Tertiary Source

Rail fuel economy

2008-12-05 01:04:24

Dylan Foley pointed out to me that my question about CSX's advertised fuel efficiency has previously gotten attention from FactCheck.org.

The advertised figure of 400-ish ton-miles per gallon of diesel apparently comes in a straightforward way from a rail-industry-wide report assembled by the federal government. Some random forum person estimates that a forty-ton tractor-trailer gets four miles per diesel gallon, about half the fuel efficiency of a train.

Neither of these figures includes the cost of adding or maintaining infrastructure. From a freight-only perspective, which costs less to build and maintain, rails or highways? The mixed uses of highways add a lot of value, too. I'd like to do this estimate more carefully. This sort of omission always reminds me of a comment I heard from David Goodstein while he was promoting his book Out of Gas: that no photovoltaic cell, if you account for the energy required to produce doped perfect silicon crystals, has ever extracted more solar energy than was required for its construction.

Interesting that the rail-versus-truck "debate" summarized at FactCheck focuses on short-term differences in fuel efficiency, like a regulation prohibiting trucks from burning sulfured diesel which will not apply to trains until 2012. Does that suggest that (these) industry folks don't expect the present public interest in environmentalism to last long enough to impact infrastructure-scale planning?

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