Mercedes-Benz’s Smart ForTwo Electric Drive convertible coupe is the greenest vehicle of 2014 while the Ram 2500 truck is the “meanest,” or least environmentally friendly, according to the American Council for an Energy-Efficient Economy’s (ACEEE) annual vehicle environmental ratings.
The Smart ForTwo Electric Drive earns a highest-ever score of 59 out of 100, just in time for the vehicle’s nationwide rollout. The second- and third-ranked cars are the Toyota Prius C and the Nissan Leaf with scores of 57 and 55, respectively. The other greenest cars include the Toyota Prius (no. 4), Honda Civic Hybrid (no. 5), Lexus CT 200H (no. 6), Toyota Prius plug-in hybrid (no. 7), Mitsubishi Mirage (no. 8), Honda Civic natural gas vehicle (no. 9) and Honda Insight (no. 10).
The meanest list this year is comprised of heavier light-duty vehicles and European sports cars. The dirtiest vehicle for 2014 — the Class 2B Ram 2500 — with a green score of 18 is followed by the Bugatti Veyron and the Ford E-150 FFV Wagon with scores of 19 and 21, respectively.
The 2014 vehicle ratings on Greenercars.org assign each vehicle a “green score,” a number that incorporates lifecycle greenhouse gas and criteria pollutant emissions. This year, a number of updates were made to the methodology to more accurately estimate vehicles’ environmental impacts, ACEEE says. These include updates to in-use emissions of methane and nitrous oxides, evaporative emissions estimates, and gasoline, diesel, and natural gas “upstream” emissions. Vehicles not intended to achieve significant sales volumes are not eligible for spots on the greenest list.
The average fuel economy of all vehicles sold in 2013 was a record 24.8 mpg, up 1.0 mpg from 2012 and up 3.9 mpg from 2008, according to the University of Michigan Transportation Research Institute.