Hey Mr. Green, Don't Electric Cars Guzzle Coal Power?

Hey Mr. Green,

You've pointed out that electric vehicles (and plug-in hybrids) are only as clean as the fuel that generates their electricity. But since power sources vary from region to region, how do you check your utility's power sources and emissions levels before deciding on an EV or a plug-in?

--Stan in Carson City, Nevada

This is a smart, important question (typical of Sierra's astute, informed audience). Coal, a dirty fuel often gouged out and processed in ways that play hell with nature, generates 42 percent of U.S. electricity, according to the U.S. Energy Information Agency. And you're right about big regional variations. My local utility in California, for example, relies on coal for just 7.6% of its electricity generation. To find out how much coal your utility burns, check the EPA's Power Profiler.

Even utilities that use a lot of fossil fuels or nuclear energy might offer juice from renewable sources, though, so ask your provider about its clean-energy options. If EV fans' zeal for clean power ever starts to match their religious devotion to their cars, they might quickly push utilities and politicians toward saner energy sources. 

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This article has been corrected.