2012 Mitsubishi i

The Mitsubishi i electric car is now the most fuel-efficient car sold in the United States, according to the EPA and the Department of Energy. Until the release of the 2012 Fuel Economy Guide, the Nissan Leaf had the country’s highest combined fuel economy rating, but with the 2012 Mitsubishi i now on the market, the Leaf has slipped to second place.

The EPA rates the electric Mitsubishi i at 126 miles per gallon-equivalent (mpg-e) in the city, and 99 mpg-e on the highway, for a combined rating of 112 mpg-e. Also at the top of the list are the Nissan Leaf, with a combined rating of 99 mpg-e, the Ford Transit Connect Electric, with 62 mpg-e and the Chevrolet Volt, at 60 mpg-e.

No gas-only models made the list of top 10 fuel sippers, but the rest of the list is made up of hybrid models. “The highest-rated vehicle powered by a conventional internal combustion engine continues to be the Toyota Prius, at 50 miles per gallon combined,” notes Autoblog.

The 2012 Fuel Economy Guide also rates the cars on the market with the worst fuel economy. The 12-cylinder Aston Martin DBS and DB9 both get just 13 mpg combined, but Mercedes-Benz makes up almost a third of the list on its own. The CL600, CL65 AMG, S600 and S65 AMG all get 14 mpg combined, while the E63 AMG wagon gets a marginally-better 18 mpg combined.

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