Friday, June 30, 2006

CO2: Train v. Car

A couple of weeks ago I was on a crowded Tokyo train, and there was an ad at the far end of the car with some interesting data. It showed a family of four travelling by car, and producing 880 liters of CO2 emissions. In contrast, travelling by train produced 92 liters.

I couldn't get close enough to the ad to read the details, and haven't seen it again. First question is what kind of assumptions they are making -- is this packed-to-the-gills subway versus stuck-in-traffic Hummer, or is it uncrowded shinkansen green car (first class) versus K car (sub-sub-compact)? My guess would be the that comparison is intended to be favorable to the train.

I'd also like to know how many kilometers, whether luggage is involved, etc. And how is the electricity to drive the train assumed to be produced? What losses are included? Does the gasoline figure include exploring, pumping, refining, transporting, and delivering the petroleum?

This comparison is worth what you're paying for it, but it's a start...anybody got pointers to a detailed analysis, ideally including shinkansen v. airplane?


At 6:58 PM, Blogger Leucipo said...

And in principle (but nobody has implemented it) a train could work today with high temperature fuel cells such as this one
while a fuel cell car (or even a bus) relies in the very experimental and fragile technology of PEM membrane fuel cells.

The disadventages of HT FC, excess heat and warm-up time, are not a problem for railways: heat can be used in passenger cars, and the preheating can be scheduled.


Post a Comment

<< Home