For a list of the greenest 2011 model-year vehicles, there sure are a lot of traditional gasoline engines among the top 12 cars ranked by the American Council for an Energy-Efficient Economy.

The council's 14th annual ratings of the most eco-friendly cars on the market include internal combustion models such as the Smart Fortwo, the Ford Fiesta and the Hyundai Elantra.

Greenest cars: natural gas Honda Civic GX, Nissan Leaf electric and, just barely, Chevrolet Volt | Greenspace | Los Angeles Times