WASHINGTON -- The federal government's re-examination of fuel economy standards will be strictly based on scientific data gathering and analysis, the official with direct responsibility over the EPA's greenhouse-gas emissions program said Thursday.
"Whatever we decide it's really, really important it be based on the technical merits," William Wehrum assistant administrator of air and radiation, said in a speech at the Washington Auto Show. "The engineering will give us a range of plausible alternatives, but it all begins with good analysis, good engineering assessment and good understanding of what's happening in the industry, and what we think can be done in the industry."
The deadline for the politically charged review of fuel economy and emissions standards is April 1.
The Trump administration's reconsideration involves stricter fuel economy and emissions rules for new vehicles in the 2022 through 2025 model years. The auto industry agreed to the long-range program in 2011 with the understanding that baseline assumptions about gasoline prices, consumer vehicle preferences, technology costs and other factors would be reviewed at the halfway point to ensure the program was still economically feasible.
The Obama administration finalized the next phase of standards more than a year before the April 2018 deadline, prompting automakers to petition Trump to reopen the process and angering environmentalists who argue there is an effort to roll back the standards.
President Donald Trump's decision to pull the U.S. out of the Paris climate agreement, EPA Administrator Scott Pruitt's position on climate change and an aggressive deregulatory campaign to cancel many Obama-era environmental initiatives has opponents worried the midterm review will be based on ideology.
"It's a very, very high priority of mine, and others in the federal government who are working on these issues, to ground what we are doing in good engineering and science," Wehrum stressed.
The EPA and NHTSA, which set the corporate average fuel economy standards, "have not reached any conclusions about the viability of the program or whether any changes need to be made, but if we determine that changes need to be made then I would predict that we would move expeditiously to make those changes," he said.
Wehrum said he considered it very important to maintain nationwide requirements that combine EPA, NHTSA and California standards.
He confirmed recent reports that the Trump administration has initiated conversations with the California Air Resources Board on how to retain today's compatible standards for the 2022 to 2025 model years.
In an exchange with reporters, Wehrum said he was less concerned about which agency model was used for simulating emissions thresholds and compliance costs to develop fleet standards than about inputs into the models.
"There are a variety of models you can use on these things, and as long as you do the modeling right, you should get results that can be relied on," Wehrum said. "It's not so important which one we're talking about. Whatever one we choose it's important we do it right."
Asked whether regulations should do more to encourage people to drive alternative fuel vehicles, Wehrum said consumer preferences should be considered.
"What people want matters a lot to me," he said. "I don't think the government should be in the business of deciding for people what kind of car they should drive or what kind of drivetrain it should be. If people want to buy electric then we should have a regulatory process that allows them to move into electric and not impede that, and give appropriate credit for that."