Charging Ahead: Creating electricity for hybrids has less effect on the environment than using gasoline

Credit: Photo Courtesy of Tesla Motors

Powering an all-electric car, such as this Tesla Roadster, costs less than using gasoline.

By: JournalNow Staff | E/THE ENVIRONMENTAL MAGAZINE
Published: April 21, 2009

Dear EarthTalk: If you have an electric or plug-in hybrid car, you are paying for electricity rather than gasoline all or most of the time. How does that cost compare with a gas-powered car's cost per mile? And since the electricity may be generated from some other polluting source, does it really work out to be better for the environment? -- Kevin DeMarco, Milford, Conn.

Dear Kevin: When you compare battery to gasoline power, electricity wins hands down.

A 2007 study by the nonprofit Electric Power Research Institute calculated that powering a plug-in hybrid electric vehicle, or PHEV, would cost the equivalent of roughly 75 cents for every gallon of gasoline -- a price not seen at the pump for 30 years.

The calculation was made using an average cost of electricity of 8.5 cents for a kilowatt hour and the estimated distance the car would travel on one charge, versus a car that gets 25 miles a gallon and is powered by $3-a-gallon gasoline. Change any of those variables and the relative costs change. For example, substituting a car that gets 50 miles a gallon doubles the comparative electrical cost (though it still works out much cheaper than gasoline). On the other hand, in some areas where wind or hydropower is wasted at night -- just when the PHEV would be charging -- the utility might drop the kilowatt hour cost to 2 or 3 cents, making the charge much less costly.

And don't worry that we will run out of electrical power: A 2005 study by the U.S. Department of Energy's Pacific Northwest National Laboratory estimated that three-quarters of the country's current small-vehicle fleet could be charged by our existing electrical grid without building new power plants. (And if all those cars were replaced by PHEVs, it would eliminate the need for 6.5 billion barrels of oil a day, or 52 percent of current U.S. oil imports.)

Regarding environmental impact, charging up your car with electricity from the grid also wins handily over filling up at the gas station. In the most comprehensive PHEV study to date, released in 2007 by the power-research institute and the nonprofit Natural Resources Defense Council, results predict that all greenhouse gases will be reduced as PHEVs begin to penetrate the car market. Estimated cumulative greenhouse-gas reductions from 2010 to 2050, depending upon how fast PHEVs take hold, range from 3.4 tons to 10.3 billion tons.

More than one-half of our national energy grid is powered by coal, and in areas where PHEVs are charged through coal-provided electricity, the resources defense council says, there is the possibility of increased levels of soot and mercury emissions. But charging up is cleaner where such electrical sources as wind and solar are available. The Web site HybridCars.com points out that as more power plants are required to develop green power and emit fewer greenhouse gases, the environmental and health benefits will further increase.

■ Do you have an environmental question? Send it to: EarthTalk, c/o E/The Environmental Magazine, P.O. Box 5098, Westport, CT 06881; submit it at www.emagazine.com/earthtalk/thisweek; or e-mail: earthtalk@emagazine.com. Read past columns at: www.emagazine.com/earthtalk/archives.php.