The chances are, if you’re driving a Mercedes-Benz, you’re harming the environment.

Out of 12 cars on greenercars.org’s annual greenest and meanest car list, five of them in the “meanest” categories were Mercedes-Benz’s.

That said, the number one greenest car this year is a Mercedes-Benz Smart ForTwo Electric Drive Convertible/Coupe.

The greenest: Mercedes-Benz Smart ForTwo Electric Drive Convertible/Coupe Photo courtesy of Mercedes-Benz

The American Council for an Energy-Efficient Economy (ACEEE) maintains the greenercars.org website and produces the annual rating.

The ACEEE analyzes auto manufacturer’s test results for fuel economy and emissions as reported to the U.S. Environmental Protection Agency and the California Air Resources Board.

The analysis includes pollution estimates from vehicle manufacturing and an air pollution count such as fine particles, nitrogen oxides, hydrocarbons and other pollutants, according to the health problem each pollutant causes.

The ACEEE then factors in greenhouse gases and combines the emissions estimates into a green score than runs on a scale for zero to 100. The top vehicle this year scores a 63, while the average is 40. The worst gas-guzzlers score around 20.

With a rating of 20, the worst car on the list is the Mercedes-Benz G65 AMG 20. The number two spot goes to the Chevrolet/GMC G2500 Express/Savana (Passenger) (MDPV) with a rating of 22.

Rounding out the top three meanest is the Mercedes-Benz G63-AMG with a rating of 22.

The runner-up greenest car: Chevrolet Spark EV Photo courtesy of Chevrolet

For the first time ever in the 19 years of the list, the greenest category is completely populated by plug-in and hybrid vehicles; not a single car with only an internal combustion engine appears.

“The 2016 scores are in, and plug-in electric vehicles are outpacing all other vehicle offerings in terms of environmental friendliness,” said ACEEE lead vehicle analyst Shruti Vaidyanathan.

“Nevertheless, it’s important to acknowledge that how green your electric vehicle truly is depends on the electricity it uses to charge,” Vaidyanathan added.

Besides the aforementioned Mercedes-Benz Smart ForTwo with a score of 63 in the first spot, the runner-up was the Chevrolet Spark EV with a rating of 63 followed by the Fiat 500# with a rating of 62.

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