Operating a vehicle on electricity in the United States is considerably less expensive than operating a vehicle on gasoline. In large part, this is due to the high efficiency of electric motors, which can turn more than 90 percent of the energy content of electricity into mechanical energy. In contrast, today's best internal combustion engines have efficiency ratings of just 25 to 27 percent.

With gasoline at $3.00 per gallon, the operating cost of a highly-efficient IC engine vehicle (30 miles per gallon) is 10 cents per mile. For current pure electric vehicles, assuming an average electricity price of 10 cents per kilowatt hour, operating costs are only 2.5 cents per mile.  Recent research confirms the potential savings of electric propulsion. The Electric Power Research Institute has determined that a compact size plugin electric hybrid vehicle will use only 160 gallons of gasoline a year, compared to 300 in a traditional gasoline electric hybrid and 400 in a conventional internal combustion engine compact car. With gasoline at $3 a gallon, a plug-in hybrid would save its owner $10,000 over the course of the vehicle's lifetime compared to a conventional vehicle.