment, the spread of data was large for product cost estimates and the mean value was more appropriate in the expert judgment of our reviewers. 

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Table 2. Cost per unit of climate impact.

Unit: 2023 US$/t CO₂‑eq, 100-yr basis

Estimate -121
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Learning Curve

Little information is available about the learning rate for new insulation materials. Mályusz and Pém (2013) evaluated how labor time decreased with repetitive cycles for installing roof insulation. They found a learning rate of ~90%, but only for this specific insulation scenario, location, and material. Additionally, this study does not include any product or manufacturing costs that may decrease with scale.

In general, labor time for construction projects decreases with repetitive installation, including improved equipment and techniques and increased construction crew familiarity with the process (SaravanaPrabhu & Vidjeapriya, 2021). However, Malhotra and Schmidt (2020) classify building envelope retrofits as technologies that are highly customized based on user requirements, regulations, physical conditions, and building designs, likely leading to learning rates that are slow globally but where local expertise could reduce installation costs.

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Speed of Action

Speed of action refers to how quickly a climate solution physically affects the atmosphere after it is deployed. This is different from speed of deployment, which is the pace at which solutions are adopted.

At Project Drawdown, we define the speed of action for each climate solution as emergency brake, gradual, or delayed.

Deploy Alternative Insulation Materials is an EMERGENCY BRAKE climate solution. It has the potential to deliver a more rapid impact than gradual and delayed solutions. Because emergency brake solutions can deliver their climate benefits quickly, they can help accelerate our efforts to address dangerous levels of climate change. For this reason, they are a high priority.

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Caveats

Manufacturing and installation emissions reductions due to the use of alternative building thermal insulation materials are both permanent and additional. 

Permanence

There is a low risk of the emissions reductions for this solution being reversed. By using cellulose insulation instead of inorganic or plastic-based insulation, a portion of the manufacturing and installation emissions are never generated in the first place, making this a permanent reduction. Emissions from high-temperature manufacturing, petroleum extraction, and blowing agent use are all reduced through this approach.

Additionality

The GHG emissions reductions from alternative insulation materials are additional because we calculated them relative to a baseline insulation case. This includes a small amount of cellulose materials included in baseline building insulation. Therefore, avoided emissions represent an improvement of the current emissions baseline that would have occurred in the absence of this solution. 

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Current Adoption

Adoption data are extremely limited for alternative insulation materials. All adoption data and estimates are assumed to apply to both residential and commercial buildings, although in reality the uptake of alternative insulation materials will vary by building type due to differences in structures, climate, use type, and regulations. We assume that future uptake of alternative insulation is used only during retrofit or new construction, or when existing insulation is at the end of its functional lifetime.

European sources report that 2–13% of the insulation market is alternative materials. Depending on the source, this could include renewable materials, bio-based insulation, or recycled materials. In 2018 in the United States, 5% of total insulation area in new single-family homes was insulated with cellulose (Insulation Choices Revealed in New Study, 2019).

To convert estimated cellulose adoption percentage into annual insulation use, we estimated 26 Mt of all installed global insulation materials in 2023 based on a report from The Freedonia Group (2024). We calculated an annual use of approximately 1.7 billion insulation units of 100 m² at a thermal resistance of 1 m²·K/W. Therefore, the median cellulose adoption is 14 million units/yr at 100 m² at 1 m²·K/W, calculated from the median of the 2–13% adoption range. 

Since this calculation is based on more alternative materials than just cellulose and is heavily reliant on European data where we assume adoption is higher, this estimate of current adoption (Table 3) is most likely an overestimate.

The little adoption data that were considered in this section are mostly for Europe, and some for the United States. We recognize this limited geographic scope creates bias, and hope this work inspires research and data sharing on this topic in underrepresented regions.

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Table 3. Current (2017–2022) adoption level.

Unit: units of insulation/yr installed to insulate 100 m² to a thermal resistance of 1 m²·K/W

25th percentile 9000000
Mean 13000000
Median (50th percentile) 14000000
75th percentile 17000000
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Adoption Trend

Very few data are available that quantify adoption trends. In a regional study of several bio-based insulation materials, Rabbat et al. (2022) estimated French market annual growth rates of 4–10%, with cellulose estimated at 10%. Petcu et al. (2023) estimated the European adoption of recycled plastic and textile insulation, biomass fiber insulation, and waste-based insulation to have increased from 6% to 10% between 2012 and 2020.

When accounting for the calculated current adoption, these growth rates mean a median estimated annual increase of 500,000 insulation units/yr required to insulate 100 m² to a thermal resistance of 1 m²·K/W. The increasing adoption of bio-based insulation decreases the use of conventional insulation materials in those regions.

This adoption trend (Table 4) is likely an overestimate, as it is biased by high European market numbers and based on the likely high estimate we made for current adoption. 

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Table 4. 2012–2020 adoption trend.

Unit: annual change in units of insulation/yr installed to insulate 100 m² to a thermal resistance of 1 m²·K/W

25th percentile 500000
Mean 800000
Median (50th percentile) 500000
75th percentile 1300000
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Adoption Ceiling

No estimates have been found for the adoption ceiling of this solution, although we expect it to be high given low rates of current adoption and projected increases in building construction in the coming decades (International Energy Agency [IEA], International Renewable Energy Agency, & United Nations Climate Change High-Level Champions, 2023). Two physical factors that could influence adoption are availability of alternative materials and thickness of insulation.

For cellulose insulation, availability does not seem to limit adoption. The Food and Agriculture Organization of the United Nations (2023) reports that there is a much higher annual production of cellulose-based materials (>300 Mt annually of cartonboard, newsprint, and recycled paper) than the overall demand for insulation globally (>25 Mt annual demand; Global Insulation Report, 2024). However, other uses for cellulose products may create competition for this supply.

Increased thickness of insulation could also be a limiting factor because this would reduce adoption by decreasing building square footage, in particular making retrofits more challenging and expensive. Deer et al. (2007) reported that the average cellulose thermal resistance is similar to mineral and glass wool, and lower than plastic insulations made of polystyrene and other foams. If we assume that 50% of plastic insulation cannot be replaced with cellulose due to thickness limitations, this would represent ~20% of current insulation that could not be replaced without structural changes to the building. Therefore, we calculated the adoption ceiling to be 80% of the current insulation that would be reasonably replaceable, or 140 million units/yr required to insulate 100 m² to a thermal resistance of 1 m²·K/W (Table 5).

Uptake of cellulose insulation could also be limited by its susceptibility to absorbing moisture, limiting its use in wet climates or structures that retain moisture, such as flat roofs. Commercialization of alternative insulation materials beyond cellulose and in many different forms (e.g., board, loose-fill) will increase the adoption ceiling across more building types.

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Table 5. Adoption ceiling.

Unit: units of insulation/yr installed to insulate 100 m² to a thermal resistance of 1 m²·K/W

25th percentile N/A
Mean N/A
Estimate 140000000
75th percentile N/A
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Achievable Adoption

We found no estimates for feasible global adoption of this solution. Rabbat et al. (2022) estimated the adoption levels of several bio-based insulation materials in France in 2050. For cellulose wadding, this was estimated to be 2.1 times the commercialized volume in France in 2020. Although we do not expect France to be representative of the rest of the world, if the predicted adoption trend holds across the world then we expect low adoption in 2050 to be 2.1 times greater than 2023 adoption. This is 29 million units/yr to insulate 100 m² to a thermal resistance of 1 m²·K/W (Table 6).

The IEA (2023) claims that building envelopes need to have their retrofit rate increase by 2.5 times over the current rate in order to meet net zero targets (2023). This is a reasonable high-adoption scenario. Assuming that more retrofits of buildings occur and greater amounts of alternative insulation are installed in new buildings, we estimate that high future adoption of new insulation could occur at 2.5 times the rate of the low-adoption scenario. This is 73 million units/yr to insulate 100 m² to a thermal resistance of 1 m²·K/W (Table 6).

Adoption will be facilitated or limited by local regulations around the world. Building codes will determine the location and extent of use of cellulose or other bio-based insulation. We expect uptake to be different between residential and commercial buildings, but due to insufficient data, we have grouped them in our adoption estimates.

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Table 6. Range of achievable adoption levels.

Unit: units of insulation/yr installed to insulate 100 m² to a thermal resistance of 1 m²·K/W

Current adoption 14000000
Achievable – low 29000000
Achievable – high 73000000
Adoption ceiling 140000000
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The climate impacts for this solution are modest compared to current global GHG emissions. Not all conventional insulations have a high environmental impact due to the use of a wide range of materials, forms, and installation methods as well as the recent adoption of lower-GWP blowing agents. Therefore, the potential for further emissions savings is limited.

We quantified the effectiveness and adoption of cellulose insulation, which has the lowest emissions and, therefore, the highest climate impacts of the insulation materials we evaluated. With high adoption, 1.2 Gt CO₂‑eq on a 100-yr basis could be avoided over the next decade (Table 7).

While we only considered the adoption of cellulose insulation in this analysis, a realistic future for lowering the climate impact of insulation may include other bio-based materials, too. Utilizing a greater range of materials should increase adoption and climate impact due to more available forms, sources, and thermal resistance values of bio-based insulation.

Producing and deploying cellulose and other bio-based insulation requires the use of biomass as a feedstock. Multiple climate solutions, in addition to alternative insulation materials, require biomass, and projected demand across solutions greatly exceeds supply. The deforestation that would be required to meet demand would produce emissions far greater than any mitigation gains from full deployment of these solutions (Searchinger, 2024). In addition to deforestation, there would also be costs and emissions incurred to transport biomass from where it is produced to where it can be processed and used. Thus, the achievable climate impacts presented here is only possible if feedstocks are prioritized for this solution. If feedstocks are instead prioritized for other climate solutions (see Interactions for examples), adoption and impact will be lower for this solution. It is not possible to set all biomass-dependent solutions to high adoption levels, add up their impacts, and determine an accurate combined emissions impact.

Note that we calculated the current climate impact using a current materials baseline that includes a small fraction of cellulose. This means that the reported current adoption impact is a slight underestimate compared with the impacts for replacing entirely conventional insulation with the current amount of cellulose insulation in use.

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Table 7. Climate impact at different levels of adoption.

Unit: Gt CO₂‑eq/yr, 100-yr basis

Current adoption 0.022
Achievable – high 0.046
Achievable – low 0.12
Achievable ceiling 0.22
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Additional Benefits

Income and Work

Some alternative insulations can be cheaper than conventional materials. Although there is large variation in evaluation methods and reported costs, our analysis found that cellulose and plant fibers are cheaper than conventional insulation materials such as stone wool, glass wool, and EPS (Figure 1). Depending on the applicable climate conditions and insulation form, switching to alternative insulation materials can result in cost savings for consumers, including homeowners and business owners.

Health

Conventional insulation materials may contribute to poor indoor air quality, especially during installation, and contribute to eye, skin, and lung irritation (Naldzhiev et al., 2020; Stamm et al., 2022; Wi et al., 2021). Additionally, off-gassing of flame retardants and other volatile organic compounds and by-products of conventional insulation can occur shortly after installation (Naldzhiev et al., 2020). Using bio-based alternative insulation products can minimize the health risks during and after installation (McGrath et al., 2023).

Water Resources

Although there is not a scientifically consistent approach to compare the environmental impacts of conventional and alternative insulation materials, a review analysis of 47 studies on insulation concluded that bio-based insulation materials generally have lower impacts as measured through acidification, eutrophication, and photochemical ozone creation potentials than do conventional materials (Füchsl et al., 2022). Other alternative materials such as wood fiber and miscanthus also tend to have a lower environmental footprint (Schulte et al., 2021). The water demand for wood and cellulose is significantly lower than that for EPS (about 2.8 and 20.8 l/kg respectively compared with 192.7 l/kg for EPS) (Zabalza Bribián et al., 2011). While the limited evidence suggests that the alternative material tends to be better environmentally, there is an urgent need to conduct life cycle assessments using a consistent approach to estimate the impact of these materials.

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Risks

Cellulose insulation is susceptible to water absorption, which can lead to mold growth in wet or humid environments (Andersen & Rasmussen, 2025; Petcu et al., 2023). Reducing this risk either requires an antifungal treatment for the material or limits adoption to particular climates. The thermal performance of cellulose insulation can decrease over time due to water absorption, settling, or temperature changes, but installing it as dense-packed or damp-spray can alleviate this problem (Wang & Wang, 2023; Wilson, 2021).

Bio-based insulation materials tend to be combustible, meaning they contribute more to the spread of a fire than non-combustible stone or glass insulation. Some bio-based materials are classified as having minimal contribution to a fire, such as some cellulose forms, rice husk, and flax (Kumar et al., 2020). These materials are less likely to contribute to a fire than very combustible plastic insulation such as EPS, XPS, and PUR. Fire codes – as well as other building and energy codes – could limit adoption, risking a lack of solution uptake due to regulatory setbacks (Northeast Bio-Based Materials Collective 2023 Summit Proceedings, 2023). 

Additives such as fire retardants and anti-fungal agents are added to bio-based insulation along with synthetic binders, which can lead to indoor air pollution from organic compounds, although likely in low concentrations (Maskell et al., 2015; Rabbat et al., 2022).

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Interactions with Other Solutions

Reinforcing

Upgrading insulation to lower-cost and lower-emitting alternative materials should increase the adoption of other building envelope solutions as they can be installed simultaneously to optimize cost and performance. 

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Increasing the manufacturing of cellulose insulation, which contains large amounts of recycled paper, could increase the revenues for paper recycling.

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Competing

This solution uses wood as a feedstock (raw material), including wood, and crop residues. Because the total projected demand for woody biomass for climate solutions exceeds the supply, not all of these solutions will be able to achieve their potential adoption. This solution is in competition with the following solutions for raw material:

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Reducing the demand for conventional insulation products and instead making insulation that produces fewer GHGs during manufacturing would slightly reduce the global climate impact of other industrial manufacturing solutions. This is because less energy overall would be used for manufacturing, and therefore other technologies for emissions reductions would be less impactful for insulation production.

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Dashboard

Solution Basics

insulation units of 100 m² and 1 m²·K/W

t CO₂-eq (100-yr)/unit
00.981.59
units/yr
Current 1.4×10⁷ 02.9×10⁷7.3×10⁷
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 0.022 0.0460.12
US$ per t CO₂-eq
-121
Emergency Brake

CO₂, F-gas

Trade-offs

Bio-based insulation materials including cellulose often have lower thermal resistance than some conventional insulation materials. In particular, bio-based materials may require a thicker layer than plastic insulation to reach the same insulating performance (Esau et al., 2021; Rabbat et al., 2022). Usable floor area within a building would need to be sacrificed to accommodate thicker insulation, which would potentially depreciate the structure or impact the aesthetic value (Jelle, 2011). This would be a more significant trade-off for retrofit construction and buildings in densely developed urban areas.

Sourcing bio-based materials has environmental trade-offs that come from cultivating biomass, such as increased land use, fertilizer production, and pesticide application (Schulte et al., 2021). Using waste or recycled materials could minimize these impacts. Binders and flame-retardants may also be required in the final product, leading to more processing and material use (Sustainable Traditional Buildings Alliance, 2024).

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Maps Introduction

The effectiveness of deploying alternative insulation is not inherently dependent on geographic factors since it addresses emissions embodied in the manufacture and deployment of insulation materials. However, due to a lack of related data, we assumed a consistent global breakdown of currently used insulation materials when in reality, the exact mix of insulation currently used in different geographic locations will affect the emissions impact of switching to alternative materials.

Building insulation is used in higher quantities in cold or hot climates, so deploying alternative insulation is more likely to be relevant and adopted in such climates. Other geographic factors also impact adoption: Areas with higher rates of new construction will be better able to design for cellulose or other alternative insulation materials, and drier climates will face a lower risk of mold growth on these materials. Local building codes, including fire codes, can also affect the adoption of alternative materials.

There are no maps for the Deploy Alternative Insulation Materials solution. It is intended to address emissions embodied in the manufacture and deployment of insulation materials and has no intrinsic dependence on geographic factors.

Action Word
Deploy
Solution Title
Alternative Insulation Materials
Classification
Highly Recommended
Lawmakers and Policymakers
  • Enact comprehensive policy plans that utilize all levers, including financial incentives, improved building and fire code regulations, and educational programs to advance the transition to alternative insulation.
  • Create government procurement policies that become stricter over time and mandate the use of alternative insulation or implement GWP limits in government buildings.
  • Update insulation installation regulations to encourage more sustainable practices and materials.
  • Offer financial incentives such as subsidies, tax credits, and grants for manufacturers, start-ups, and alternative insulation installers.
  • Remove financial and regulatory incentives for conventional insulation.
  • Create and enforce embodied carbon disclosure requirements for new commercial construction.
  • Create energy efficiency standards that periodically increase for insulation materials and buildings.
  • Regulate demolition of old buildings to require proper disposal of conventional insulation to ensure emissions are avoided and gases are destroyed.
  • Create reference standards for the performance and properties of alternative insulation materials.
  • Invest in R&D to improve alternative insulation materials’ manufacturing, adoption, supply chain access, and circularity.
  • Create green building certification schemes and/or public-private partnerships that offer information, training, and general support for alternative insulation.
  • Offer educational resources, one-stop shops for retrofitting and weatherization, installation demonstrations, and tours of model builds for commercial and private developers, highlighting the cost savings, environmental benefits, and health benefits of alternative insulation.

Further information:

Practitioners
  • Finance or develop only new construction and retrofits that use alternative insulation and other low-carbon practices.
  • Take advantage of financial incentives such as subsidies, tax credits, and grants for installing alternative insulation.
  • Seek or negotiate preferential loan agreements for developers using alternative insulation and other climate-friendly practices.
  • Whenever possible, install insulation that does not use F-gas blowing agents.
  • During demolition, ensure proper disposal of conventional insulation to avoid emissions and destroy residual F-gases.
  • Integrate alternative insulation materials into construction databases, listing prices, and environmental benefits.
  • Enact company policies that disclose embodied carbon of commercial construction.
  • Create new contractual terms that require embodied emissions data from materials and methods from suppliers.
  • Advocate for financial incentives, improved building and fire codes, and educational programs for alternative insulation.
  • Use educational resources, one-stop shops for retrofitting and weatherization, installation demonstrations, and tours of model builds.
  • Conduct research to improve alternative insulation materials’ manufacturing, adoption, supply chain access, and circularity.
  • Create or join green building certification schemes, green building councils, and/or public-private partnerships that offer information, training, and general support for alternative insulation.

Further information:

Business Leaders
  • Finance only new construction and retrofits that utilize alternative insulation and other low-carbon practices.
  • Expand product lines to include alternative insulation materials.
  • Integrate alternative insulation materials into construction databases, listing prices and environmental benefits.
  • Create new contractual terms that require embodied emissions data from materials and methods.
  • Invest in R&D to improve alternative insulation materials’ manufacturing, adoption, supply chain access, and circularity.
  • Advocate for financial incentives, improved building and fire codes, and educational programs for alternative insulation.
  • Join green building certification schemes and/or public-private partnerships that offer information, training, and general support for alternative insulation.
  • Create long-term purchasing agreements with alternative insulation manufacturers to support stable demand and improve economies of scale.

Further information:

Nonprofit Leaders
  • Advocate for financial incentives, improved building and fire codes, and educational programs for alternative insulation.
  • Conduct research to improve alternative insulation materials’ manufacturing, adoption, supply chain access, and circularity.
  • Offer educational resources, one-stop shops for retrofitting and weatherization, installation demonstrations, and tours of model builds for commercial and private developers, highlighting the cost savings and environmental benefits of alternative insulation.
  • Create, join, or administer green building certification schemes and/or public-private partnerships that offer information, training, and general support for alternative insulation.

Further information:

Investors
  • Finance only new construction and retrofits that utilize alternative insulation and other low-carbon practices.
  • Invest in R&D and start-ups to improve alternative insulation materials’ manufacturing, adoption, supply chain access, and circularity.
  • Issue green bonds to invest in projects that use alternative insulation.
  • Offer preferential loan agreements for developers utilizing alternative insulation and other climate-friendly practices.
  • Create new contractual terms that require embodied emissions data from materials and methods.
  • Join green building certification schemes and/or public-private partnerships that offer information, training, and general support for alternative insulation.

Further information:

Philanthropists and International Aid Agencies
  • Finance only new construction and retrofits that utilize alternative insulation and other low-carbon practices.
  • Offer grants for developers using alternative insulation and other climate-friendly practices.
  • Create financing programs for private construction in low-income or under-resourced communities.
  • Create new contractual terms that require embodied emissions data from materials and methods.
  • Advocate for financial incentives, improved building and fire codes, and educational programs for alternative insulation.
  • Fund research to improve alternative insulation materials’ manufacturing, adoption, supply chain access, and circularity.
  • Offer educational resources, one-stop shops for retrofitting and weatherization, installation demonstrations, and tours of model builds for commercial and private developers, highlighting the cost savings and environmental benefits of alternative insulation.
  • Create or join green building certification schemes and/or public-private partnerships that offer information, training, and general support for alternative insulation.

Further information:

Thought Leaders
  • Advocate for financial incentives, improved building and fire codes, and educational programs for alternative insulation.
  • Conduct research to improve alternative insulation materials’ manufacturing, adoption, supply chain access, and circularity.
  • Offer or amplify educational resources, one-stop shops for retrofitting and weatherization, installation demonstrations, and tours of model builds for commercial and private developers, highlighting the cost savings and environmental benefits of alternative insulation.
  • Create, join, or administer green building certification schemes and/or public-private partnerships that offer information, training, and general support for alternative insulation.

Further information:

Technologists and Researchers
  • Develop and improve existing alternative insulation materials or innovate new materials with enhanced insulation performance.
  • Investigate ways to increase the durability of alternative insulation, such as resistance to moisture, pests, and fire.
  • Find uses for recycled materials in alternative insulation and ways to improve the circular economy.
  • Innovate new manufacturing methods that reduce electricity use and emissions.
  • Design new application systems for alternative insulation that can be done without much additional training or licensing/certification.
  • Create new methods of disposal for conventional insulation during demolitions.
  • Research adoption rates of alternative insulation materials across regions and environments.

Further information:

Communities, Households, and Individuals
  • Finance or develop only new construction and retrofits that utilize alternative insulation and other low-carbon practices.
  • Take advantage of financial incentives such as subsidies, tax credits, and grants for installing alternative insulation.
  • Whenever possible, install insulation that does not use F-gas blowing agents.
  • Advocate for financial incentives, improved building and fire codes, and educational programs for alternative insulation.
  • Conduct local research to improve alternative insulation materials’ manufacturing, adoption, supply chain access, and circularity.
  • Organize local “green home tours” and open houses to showcase climate-friendly builds and foster demand by highlighting cost savings and environmental benefits of alternative insulation.
  • Create or join green building certification schemes, green building councils, and/or public-private partnerships that offer information, training, and general support for alternative insulation.
  • Capture community feedback and share it with local policymakers to address barriers such as permitting logistics or upfront costs, helping to share policies that drive adoption.

Further information:

Sources
Evidence Base

Consensus of effectiveness in reducing building sector emissions: Mixed

There is scientific consensus that using building insulation with lower embodied emissions will reduce GHG emissions, but expert opinions about the magnitude of possible emissions reductions as well as the accuracy of determining these reductions are mixed. 

Biswas et al. (2016) determined that, for insulation, avoided emissions from reduced heating and cooling energy tend to outweigh the embodied emissions. However, others emphasize that as buildings become more energy-efficient, material embodied emissions become a larger factor in their carbon footprint (Cabeza et al., 2021; Grazieschi et al., 2021). Embodied emissions from insulation can be substantial: Esau et al. (2021) analyzed a mixed-use multifamily building and found that selecting low-embodied-carbon insulation could reduce building embodied emissions by 16% at no cost premium.

Multiple studies have found that some sustainable insulation materials have lower manufacturing emissions than traditional insulation materials (Asdrubali et al., 2015; Füchsl et al., 2022; Kumar et al., 2020; Schiavoni et al., 2016). However, researchers have highlighted the difficulty in evaluating environmental performance of different insulation materials (Cabeza et al., 2021; Grazieschi et al., 2021). Gelowitz and McArthur (2017) found that construction product Environmental Product Declarations contain many errors and discrepancies due to self-contradictory or missing data. Füschl et al. (2022) conducted a meta-analysis and cautioned that “it does not appear that a definitive ranking [of insulation materials] can be drawn from the literature.” In our analysis, we attempted to compare climate impact between materials, but we acknowledge that this can come from flawed and inconsistent data.

Despite the difficulties in comparing materials, there is high consensus that cellulose is a strong low-emissions insulation option due to its low embodied carbon, high recycled content, and good thermal insulating performance (Wilson, 2021).

The results presented in this document summarize findings from four reviews and meta-analyses, 14 original studies, three reports, 27 Environmental Product Declarations, and two commercial websites reflecting current evidence from eight countries as well as data representing global, North American, or European insulation materials. We recognize this limited geographic scope creates bias, and hope this work inspires research and data sharing on this topic in underrepresented regions.

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Updated Date

Improve Cement Production

Submitted by Drawdown Admin on
Sector
Industry, Materials & Waste
Mode
Cut Emissions
Cluster
Improve Materials
Image
Cement factory
Coming Soon
Off
Summary

Cement is a key ingredient of concrete, a manufactured material used in massive quantities around the world. Cement production generates high CO₂ emissions from the production of clinker, a binding ingredient. These emissions come from not only the chemical reaction that produces clinker, but also burning fossil fuels to provide heat for this reaction. We define the Improve Cement Production solution as reducing GHG emissions related to cement manufacturing by substituting other materials for clinker, using alternative fuels, and improving process efficiency.

Health
Air quality
Description for Social and Search
Improve Cement Production is a Highly Recommended climate solution. It involves using low GHG-emitting materials & reducing emissions from fossil-fuel burning.
Overview

Concrete production requires the manufacturing of 4 Gt of cement annually (U.S. Geological Survey, 2024). Roughly 85% of cement industry GHG emissions come from the production of a key cement component called clinker. Both the clinker formation chemical reaction and fuel combustion for high-temperature clinker kilns release GHGs (Goldman et al., 2023). Figure 1 illustrates the manufacturing steps responsible for these emissions and highlights how three approaches – clinker substitution, use of alternative fuels, and process efficiency upgrades – could mitigate emissions.

Figure 1. Cement production GHG emissions. Some 85% of GHGs emitted during cement production are released when clinker is produced in high-temperature kilns. The three approaches analyzed in this solution – clinker substitution, alternative fuels, and process efficiency upgrades – aim to mitigate such emissions. Modified from Goldman et al. (2023) via McKinsey.

Diagram of energy used in cement production process

Source: Goldman, S., Majsztrik, P., Sgro Rojas, I., Gavvalapalli, M., Gaikwad, R., Feric, T., Visconti, K., & McMurty, B. (2023). Pathways to commercial liftoff: Low-carbon cement. U.S. Department of Energy.

Clinker substitution replaces a portion of the clinker used in cement with alternative materials, thus reducing the amount of clinker manufactured. This decreases the amount of CO₂ emitted by the chemical reaction and fuel combustion. Clinker is made by heating limestone to convert it to lime. This reaction releases CO₂. Some of the CO₂ production can be eliminated by replacing some of the clinker with substitute materials such as industrial waste products, other cementitious compounds, or available minerals. Clinker substitution also reduces energy demand, lowering emissions from burning fossil fuels. Clinker fraction in cement is often expressed as a clinker-to-cement ratio, which ranges from 0 (no clinker) to 1 (entirely clinker). The most common type of cement, Portland cement, typically has a clinker-to-cement ratio of 0.95, meaning the cement is 95% clinker by mass.

Alternative fuels that can be used to heat cement kilns in place of fossil fuels are typically biomass and waste-based fuels. Cement production uses two kilns, one heated to ~700 °C and the other to ~1,400 °C (U.S. Department of Energy, 2022). The energy needed to provide this heat typically comes from burning fossil fuels such as oil, gas, or coal on-site, which emits CO₂ as well as small amounts of other GHGs, including methane and nitrous oxide, and air pollutants, including nitrogen oxides, sulfur oxides, and particulate matter (Hottle et al., 2022; Miller & Moore, 2020). Switching to alternative fuels decreases emissions by reducing the mining and combustion of fossil fuels and recovering energy from waste streams that would have otherwise released GHG during decomposition or incineration (Georgiopoulou & Lyberatos, 2018).

Efficiency upgrades include a broad suite of technologies such as improved controls, electrically efficient equipment (e.g., mills, fans, and motors), thermally efficient and multistage kilns, and waste heat recovery. These improvements lead to less wasted heat and input energy, and therefore require less fossil fuel burning during manufacturing. In particular, upgrading kilns has the potential for high emissions mitigation (Mokhtar & Nasooti, 2020; Morrow III et al., 2014). Kiln upgrades can include processing dry raw material (which is more efficient than expending energy to remove moisture from wet feedstock), adding a preheater that uses kiln exhaust gas to dry and preheat raw material, and adding a precalciner kiln that uses some of the fuel to partially calcine raw material at a lower temperature (European Cement Research Academy, 2022; Schorcht et al., 2013). Each study included in our analysis for effectiveness and cost included a set group of technologies that were considered to be process efficiency upgrades.

The cost and avoided emissions from each approach vary depending on the other technologies in use at a particular cement plant (Glenk et al., 2023). While coupling the impacts of the approaches would provide the most accurate representation of this solution, that analysis is complex and outside the scope of this assessment. Therefore, we will consider the three approaches separately. 

5.32%
of total global emissions
4.1 Billion

Worldwide, we make 4.1 billion metric tons of cement every year.

3.2 Gt

In the process, we produce more than 3 Gt CO₂‑eq of greenhouse gases – 5.32% of global annual emissions

Take Action Intro

Would you like to help reduce the climate impacts of cement production? Below are some ways you make a difference, depending on the roles you play in your professional or personal life.

These actions are meant to be starting points for involvement and may or may not be the most important, impactful, or doable actions you can take. We encourage you to explore, get creative, and take a step that is right for you!

Afsah, S. (2004). CDM potential in the cement sector: The challenge of demonstrating additionality. Performeks LLC. Link to source: https://www.performeks.com/media/downloads/CDM-Cement%20Sector_May%202004.pdf 

Cannon, C., Guido, V., & Wright, L. (2021). Concrete solutions guide: Mix it up: Supplementary cementitious materials (SCMs). RMI. Link to source: https://rmi.org/wp-content/uploads/2021/08/ConcreteGuide2.pdf 

Cao, Z., Masanet, E., Tiwari, A., and Akolawala, S. (2021). Decarbonizing concrete: Deep decarbonization pathways for the cement and concrete cycle in the United States, India, and China. Industrial Sustainability Analysis Laboratory. 

Cavalett, O., Watanabe, M. D. B., Voldsund, M., Roussanaly, S., & Cherubini, F. (2024). Paving the way for sustainable decarbonization of the European cement industry. Nature Sustainability, 7, 568–580. Link to source: https://doi.org/10.1038/s41893-024-01320-y 

CEMBUREAU. (n.d.) Clinker substitution. Retrieved August 7, 2024, from Link to source: https://lowcarboneconomy.cembureau.eu/5-parallel-routes/resource-efficiency/clinker-substitution/ 

Clark, G., Davis, M., Shibani, & Kumar, A. (2024). Assessment of fuel switching as a decarbonization strategy in the cement sector. Energy Conversion and Management, 312, 118585. Link to source: https://doi.org/10.1016/j.enconman.2024.118585 

ClimeCo. (2022). Low carbon cement production. Link to source: https://www.climateactionreserve.org/wp-content/uploads/2022/10/Low-Carbon-Cement-Issue-Paper-05-20-2022_final.pdf 

Daehn, K., Basuhi, R., Gregory, J., Berlinger, M., Somjit, V., & Olivetti, E. A. (2022). Innovations to decarbonize materials industries. Nature Reviews Materials, 7, 275–294. Link to source: https://doi.org/10.1038/s41578-021-00376-y 

de Puy Kamp, M. (2021, July 9). How marginalized communities in the South are paying the price for ‘green energy’ in Europe. CNN. Link to source: https://edition.cnn.com/interactive/2021/07/us/american-south-biomass-energy-invs/ 

European Cement Research Academy. (2022). The ECRA technology papers 2022: State of the art cement manufacturing, current technologies and their future development. Link to source: https://api.ecra-online.org/fileadmin/files/tp/ECRA_Technology_Papers_2022.pdf 

Georgiopoulou, M., & Lyberatos, G. (2018). Life cycle assessment of the use of alternative fuels in cement kilns: A case study. Journal of Environmental Management, 216, 224–234. Link to source: https://doi.org/10.1016/j.jenvman.2017.07.017 

Glenk, G., Kelnhofer, A., Meier, R., & Reichelstein, S. (2023). Cost-efficient pathways to decarbonizing Portland cement production. ZEW - Centre for European Economic Research Discussion Paper No. 23-023. Link to source: https://doi.org/10.2139/ssrn.4434830 

Global Cement and Concrete Association. (2021). Concrete future: The GCCA 2050 cement and concrete industry roadmap for net zero concrete. Link to source: https://gccassociation.org/concretefuture/wp-content/uploads/2021/10/GCCA-Concrete-Future-Roadmap-Document-AW.pdf 

Goldman, S., Majsztrik, P., Sgro Rojas, I., Gavvalapalli, M., Gaikwad, R., Feric, T., Visconti, K., & McMurty, B. (2023). Pathways to commercial liftoff: Low-carbon cement. U.S. Department of Energy. 

Gómez, D. R., & Watterson, J. D., et al. (2006). Stationary combustion. In S. Eggelston, L. Buendia, K. Miwa, T. Ngara, & K. Tanabe (Eds.), 2006 IPCC guidelines for national greenhouse gas inventories (Vol. 2). Institute for Global Environmental Strategies (IGES) for the IPCC. Link to source: https://www.ipcc-nggip.iges.or.jp/public/2006gl/pdf/2_Volume2/V2_2_Ch2_Stationary_Combustion.pdf 

Griffiths, S., Sovacool, B. K., Furszyfer Del Rio, D. D., Foley, A. M., Bazilian, M. D., Kim, J., & Uratani, J. M. (2023). Decarbonizing the cement and concrete industry: A systematic review of socio-technical systems, technological innovations, and policy options. Renewable and Sustainable Energy Reviews, 180, 113291. Link to source: https://doi.org/10.1016/j.rser.2023.113291 

Habert, G., Miller, S. A., John, V. M., Provis, J. L., Favier, A., Horvath, A., & Scrivener, K. L. (2020). Environmental impacts and decarbonization strategies in the cement and concrete industries. Nature Reviews Earth & Environment, 1, 559–573. Link to source: https://doi.org/10.1038/s43017-020-0093-3 

Hottle, T., Hawkins, T. R., Chiquelin, C., Lange, B., Young, B., Sun, P., Elgowainy, A., & Wang, M. (2022). Environmental life-cycle assessment of concrete produced in the United States. Journal of Cleaner Production, 363, 131834. Link to source: https://doi.org/10.1016/j.jclepro.2022.131834 

International Energy Agency. (2018). Technology roadmap: Low-carbon transition in the cement industry. Link to source: https://www.iea.org/reports/technology-roadmap-low-carbon-transition-in-the-cement-industry 

International Energy Agency. (2023a). CO2 emitted and captured in the cement sector and clinker-to-cement ratio in the Net Zero Scenario, 2015–2030. Link to source: https://www.iea.org/data-and-statistics/charts/co2-emitted-and-captured-in-the-cement-sector-and-clinker-to-cement-ratio-in-the-net-zero-scenario-2015-2030 

International Energy Agency. (2023b). Global cement production in the Net Zero Scenario, 2010–2030. Link to source: https://www.iea.org/data-and-statistics/charts/global-cement-production-in-the-net-zero-scenario-2010-2030-5260 

International Energy Agency. (2023c). Global thermal energy intensity of clinker production by fuel in the Net Zero Scenario, 2010–2030. Link to source: https://www.iea.org/data-and-statistics/charts/global-thermal-energy-intensity-of-clinker-production-by-fuel-in-the-net-zero-scenario-2010-2030 

Isabirye, A., & Sinha, A. (2023). Manufacturing sector: Cement manufacturing emissions. ClimateTRACE. Link to source: https://github.com/climatetracecoalition/methodology-documents/blob/main/2023/Manufacturing/Manufacturing%20and%20Industrial%20Processes%20sector-%20Cement%20Manufacturing%20Emissions%20methodology.docx.pdf 

Juenger, M. C. G., Snellings, R., & Bernal, S. A. (2019). Supplementary cementitious materials: New sources, characterization, and performance insights. Cement and Concrete Research, 122, 257–273. Link to source: https://doi.org/10.1016/j.cemconres.2019.05.008 

Miller, S. A., & Moore, F. C. (2020). Climate and health damages from global concrete production. Nature Climate Change, 10(5), 439–443. Link to source: https://doi.org/10.1038/s41558-020-0733-0

Mokhtar, A., & Nasooti, M. (2020). A decision support tool for cement industry to select energy efficiency measures. Energy Strategy Reviews, 28, 100458. Link to source: https://doi.org/10.1016/j.esr.2020.100458 

Morrow III, W. R., Hasanbeigi, A., Sathaye, J., & Xu, T. (2014). Assessment of energy efficiency improvement and CO2 emission reduction potentials in India's cement and iron & steel industries. Journal of Cleaner Production, 65, 131–141. Link to source: https://doi.org/10.1016/j.jclepro.2013.07.022 

Rissman, J., Bataille, C., Masanet, E., Aden, N., Morrow III, W. R., Zhou, N., Elliott, N., Dell, R., Heeren, N., Huckestein, B., Cresko, J., Miller, S. A., Roy, J., Fennell, P., Cremmins, B., Blank, T. K., Hone, D., Williams, E. D., de la Rue du Can, S., …Helseth, J. (2020). Technologies and policies to decarbonize global industry: Review and assessment of mitigation drivers through 2070. Applied Energy, 266, 114848. Link to source: https://doi.org/10.1016/j.apenergy.2020.114848 

Schorcht, F., Kourti, I., Scalet, B. M., Roudier, S., & Delgado Sancho L. (2013). Best available techniques (BAT) reference document for the production of cement, lime and magnesium oxide – Industrial Emissions Directive 2010/75/EU (integrated pollution prevention and control) (Joint Research Center publication JRC 83006). European Commission, Joint Research Centre, Institute for Prospective Technological Studies. Link to source: https://doi.org/10.2788/12850 

Searchinger, T., Peng, L., Zionts, J., & Waite, R. (2024). The global land squeeze: Managing the growing competition for land. World Resources Institute. Link to source: https://www.wri.org/research/global-land-squeeze-managing-growing-competition-land

Shah, I. H., Miller, S. A., Jiang, D., & Myers, R. J. (2022). Cement substitution with secondary materials can reduce annual global CO2 emissions by up to 1.3 gigatons. Nature Communications, 13, 5758. Link to source: https://doi.org/10.1038/s41467-022-33289-7 

Sinha, A., and Crane, V. (2024). Manufacturing and industrial processes sector: Cement manufacturing emissions. TransitionZero, UK, Climate TRACE Emissions Inventory. Link to source: https://climatetrace.org

Snellings, R. (2016). Assessing, understanding and unlocking supplementary cementitious materials. RILEM Technical Letters, 1, 50–55. Link to source: https://doi.org/10.21809/rilemtechlett.2016.12 

Snellings, R., Suraneni, P., & Skibsted, J. (2023). Future and emerging supplementary cementitious materials. Cement and Concrete Research, 171, 107199. Link to source: https://doi.org/10.1016/j.cemconres.2023.107199

U.S. Department of Energy. (2022). Industrial decarbonization roadmap. Link to source: https://www.energy.gov/sites/default/files/2022-09/Industrial%20Decarbonization%20Roadmap.pdf 

U.S. Environmental Protection Agency. (2016). Greenhouse gas inventory guidance: Direct emissions from stationary combustion sources. Link to source: https://www.epa.gov/sites/default/files/2016-03/documents/stationaryemissions_3_2016.pdf 

U.S. Federal Highway Administration. (n.d.). Use of supplementary cementitious materials (SCMs) in concrete mixtures (FHWA-HIF-19-054). U.S. Department of Transportation. Link to source: https://www.fhwa.dot.gov/pavement/concrete/trailer/resources/hif19054.pdf 

U.S. Geological Survey. (2024). Mineral commodity summaries 2024. https://doi.org/10.3133/mcs2024 

Yang, X., Teng, F., & Wang, G. (2013). Incorporating environmental co-benefits into climate policies: A regional study of the cement industry in China. Applied Energy, 112, 1446–1453. Link to source: https://doi.org/10.1016/j.apenergy.2013.03.040

Zhang, S., Ren, H., Zhou, W., Yu, Y., & Chen, C. (2018). Assessing air pollution abatement co-benefits of energy efficiency improvement in cement industry: A city level analysis. Journal of Cleaner Production, 185, 761–771. Link to source: https://doi.org/10.1016/j.jclepro.2018.02.293

Zhang, S., Worrell, E., & Crijns-Graus, W. (2015). Evaluating co-benefits of energy efficiency and air pollution abatement in China’s cement industry. Applied Energy, 147, 192–213. Link to source: https://doi.org/10.1016/j.apenergy.2015.02.081

Zhang, S., Xie, Y., Sander, R., Yue, H., & Shu, Y. (2021). Potentials of energy efficiency improvement and energy–emission–health nexus in Jing-Jin-Ji’s cement industry. Journal of Cleaner Production, 278, 123335. Link to source: https://doi.org/10.1016/j.jclepro.2020.123335

Credits

Lead Fellow

  • Sarah Gleeson, Ph.D.

Contributors

  • James Gerber, Ph.D.

  • Yusuf Jameel, Ph.D.

  • Daniel Jasper

  • Alex Sweeney

Internal Reviewers

  • Aiyana Bodi

  • Hannah Henkin

  • Ted Otte

  • Amanda D. Smith, Ph.D.

  • Christina Swanson, Ph.D.

Effectiveness

Cement production currently emits 760,000 t CO₂‑eq /Mt cement produced, based on our analysis. With global cement production exceeding 4 Gt/yr (U.S. Geological Survey, 2024), the scale of emissions to be mitigated is large.

Clinker substitution is the most effective of the three approaches at reducing emissions, eliminating approximately 240,000 t CO₂‑eq /Mt cement produced. This is equivalent to 690,000 t CO₂‑eq /Mt clinker avoided (Table 1a). This estimate is based on expert predictions of GHG savings for realistic target levels of clinker replacement with material substitutes.

Alternative fuels and efficiency upgrades have carbon abatement potentials of 96,000 and 90,000 t CO₂‑eq /Mt cement produced, respectively, when calculated based on production levels (Table 1b). Since the units of adoption for process efficiency upgrades are GJ thermal energy input, when calculating climate impact we used an effectiveness per GJ of thermal energy, calculated using an emission factor for fuel combustion. This effectiveness is 0.0847 t CO₂ /GJ thermal energy input (Table 1c; Gómez & Watterson et al., 2006; International Energy Agency [IEA], 2023c). 

We calculated the effectiveness of these three approaches separately. Because the implementation of each affects the effectiveness potential of the others (Glenk et al., 2023), the actual effectiveness will be lower when the approaches are implemented together.

Emissions reductions from these approaches can be directly related to how the approach impacts GHG emissions from clinker production and fossil fuel burning. However, sourcing, processing, and transporting clinker substitutes and alternative fuels also produces GHGs. Our data sources did not always report whether such indirect emissions were accounted for, so our analysis primarily focuses on direct emissions. Further analysis of other life-cycle emissions considerations would be valuable in future research; however, indirect emission levels for both clinker substitutes and alternative fuels are reportedly small compared to direct emissions (European Cement Research Academy, 2022; Shah et al., 2022).

Additionally, cement industry members sometimes assume that there are no direct emissions from burning biomass fuels (Goldman et al., 2023). As a result, we assume that direct emissions from biomass are not fully accounted for in the data and therefore that the climate benefit of using alternative fuels may be exaggerated.

While other GHGs, including methane and nitrous oxide, are also released during cement manufacturing, these gases represent a small fraction (<3% combined) of overall CO₂‑eq emissions so we considered them negligible in our calculations (U.S. Environmental Protection Agency, 2016; Hottle et al., 2022). 

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Table 1. Effectiveness at reducing emissions.

Unit: t CO₂‑eq /Mt clinker avoided, 100-year basis

25th percentile 540,000
Mean 710,000
Median (50th percentile) 690,000
75th percentile 860,000

Unit: t CO₂‑eq /Mt cement produced (100-year basis)

25th percentile 77,000
Mean 94,000
Median (50th percentile) 96,000
75th percentile 99,000

Unit: t CO₂‑eq /GJ thermal energy input (100-year basis)

Calculated value 0.0847
Cost

All three approaches to mitigating cement emissions result in cost savings by our analysis. Despite high initial costs, when considering the long technology lifetime and annual operational savings, the net lifetime and annualized costs are lower than conventional cement production.

Clinker substitution has the highest net savings of the three approaches, with US$7 million/Mt cement produced generating savings of US$30/t CO₂‑eq (Table 2a). While initial and operating costs may vary between different substitute materials, we averaged all material types for each cost estimate. Goldman et al. (2023) and the European Cement Research Academy (2022) offer breakdowns of cost by material type.

Alternative fuels generate savings of US$5 million/Mt cement, or US$50/t CO₂‑eq mitigated (Table 2b). For both clinker substitution and alternative fuels, cost and emissions will vary based on local material availability (Cannon et al., 2021). We assumed equivalent costs for all alternative fuel types.

Efficiency upgrades save US$6 million/Mt cement and have the highest cost savings per unit climate impact (US$60/t CO₂‑eq ). While process efficiency upgrades encompass many different technologies, this cost estimate incorporates the costs of two of the technologies yielding high avoided emissions – replacing long kilns with preheater/precalciner kilns and implementing efficient clinker cooler technology. Between these technologies, upgrading to preheater/precalciner kilns represents most of the initial cost increase and the operational cost savings (European Cement Research Academy, 2022).

The costs of each approach (Table 2) were calculated as amortized initial costs of upgrading plants, added to the expected changes in annual operational costs. Only very limited data are available for price premiums on low-carbon cement. Therefore, we did not include any revenues for low-carbon cement. 

While we calculated these costs separately, in reality the cost for implementing multiple approaches will be different due to interactions between technologies (Glenk et al., 2023). For example, material processing equipment could change based on the type of clinker substitute materials. We do not expect the costs to be additive as we assumed in our analysis, and limited cost data means that this estimate is based on limited sources.

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Table 2: Cost per unit climate impact.

Unit: 2023 US$/t CO₂‑eq , 100-yr basis

Clinker substitution –30

Negative values reflect cost savings.

Unit: 2023 US$/t CO₂‑eq , 100-yr basis

Alternative fuels –50

Negative values reflect cost savings.

Unit: 2023 US$/t CO₂‑eq , 100-yr basis

Process efficiency upgrades –60

Negative values reflect cost savings.

Learning Curve

The technologies needed for all approaches in this solution are well developed and ready to deploy at scale, so we did not consider learning curves. 

We did not find any global data on cost changes related to adoption levels for equipment, including energy-efficient processing technologies, dry-process kilns, or material storage. A portion of the solution’s initial costs come from plant downtimes, which would not be impacted by the technology learning curve. For feedstock components of the solution, including alternative fuels and clinker material substitutes, the costs will be subject to material availability, market prices, and transportation, and therefore will not necessarily decrease with adoption.

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Speed of Action

Speed of action refers to how quickly a climate solution physically affects the atmosphere after it is deployed. This is different from speed of deployment, which is the pace at which solutions are adopted.

At Project Drawdown, we define the speed of action for each climate solution as emergency brake, gradual, or delayed.

Improve Cement Production is a GRADUAL climate solution. It has a steady, linear impact on the atmosphere. The cumulative effect over time builds as a straight line.

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Caveats

Manufacturing emissions reductions due to clinker substitution, alternative fuels, and process efficiency upgrades are both permanent and additional. 

Permanence 

There is a low risk that the emission reductions this solution generates will be reversed in the next 100 years. This approach calls for reduced burning of fossil fuels and less calcination of limestone into clinker, thereby avoiding emissions from these activities. Meanwhile, carbon that is not released as CO₂ due to these technologies will remain stable in limestone or fossil fuel reserves indefinitely, making the emissions mitigation permanent.

Additionality 

These cement emissions reductions are additional if they are adopted in amounts higher than what is currently required and used in local or regional cement manufacturing. Afsah (2004) assessed additionality based on whether it represents “not common practice” from a national standpoint of market share or adoption. ClimeCo (2022) suggested that for clinker material substitutes to be considered additional, the substitute needs to meet two criteria: The replacement is not mandated by law, and new or emerging materials are used.

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Current Adoption

Few global data are available for current adoption. Most data are from regional sources, typically the United States or Europe. As a result, we do not expect these data to be representative at the global level – China and India alone produce more than 60% of the world’s cement (U.S. Geological Survey, 2024). Therefore, we quantified adoption only from a limited number of worldwide sources, using the adoption units listed in Figure 2.

Clinker substitution is challenging to assess for adoption, since it is implemented with a broad range of materials and replacement fractions. We therefore simplified adoption in this analysis by quantifying it as the amount of global cement material that is not clinker. The adoption tonnage (Table 3a) represents Mt of clinker production avoided, using conventional Portland cement (5% non-clinker) as a baseline (CEMBUREAU, n.d.). Note that this is different from the way we considered cement tonnage for effectiveness and cost. There, we calculated emissions reductions for a Mt of cement produced including substituted material. For adoption, however, we considered tonnage to be clinker avoided (based on amount replaced with other materials).

The IEA (2023a) and the European Cement Research Academy (2022) estimated the global clinker-to-cement ratio to be approximately 0.72, meaning that 28% of cement composition is material other than clinker. This correlates to 980 Mt clinker avoided/yr used over the Portland cement baseline.

Alternative fuels are currently used to replace approximately 7% of fossil fuels in global cement production (Global Cement and Concrete Association, 2021; IEA, 2023c). We assumed this means approximately 300 Mt cement/yr are currently produced with biomass and waste fuels (Table 3b).

Efficiency upgrades encompass dozens of technological improvements, which – along with a paucity of available data – make adoption levels challenging to assess. To estimate the current state of energy usage in the cement industry, we used the IEA (2023c) estimate of 3,550,000 GJ/Mt clinker as the 2022 benchmark thermal energy input for clinker production. This value does not include electrical efficiency and can vary based on fuel mix, but approximates the current state of energy use. We converted it to GJ/yr using amounts of annual clinker production, yielding 10.5 billion GJ thermal energy consumed each year for clinker production. Since there is no baseline for efficiency, we consider this value to be the zero adoption scenario and the current adoption to be not determined (Table 3c).

For the other approaches, there is a clear baseline case of “zero adoption” where no substitutes or alternative fuels are in use. However, thermal energy input is an energy use indicator that represents a continuum with no clear baseline. We therefore had to benchmark future energy savings against an initial value, which we chose as 2022 since it provided the most recent available data. All future estimates represent annual GHG savings relative to global cement production’s 2022 GHG emissions levels.

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Table 3. Current adoption level (2022).

Unit: Mt clinker avoided/yr

Median (50th percentile) 980

Unit: Mt cement produced using alternative fuels/yr

Median (50th percentile) 300

Unit: GJ thermal energy input/yr saved

Median (50th percentile) not determined
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Adoption Trend

Clinker substitution has experienced relatively unchanged adoption worldwide in recent years (Table 4a). Since 2016, there has been a small increase in clinker-to-cement ratio, indicating a slight decrease in adoption of this approach (IEA, 2023a). This corresponds to 40 Mt fewer clinker material substitutes being used each year, on average. 

Alternative fuels adoption is slowly on the rise as percent of fuel mix (Table 4b). According to the IEA (2023c), the percentage of global clinker produced by bioenergy and waste fuels increased from 6.5% in 2015 to 8.5% in 2022. This corresponds to a median annual increase of 12 Mt cement/yr produced by alternative fuels. 

The IEA (2023c) reported efficiency upgrades to have led to a median annual decrease of 5,000 GJ/Mt clinker from 2011 to 2022, representing a –0.14% annual change in energy input. This indicates that processes consuming thermal energy have become slightly more efficient in recent years. When converted to GJ/yr, this is 15 million fewer GJ thermal energy consumed each year (Table 4c).

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Table 4. Adoption trend.

Unit: annual change in Mt clinker avoided/yr

Median (50th percentile) –40

2016–2022 adoption trend

Unit: annual change in Mt cement produced using alternative fuels/yr

Median (50th percentile) 12

2015–2022 adoption trend

Unit: annual change in GJ thermal energy input/yr

Median (50th percentile) –15,000,000

2011–2022 adoption trend

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Adoption Ceiling

The adoption ceiling (Table 5) is high for all approaches within this solution.

Clinker substitution adoption is likely to be limited primarily by material standards and availability. Across literature, the median adoption ceiling is considered to be 3,000 Mt clinker avoided/yr beyond the Portland cement baseline, yielding a clinker-to-cement ratio of 0.2. Snellings (2016) calculated the worldwide amount of clinker materials substitutes and found that a maximum of ~2,000 Mt/yr would be available, which would result in a clinker-to-cement ratio of approximately 0.5. In the future, some waste materials – like fly ash and ground granulated blast furnace slag – are likely to be less available so increasing the possible substitute amounts would require research on new materials or cement properties.

Alternative fuels are typically assumed to be applicable to roughly 90% of cement production globally, or approximately 4,000 Mt cement/yr at 2022 global production levels (Daehn et al., 2022). In theory, kilns can use 100% alternative fuels, although composition of the fuel can influence the trace elements or calorific value (European Cement Research Academy, 2022). In particular, several analyses point to the lower calorific value of alternative fuels as an adoption-limiting factor. Cavalett et al. (2024) considered 90% to be the maximum. A separate analysis of Canadian cement production determined that 65% is the threshold due to lower-calorie fuels only being applicable in a precalciner kiln – the equipment where fuel is used to begin decomposing limestone through the calcination process (Clark et al., 2024).

Efficiency upgrades have their adoption ceiling limited by the minimum thermal energy demand needed to run cement kilns. The European Cement Research Academy estimates this lower threshold of energy input to be approximately 2,300,000 GJ/Mt clinker, considering chemical reaction and evaporation energy needs (European Cement Research Academy, 2022). This converts to 6.9 billion GJ thermal energy used each year, or 3.6 billion GJ/yr saved over current thermal energy efficiency levels (Table 5c).

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Table 5. Adoption ceiling.

Unit: Mt clinker avoided/yr

Median (50th percentile) 3,000

Unit: Mt cement produced using alternative fuels/yr

Median (50th percentile) 4,000

Unit: GJ thermal energy input/yr saved over current levels

Median (50th percentile) 3,600,000,000
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Achievable Adoption

Clinker substitution achievable adoption (Table 6a) is primarily limited by material availability and initial costs. Global estimates generally expect 30–50% of total substituted material to be reasonable, which correlates to a clinker-to-cement ratio of 0.4–0.6 and 1,000–2,000 Mt clinker avoided/yr (Habert et al., 2020; European Cement Research Academy, 2022). In a separate U.S.-specific analysis, the substitute amount was projected to vary from 5% to 45% depending on the availability and performance of the material substitute (Goldman et al., 2023).

Alternative fuels are projected to account for roughly 40% of the cement fuel mix in 2050 for both global and North American estimates. Taking the median of the global achievable adoption estimates, this correlates to 2,000 Mt cement/yr that would be produced using alternative kiln fuels. As a low estimate, if the current adoption trend holds, approximately 16% of global cement fuel (producing 610 Mt cement/yr) will come from biomass and waste (IEA, 2023c). A reasonable adoption range is 610–2,000 Mt cement/yr (Table 6b), although some European countries currently have ~80% adoption of alternative fuels, meaning that >40% adoption in an aggressive 2050 scenario may be feasible (Cavalett et al., 2024).

Little information exists on projected global adoption of efficiency upgrades between now and 2050. In an analysis of a fraction of cement plants in China, India, and the U.S., it was estimated that these three countries – which represent more than 70% of current cement production worldwide – could reach a thermal energy input of 3.15–3.25 million GJ/Mt clinker by 2060, or 9.30–9.59 billion GJ/yr, which is 0.886–1.18 billion GJ/yr saved over current adoption levels (Table 6c; Cao et al., 2021). Meanwhile, in a European analysis, the European Cement Research Academy (2022) found the same range to be possible by 2050. This is not significantly lower than the current state due to the fact that the highest-producing countries – China and India – have newer manufacturing facilities with more efficient equipment today. Countries with more room to improve in thermal energy efficiency – such as the U.S. – produce only a small fraction of the world’s cement. Approximately 92% of global plants are estimated to use more efficient dry kiln technology, indicating that some of the more energy-saving equipment upgrades are already highly adopted (Isabirye & Sinha, 2023). Therefore, there is less room for increased adoption in kiln technologies worldwide, although electrical efficiency measures could further improve these values.

 While the estimates for tonnage of cement impacted by these approaches are based on 2022 global production numbers, cement production will change through 2050, meaning the impacted mass of cement will also change as these emissions-reducing measures are adopted (IEA, 2023b).

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Table 6. Range of achievable adoption levels.

Unit: Mt clinker avoided/yr

Current adoption 980
Achievable – low 1,000
Achievable – high 2000
Adoption ceiling 3000

Unit: Mt cement produced using alternative fuels/yr

Current adoption 300
Achievable – low 610
Achievable – high 2,000
Adoption ceiling 4,000

Unit: GJ thermal energy input/yr saved over current adoption levels

Current adoption not determined
Achievable – low 886,000,000
Achievable – high 1,180,000,000
Adoption ceiling 3,600,000,000

Note: High adoption in this case results in lower energy use for each unit of cement produced, and thus better efficiency. 

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Improved cement production has high potential for climate impact. By our estimate, cement production is responsible for >5% of global GHG emissions, so mitigating even a portion of these emissions will meaningfully reduce the world’s carbon output.

Clinker substitution has the highest current and potential GHG emissions savings of the three approaches (Table 7a). To calculate the climate impact, we used effectiveness and adoption on the basis of Mt clinker avoided. Climate impact was calculated as:

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$$\frac{\textit{CO₂ abated}}{\textit{yr}} = \frac{\textit{CO₂ abated}}{\textit{clinker avoided}} \times \frac{\textit{clinker avoided}}{\textit{Year}}$$
  • Current GHG savings: 0.67 Gt CO₂‑eq/yr
  • GHG savings ceiling: 2 Gt CO₂‑eq/yr
  • Achievable GHG savings range: 0.7–1 Gt CO₂‑eq/yr

Alternative fuels have a low current climate impact but possess the potential to be adopted for a much greater fraction of the global kiln fuel mix (Table 7b). However, alternative fuels’ potential GHG emissions savings are lower than those for clinker substitutes because alternative fuels have a lower CO₂ mitigation effectiveness. Climate impact is calculated as:

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$$\frac{\textit{CO₂ abated}}{\textit{yr}} = \frac{\textit{CO₂ abated}}{\textit{cement produced}} \times \frac{\textit{cement produced}}{\textit{Year}}$$
  • Current GHG savings: 0.03 Gt CO₂‑eq/yr
  • GHG savings ceiling: 0.4 Gt CO₂‑eq/yr
  • Achievable GHG savings range: 0.06–0.2 Gt CO₂‑eq/yr

Switching to alternative fuels requires the use of biomass as a feedstock. Multiple climate solutions, in addition to improving cement production, require biomass, and projected demand across solutions greatly exceeds supply. The deforestation that would be required to meet demand would produce emissions far greater than any mitigation gains from full deployment of these solutions (Searchinger, 2024). In addition to deforestation, there would also be costs and emissions incurred to transport biomass from where it is produced to where it can be processed and used. Thus, the achievable GHG savings range presented here is only possible if feedstocks are prioritized for this solution. If feedstocks are instead prioritized for other climate solutions (see Interactions for examples), adoption and impact will be lower for this solution. It is not possible to set all biomass-dependent solutions to high adoption levels, add up their impacts, and determine an accurate combined emissions impact.

Efficiency upgrades are the most challenging to assess for climate impact because they represent a broad range of equipment upgrades with no clear baseline efficiency. We considered adoption to be energy savings from the current (2022) baseline in GJ thermal energy input/yr. We converted adoption to climate impact using the emission factor of 0.0847 t CO₂‑eq /GJ thermal energy input (calculated using data from Gómez & Watterson et al., 2006 and IEA, 2023c). The resulting calculation is as follows:

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$$\frac{\textit{CO₂ abated}}{\textit{yr}} = \frac{\textit{CO₂ emissions}}{\textit{thermal energy}} \times \frac{\textit{thermal energy savings from 2022 baseline}}{\textit{yr }}$$
  • Current GHG savings: N/A (we consider the current adoption to be the baseline)
  • GHG savings ceiling: 0.31 Gt CO₂‑eq/yr less than 2022
  • Achievable GHG savings range: 0.0760–0.101 Gt CO₂‑eq/yr less than 2022

While clinker substitution, alternative fuels, and efficiency upgrades are quantified separately here, the adoption of any of these approaches will reduce the climate impact of the others. In particular, the climate impacts for technologies that reduce emissions per Mt of clinker (such as alternative fuels and process efficiency upgrades) will be lower when implemented along with technologies that reduce the amount of clinker used (such as clinker substitution), and vice versa (Glenk et al., 2023). Therefore, these impacts will not be additive, although they will contribute to reduced emissions when implemented together.

While our analysis found clinker substitution to have the highest climate impact, cement manufacturers will have to prioritize these technologies depending on their plant’s existing equipment, local availability of materials, and regional cement standards.

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Table 7. Climate impact at different levels of adoption.

Unit: Gt CO₂‑eq/yr, 100-yr basis

Current adoption 0.67
Achievable – low 0.7
Achievable – high 1
Adoption ceiling 2

Unit: Gt CO₂‑eq/yr, 100-yr basis

Current adoption 0.03
Achievable – low 0.06
Achievable – high 0.2
Adoption ceiling 0.4

Unit: Gt CO₂‑eq/yr, 100-yr basis

Current adoption not determined
Achievable – low 0.075
Achievable – high 0.100
Adoption ceiling 0.31
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Additional Benefits

Health 

Miller & Moore (2020) estimated that the health damages associated with cement production amounted to approximately US$60 billion globally in 2015. These health damages are due to air pollutants produced during cement manufacturing, which would be reduced by this solution as described above. In China, one study estimated that improving energy efficiency in the Jing Jin Ji region’s cement industry could prevent morbidity in 17,000 individuals (Zhang et al., 2021). 

Air Quality 

Cement production is a major contributor to air pollution. Globally, concrete production accounts for approximately 8% of nitrogen oxide emissions, 5% of sulfur oxide emissions, and 5% of particulate matter emissions, with a significant portion of all these emissions stemming exclusively from cement production (Miller & Moore, 2020). Cement-related air pollution is especially acute in China, which produces over 50% of the world’s cement (U.S. Geological Survey, 2024). In 2009, China's cement industry emitted 3.59 Mt of particulate matter, making the industry the leading source of particulate matter emissions in the country (Yang et al., 2013). China also released 0.88 Mt of sulfur dioxide, accounting for about 4% of the national total, and emitted 1.7 Mt of nitrogen oxides (Yang et al., 2013). Process efficiency upgrades in cement manufacturing can reduce these harmful emissions. For example, implementing energy efficiency measures in China’s cement industry could reduce particulate matter by more than 3%, lower sulfur dioxide emissions by more than 15%, and decrease nitrogen oxide emissions by more than 12% by 2030 (Zhang et al., 2015). In Jiangsu province, which is the largest cement producer in China, energy and CO₂ reduction techniques could cut particulate matter and nitrogen oxide emissions by 30% and 56%, respectively, by 2030 (Zhang et al., 2018).

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Risks

According to the U.S. Federal Highway Administration (n.d.), the use of clinker material substitutes in cement slows concrete curing times. Additionally, some clinker material substitutes, such as fly ash, raise ecotoxicity concerns and require safe handling (U.S. Department of Energy, 2022). Robust research and development is needed for new compositions of cement to accelerate testing, standardization, and adoption (Griffiths et al., 2023). Since regional standards vary for cement and concrete, policy and regulatory support designed for specific locations will be necessary to influence adoption levels and rates.

Most clinker material substitutes have limited or regional availability, leading to shortages, high costs, and transportation emissions (Habert et al., 2020). Because some substitute materials are sourced from the waste streams of other industries, such as the coal and steel industries, the long-term feasibility of sourcing these materials is uncertain (Goldman et al., 2023; Juenger et al., 2019). However, one study found that most leading cement-producing countries have substitute materials available in sufficient quantities to replace at least half of their current clinker usage (Shah et al., 2022). 

In terms of risks associated with alternative fuels, they can be subject to regional scarcity. Lack of available waste fuel in particular could risk non-waste biomass burning, leading to deforestation and high net emissions (de Puy Kamp, 2021). In addition, waste fuels can have varying compositions that can lead to different heats of combustion, kiln compatibility, or emitted pollutants (Griffiths et al., 2023). Finally, the use of waste products requires cement plants to be situated near industrial waste sources, risking low adoption for cement plants that are not located near a waste source. 

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Interactions with Other Solutions

Reinforcing

Lower-carbon cement will improve the effectiveness and enhance the net climate impact of any solutions that might require new construction. The embodied emissions from the cement and concrete used for new built structures or roads will be reduced.

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Technological advancements and increased adoption of efficient cement manufacturing equipment will improve the rate and cost of scaling similar high-efficiency machinery.

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Industrial electrification in cement plants will be faster and easier to adopt if the plants’ energy demands are lowered via reduced clinker production and more efficient processes.

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Competing

This solution uses biomass as a feedstock (raw material) for kiln fuel or as a source of ash for clinker substitues, including wood, food, crop residues, and municipal waste.  Because the total projected demand for biomass feedstocks for climate solutions exceeds the supply, not all of these solutions will be able to achieve their potential adoption. This solution is in competition with the following solutions for raw material:

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Dashboard

Solution Basics

Mt clinker avoided

t CO₂-eq (100-yr)/unit
0540,000690,000
units/yr
Current 980 01,0002,000
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 0.67 0.71
US$ per t CO₂-eq
-30
Gradual

CO₂

Solution Basics

Mt cement produced using alternative fuels

t CO₂-eq (100-yr)/unit
077,00096,000
units/yr
Current 300 06102,000
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 0.03 0.060.2
US$ per t CO₂-eq
-50
Gradual

CO₂

Solution Basics

GJ thermal energy input reduced from current levels/yr

t CO₂-eq (100-yr)/unit
0.085
units/yr
Current Not Determined 08.86×10⁸1.18×10⁹
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current Not Determined 0.0760.1
US$ per t CO₂-eq
-60
Gradual

CO₂

Trade-offs

Wider adoption of clinker material substitutes, alternative fuels, and process efficiency upgrades could generate new GHG emissions, including emissions stemming from the transportation of clinker material substitutes and alternative fuels as well as embodied emissions from manufacturing and installing new cement plant equipment. Nevertheless, the overall solution effectiveness is not expected to be significantly impacted. In some of the largest cement-producing countries, the emissions from transport of clinker material substitutes has been calculated to be an order of magnitude less than the emissions savings from the use of those substitutes in place of clinker (Shah et al., 2022). 

In terms of environmental impact, some clinker substitutes such as calcined clays and natural pozzolans can increase water use (Juenger et al., 2019; Snellings et al., 2023). Additionally, the use of biomass as an alternative fuel source could lead to trade-offs – such as increased water use and land use, or diminished resource availability – although the risk of this outcome is low since biomass for kiln fuels tends to be agricultural by-products or other waste (Clark et al., 2024; Georgiopoulou & Lyberatos, 2018). 

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Mt CO2-eq
< 2
2 - 4
4 - 6
6 - 8
8 - 10
> 10

Annual cement plant emissions, 2024

Cement production emissions are partly due to burning fossil fuels to run kilns and partly due to CO2 emissions associated with the chemistry of producing clinker, a key component of cement.

Sinha, A. and Crane, V. (2024). Manufacturing and industrial processes sector: Cement manufacturing emissions [Data set]. TransitionZero, Climate TRACE Emissions Inventory. Retrieved February 11, 2025, from Link to source: https://climatetrace.org

Mt CO2-eq
< 2
2 - 4
4 - 6
6 - 8
8 - 10
> 10

Annual cement plant emissions, 2024

Cement production emissions are partly due to burning fossil fuels to run kilns and partly due to CO2 emissions associated with the chemistry of producing clinker, a key component of cement.

Sinha, A. and Crane, V. (2024). Manufacturing and industrial processes sector: Cement manufacturing emissions [Data set]. TransitionZero, Climate TRACE Emissions Inventory. Retrieved February 11, 2025, from Link to source: https://climatetrace.org

Maps Introduction

There are no location-specific constraints to the effectiveness of the Improve Cement Production solution as there are for solutions dependent on climatic factors. However, there is geographic variation associated with current uptake of solutions and feasibility/expense of future uptake. Moreover, the distribution of cement-producing facilities around the world is non-uniform, thus the solution set naturally has the greatest applicability in regions with the greatest concentration of cement production. China and India have particularly high production of cement at 51% and 8% of global totals in 2024, respectively (Sinha & Crane, 2024).

Newer cement plants are more likely to have high thermal efficiencies, and the age of cement plants varies around the world, with average ages of cement plants less than 20 years in much of Asia, and greater than 40 years in much of the U.S. and Europe.

Uptake of alternative fuels is relatively high in Europe and low in the Americas.  

While use of clinker substitutes is in principle possible anywhere, the materials themselves are not readily available everywhere, thus transportation costs and associated emissions can place constraints on their viability (Shah et al., 2022).

Action Word
Improve
Solution Title
Cement Production
Current State Introduction

Our analysis of the current state of solutions for improved cement production included three separate approaches to reducing emissions: clinker substitution, alternative fuels, and process efficiency upgrades. Each approach had adoption units chosen based on data availability and consistency between calculated values. Figure 2 summarizes the units and conversions used for all approaches.

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Figure 2. Units of quantification used in the Current State, Adoption, and Impacts analyses below.

Approach Clinker substitution Alternative fuels Process efficiency upgrades
Effectiveness

t CO₂-eq abated/Mt clinker avoided*

t CO₂ abated/Mt cement produced*

 t CO₂-eq abated/Mt cement produced

t CO₂-eq abated/GJ thermal energy input**

t CO₂-eq abated/Mt cement produced**
Cost US$/Mt cement produced US$/Mt cement produced US$/Mt cement produced
Adoption Mt clinker avoided/yr Mt cement/yr produced using alternative fuels GJ thermal energy input saved/yr
Climate impact Gt CO₂-eq/yr Gt CO₂-eq/yr Gt CO₂-eq/yr

*Clinker substitution effectiveness was calculated in two different adoption units using the same source data. Effectiveness in t CO₂‑eq abated/Mt cement produced was used to calculate cost per climate impact. Effectiveness was converted to t CO₂‑eq abated/Mt clinker avoided using the clinker-to-cement ratio for each individual study in the analysis, and this was used to calculate climate impact.

**Process efficiency upgrades effectiveness in units of t CO₂‑eq abated/Mt cement produced was used to calculate cost per climate impact. Separately, a calculated fuel emission factor effectiveness in units of t CO₂‑eq abated/GJ thermal energy was used to quantify climate impact.

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Classification
Highly Recommended
Lawmakers and Policymakers
  • Hold cement manufacturers accountable for safety standards.
  • Regulate clinker substitution, alternative fuel usage, and process efficiency upgrades.
  • Set standards for low-carbon cement and reporting on embodied carbon for new projects.
  • Provide financial incentives such as grants, subsidies, and/or carbon taxes.
  • Set low-carbon cement standards for public procurement.
  • Implement building codes and standards that allow for the safe, tested use of low-clinker cement while accounting for regional variability in cement compositions.
  • When possible integrate low-carbon cement standards into industry standards such as LEED certification or CALGreen.
  • Increase investment in research and development of clinker material substitutes.
  • Promote a circular economy by creating reverse supply chains to collect industrial and biomass waste to be used as feedstocks for cement kilns and products.
  • Require labels for low-carbon products and materials.
  • Engage impacted communities and incorporate public feedback into policy design.
  • Ensure permit processes for mining or collecting clinker substitutes allow local supply chains to develop.
  • Integrate water management into policy planning when adopting new cement technologies, especially in drought-prone areas.

Further information:

Practitioners
  • Increase the fraction of clinker substitutes in cement, which will reduce production costs.
  • Use alternative fuels as manufacturing energy sources, ideally from renewable sources when possible, which will reduce production costs.
  • Upgrade equipment and production process to be more efficient, which will reduce production costs.
  • Invest in research and development for clinker material substitutes and process improvements.
  • Work to form national and regional industrial strategies for low-carbon cement.
  • Engage with local community members and use their feedback to create safer and healthier production facilities.
  • Increase transparency and reporting around energy usage, fuel composition, and the material composition of cement products.
  • Integrate water management safeguards when adopting new cement technologies, especially in drought-prone areas.
  • Join, create, or participate in partnerships or certification programs dedicated to improving cement production.

Further information:

Business Leaders
  • Source from low-carbon cement producers.
  • Advocate for low-carbon cement during project design and construction.
  • Promote concrete alternatives in high-profile projects.
  • Purchase, promote, and/or invest in local manufacturing and supply chains not only for materials and equipment used to make low-carbon cement, but also for low-carbon cementitious products.
  • Create off-take agreements for emerging cement technologies.
  • Create training and capacity-building programs for industry professionals related to the use and benefits of low-carbon cement and concrete.
  • Launch education and awareness campaigns that share case studies and pilot projects with industry media and other key stakeholders.
  • Leverage carbon markets to help subsidize the cost of low-carbon cement.
  • Work with governments and financial institutions to establish standards and incentives for utilizing low-carbon materials.

Further information:

Nonprofit Leaders
  • Assist with monitoring and reporting related to energy usage, fuel composition, and the material composition of cement products.
  • Help design policies and regulations that support low-carbon cement production.
  • Educate the public about the urgent need for low-carbon cement while showcasing its many benefits.
  • Encourage policymakers to create ambitious targets and regulations.
  • Encourage cement manufacturers to improve their practices.
  • Join, create, or participate in partnerships or certification programs dedicated to improving cement production.

Further information:

Investors
  • Invest in low-carbon cement producers, low-carbon cement research and development, and shared recycling infrastructure for cement materials.
  • Invest in supply chains for new clinker substitutes, alternative fuels, and technologies that improve production efficiency.
  • Encourage portfolio companies to produce low-carbon cement or source from low-carbon cement producers, noting that low-carbon retrofits will save money for producers.
  • Seek impact investment opportunities, such as low-interest loans for construction or renovation projects that use low-carbon cement, or favorable loans for entities that set low-carbon cement policies or targets.

Further information:

Philanthropists and International Aid Agencies
  • Set low-carbon cement standards for construction-related grants, loans, and awards.
  • Provide capital for local supply chains and the acquisition or production of clinker material substitutes.
  • Support global, national, and local policies that promote low-carbon cement use.
  • Explore opportunities to fund low-carbon cement start-ups.
  • Advance awareness of the public health and climate benefits of low-carbon cement.
  • Join, create, or participate in partnerships or certification programs dedicated to improving cement production.

Further information:

Thought Leaders
  • Provide technical assistance (e.g., circular economy design) to producers, government agencies, and other entities working to reduce cement emissions.
  • Help design policies and regulations that support the adoption of low-carbon cement.
  • Educate the public through campaigns emphasizing the urgent need to reduce cement production emissions.
  • Encourage policymakers to create more ambitious targets and regulations.
  • Pressure the cement industry to improve its production practices.
  • Join, create, or participate in partnerships or certification programs dedicated to improving cement production.

Further information:

Technologists and Researchers
  • Develop new separation technology for recycling cement material.
  • Assess new clinker substitutes and improve supply chains for known substitutes.
  • Improve the efficiency of processing technology and equipment.
  • Increase the safety of extraction, transport, handling, and processing of clinker material substitutes.
  • Develop on-site testing and reporting methods for tracking the energy use of manufacturing processes, fuel composition, and the material composition of cement products.
  • Examine and refine understandings of the potential revenue and price premiums of low-carbon cement products.

Further information:

Communities, Households, and Individuals
  • Purchase low-carbon cement and concrete products when possible.
  • Document your experiences if harmful cement production practices impact you. Share documentation of harmful cement production practices and/or other key messages with policymakers, the media, and your community.
  • Encourage policymakers to improve regulations related to cement production.
  • Support public education efforts to raise awareness about the urgent need to make cement production practices more environmentally sustainable.
  • Pressure the cement industry to improve its production practices.

Further information:

Sources
Evidence Base

Consensus of effectiveness in reducing cement industry emissions: High

The U.S. Department of Energy reports that the cement industry produces an estimated 7–8% of global CO₂ emissions (Goldman et al., 2023), so this is an important area to target. There is high scientific consensus that clinker substitution, alternative fuels, and process efficiency upgrades can be immediately and effectively implemented. Other emissions reduction strategies – including hydrogen kiln fuel, electrification, and carbon capture and storage technologies – have generated mixed scientific opinions on their potential for immediate impact and were not considered in this analysis. 

The U.S. Department of Energy (2022) highlighted cement as one of five high-emitting industries with potential for mitigation. The technologies identified as having the highest level of maturity and market readiness were energy efficiency measures, biomass and natural gas fuels, material efficiency measures, and blended-material cements. 

An extensive review of industrial decarbonization points to four technologies that could be implemented in the near term across global industries: electrification, material efficiency, energy efficiency, and circularity (Rissman et al., 2020). The European Cement Research Academy (2022) classified the three cement industry approaches considered in this solution – clinker substitution, alternative fuels, and process efficiency upgrades – as meeting the highest technology readiness level.

Goldman et al. (2023) identified clinker substitution, alternative fuels, and efficiency improvements as deployable today, estimating that these three approaches could abate 30% of U.S. cement industry emissions by 2030. Habert et al. (2020) proposed technologies that could reduce emissions up to 50% in the next few decades, including “cement improvements” of supplementary clinker materials, alternative fuels, and more efficient technologies. The IEA (2018) estimated that clinker material replacement, alternative fuels, and efficiency improvements could provide 37%, 12%, and 3% of cement emissions savings by 2050, respectively.

The results presented in this document summarize findings from two reviews and meta-analyses, eight original studies, nine reports, and several data sets reflecting current evidence from 33 countries, primarily high cement-producing countries in North America, Europe, and Asia. We recognize this limited geographic scope creates bias, and hope this work inspires research and data sharing on this topic in underrepresented regions.

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Improve Landfill Management

Submitted by Drawdown Admin on
Sector
Industry, Materials & Waste
Mode
Cut Emissions
Cluster
Cut Fugitive Emissions
Image
Methane tap valve from a landfill
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Summary

Landfill management is the process of reducing methane emissions from landfill gas (LFG). As bacteria break down organic waste in an environment without oxygen, they produce methane and release it into the atmosphere if there are no controls in place. This solution focuses on two methane abatement strategies: 1) methane capture/use/destruction and 2) biocovers. When methane is used or destroyed it is converted into CO₂ (Garland et al., 2023).

Income & work,Health,Equality
Air quality
Description for Social and Search
Improve Landfill Management is a Highly Recommended climate solution. It focuses on abating landfill methane through methane capture and biocovers.
Overview

Landfill management relies on several practices and technologies that prevent methane from being released into the atmosphere. When organic material is broken down, it creates LFG, which usually is half methane and half CO₂, and water vapor (U.S. Environmental Protection Agency [U.S. EPA], 2024a). Methane that is directly released into the atmosphere has a GWP of 81 over a 20-yr basis and a GWP of 28 over a 100-yr basis (Intergovernmental Panel on Climate Change [IPCC], 2023). This means methane is 81 times more effective at trapping heat than CO₂. Because methane is a short-lived climate pollutant that has a much stronger warming effect than CO₂ over a given time period, abating methane will have a relatively large near-term impact on slowing global climate change (International Energy Agency [IEA], 2023). LFG contains trace amounts of oxygen, nitrogen, sulfides, hydrogen, and other organic compounds that can negatively affect nearby environments with odors, acid rain, and smog (New York State Government, 2024).

Methods for reducing methane emissions can be put into two broad strategies, with Figure 1 illustrating in which parts of a landfill the strategies can be used (Garland et al., 2023):

GCCS and methane capture utilizes pipes to route LFG to be used as an energy source or to flare. The gas can be used on-site for landfill equipment or refined into biomethane and sold; unrefined LFG can also be sold to local utilities or industries for their own use. In areas where electricity generation is carbon intensive, the LFG can help to reduce local emissions by displacing fossil fuels. Methane that cannot be used for energy is burned in a flare during system downtime or at the end of the landfill life, when LFG production has decreased and collecting it no longer makes economic sense. High-efficiency (enclosed) flares have a 99% methane destruction rate. Open flares can be used but research from Plant et al. (2022) has found that the methane destruction rate in practice is much lower than the 90% value the U.S. EPA assumes. 

Biocovers are a type of landfill cover designed to promote bacteria that convert methane to CO₂ and water. Biocovers have an organic layer that provides an environment for the bacteria to grow and a gas distribution layer to separate the landfill waste from the organic layer. Non-biocover landfill covers – made with impermeable material like clay or synthetic materials – can also be used to prevent methane from being released. The methane oxidation from these covers will be minimal – they mostly serve to limit LFG from escaping – but they can then be used in conjunction with GCCS to improve gas collection. Landfills also use daily and interim landfill covers. It is important to note that studies on biocover abatement potential and cost are limited and biocovers may not be appropriate for all situations.

Leak Detection and Repair (LDAR) involves regularly monitoring for methane leaks and modifying or replacing leaking equipment. LDAR does not directly reduce emissions but is used to determine where to apply the above technology and practices and is considered a critical part of methane abatement strategies. Methane can be monitored through satellites, drones, continuous sensors, or on-site walking surveys (Carbon Mapper, 2024). LDAR is an important step in identifying where methane escapes from the gas collection infrastructure or landfill cover. Quick repairs help reduce GHG emissions while allowing more methane to be used for energy or fuel. The Appendix shows where methane can escape from landfills.

Figure 1. Areas where different on-site landfill methane abatement strategies can take place. Source: Garland et al. (2023)

Landfill Methane: Key Problems and Solutions diagram

Source: Garland E., Alves O., Frankiewicz T., & Ayandele E. (2023). Mitigating landfill methane. RMI. 

Abichou, T. (2020). Using methane biological oxidation to partially finance sustainable waste management systems and closure of dumpsites in the Southern Mediterranean region. Euro-Mediterranean Journal for Environmental Integration. Link to source: https://doi.org/10.1007/s41207-020-00157-z 

Auth, K., & Kincer, J. (2022). Untangling ‘stranded assets’ and ‘carbon lock-in.’ Energy for Growth Hub. Link to source: https://energyforgrowth.org/article/untangling-stranded-assets-and-carbon-lock-in/ 

Ayandele, E., Bodas, J., Gautam, S., & Velijala, V. (2024c). Sustainable organic waste management: A playbook for Lucknow, India. RMI. Link to source: https://www.teriin.org/policy-brief/sustainable-organic-waste-management-playbook-lucknow-india 

Ayandele, E., Bodas, J., Krishnakumar, A., & Orakwe, L. (2024b). Mitigating methane emissions from municipal solid waste: A playbook for Lagos, Nigeria. RMI. Link to source: https://rmi.org/insight/waste-methaneassessment-platform/

Ayandele, E., Frankiewicz, T., & Garland, E. (2024a). Deploying advanced monitoring technologies at US landfills. RMI. Link to source: https://rmi.org/wp-content/uploads/dlm_uploads/2024/03/wasteMAP_united_states_playbook.pdf

Ayandele, E., Frankiewicz, T., & Wu, Y. (2024d). A playbook for municipal solid waste methane mitigation. RMI. Link to source: https://rmi.org/wp-content/uploads/dlm_uploads/2024/03/wastemap_global_strategy_playbook.pdf

Barton, D. (2020). Fourth five-year review report for Fresno municipal sanitary landfill superfund site Fresno county, California. U.S. Environmental Protection Agency. Link to source: https://semspub.epa.gov/work/09/100021516.pdf 

Brender, J. D., Maantay, J. A., Chakraborty, J. (2011). Residential proximity to environmental hazards and adverse health outcomes. American Journal of Public Health, 101(S1). Link to source: https://pmc.ncbi.nlm.nih.gov/articles/PMC3222489/pdf/S37.pdf 

Cai, B., Lou, Z., Wang, J., Geng, Y., Sarkis, J., Liu, J., & Gao, Q. (2018). CH4 mitigation potentials from China landfills and related environmental co-benefits. Science Advances, 4(7). Link to source: https://doi.org/10.1126/sciadv.aar8400 

Carbon Mapper (2024, March 28). Study finds landfill point source emissions have an outsized impact and opportunity to tackle U.S. waste methane. Link to source: https://carbonmapper.org/articles/studyfinds-landfill 

Casey, J. A., Cushing, L., Depsky, N., & Morello-Frosch, R. (2021). Climate justice and California's methane superemitters: Environmental equity assessment of community proximity and exposure intensity. Environmental Science & Technology, 55(21), 14746–14757. Link to source: https://doi.org/10.1021/acs.est.1c04328 

City of Saskatoon. (2023). Landfill gas collection & power generation system. Retrieved September 2, 2024. Link to source: https://www.saskatoon.ca/services-residents/power-water-sewer/saskatoon-light-power/sustainable-electricity/landfill-gas-collection-power-generation-system 

DeFabrizio, S., Glazener, W., Hart, C., Henderson, K., Kar, J., Katz, J., Pratt, M. P., Rogers, M., Ulanov, A., & Tryggestad, C. (2021). Curbing methane emissions: How five industries can counter a major climate threat. McKinsey Sustainability. Link to source: https://www.mckinsey.com/~/media/mckinsey/business%20functions/sustainability/our%20insights/curbing%20methane%20emissions%20how%20five%20industries%20can%20counter%20a%20major%20climate%20threat/curbing-methane-emissions-how-five-industries-can-counter-a-major-climate-threat-v4.pdf 

Dobson, S., Goodday, V., & Winter, J. (2023). If it matters, measure it: A review of methane sources and mitigation policy in Canada. International Review of Environmental and Resource Economics, 16(3-4), 309–429. Link to source: https://doi.org/10.1561/101.00000146

Fries, J. (2020, March 26). Unique landfill gas solution found. Penticton Herald. Link to source: https://www.pentictonherald.ca/news/article_874b5c9c-6fb5-11ea-87ce-2b2aedf77300.html 

Garland E., Alves O., Frankiewicz T., & Ayandele E. (2023). Mitigating landfill methane. RMI. Link to source: https://rmi.org/wp-content/uploads/dlm_uploads/2023/06/landfill_monitoring_memo_series.pdf 

Global Climate & Health Alliance. (2024). Methane & health. Retrieved September 24, 2024. Link to source: https://climateandhealthalliance.org/initiatives/methane-health/ 

Global Methane Initiative. (2022). Policy maker’s handbook for measurement, reporting, and verification in the biogas sector. Link to source: https://www.globalmethane.org/resources/details.aspx?resourceid=5182

Global Methane Initiative (2024). 2023 accomplishments in methane mitigation, recovery, and use through U.S.-supported international efforts. Link to source: https://www.epa.gov/gmi/us-government-global-methane-initiative-accomplishments 

Global Methane Pledge (2023). Lowering organic waste methane initiative (LOW-Methane). Retrieved March 6, 2025. Link to source: https://www.globalmethanepledge.org/news/lowering-organic-waste-methane-initiative-low-methane 

Gómez-Sanabria, A., & Höglund-Isaksson, L. (2024). A comprehensive model for promoting effective decision-making and sustained climate change stabilization for South Africa. International Institute for Applied Systems Analysis. Link to source: https://pure.iiasa.ac.at/id/eprint/19897/1/Final_Report_SAFR.pdf

Government of Canada. (2024). Canada gazette, part I, volume 158, number 26: Regulations respecting the reduction in the release of methane (waste sector). Retrieved September 2, 2024. Link to source: https://canadagazette.gc.ca/rp-pr/p1/2024/2024-06-29/html/reg5-eng.html 

Industrious Labs. (2024a). The hidden cost of landfills. Link to source: https://cdn.sanity.io/files/xdjws328/production/657706be7f29a20fe54692a03dbedce8809721e8.pdf 

Industrious Labs. (2024b). Turning down the heat: How the U.S. EPA can fight climate change by cutting landfill emissions. Link to source: https://cdn.sanity.io/files/xdjws328/production/b562620948374268b8c6da61ec1c44960a8d5879.pdf 

Intergovernmental Panel on Climate Change. (2023). Sixth assessment report (AR6). Link to source: https://www.ipcc.ch/assessment-report/ar6/ 

International Energy Agency. (2021). Global methane tracker 2021: Methane abatement and regulation. Link to source: https://www.iea.org/reports/methane-tracker-2021/methane-abatement-and-regulation 

International Energy Agency. (2023). Net zero roadmap: A global pathway to keep the 1.5℃ goal in reach - 2023 update. Link to source: https://www.iea.org/reports/net-zero-roadmap-a-global-pathway-to-keep-the-15-0c-goal-in-reach 

International Energy Agency. (2025). Methane tracker: Data tools. Link to source: https://www.iea.org/data-and-statistics/data-tools/methane-tracker 

IPCC (2006). 2006 IPCC guidelines for national greenhouse gas inventories volume 5 waste. Link to source: https://www.ipcc-nggip.iges.or.jp/public/2006gl/vol5.html   

Krause, M. Kenny, S., Stephensons, J. & Singleton, A (2023). Food waste management: Quantifying methane emissions from landfilled food waste. U.S. Environmental Protection Agency. Link to source: https://www.epa.gov/system/files/documents/2023-10/food-waste-landfill-methane-10-8-23-final_508-compliant.pdf

Malley, C. S., Borgford-Parnell, N. Haeussling, S., Howard, L. C., Lefèvre E. N., & Kuylenstierna J. C. I. (2023). A roadmap to achieve the global methane pledge. Environmental Research: Climate, 2(1). Link to source: https://doi.org/10.1088/2752-5295/acb4b4 

Martin Charlton Communications. (2020). Features: Landfill biocovers. APEGS. Link to source: https://www.apegs.ca/features-landfill-biocovers 

Martuzzi, M., Mitis, F., & Forastiere, F. (2010). Inequalities, inequities, environmental justice in waste management and health. European Journal of Public Health, 20(1), 21–26. Link to source: https://doi.org/10.1093/eurpub/ckp216 

MethaneSAT. (n.d.). Solving a crucial climate challenge. Retrieved September 2, 2024. Link to source: https://www.methanesat.org/satellite/ 

Nesser, H., Jacob, D. J., Maasakkers, J. D., Lorente, A., Chen, Z., Lu, X., Shen, L., Qu, Z., Sulprizio, M. P., Winter, M., Ma, S., Bloom, A. A., Worden, J. R., Stavins, R. N., & Randles, C. A. . (2024). High-resolution US methane emissions inferred from an inversion of 2019 TROPOMI satellite data: Contributions from individual states, urban areas, and landfills. Atmospheric Chemistry and Physics, 24, 5069–5091. Link to source: https://doi.org/10.5194/acp-24-5069-2024 

New York State Government. (2024). Important things to know about landfill gas. Retrieved September 3, 2024. Link to source: https://www.health.ny.gov/environmental/outdoors/air/landfill_gas.htm 

Nisbet, E. G., Fisher, R. E., Lowry, D., France, J. L., Allen, G., Bakkaloglu, S., Broderick, T. J., Cain, M., Coleman, M., Fernandez, J., Forster, G., Griffiths, P. T., Iverach, C. P., Kelly, B. F. J., Manning, M. R., Nisbet-Jones, P. B. R., Pyle, J. A., Townsend-Small, A., al-Shalaan, A., Warwick, N., & Zazeri, G. (2020). Methane mitigation: Methods to reduce emissions,on the path to the Paris agreement. Review of Geophysics, 58(1). Link to source: https://doi.org/10.1029/2019RG000675 

Ocko, I. B., Sun, T., Shindell, D., Oppenheimer, M. Hristov, A. N., Pacala, S. W., Mauzerall, D. L., Xu, Y. & Hamburg, S. P. (2021). Acting rapidly to deploy readily available methane mitigation measures by sector can immediately slow global warming. Environmental Research, 16(5). Link to source: https://doi.org/10.1088/1748-9326/abf9c8 

Olaguer, E. P. (2021). The potential ozone impacts of landfills. Atmosphere, 12(7), 877. Link to source: https://doi.org/10.3390/atmos12070877 

Plant, G., Kort, E. A., Brandt, A. R., Chen, Y., Fordice, G., Negron, A. M. G., Schwietzke, S., Smith, M., & Zavala-araiza, D. (2022). Estimates of solid waste disposal rates and reduction targets for landfill gas emissions. Science, 377(6614), 1566–1571. Link to source: https://doi.org/10.1126/science.abq0385 

Powell J. T., Townsend, T. G., & Zimmerman, J. B. (2015). Estimates of solid waste disposal rates and reduction targets for landfill gas emissions. Nature Climate Change, 6, 162-165. Link to source: https://www.nature.com/articles/nclimate2804

Raniga, K., (2024). Waste Sector: Estimating CH4 Emissions from Solid Waste Disposal Sites [Data set]. WattTime, Climate TRACE Emissions Inventory. Retrieved April 21, 2025, from Link to source: https://climatetrace.org

SaveOnEnergy. (2024). Landfills: The truths about trash dumps by the numbers. Retrieved September 2, 2024, from Link to source: https://www.saveonenergy.com/resources/landfill-statistics/ 

Scarapelli, T. R., Cusworth, D. H., Duren, R. M., Kim, J., Heckler, J., Asner, G. P., Thoma, E., Krause, M. J., Heins, D., & Thorneloe, S. (2024). Investigating major sources of methane emissions at US landfills. Environmental Science & Technology. 58(29). Link to source: https://doi.org/10.1021/acs.est.4c07572

Scharff, H. Soon, H., Taremwa, S. R., Zegers, D., Dick, B., Zanon, T. V. B., & Shamrock, J. (2023). The impact of landfill management approaches on methane emissions. Waste Management & Research. Link to source: https://doi.org/10.1177/0734242X231200742 

Scheutz, C., Pedersen, R. B., Petersen, P. H., Jørgensen, J. H. B., Ucendo, I. M. B., Mønster, J. G., Samuelsson, J., Kjeldsen, P. (2014). Mitigation of methane emission from an old unlined landfill in Klintholm, Denmark using a passive biocover system. Waste Management. 34(7), 1179–1190. Link to source: https://doi.org/10.1016/j.wasman.2014.03.015 

Siddiqua, A., Hahladakis, J.N. & Al-Attiya, W.A.K.A. (2022). An overview of the environmental pollution and health effects associated with waste landfilling and open dumping. Environmental Science and Pollution Research 29, 58514–58536 Link to source: https://doi.org/10.1007/s11356-022-21578-z 

Sperling Hansen Associates (2020). 7 Mile landfill operational biocover study. Link to source: https://www.rdmw.bc.ca/media/2020%2003%2017%207Mile%20Landfill%20Operational%20Biocover%20Study.pdf 

Stern, J. C., Chanton, J., Ahicou, T., Powelson, D., Yuan, L., Escoriza, S. & Bogner, J.. (2007). Use of a biologically active cover to reduce landfill methane emissions and enhance methane oxidation. Waste Management 27(9), 1248–1258. Link to source: https://doi.org/10.1016/j.wasman.2006.07.018 

Stone, E. (2023, September 7). Landfills: 'Zombie' landfills emit tons of methane decades after shutting down. Here's why that's a big problem. LAist. Link to source: https://laist.com/news/climate-environment/zombie-landfills-emit-tons-of-methane-decades-after-shutting-down-heres-why-thats-a-big-problem 

Sweeptech. (2022). What is a landfill site’s environmental impact?. Retrieved March 7, 2025, from Link to source: https://www.sweeptech.co.uk/what-is-a-landfill-site-and-how-does-landfill-impact-the-environment/#:~:text=The%20average%20size%20of%20a,for%20these%20massive%20waste%20dumps. 

Tangri, N. (2010). Respect for recyclers: Protecting the climate through zero waste. Gaia. Link to source: https://www.no-burn.org/wp-content/uploads/2021/11/Respect-for-Recyclers-English_1.pdf 

Towprayoon, S., Ishigaki, T., Chiemchaisri, C., & Abdel-Aziz, A. O. (2019). Chapter 3: Solid waste disposal. In 2019 refinement to the 2006 IPCC guidelines for national greenhouse gas inventories. International Panel on Climate Change. Link to source: https://www.ipcc-nggip.iges.or.jp/public/2019rf/pdf/5_Volume5/19R_V5_3_Ch03_SWDS.pdf

Trashcans Unlimited. (2022). Biggest landfill in the world. Retrieved March 7, 2025. Link to source: https://trashcansunlimited.com/blog/biggest-landfill-in-the-world/ 

UN Environment Program. (2021). Global methane assessment: Benefits and costs of mitigating methane emissions. Link to source: https://www.unep.org/resources/report/global-methane-assessment-benefits-and-costs-mitigating-methane-emissions 

U.S. Environmental Protection Agency. (2019). Global non-CO2 greenhouse gas emission projections & mitigation 2015–2050. Link to source: https://www.epa.gov/ozone-layer-protection/transitioning-low-gwp-alternatives-residential-and-commercial-air

U.S. Environmental Protection Agency. (2024a). Basic information about landfill gas. Retrieved September 2, 2024. Link to source: https://www.epa.gov/lmop/basic-information-about-landfill-gas 

U.S. Environmental Protection Agency. (2024b). Benefits of landfill gas energy projects. Retrieved September 23, 2024. Link to source: https://www.epa.gov/lmop/benefits-landfill-gas-energy-projects 

U.S. Environmental Protection Agency. (2025). Accomplishments of the landfill methane outreach program. Retrieved March 5, 2025. Link to source: https://www.epa.gov/lmop/accomplishments-landfill-methane-outreach-program 

Van Dingenen, R., Crippa, M., Maenhout, G., Guizzardi, D., & Dentener, F. (2018). Global trends of methane emissions and their impacts on ozone concentrations. European Commission. Link to source: https://op.europa.eu/en/publication-detail/-/publication/c40e6fc4-dbf9-11e8-afb3-01aa75ed71a1/language-en 

Vasarhelyi, K. (2021, April 15). The hidden damage of landfills. University of Colorado Boulder. Link to source: https://www.colorado.edu/ecenter/2021/04/15/hidden-damage-landfills#:~:text=The%20average%20landfill%20size%20is,liners%20tend%20to%20have%20leaks 

Waste Today. (2019, June 26). How landfill covers can help improve operations. Retrieved April 13, 2025, from Link to source: https://www.wastetodaymagazine.com/news/interim-daily-landfill-covers/ 

Zhang, T. (2020, May 8). Landfill earth: A global perspective on the waste problem. Universitat de Barcelona. Link to source: https://diposit.ub.edu/dspace/bitstream/2445/170328/1/Landfill%20Eart.%20A%20Global%20Perspective%20on%20the%20Waste%20Problem.pdf 

Credits

Lead Fellow

  • Jason Lam

Contributors

  • Yusuf Jameel, Ph.D.

  • Daniel Jasper

  • James Gerber, Ph.D.

  • Alex Sweeney

Internal Reviewers

  • Erika Luna

  • Paul C. West, Ph.D.

  • Amanda D. Smith, Ph.D.

  • Aiyana Bodi

  • Hannah Henkin

  • Ted Otte

Effectiveness

According to the IPCC, preventing 1 Mt of emitted methane avoids 81.2 Mt CO₂‑eq on a 20-yr basis and 27.9 Mt CO₂‑eq on a 100-yr basis (Smith et al., 2021, Table 1). If the methane is burned (converted into CO₂), the contribution to GHG emissions is still less than that of methane released directly into the atmosphere. Methane abatement can immediately limit future global climate change because of methane’s outsized impact on global temperature change, especially when looking at a 20-yr basis.

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Table 1. Effectiveness at reducing emissions.

Unit: t CO₂‑eq/Mt of methane abated

100-yr GWP 27,900,000
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Cost

To abate 1 Mt of methane, GCCS and methane capture have an initial cost of around US$410 million, an operating cost of roughly US$191 million, and revenue in the neighborhood of US$383 million. The net savings over a 30-yr amortization period is US$179 million. This means capturing and selling landfill methane will be a net economic gain for most landfill operators. We included LDAR operating costs in the overall operating costs for GCCS and methane use/destruction, although LDAR can be used prior to installation or with other strategies such as biocovers. We split the median costs for GCCS and methane use/destruction between 20-yr and 100-yr GWP (Table 2a).

Biocovers have an initial cost to abate 1 Mt of methane around US$380 million, operating costs of roughly US$0.4 million, and revenue of about US$0 million, and an overall net cost over a 30-yr amortization period of US$13 million. This means that using biocovers to abate landfill methane has a net cost. If a carbon credit system is in place, biocovers can recoup the costs or generate profits. Biocovers are reported to have lower installation and operation costs than GCCS because they are simpler to install and maintain, and can be used where local regulations might limit a landfill operator’s ability to capture and use methane (Fries, 2020). Table 2b shows that the median costs for biocovers are split between 20-yr and 100-yr GWP.

We found very limited data for the baseline scenario, which follows current practices without methane abatement. We considered the baseline costs to be zero for initial costs, operational costs, and revenue because landfills without management – such as open landfills or sanitary landfills with no methane controls – release methane as part of their regular operations, do not incur added maintenance or capital costs, and lack any energy savings from capturing and using methane.

Few data were available to characterize the initial costs of implementing landfill methane capture. We referenced reports from Ayandele et al. (2024a), City of Saskatoon (2023), DeFabrizio et al. (2021), and Government of Canada (2024), but the context and underlying assumptions costs were not always clear. 

Landfills are typically 202–243 ha (Sweeptech, 2022); however, the size can vary greatly, with the world’s largest landfill covering 890 ha (Trashcans Unlimited, 2022). Because larger landfills make more methane, facility size helps determine which methane management strategies make the most sense. We assumed the average landfill covered 243 ha when converting costs to our common unit. 

Data on revenues from the sale of collected LFG are also limited. We found some reports of revenue generated at a municipal level or monetized benefits from GHG emission reductions priced according to a social cost of methane or carbon credit system (Abichou, 2020; Government of Canada, 2024). These values may not apply at a global scale, especially when the credits are supported by programs such as the United States’ use of Renewable Identification Numbers.

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Table 2. Cost per unit climate impact.

Unit: 2023 US$/t CO₂‑eq

Median (100-yr basis) -6.42
Median (20-yr basis) -2.21

Unit: 2023 US$/t CO₂‑eq

Median (100-yr basis) 0.47
Median (20-yr basis) 0.16
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Learning Curve

Landfill GCCSs are mature; we do not foresee declining implementation costs for these solutions due to extensive use of the same installation equipment and materials in other industries and infrastructure. Automation of GCCS settings and monitoring may improve efficiencies, but installation costs will stay largely the same. 

Landfill covers are a mature technology, having been used to control odors, fires, litter, and scavenging since 1935 (Barton, 2020). Biocover landfill cover costs could decrease as recycled organic materials are increasingly used in their construction. It is not clear how the cost of biocovers might decrease as adoption grows. 

Though LDAR might provide gains around efficiencies, little research offers insights here.

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Speed of Action

Speed of action refers to how quickly a climate solution physically affects the atmosphere after it is deployed. This is different from speed of deployment, which is the pace at which solutions are adopted.

At Project Drawdown, we define the speed of action for each climate solution as emergency brake, gradual, or delayed.

Improve Landfill Management is an EMERGENCY BRAKE climate solution. It has the potential to deliver a more rapid impact than gradual and delayed solutions. Because emergency brake solutions can deliver their climate benefits quickly, they can help accelerate our efforts to address dangerous levels of climate change. For this reason, they are a high priority.

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Caveats

Approximately 61% of methane generated from food waste happens within 3.6 years of being landfilled (Krause, et al., 2023). In the United States, the EPA requires GCCS to be installed after five years of the landfill closing, meaning that much of the food waste methane will evade GCCS before it is installed (Industrious Labs, 2024b). In contrast, biocovers can quickly (up to three months) reduce methane emissions once the bacteria have established (Stern et al., 2007). GCCS and biocovers should be installed as soon as possible to capture as much of the early methane produced from food waste. Due to unstable methane production during early- and end-of-life gas production, low-calorific flares or biocovers may be needed to destroy any poor-quality gas that has collected. Strategies that prevent organic waste from being deposited at landfills are captured in other Project Drawdown solutions: Deploy Methane Digesters, Increase Composting, and Reduce Food Loss & Waste.

The effectiveness of landfill management depends on methane capture and destruction efficiency. The U.S. EPA previously assumed methane capture efficiency to be 75% and then revised it to 65%; however, the actual recovery rate in the United States is closer to 43% (Industrious Labs, 2024b). 

Our assessment does not include the impact of the CO₂ created from the destruction of methane.

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Current Adoption

We found little literature quantifying the current adoption of LFG methane abatement. We estimate that methane capture/use/destruction accounts for approximately 1.6 Mt/yr of abated global methane. 

We did not find unaggregated data about current adoption of biocovers or global data for landfill methane abatement that we could use to allocate the contribution to each landfill methane abatement strategy. A large portion of data for current adoption is from sources focused on landfills in the United States. Around 70 Mt of methane is currently being emitted globally from landfills in 2024 (IEA, 2025; Ocko et al., 2021). 

Table 3a shows the statistical ranges among the sources we found for current adoption of methane capture/use/destruction. We were not able to find sources measuring the current adoption of biocovers and the amount of methane abated and therefore report it as not determined (Table 3b)."

The U.S. EPA’s Landfill Methane Outreach Program helps reduce methane emissions from U.S. landfills. The program has worked with 535 of more than 3,000 U.S. landfills (U.S. EPA, 2024; Vasarhelyi, 2021). Global Methane Initiative (GMI) members abated 4.7 Mt of methane from 2004 to 2023 (GMI, 2024). Because GMI members cover only 70% of human-caused methane emissions overall – including wastewater and agricultural emissions this is an overestimate of current landfill methane abatement. Holley et al. (2024) determined that while some methane abatement was occuring in Mexico, only 0.13 Mt of methane was abated from 2018 to 2020, which is about 12% of Mexico’s 2021 solid waste sector methane emissions. India and Nigeria recently installed some methane capture/use/destruction systems, but these are excluded from our analysis due to unclear data (Ayandele et al., 2024b; Ayandele et al., 2024c). Industrious Labs (2024b) found that GCCS were less common than expected – the U.S. EPA assumes a 75% gas recovery rate for well-managed landfills. A study on Maryland landfills found that only half had GCCS in place, with an average collection efficiency of 59% (Industrious Labs, 2024b). 

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Table 3. Current (2023) adoption level.

Unit: Mt/yr methane abated

25th percentile 1.26
Mean 1.64
Median (50th percentile) 1.59
75th percentile 2.00

Unit: Mt/yr methane abated

25th percentile not determined
Mean not determined
Median (50th percentile) not determined
75th percentile not determined
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Adoption Trend

Few studies explicitly quantify the adoption of methane abatement technologies over time; we estimated the adoption trend to be 0.22 Mt/yr of methane abated – mainly from methane capture/use/destruction. We were not able to find unaggregated data for the adoption trend of biocovers, so we estimated adoption from the U.S. EPA (2024), GMI (2024), Industrious Labs (2024b), and Van Dingenen et al. (2018). The U.S. EPA (2024) provided adoption data for a limited number of U.S. landfills that showed increasing methane abatement 2000–2013, a plateau 2013–2018, and slower progress 2018–2023 (Figure 2).

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GMI (2024) show a gradual increase in methane abatement 2011–2022. However, these data do not differentiate landfill methane abatement from other abatement opportunities, and even include wastewater systems and agriculture. When the GMI (2024) data are used to estimate adoption trends, they result in an overestimate. Van Dingenen et al. (2018) attributed a decreasing trend in landfill methane emissions 1990–2012 to landfill regulations implemented in the 1990s. Table 4a shows statistical ranges among the sources we found for the adoption trend of landfill methane strategies. Due to a lack of sources, we assume a zero value for the adoption trend of biocovers (and the amount of methane abated) as shown in Table 4b.

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Table 4. 2011–2022 adoption trend.

Unit: Mt/yr methane abated

25th percentile 0.05
Mean 0.38
Median (50th percentile) 0.22
75th percentile 0.54

Unit: Mt/yr methane abated

25th percentile 0
Mean 0
Median (50th percentile) 0
75th percentile 0
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Adoption Ceiling

GCCS and methane capture have an estimated adoption ceiling of 70 Mt/yr of methane abated based on the IEA’s (2025) estimate for methane emissions from the landfill waste sector. We assumed that current landfill methane emissions would remain the same into the future with no changes in waste produced or waste diversion employed.

Biocovers have an estimated adoption ceiling of 70 Mt/yr of methane based on the IEA’s (2025) estimate for methane emissions from the landfill waste sector. We assumed that current landfill methane emissions would remain the same into the future with no changes in waste produced or waste diversion employed.

The maximum possible abatement of LFG methane critically depends on the efficiency of the abatement technology; Powell et al. (2015) found that closed landfills (those not actively receiving new waste) were 17% more efficient than open landfills. Even so, research from Nesser et al. (2024) found that the gas capture efficiency among United States landfills was significantly lower than U.S. EPA assumptions – closer to 50% rather than 75%. Industrious Labs (2024b) found that landfill methane emissions could be reduced by up to 104 Mt of methane 2025–2050. Using biocovers and installing GCCS earlier (with consistent operation standards) may help reduce emissions throughout the landfill’s lifespan. Tables 5a and 5b show the adoption ceiling for GCCS and methane use/destruction strategies, and for biocovers when used separately.

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Table 5. Adoption ceiling.

Unit: Mt/yr methane abated

Median (50th percentile) 70

Unit: Mt/yr methane abated

Median (50th percentile) 70
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Achievable Adoption

The amount of methane that can be abated from landfills is highly uncertain due to the difficulty in quantifying where and how much methane is emitted and how much of those emissions can be abated. 

GCCS and methane capture strategies have an achievable adoption range of 5–35 Mt/yr of methane (Table 6a). These values are aligned with estimates from DeFabrizio et al. (2021) and Scharff et al. (2023) for landfill methane abatement. 

Biocovers have an achievable adoption range of 35–57 Mt/yr of methane (Table 6b). This value is aligned with estimates of biocover gas destruction efficiency from Duan et al. (2022) and Scheutz et al. (2014). 

The use of these methane abatement strategies would still release around 13–65 Mt/yr of methane into the atmosphere (IEA, 2025). The amount of methane abated from both GCCS and methane use/destruction strategies and biocovers will vary with what kind of waste reduction and organic diversion is used (which can increase or decrease depending on the amount of organics sent to landfills). 

We referenced CCAC (2024), U.S. EPA (2011), Fries (2020), Industrious Labs (2024b), Lee et al. (2017), and Sperling Hansen (2020) when looking at the achievable adoption for global landfill methane abatement. Several resources focused on landfills in Canada, Denmark, South Korea, and the United States. We based the adoption achievable for biocovers only on sources that include the percentage of gas capture (destruction) efficiency over landfill sites. We exclude studies that include the percentage of biogas oxidized because they focus on specific areas where biocovers were applied. It is important to note that biocovers do not capture methane – they destroy it through methane oxidation. In addition, biocovers’ gas capture efficiency will not reach its optimal rate until the bacteria establishes. It may take up to three months (Stern et al., 2007) for methane oxidation rates to stabilize, and – because environmental changes can impact the bacteria’s methane oxidation rate – the value presented here likely overestimates biocover methane abatement potential in practice. Stern et al. (2007) found that biocovers can be a methane sink and oxidation rates of 100% have been measured at landfills. 

Few studies have examined how methane abatement is affected when all strategies are combined. A single landfill’s total methane abatement would likely increase with each added strategy, the total methane abatement is not expected to be additive between the strategies. For example, If a GCCS system can capture a large portion of LFG methane, then adding a biocover to the same landfill will play a reduced role in methane abatement. The values presented do not consider which geographies are best suited for specific methane abatement strategies. Compared with reality, those values may appear generous. 

Long-term landfill methane abatement will be necessary to manage emissions from previously deposited organic waste. Strong regulations for waste management can encourage methane abatement strategies at landfills and/or reduce the amount of organics sent their way. The infrastructure for these methane abatement strategies can still be employed in geographies without strong regulations. Tables 6a and 6b show the statistical low and high achievable ranges for GCCS and methane use/destruction strategies and for biocovers (when used separately) based on different reported sources for adoption ceilings.

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Table 6. Range of achievable adoption levels.

Unit: Mt/yr methane abated

Current adoption 1.60
Achievable – low 4.50
Achievable – high 34.78
Adoption ceiling 69.56

Unit: Mt/yr methane abated

Current adoption not determined
Achievable – low 35.13
Achievable – high 57.04
Adoption ceiling 69.56
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Landfill methane abatement has a high potential for climate impact. 

GCCS and methane capture strategies can significantly reduce landfill GHG emissions (Table 7a).

Biocovers can be a useful strategy for controlling LFG methane (Table 7b) because they can oxidize methane in areas where GCCS and methane use/destruction strategies are not applicable. In addition, this strategy can help destroy methane missed from GCCS and even remove methane from the atmosphere (Stern et al., 2007). The lower cost for installation and operation when compared to installing GCCS systems and increased applicability at landfills large and small are encouraging factors for broadening their use around the world. 

LDAR can help identify methane leaks,allowing for targeted abatement (Industrious Labs, 2024a). 

Research has not quantified how methane abatement is affected by combining these strategies. We anticipate that the total methane abatement would increase with each additional strategy, but we do not expect them to be additive. The general belief is that biocovers are useful for reducing methane emissions in areas where a GCCS cannot be installed and will also help to remove residual methane emissions from GCCS systems. If there is a large increase in waste diversion, the abatement potential could be 0.13–1.59 Gt CO₂‑eq/yr for landfill methane abatement (DeFabrizio et al, 2021; Duan et al., 2022). In this scenario there will also be reduced sources of revenue due to lower LFG methane production affecting the economics.

UNEP (2021) underscored the need for additional methane measures to stay aligned with 1.5 °C scenarios. Meeting these goals requires the implementation of landfill GCCS and biocovers as well as improved waste diversion strategies – such as composting or reducing food loss and waste – to reduce methane emissions. The amount of landfill methane available to abate will grow or shrink depending on the amount of organic waste sent to landfills. Previously deposited organic waste will still produce methane for many years and will still require methane abatement.

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Table 7. Climate impact at different levels of adoption.

Unit: Gt CO₂‑eq/yr, 100-yr basis

Current adoption 0.04
Achievable – low 0.13
Achievable – high 0.97
Adoption ceiling 1.94

Unit: Gt CO₂‑eq/yr, 20-yr basis

Current adoption 0.13
Achievable – low 0.37
Achievable – high 2.82
Adoption ceiling 5.65

Unit: Gt CO₂‑eq/yr, 100-yr basis

Current adoption not determined
Achievable – low 0.98
Achievable – high 1.59
Adoption ceiling 1.94

Unit: Gt CO₂‑eq/yr, 20-yr basis

Current adoption not determined
Achievable – low 2.85
Achievable – high 4.63
Adoption ceiling 5.65
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Additional Benefits

Income and Work

Generating electricity from LFG can create local jobs in drilling, piping, design, construction, and operation of energy projects. In the United States, LFG energy projects can create 10–70 jobs per project (EPA, 2024b).

Health

Landfill emissions can contribute to health issues such as cancer, respiratory and neurological problems, low birth weight, and birth defects (Brender et al., 2011; Industrious Labs, 2024a; Siddiqua et al. 2022). By reducing harmful air pollutants, capturing landfill methane emissions minimizes the health risks associated with exposure to these toxic landfill compounds. Capturing LFG can reduce malodorous landfill emissions – pollutants such as ammonia and hydrogen sulfide – that impact human well-being (Cai et al., 2018).

Equality

Landfill management practices that reduce community exposure to air pollution have implications for environmental justice (Casey et al., 2021). A large review of waste sites in the United States and Europe found that landfills are disproportionately located near low-income communities and near neighborhoods with racially and ethnically marginalized populations (Marzutti et al., 2010). Reducing disproportionate exposures to air pollution from landfills may reduce poor health outcomes in surrounding communities (Brender et al., 2011).

Air Quality

Using LFG for energy in place of other non-renewable sources – such as coal or fuel oil – reduces emissions of air pollutants such as sulfur dioxide, nitrous oxides, and particulate matter (EPA, 2024b; Siddiqua et al., 2022). Untreated LFG is also a source of volatile organic compounds (VOCs) in low concentrations. Capturing and burning LFG to generate electricity reduces the hazards of these air pollutants. Methane emissions can contribute to landfill fires, which pose risks to the health and safety of nearby communities by releasing black carbon and carbon monoxide (Global Climate & Health Alliance [GCHA], 2024). Reducing landfill fires by capturing methane can also help improve local air quality. Landfill methane emissions can contribute to ozone pollution, particularly when other non-methane ozone precursors are present (Olaguer, 2021). 

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Risks

GCCS can be voluntarily implemented with sufficient methane generated by the landfill and favorable natural gas prices, but when natural gas prices are low, it makes less economic sense (IEA, 2021). There is also a risk of encouraging organics to be sent to landfills in order to maintain methane capture rates. Reducing the amount of waste made in the first place will allow us to better utilize our resources and for the organic waste that is created; it can be better served with waste diversion strategies such as composting or methane digesters. 

Without policy support, regulation, carbon pricing mechanism, or other economic incentives – biocover adoption may be limited by installation costs. Some tools (like the United Nations’ clean development mechanism) encourage global landfill methane abatement projects. There have been criticisms of this mechanism’s effectiveness for failing to support waste diversion practices and focusing solely on GCCS and incinerator strategies (Tangri, 2010). Collected LFG methane can be used to reduce GHG emissions for hard to abate sectors but continued reliance on methane for industries where it is easier to switch to clean alternatives could encourage new natural gas infrastructure to be built which risks becoming a stranded asset and locking infrastructure to emitting forms of energy (Auth & Kincer, 2022).

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Interactions with Other Solutions

Reinforcing

Landfill management can have a reinforcing impact on other solutions that reduce the amount of methane released to the atmosphere. By using strategies like GCCS, methane destruction, and LDAR, the landfill waste sector can help demonstrate the effectiveness and economic case for abating methane. This would build momentum for widespread adoption of methane abatement because successes in this sector can be leveraged in others as well. For example, processes and tools for identifying methane leaks are useful beyond landfills; LDAR as a key strategy for identifying methane emissions can be applied and studied more widely.

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Competing

Landfill management can have a competing impact with solutions that provide clean electricity. Capturing methane uses natural gas infrastructure and can reduce the cost of using methane and natural gas as a fuel source. As a result, it could prolong the use of fossil fuels and slow down the transition to clean electricity sources.

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Reducing the release of landfill methane will mean that solutions which divert organic waste from landfills will be less effective relative to landfill disposal.

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Dashboard

Solution Basics

Mt methane abated

t CO₂-eq (100-yr)/unit
2.79×10⁷
units/yr
Current 1.59 04.534.78
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current 0.04 0.130.97
US$ per t CO₂-eq
-6
Emergency Brake

CH₄, N₂O, BC

Solution Basics

Mt methane abated

t CO₂-eq (100-yr)/unit
2.79×10⁷
units/yr
Current Not Determined 035.1357.04
Achievable (Low to High)

Climate Impact

Gt CO₂-eq (100-yr)/yr
Current Not Determined 0.981.59
US$ per t CO₂-eq
0
Emergency Brake

CH₄, N₂O, BC

Trade-offs

Landfill management strategies outlined in this solution can help to reduce methane emissions that reach the atmosphere. However, the methane used as fuel or destroyed will still emit GHGs. Strategies to capture CO₂ emissions from methane use will be needed to avoid adding any GHG emissions to the atmosphere. Research on this topic takes global methane emissions from landfills in 2023, and assumes they were fully combusted and converted to CO₂ emissions.

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Mt CO2–eq/yr
< 0.5
0.5–1
1–3
3–5
> 5

Annual emissions from solid waste disposal sites, 2024

Landfills release methane when organic material breaks down. Globally, municipal solid waste was responsible for about 70 Mt out of the 354 Mt of anthropogenic methane emissions in 2024. This methane contributed 18% of total anthropogenic methane emissions in 2024, and is equivalent to 1,941 Mt CO2-eq based on a 100-year time scale.

Raniga, K., (2024). Waste sector: Estimating CH4 emissions from solid waste disposal sites [Data set]. WattTime, Climate TRACE Emissions Inventory. Retrieved April 21, 2025 from Link to source: https://climatetrace.org

International Energy Agency. (2025). Global methane tracker 2025: Data tools. Link to source: https://www.iea.org/data-and-statistics/data-tools/methane-tracker

Mt CO2–eq/yr
< 0.5
0.5–1
1–3
3–5
> 5

Annual emissions from solid waste disposal sites, 2024

Landfills release methane when organic material breaks down. Globally, municipal solid waste was responsible for about 70 Mt out of the 354 Mt of anthropogenic methane emissions in 2024. This methane contributed 18% of total anthropogenic methane emissions in 2024, and is equivalent to 1,941 Mt CO2-eq based on a 100-year time scale.

Raniga, K., (2024). Waste sector: Estimating CH4 emissions from solid waste disposal sites [Data set]. WattTime, Climate TRACE Emissions Inventory. Retrieved April 21, 2025 from Link to source: https://climatetrace.org

International Energy Agency. (2025). Global methane tracker 2025: Data tools. Link to source: https://www.iea.org/data-and-statistics/data-tools/methane-tracker

Maps Introduction

Methane emissions from landfills can vary geographically (IPCC, 2006) since rates of organic matter decomposition and methane generation depend on climate. In practice, however, landfill management has a more significant impact on related emissions and is correlated with country income levels.  

Many high-income countries have landfills that are considered sanitary landfills (where waste is covered daily and isolated from the environment) and have high waste collection rates. Basic covers are placed on the landfills to reduce the risk of odor, scavenging, and wildlife accessing the waste, and regulations are in place to manage and capture LFG emissions. These landfills are better prepared to install GCCS and methane use/destruction infrastructure than are other landfills. 

For landfills in low- and middle-income countries, existing waste management practices and regulations vary widely. In countries such as the Dominican Republic, Guatemala, and Nigeria, waste may not be regularly collected; when it is, it is often placed in open landfills where waste lies uncovered, as documented by Ayandele et al. (2024d). This can harm the environment by attracting scavengers and pest animals to the landfill. When this occurs, methane is more easily released to the atmosphere or burned as waste. the latter process creates pollutants that impact the nearby environment and generate additional GHG emissions.

Overall, managing methane emissions from landfills can be improved everywhere. In high-income countries, stronger regulations can ensure the methane generated from landfills is captured with GCCS and used or destroyed. In low- and middle-income countries, regular waste collection and storage of waste in sanitary landfills need to be implemented first before GCCS technology can be installed. Biocovers can be used around the world but may have the most impact in low- and middle-income countries that lack the expertise or infrastructure to effectively use GCCS methane use or destruction strategies (Ayandele et al., 2024d).

Action Word
Improve
Solution Title
Landfill Management
Classification
Highly Recommended
Lawmakers and Policymakers
  • Set standards for landfill emissions and goals for reductions.
  • Improve LDAR and emissions estimates by setting industry standards and investing in public research.
  • Mandate early installation of landfill covers and/or GCCSs for new landfills; mandate immediate installation for existing landfills.
  • Set standards for landfill covers and GCCS.
  • Invest in infrastructure to support biogas production and utilization.
  • Regulate industry practices for timely maintenance, such as wellhead turning and equipment monitoring.
  • Set standards for methane destruction, such as high-efficiency flares.
  • Conduct or fund research to fill the literature gap on policy options for landfill methane.
  • Reduce public food waste and loss, invest in infrastructure to separate organic waste before reaching the landfill (see Reduce Food Loss and Waste, Increase Composting, and Deploy Methane Digesters solutions).

Further information:

Practitioners
  • Improve LDAR at landfills for surface and fugitive emissions.
  • Install landfill biocovers as well as GCCSs.
  • Invest in infrastructure to support biogas production and utilization.
  • Ensure timely maintenance, such as wellhead turning and equipment monitoring.
  • Improve methane destruction practices, such as using high-efficiency flares.
  • Set goals to reduce landfill methane emissions from operations and help set regional, national, international, and industry reduction goals.
  • Conduct, contribute to, or fund research on technical solutions (e.g., regional abatement strategies) and policy options for landfill methane.
  • Separate food and organic waste from non-organic waste to create separate disposal streams (see Reduce Food Loss & Waste, Increase Centralized Composting, and Deploy Methane Digesters solutions).

Further information:

Business Leaders
  • Contract with waste collection facilities that utilize methane reduction strategies such as landfill covers, GCCSs, and robust monitoring systems.
  • Require suppliers to meet standards for low-carbon waste management.
  • If your company participates in the voluntary carbon market, fund high-integrity projects that reduce landfill emissions.
  • Proactively collaborate with government and regulatory actors to support policies that abate landfill methane.
  • Reduce your company’s food waste and loss (see Reduce Food Loss & Waste, Increase Centralized Composting, and Deploy Methane Digesters solutions).

Further information:

Nonprofit Leaders
  • Contract with waste collection facilities that utilize methane reduction strategies such as landfill covers, GCCSs, and robust monitoring systems.
  • Assist with monitoring and estimating landfill emissions.
  • Help design policies and regulations that support landfill methane abatement.
  • Publish research on policy options for landfill methane abatement.
  • Join or support efforts such as the Global Methane Alliance.
  • Encourage policymakers to create ambitious targets and regulations.
  • Pressure landfill companies and operators to improve their practices.
  • Reduce your organization’s food waste and loss, separate organic waste from other forms, and compost organic waste (see Reduce Food Loss & Waste, Increase Centralized Composting, and Deploy Methane Digesters solutions).

Further information:

Investors
  • Contract with waste collection facilities that utilize methane reduction strategies such as landfill covers, GCCSs, and robust monitoring systems.
  • Invest in projects that abate landfill methane emissions.
  • Pressure and influence private landfill operators within investment portfolios to implement methane abatement strategies, noting that some strategies, such as selling captured methane, can be sources of revenue and add value for investors.
  • Pressure and influence other portfolio companies to incorporate waste management and landfill methane abatement into their operations and/or net-zero targets.
  • Provide capital for nascent or regional landfill methane abatement technologies and LDAR instruments.
  • Seek impact investment opportunities, such as sustainability-linked loans in entities that set landfill methane abatement targets.
  • Reduce your company’s food waste and loss, separate organic waste from other forms, and compost organic waste (see Reduce Food Loss & Waste, Increase Centralized Composting, and Deploy Methane Digesters solutions).

Further information:

Philanthropists and International Aid Agencies
  • Contract with waste collection facilities that utilize methane reduction strategies such as landfill covers, GCCSs, and robust monitoring systems.
  • Provide capital for methane monitoring, de-risking, and abatement in the early stages of implementing landfill methane reduction technologies.
  • Support global, national, and local policies that reduce landfill methane emissions.
  • Support accelerators or multilateral initiatives like the Global Methane Hub.
  • Explore opportunities to fund landfill methane abatement strategies such as landfill covers, GCCSs, proper methane destruction, monitoring technologies, and other equipment upgrades.
  • Advance awareness of the air quality, public health, and climate benefits of landfill methane abatement.
  • Reduce your organization’s food waste and loss, separate organic waste from other forms, and compost organic waste (see Reduce Food Loss & Waste, Increase Centralized Composting, and Deploy Methane Digesters solutions).

Further information:

Thought Leaders
  • If applicable, contract with waste collection facilities that utilize methane reduction strategies such as landfill covers, GCCSs, and robust monitoring systems.
  • Provide technical assistance (e.g., monitoring and reporting landfill emissions) to businesses, government agencies, and landfill operators working to reduce methane emissions.
  • Help design policies and regulations that support landfill methane abatement.
  • Educate the public on the urgent need to abate landfill methane.
  • Join or support joint efforts such as the Global Methane Alliance.
  • Advocate to policymakers for more ambitious targets and regulations for landfill emissions.
  • Pressure landfill operators to improve their practices.
  • Reduce your food waste and loss, separate organic waste from other forms, and compost organic waste (see Reduce Food Loss & Waste, Increase Centralized Composting, and Deploy Methane Digesters solutions).

Further information:

Technologists and Researchers
  • Develop new LDAR technologies that reduce cost and required capacity.
  • Develop new biocover technologies sensitive to regional supply chains and/or availability of materials.
  • Improve methane destruction practices to reduce CO₂ emissions.
  • Research and improve estimates of landfill methane emissions.
  • Create new mechanisms to reduce public food waste and loss, and separate organic waste from landfill waste (see Reduce Food Loss & Waste, Increase Centralized Composting, and Deploy Methane Digesters solutions).

Further information:

Communities, Households, and Individuals
  • If possible, contract with waste collection facilities that utilize methane reduction strategies such as landfill covers, GCCSs, and robust monitoring systems.
  • If harmful landfill management practices impact you, document your experiences.
  • Share documentation of harmful practices and/or other key messages with policymakers, the press, and the public.
  • Advocate to policymakers for more ambitious targets and regulations for landfill emissions.
  • Support public education efforts on the urgency and need to address landfill methane.
  • Reduce your food waste and loss, separate organic waste from other forms, and compost organic waste (see Reduce Food Loss & Waste, Increase Centralized Composting, and Deploy Methane Digesters solutions).

Further information:

Sources
Evidence Base

Consensus of effectiveness in abating landfill methane emissions: High

There is a high consensus that methane abatement technologies are effective; they can often be deployed cost effectively with an immediate mitigating effect on climate change. 

Though many strategies are universally agreed-upon as effective, waste management practices vary between countries from what we found in our research. China, India, and the United States are the three largest G20 generators of municipal solid waste, though much of the data used in our assessment are from Western countries (Zhang, 2020). Ocko et al. (2021) found that economically feasible methane abatement options (including waste diversion) could reduce 80% of landfill methane emissions from 2020 levels by 2030. Methane abatement can reduce methane emissions from existing organic waste – which Stone (2023) notes can continue for more than 30 years. 

Scharff et al. (2023) found capture efficiencies of 10–90% depending on the LFG strategy used. They compared passive methods, late control of the landfill life, and early gas capture at an active landfill. The U.S. EPA (Krause et al., 2023) found that 61% of methane generated by food waste – which breaks down relatively quickly – evades gas capture systems at landfills. This illustrates how early installation of these capture systems can greatly help reduce the total amount of methane emitted from landfills. The U.S. EPA findings also highlight the potential impact of diverting organic waste from landfills, preventing LFG from being generated in the first place. 

Ayandele et al. (2024c) found that the working face of a landfill can be a large source of LFG and suggest that timely landfill covers – biocover-style or otherwise – can reduce methane released; timing of abatement strategies is important. Daily and interim landfill covers can prevent methane escape before biocovers are installed. 

Biocovers have a reported gas destruction rate of 26–96% (U.S. EPA, 2011; Lee et al., 2017). They could offer a cost-effective way to manage any LFG that is either missed by GCCS systems or emitted in the later stages of the landfill when LFG production decreases and is no longer worth capturing and selling (Martin Charlton Communications, 2020; Nisbet et al., 2020; Sperling Hansen Associates, 2020). Biocovers can also be applied soon after organic waste is deposited at a landfill as daily or interim covers where it is not as practical to install GCCS infrastructure and gas production has not yet stabilized (Waste Today, 2019). Scarapelli et al. (2024) found in the landfills they studied that emissions from working faces are poorly monitored and 79% of the observed emissions originated from landfill work faces. Covering landfill waste with any type of landfill cover (biocover or not), will reduce the work face emissions. 

LDAR can reduce landfill methane emissions by helping to locate the largest methane leaks and so allowing for more targeted abatement strategies. LDAR can also help identify leaks in landfill covers or in the GCCS infrastructure (Industrious Labs, 2024a). 

The results presented in this document summarize findings from 24 reviews and meta-analyses and 26 original studies reflecting current evidence from six countries, Canada, China, Denmark, Mexico, South Korea, and the United States, and from sources examining global landfill methane emissions. We recognize this limited geographic scope creates bias, and hope this work inspires research and data sharing on this topic in underrepresented regions.

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Appendix

The following figures provide examples of where methane can escape from landfills and where sources of emissions have been found. This shows the difficulty in identifying where methane emissions are coming from and the importance of well maintained infrastructure to ensure methane is being abated.

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Figure A1. Sources of methane emissions at landfills. Source: Garland et al. (2023).

Diagram of landfill components and emissions sources

Source: Garland E., Alves O., Frankiewicz T., & Ayandele E. (2023). Mitigating landfill methane. RMI. Link to source: https://rmi.org/wp-content/uploads/dlm_uploads/2023/06/landfill_monitoring_memo_series.pdf 

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Figure A2. Source of methane leaks at landfills. Source: Ayandele et al. (2024a).

Pie chart

Source: Ayandele, E., Frankiewicz, T., & Garland, E. (2024a). Deploying advanced monitoring technologies at US landfills. RMI. 

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