Large suspension bridge highway leading into a city, with a cargo ship passing below.
Sector Summary

Transportation

58–97.4
Gigatons
CO2 Equivalent
Reduced / Sequestered
(2020–2050)

Getting people or things from point A to point B, and perhaps back again: in some ways, transportation is incredibly simple. Human beings would be stuck at the speed of walk, run, swim, or horse if it weren’t for planes, trains, automobiles, buses, bicycles, and boats. Mobility has played a critical and complex role in shaping society, and the demand for it is only growing.

Most of the energy driving mobility has, to date, been generated by burning liquid hydrocarbons, namely gasoline, diesel, and jet fuel. Why? Because of a formidable combination of energy density (the energy contained within a liter or gallon), abundance, and low cost. But account for what isn’t included in that price, and petroleum-powered mobility is expensive indeed. Particulate matter harms human health. Oil spills ruin land and water. And then there’s the cost to the climate system: Transportation is responsible for 14% of global greenhouse gas emissions.

How can we support the social good of mobility, but end its dependence on petroleum? In what ways do vehicles, infrastructure, and operations need to change, to eliminate transportation emissions? These are the questions society must answer if we want to keep moving—ourselves or other items—for reasons of necessity, pleasure, or commerce. Transportation solutions address alternatives, fuel efficiency, and electrification. 

  • Shift to Alternatives. Alternative modes of mobility reduce demand for fossil-fueled transportation or replace it altogether. With public and “pooled” transit, we can make the most of available seats. Compact cities, intentional infrastructure, and advanced communication technologies make it possible to walk, cycle, or simply stay put.
  • Enhance Efficiency. Where combustion engines remain in use, vehicles can be made far more fuel-efficient through mechanical improvements, lightweighting, better design, and more artful operation. 
  • Electrify Vehicles. Electrification of vehicles completely replaces petroleum—and has even greater benefits when paired with renewable electricity generation. (If charged from coal-powered electricity, EVs can cause more harm than good.)

These transportation solutions have the potential to save money and preempt pollution, but the transformations required are substantial and the sector can be slow to move. Vehicles remain in use for many years. New transportation infrastructure is expensive and takes time to build. Clean fuels for airplanes remain distant. But many of the solutions can, if done intelligently, create more equitable mobility and livability in our cities and communities, without forfeiting the stability of our climate.