(CN) - Automakers have surpassed strict greenhouse gas emissions standards for a third straight year and new cars and trucks averaged 24.3 miles per gallon in 2014, the Environmental Protection Agency said on Wednesday.
Fuel economy for vehicles in the United States did not budge overall from last year's record high of 24.3 miles per gallon, but the figure still outpaces greenhouse gas (GHG) emissions standards by 13 grams of CO2 per mile - about 1.4 miles per gallon, the EPA said.
"For the third year in a row, manufacturers have exceeded the GHG standards by a wide margin," said Christopher Grunder, EPA's director of the Office of Air Quality and Transportation. "It's clear that our standards are working, spurring technology and innovation, and we are on track to achieve significant greenhouse gas reductions."
Cars' average fuel usage stayed at 27.9 mpg, while trucks increased 0.6 mpg to a new record high of 20.4 mpg. This marked the second-highest annual truck increase in the last 30 years, according to the EPA.
Trucks also gained a 5 percent market share in the country in 2014. So with automakers selling more vehicles that are heavier and produce more horsepower, the overall numbers for the U.S. fleet remained steady at 24.3 mpg, the agency said.
The EPA's preliminary numbers for 2015 show some improvements, with average fuel economy expected to rise to 24.7 mpg.
In the last 10 years, fuel economy has increased significantly, improving by 5 mpg or 26 percent overall, the EPA said. Automakers will have to meet a tougher set of standards beginning in 2017, with the eventual goal of achieving a fleetwide average of 54.5 mpg by 2025.
The Obama administration said in 2012 that automakers will face penalties if they do not meet that goal.
According to the EPA, many automakers are using pollution credits to meet regulatory requirements on fuel efficiency. These credits, which are gained in part by selling optional flexible-fuel vehicles that can run on either gasoline or ethanol, can be used to avoid penalties if the automakers do not meet the fuel-efficiency standards.
Dan Becker, director of Safe Climate Campaign, said the EPA's latest report shows that while the auto industry may tout that it's technically in compliance, automakers are not actually improving mileage and emissions.
"The auto industry is exploiting the program's loopholes to boost gas-guzzler production and thwart the rules," Becker said. "Automakers should deliver cars and trucks that meet the standards without relying on loopholes to comply with the law."
Scott Hall, spokesman for the Alliance of Automobile Manufacturers, said that the EPA's report "shows continued progress across the entire fleet," and pointed out that automakers "are deploying a range of technologies that improved measured fuel economy on standardized government tests as well as alternative methods to reduce emissions for cars, SUVS, vans and pickups."
The alliance is an association of 12 vehicle manufacturers, including BMW Group, Fiat Chrysler Automobiles, Ford Motor Company and General Motors.
"Looking ahead, keeping up this pace of increasing fuel economy will be challenging, especially since our compliance is based on sales, not what we put on showroom floors," Hall said. "Consumer purchases of fuel-efficient vehicles still fluctuate with the price of gasoline, and sales of our most energy-efficient vehicles will need to significantly rise to meet future standards."
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