A study conducted by the nonpartisan National Bureau of Economic Research shows that electric cars are hurting the environment more than gas-powered vehicles.

On average, electric vehicles are half a cent worse for the environment than their gas counterparts, according to Buzzpo. The study showed that the environmental effects varied with the surroundings. In the city, electric vehicles performed 3.3 cents better per mile compared to gas. However, in Grand Forks, N.D., gas-powered cars were 3 cents better than electric vehicles, The Daily Caller reports. Although the purchase of an electric vehicle lowers air pollution in 38 states, according to Washington Examiner, the power has to come from somewhere, and that is usually from power plants that run on coal.

"Rather than simply accepting the assertion of environmental benefits from electric vehicle use, this paper conducts a rigorous comparison of the environmental consequences of gasoline and electric powered vehicles, specifically by quantifying the externalities (both greenhouse gases and local air pollution) generated by driving these vehicles," the authors of the study concluded.

The authors also think that the government should tax vehicles on a per-mile basis. They believe that this will be more efficient in the effort to curb carbon emissions.

The study was conducted by four business and economics professors: Erin Mansur of Dartmouth College, Nicholas Muller of Middlebury College, Stephen Holland of the UNC Greensboro and Andrew Yates of UNC at Chapel Hill, according to the Washington Examiner.

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