Why Some Electric Vehicles Are No More Green Than Gasoline-Powered Ones

As Americans increasingly turn to electric vehicles due to rising gas costs and interest in reducing greenhouse gas emissions, a new report shows that another set of calculations should be considered. The report, released by the Union of Concerned Scientists on Monday, shows that "the effect of electric vehicles on the amount of greenhouse gases released into the environment can span a wide range, varying with the source of the electricity that charges them. "

Their well-to-wheels analysis considers the full cycle of energy production. "It demonstrates that in areas where the electric utility relies on natural gas, nuclear, hydroelectric or renewable sources to power its generators, the potential for electric cars and plug-in hybrids to reduce carbon dioxide emissions is great. But where generators are powered by burning a high percentage of coal, electric cars may not be even as good as the latest gasoline models - and far short of the thriftiest hybrids."

Stenquist examines the geographical breakdown of electricity generation. Electricity in the midsection of the U.S. is generated in large part by coal, while cities like Seattle and Los Angeles, and surprisingly, Buffalo and New Orleans, are in regions where there is cleaner power.

According to data released in 2010 by the United States Energy Information Administration, "45 percent of the country's electricity is generated by burning coal, the dirtiest fuel. Natural gas, a much cleaner fuel, accounts for 24 percent of electricity production, a figure that is shifting rapidly with price swings. Nuclear plants generate 20 percent of the nation's power, while wind, solar and geothermal sources provide 3 percent." While these numbers help to educate, they also affirm the need for changes in electric power generation in order to maximize the use of electric and hybrid cars.