By 2025, national fuel economy standards will hit an equivalent of 54.5 mpg, but many of these 2014 high-mileage cars are already there.
This list of the 12 greenest cars of 2014 is based on scoring by GreenerCars.org. Green Score, car specifications and mpg ratings are from GreenerCars.org. Miles per gallon equivalent is from FuelEconomy.gov; prices on these high-mileage cars are from the manufacturer.
The Greenercars.org Green Score is based on a zero to 100 scale. A higher score indicates a greener vehicle.