Trains aren’t necessarily good for the climate
June 8th, 2009A new study comparing “full life-cycle” emissions finds trains aren’t necessarily good for the climate.
The study, Environmental assessment of passenger transportation should include infrastructure and supply chains by Mikhail Chester and Arpad Horvath of U.C. Berkeley examined total car, train, bus and plane emissions – including not only emissions from running the vehicles, but also emissions from building and maintaining the vehicles and their infrastructure and from generating the fuel to run them. The study found that total life-cycle energy inputs and greenhouse gas emissions contribute an additional 63% for on-road vehicles, 155% for rail, and 31% for air systems over vehicle tailpipe operation.
Ranges in passenger occupancy radically affect the relative performance of modes. Empty seats really hurt the performance of mass transit options such as busses and trains. And electric trains and electric cars aren’t “green” if the electricity is generated by burning coal.
More than half of the life-cycle emissions from rail comes not from the engines’ exhausts, but infrastructure development, such as station building and track laying, and providing power to stations, lit parking lots and escalators. Crisscrossing the US with a rail network would thus result in an up-front surge in emissions. Any effort to expand the rail network should take into account the emissions it will generate in doing so.
Chester says rail systems need to be carefully integrated with other modes if they are to be effective in reducing emissions:
New rail systems should serve as links to other transit modes, as is often the case in Europe and Japan. We should avoid building rail systems that are disconnected from major population areas and require car trips and parking to access.