Crunching the numbers on alternative fuels.

In the lab, many gasoline alternatives look good. Out on the road, automotive engineers have a lot of work to do, and energy companies have new infrastructure to build, before very many people can drive off into a petroleum-free future. And, there’s the issue of money. Too often, discussions of alternative energy take place in an alternative universe where prices do not matter.

For this special report, PM crunched the numbers on the actual costs and performance of each major alternative fuel. Before we can debate national energy policy–or even decide which petroleum substitutes might make sense for our personal vehicles–we need to know how these things stack up in the real world.

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