An EPA report released Wednesday shows that cars are getting better gas mileage in response to rising fuel economy standards.
Yet a roaring economy and low gas prices have put Americans on a truck-buying spree, and the EPA is working to undermine those standards.
According to its annual automotive trends report, the average new car reached a record 24.9 mpg in 2017, up from 24.7 in 2016.
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What's more, the report shows a distinct improvement in fuel economy, and a corresponding reduction in greenhouse gas emissions, since the current Corporate Average Fuel Economy standards were enacted in 2012. Over that period, the average mpg of the cars sold by 12 of the 13 top-selling automakers in the U.S. rose from 23.6 mpg to 24.9, a reduction of 20 grams per mile of carbon-dioxide.
The top performers in fuel efficiency were Honda, which hit an average of 29.4 mpg, and Mazda at 29 mpg. The study did not include Teslas, which are rated at 123 miles per gallon equivalent (Model 3), 102 MPGe (Model S), and 87 MPGe (Model X) on electricity. The study is a measure of the fuel that cars in America burn. So the gains are bigger than the report indicates.
As Americans have converted to buying more SUVs and pickups, that has lowered the average. American automakers Chrysler, Ford, and GM, which have eliminated sedans from their lineups, anchored the bottom of the ratings at 21.2 mpg for Chrysler and 22.9 mpg in a tie for Ford and GM.
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The rising fuel-economy standards through 2025 were passed early in the Obama administration, the first time fuel economy standards had been raised on cars since 1989.
EPA Administrator Andrew Wheeler has proposed freezing the standards at 2020 levels through 2026 and said last month that the agency plans to make that final by next month.
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"There are legitimate concerns about the ability to cost-effectively achieve the Obama Administration’s standards in the near future," Wheeler said in a statement to Reuters.
The fuel economy standards correspond with tightening emissions standards, which were negotiated with California, which has set its own emissions standards under an exemption in the Clean Air Act. As part of the new fuel economy proposal, Wheeler has proposed to strip California of that exemption. Twelve other states follow the California standards, and 20 have joined the Golden State in a lawsuit against the EPA over the action.
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Last Wednesday, the Trump administration implored Detroit automakers to back the EPA's proposal to force California to abide by federal standards, after the EPA cut off talks with California regulators to resolve their differences. Wheeler at the time said, 'This is not a two-way negotiation."
Under the Obama administration fuel economy regime, automakers can also buy and sell fuel economy credits, which the report detailed, showing which automakers bought credits and which ones sold them.
The automaker with the most credits to sell and those who needed to buy them were similar to those to who achieved the highest and lowest fuel economy: Honda, Nissan, and Tesla sold the most, while Fiat Chrysler bought the most. It wasn't alone, however. BMW, Jaguar Land Rover, Volkswagen, and Mercedes-Benz parent Daimler also bought credits.