Refrigerant Management

Fluorinated gases, which are widely used as refrigerants, have a potent greenhouse effect. Managing leaks and disposal of these chemicals can avoid emissions in buildings and landfills.

Reduce SourcesIndustryAddress Refrigerants
Reduce SourcesBuildingsAddress Refrigerants
57.15
Gigatons
CO2 Equivalent
Reduced/Sequestered
2020–2050
-622.73
Billion US$
Lifetime Net
Operational Savings
Research Fellows: Zak Accuardi, Susan Miller Davis, Barbara Rodriguez Droguett, Marzieh Jafary, Kapilnarula, Karthik Mukkavilli, Jon Schroeder; Senior Fellow: Kevin Bauyk; Senior Director: Chad Frischmann

Impact

Practices to avoid leaks from refrigerants and destroy refrigerants at end of life can substantially reduce emissions, both before and after the adoption of alternatives to hydrofluorocarbon refrigerants. Over 30 years, preventing 100 percent of refrigerant leaks that otherwise would be released can avoid emissions equivalent to 57.15 gigatons of carbon dioxide. Although some revenue can be generated from resale of recovered refrigerant gases, the costs to establish and operate recovery, destruction, and leak avoidance systems outweigh the financial benefit—meaning that refrigerant management, as modeled, would incur a net lifetime cost of US$622.73 billion.

Introduction

Refrigerants are used as working fluid in commercial refrigeration systems; in household appliances such as air conditioners and refrigerators; in refrigerated containers used for carrying perishable goods; in air conditioning systems onboard cars, trains, aircraft, and ships; in industrial cooling systems; and more. There are various classes of refrigerants, including chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs), and natural refrigerants such as CO2 and NH3. All have a high global warming potential (HFCs, for example, have 1,000 to 9,000 times greater capacity to warm the atmosphere than carbon dioxide) and their release into the environment during production, from existing appliances and equipment due to leakages, and during end-of-life disposal of appliances contributes to climate change.

CFCs are ozone-depleting substances and have been phased out under the Montreal Protocol, and HCFCs are currently being phased out. HFCs, which do not deplete the ozone layer, emerged as an alternative to HCFCs and have grown to extensive use. Due to their large impact on global warming, world leaders agreed in 2016 to replace HFCs with natural refrigerants with much less warming potential. Still, the bank of HFCs will grow substantially before all countries halt their use. Because 90 percent of refrigerant emissions happen at end of life, effective disposal of those currently in circulation is essential. After being carefully removed and stored, refrigerants can be purified for reuse or transformed into chemicals that do not cause warming.

Refrigerant management can be undertaken in five main ways:

  1. Lower the demand/use of appliances.
  2. Replace refrigerants with low-warming HFCs/new cooling agents/non-HFC substances.
  3. increase the refrigeration efficiency in appliances.
  4. Control leakages of refrigerants from existing appliances.
  5. Ensure recovery, reclaiming/recycling, and destruction of refrigerants at end of life.

Project Drawdown’s Refrigerant Management solution controls leakages of refrigerants from existing appliances through application of the last two options. This solution replaces conventional refrigerant management practices.

Methodology

To model the Refrigerant Management solution, we forecasted a total addressable market of refrigerant gas emissions for 2020–2050 in kilotonnes of carbon dioxide equivalent emissions per year, forecasted adoption of management measures and the resulting decreased emissions from those measures for each year from 2020 to 2050, and then compared the difference in emissions from the total market and the adoption scenarios.

Total Addressable Market

The model uses available projections for the size of refrigerant banks after considering the adoption of Project Drawdown’s Alternative Refrigerants solution, which reduces the size of HFC banks. It then estimates the leakages from these banks using historical leakage rates for various subsectors such as commercial, industrial, domestic, and stationary air conditioning systems to create the total addressable market.

We modeled adoption of good practices to control leakages as a part of the solution as well as the costs of applying these measures. We also estimated the current quantity of refrigerants that are recovered and destroyed at the end of their lives using historical data on equipment retirement rates, recovery efficiency, and destruction efficiency. For 2014, we estimated current adoption to be around 30 kilotonnes of refrigerant, which is approximately 3.4 percent of the total quantity emitted.

This solution models the potential of capturing a higher portion of this refrigerant stream. Estimates of refrigerant banks in the future are used to calculate the end-of-life banks based on the expected lifetime of the equipment. Thereafter, higher recovery efficiencies are assumed based on the technical feasibility of recovery from various subsectors. Assumptions regarding increased destruction efficiencies are then used to estimate the refrigerant that can be destroyed in the future along with cost implications. The two parts of the solution are then combined to calculate the total impact.

Adoption Scenarios

We calculated impacts of increased adoption of refrigerant management from 2020 to 2050 by comparing two scenarios with a reference scenario in which the market share was fixed at current levels.

  • Scenario 1: 719.39 kilotonnes of recoverable refrigerant are destroyed (100 percent of the total addressable market).
  • Scenario 2: 719.39 kilotonnes of recoverable refrigerant are destroyed (100 percent of the total addressable market).

Emissions Model

In the conventional case, direct emissions from refrigerants that leak during the lifetime and at the end of an appliance’s life contribute to global warming. These depend on the quantity of refrigerants emitted into the environment and their respective global warming potential. For the Refrigerant Management solution, we use a weighted average global warming potential of 2,326 based on numerous refrigerant variants in the market.

Refrigerant destruction facilities use modest amounts of electricity. We quantify this as energy in kilowatt-hours per kilogram of refrigerant being destroyed.

Financial Model

We consider only the operating costs for this solution. Control of leakage from appliances has no up-front costs (Purohit and Isaksson, 2017) but does have operational and maintenance. We only included collection, recovery, and destruction in operational costs. The annual costs multiplied by the estimated emissions avoided give the total costs and the average annual costs per unit of HFC avoided for different years.

We calculated the total costs for end of life recovery, removal, and destruction in a similar way.

Results

Scenario 1 saved 57.15 gigatons in carbon dioxide equivalent emissions with a net operating cost of US$622.73 billion. Scenario 2, which optimized recovery factors and destruction rates, showed an identical reduction and cost.

Discussion

It’s hard to manage refrigerants because appliances are distributed. Weak regulations control leakage of refrigerants, end-of-life recovery, and refrigerant production. Further, there are no economic incentives for the recovery of refrigerants. Funding, training, technical, and informational barriers also limit adoption of this solution.

To increase adoption, policies and regulations on recycling and management of refrigerants need to be formulated and implemented. Strong regulations such as a complete ban on venting of refrigerants and accountability of refrigerants must be introduced in national legislation. Economic incentives for recovery, recycling, and destruction of refrigerants, such as the issuing of carbon credits under the Kyoto Protocol, would help increase the adoption in low-income countries. Capacity-building in these countries, including technology transfer, would help speed adoption of the solution.

References

Purohit, P. and Höglund-Isaksson, L (2017). Global emissions of fluorinated greenhouse gases 2005–2050 with abatement potentials and costs. Atmospheric Chemistry and Physics, 17(4) pp 2795-2816. DOI: 10.5194/acp-17-2795-2017