Cost of EV vs Gas engines

Electric Cars--How Much Does It Cost per Charge?

When you compare battery to gasoline power, electricity wins hands down. A 2007 study by the non-profit Electric Power Research Institute (EPRI) calculated that powering a plug-in hybrid electric vehicle (PHEV) would cost the equivalent of roughly 75 cents per 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 per kilowatt hour and the estimated distance the car would travel on one charge, versus a car that gets 25 miles per gallon and is powered by $3 per gallon gasoline. Change any of those variables and the relative costs change. For example, substituting a car that gets 50 miles per 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 two to three cents, making the charge much less costly.

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