EVs are the most efficient cars on the road. See the federal government's report on energy use:

Toyota RAV4 EV: 887 BTU/mile (rated 112 miles per gallon equivalent)

Toyota Prius: 2250 BTU/mile

Toyota RAV4 Gas: 4423 BTU/mile

http://fueleconomy.gov/feg/byfuel/byfueltypeNF.shtml