New cars and trucks in the U.S. got a record 24.1 miles per gallon on average last year, but the rate of improvement is slowing as buyers shift back toward trucks and SUVs.
The Environmental Protection Agency says fuel economy rose one-half mile per gallon over 2012, mainly because automakers have improved gas engines and transmissions and added turbochargers to give smaller motors more power.
"We are thrilled to see that manufacturers continue to innovate and are bringing technologies to improve fuel economy online even faster than anticipated,” EPA Administrator Gina McCarthy said in a statement. “Consumers now have many more choices when shopping for vehicles with higher fuel economy and lower emissions compared to just five years ago. These choices reflect both a more diverse range of technology packages on conventional gasoline vehicles as well as more advanced technology and alternative-fueled vehicles.”
But last year's gain fell short of the 1.2 mpg improvement from 2011 to 2012. And the EPA is predicting smaller growth for 2014. Still, fuel economy is up almost 5 mpg since 2004.
Mazda led all automakers with an average of 28.1 mpg. Chrysler, General Motors and Ford were at the bottom of the rankings because they sell more pickups and SUVs.
The emissions of gases that contribute to climate change are also falling in cars and trucks. Carbon dioxide emissions from cars and trucks averaged 369 grams per mile last year, according to EPA, down 7 grams per mile in 2012.
Consumers are also benefitting from plunging gas prices. At $3.27 per gallon, Wednesday's average US gas prices were on par with the record low for 2014, last seen on Feb. 7.
"Gas prices have dropped about 40 cents per gallon since the Fourth of July," Michael Green, AAA spokesman, wrote in an e-mail Tuesday, "and there is room for prices to drop another 20 cents per gallon before the year is over."