True or false: taking the commuter train across Boston results in lower greenhouse gas emissions than travelling the same distance in a jumbo jet. Perhaps surprisingly, the answer is false.
A new study compares the "full life-cycle" emissions generated by 11 different modes of transportation in the US. Unlike previous studies on transport emissions, this one looks beyond what is emitted by different types of car, train, bus or plane while their engines are running and includes emissions from building and maintaining the vehicles and their infrastructure, as well as generating the fuel to run them.
Including these additional sources of pollution more than doubles the greenhouse gas emissions of train travel. The emissions generated by car travel increase by nearly one third when manufacturing and infrastructure are taken into account. In comparison to cars on roads and trains on tracks, air travel requires little infrastructure. As a result, full life-cycle emissions are between 10 and 20 per cent higher than "tailpipe" emissions.
Mikhail Chester and Arpad Horvath of the University of California, Berkeley, included in their calculations data on the "life expectancy" of each component of each mode of transportation, such as the tracks used by a train and the airports used by aircraft.
They calculated the total "travel kilometres" each component allows and how many tonnes of greenhouse gases were emitted to build and maintain each component. This allowed them to calculate the component's emissions per kilometre travelled, for each mode of transport per kilometre for each traveller on board.
oh my...
2 comments:
Dammit dammit dammit!
There is a question of scale. Most train rides are shorter commuter rail rides. The typical ride “taking the commuter train across Boston” involves curving tracks, waiting for track lights to change etc and other inefficiencies. However, if you were to load a jet to fly a person across the city - the advantage to the plane efficiency would disappear.
I suppose I would have to see the study and see the inputs to determine how accurate the study is.
The airplane is most efficient at getting people long distances fast. Trains have their best efficiencies carrying heavy loads that can not be flown efficiently long distances. People are high demand cargo. To take a train across the country means that a person needs to be served and provided for for several days on the train ride. A plane ride can get someone across the country much quicker - maybe just providing them with one meal.
tom donlon
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