The UN’s latest climate action report says that shifting more trips to public transit is “essential” to curbing climate change. Estimates suggest that global public transport capacity must double by 2030 — in a little more than four years — if the world is to limit global warming to 1.5 degrees C (2.7 degrees F) and avert the worst impacts of climate change.
THE VALUE OF PUBLIC TRANSPORTATION
Public transportation gets people where they’re going while emitting far fewer climate-warming greenhouse gases than private cars. The reason is simple efficiency: while cars usually carry just one or two people at a time, a bus can carry 50 or more, and a train in a large city may carry thousands. Currently, the U.S. public transportation saves about 37 million metric tons of carbon dioxide annually and that is with only about 9% of Americans commute to work by public transportation, walking or cycling. Public transport is only one strategy. Sustainable transport is a systems approach that integrates technology, infrastructure, planning, policy and behavior change to minimize greenhouse gas emissions while simultaneously considering factors like safety, affordability, energy, resource efficiency, and equitable access to mobility. Investing in public transit and denser land-use in communities has mutual benefits for supporting other zero-emission mobility options like biking and walking.
WHAT POWERS OUR PUBLIC TRANSPORT?
While metro rail and light rail transit are largely powered by electricity in the US, our trucks and buses are still overwhelmingly reliant on fossil fuels (around 96% in total), primarily diesel (81%) and gasoline (11%). These not only cause significant emissions, but also contribute to air pollution and related health risks in cities. Impacts are often the worst in low-income and disadvantaged communities, which are disproportionately located near transport infrastructure.
CAN WE DO BETTER?
Electric buses are a much cleaner option, emitting less than half as much carbon as gas-powered private cars per passenger-kilometer traveled. In 2021, the Institute for Transportation & Development Policy released a comprehensive report on the status of electric buses in major global cities including key steps needed for bus fleet electrification such as bus route planning, investment models, charging infrastructure, and city government policy.
DID WE MAKE ANY PROGRESS UNDER THE BIDEN ADMINISTRATION?
In 2024, the Biden administration continued its crackdown on carbon pollution by finalizing tough new limits on tailpipe emissions from heavy-duty trucks and buses. The new rules, which the EPA projected would keep a billion tons of carbon dioxide from entering the atmosphere, could encourage more trucks and buses to use electric motors or experiment with alternative fuels. Those new rules would apply to a plethora of big vehicles, some public, some not— delivery vans, trash trucks, city and school buses, even 18-wheelers — and go into effect starting in model year 2027.
WHERE ARE WE IN 2025 UNDER TRUMP?
- In July, 2025, however, the Trump administration’s EPA, proposed to repeal the endangerment finding, which allows the EPA to regulate GHG emissions, it is unclear if these limits will still go into effect.
- During the government shutdown in October 2025, the Trump administration revoked federal funding for mass transit projects in various states, including cancelling grants for bike lanes and pedestrian thoroughfares, and threatening to withhold billions from New York and Chicago’s metro systems.
- In March, 2025, Trump’s Secretary of Transportation Sean Duffy had directed staff to review and freeze projects focused on climate and equity, and sent letters to the MTA and the WMTA threatening to withhold funding if crime and fare evasion was not dealt with, despite stats showing crime has been trending downwards since the pandemic.
- In November 2025, the DOT announced $2 billion for 165 transit projects in 45 states from the Grants for Buses and Bus Facilities Program and the Low or No Emission Grant Program to replace diesel buses with natural gas CNG buses.
A LITTLE GOOD NEWS
NYC’s has instituted a first of its kind congestion pricing program, which incentivizes and raises revenue for public transit while reducing traffic. A huge success, traffic is down throughout the NYC region; quality of life has improved and transit ridership has surged. Trump tried to shut it down in February but a court blocked his order in May.
Recovering 
