In 2012, representatives from the U.S. Environmental Protection Agency (EPA) negotiated with the auto industry, environmentalists, and other groups to establish a plan to increase the fuel efficiency of U.S cars. The new standards required the auto fleet sold in the United States to average 54.5 miles per gallon (mpg) by 2025.
Car manufacturers say that the plan’s goals may no longer be realistic because of the low price of gas and Americans’ preference for sport utility vehicles.
Yesterday, however, the EPA and its partners at the U.S. Department of Transportation announced that they will reassess the standards to see whether they remain feasible. Although the plan originally was supported by environmentalist groups and the automotive industry, car manufacturers are now saying that portions of the plan’s timeline were unfairly rushed. They also say that the plan’s goals may no longer be realistic because of the low price of gas and Americans’ preference for sport utility vehicles.
The current U.S. auto fleet averages only 36 mpg, and even many modern hybrid and fuel-efficient cars fall short of the 54.5 mpg goal. Tailpipe emissions, also regulated in the plan, account for about one third of total greenhouse gas emissions in the United States.
Supporters of the regulations worry that reassessing the standards will send mixed messages to the automobile industry, which is in the process of designing cars to meet the new standards. They also worry that any reassessment will lead to the standards’ derailment, ultimately blocking an important step in the fight to reverse climate change.
However, representatives of the automobile industry argue that an accurate evaluation is essential to forging a compromise that benefits all sides. “We believe that if carried out as intended,” they explained in a letter to EPA, checks and balances within the plan’s framework “can lead to an outcome that makes sense for all affected stakeholders and for society as a whole.”
A Quick Decision
The timeline of the plan put into action in 2012 included a “midterm evaluation” in 2017 to make sure that the standards were still achievable for cars with model years of 2022 through 2025. Following the 2017 review, EPA was to release a “final determination” stating whether any of the regulations should be changed moving forward.

After the 2016 election, the Obama administration fast-tracked the plan’s midterm evaluation and approval, declaring in early January—the week before President Trump took office—that the original standards were still feasible.
However, this final step was not done jointly with the National Highway Traffic Safety Administration (NHTSA; part of the U.S. Department of Transportation). The one-sided approval left a legal loophole in the regulation decision.
On 21 February, the Alliance of Automobile Manufacturers and the Association of Global Automakers sent a letter to EPA administrator Scott Pruitt, asking him to reconsider the regulations. Mitch Bainwol, president and CEO of the Alliance of Automobile Manufacturers and author of the letter, argued that the midterm evaluation was hasty and incomplete, pointing to the cramped timeline.
He also pointed to discrepancies between EPA and NHTSA data, saying in the letter that NHTSA’s cost estimates were about 42% higher than EPA’s in the evaluation’s executive summary.
“For the auto industry, the Final Determination may be the single most important decision that EPA has made in recent history,” Bainwol said in the letter. “All we are asking is that EPA withdraw the Final Determination and resume the Midterm Evaluation.”
Environmental Groups Push Back
Supporters of the standards argue that the EPA evaluation was sufficient, especially because the original calculations were so thorough. They worry that EPA’s hesitation to move forward with the standards indicates that the new administration intends to favor the auto industry and ease up on environmental regulations.
“An attempt to weaken the standards will start a long process of rulemaking and litigation, creating chaos for the auto industry.”
In that case, “rolling back the standards would be bad for the planet as well as consumers,” said Luke Tonachel, director of the Clean Vehicles and Fuels Project for the Natural Resources Defense Council. What’s more, he continued, “An attempt to weaken the standards will start a long process of rulemaking and litigation, creating chaos for the auto industry.” This long process could cost consumers billions of dollars at the pump as new standards are worked out, he explained.
“These commonsense standards are already working to reduce pollution from vehicles, and our transportation sector makes up about a third of the carbon pollution in the United States,” Tonachel added. “Just since the standards have been in place, the EPA estimates that over 150 million metric tons of carbon pollution have been avoided.”
California’s Role
Under the Clean Air Act, California has been allowed to establish its own stricter emissions regulations. Because California is the largest automotive market in the United States, car manufacturing companies will likely continue to strive to meet the state’s tougher standards.
“All of this pushing and pulling at the federal level is in many ways irrelevant if California is not at the table and willing to ease these car regulations,” Rebecca Lindland, senior director at Kelley Blue Book, told the Washington Post.
However, the EPA may also be poised to begin proceedings to revoke California’s exemption. In his senate confirmation hearing, Pruitt declared that he would consider California’s waivers “on a case-by-case basis.” If California’s waiver is removed, the final EPA reassessment of fuel emission standards will be applied across the entire country.
The Road Ahead
Withdrawing the final determination does not necessarily lead to an environmental setback. A new midterm evaluation may come to the previous administration’s conclusion, Tonachel noted.
EPA will announce a final decision by 1 April 2018 in accordance with the schedule set in place in 2012.
“Administrator Pruitt cannot take away the standards with a single stroke of his pen.”
Even despite Pruitt’s recent claim that carbon dioxide is not a major contributor to global warming—a position that goes against scientific consensus—“he would have to refute the robust technical record of EPA, the Department of Transportation, and the California Air Resources Board to justify rolling back the standards,” Tonachel explained.
Simply put, “Administrator Pruitt cannot take away the standards with a single stroke of his pen,” Tonachel said.
—Elizabeth Jacobsen (@elizabethj0210), Staff Writer
Citation:
Jacobsen, E. (2017), EPA reassesses feasibility of plan to increase fuel efficiency, Eos, 98, https://doi.org/10.1029/2017EO069697. Published on 16 March 2017.
Text © 2017. The authors. CC BY-NC-ND 3.0
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