In terms of running costs, EVs are definitely the most economical cars, though they cost a bit more to buy outright. However, vehicles that utilize regular gasoline, diesel, or alternative fuels can still be fuel efficient, too. Of the various types of fuels mentioned here, fuel cell vehicles like the Honda Clarity, Hyundai Nexo, and the Toyota Mirai offer superb EPA estimates, with mileage figures for each working out to 68, 61, and 74 MPGe in combined cycles, respectively.