The list, posted at GreenerCars.org, saw a considerable shake-up, as the battery electric vehicle claimed the top spot from the Honda Civic Natural Gas, which has held on to first place for eight years in a row.
In its model year 2012 debut on the American market, the i-MIEV earned a score of 58, the highest Green Score awarded since ACEEE began ranking vehicles in 1998. Its combined city and highway fuel economy of 112 miles per gallon equivalent outpaces all other vehicles currently sold in United States. “Even taking into account the emissions generated from the electricity used to power the i-MIEV, it still handily outscores other vehicles on the market today,” said ACEEE lead vehicle analyst Shruti Vaidyanathan.
Despite its improved fuel economy this year, the Honda Civic Natural Gas slipped to second place, tying with the Nissan Leaf. The Toyota Prius, Honda Insight and Smart ForTwo rounded out the top six performers.
This year, hybrids dominate the “Greenest” list, occupying half of all spots. Highly efficient conventional gasoline vehicles also continue to have a presence on the “Greenest” list, claiming three of the top twelve spots. This year saw the arrival of a number of new hybrid options for drivers from Hyundai, Kia and Infiniti, but none broke into the top twelve.
Vaidyanathan noted that earning a spot on the “Greenest” list is getting tougher as automakers employ a greater variety of vehicle technologies. “It’s increasingly obvious that automakers are fully invested in providing consumers with the widest possible array of vehicle choices,” he said.
GreenCars.org ranks vehicles with a “Green Score” that incorporates unhealthy tailpipe emissions, fuel consumption and emissions of gases that contribute to climate change. ACEEE made a number of updates to the Green Book® methodology this year to more accurately reflect vehicles’ environmental impacts. Improved emissions estimates for the vehicle manufacturing process, changes reflecting current natural gas extraction practices and consideration of upcoming shifts in the generation mix for the electricity used to power electric cars are now factored into the vehicle’s score.