The U.S. Department of Transportation said yesterday the NHTSA is preparing to revise corporate average fuel economy requirements for model years 2022 through 2025.
The proposed version of those regulations, which was issued by the Obama Administration in 2012, included steady increases for each of those model years.
Among the alternatives that agency will assess, it said, is a proposal to keep fuel-economy levels at their 2021 levels for each of the four successive years.
It "may evaluate the ... 2021 standards" to ensure they "remain maximum feasible" [sic]—meaning that the NHTSA could decide to roll back even the 2021 levels.
The phrase in the announcement was highlighted in a tweet by San Francisco's Nic Lutsey.
The agency is now preparing a new environmental impact statement for the proposed revision, which must be finalized no later than April 2018.
[EDITOR'S NOTE: This article was originally published on July 26, 2017. We have updated it to reflect the possibility that the agency will also assess whether to roll back its 2021 standards, with thanks to Nic Lutsey.]
2018 Ford Expedition
Automakers have argued that the shift in consumer preference away from sedan and hatchback passenger cars to utility vehicles and light trucks makes the standards harder to meet than projected when they were drafted seven years ago.
The gas-mileage standards, set by the NHTSA, have to align with the EPA exhaust limits on emissions of carbon dioxide, a climate-change gas, which is directly proportional to the amount of fuel burned by a vehicle.
Under climate-science denier Scott Pruitt, the EPA has embarked on its own review of its 2022-2025 emission limits for vehicles.
The EPA had finalized those limits in the very last days of the Obama administration, whereas under agency rules, the NHTSA hadn't yet adopted the parallel set of fuel-economy rules.
The Trump administration has argued that the process under which they were adopted did not sufficiently address the costs and feasibility of complying with those rules.
A comprehensive Technical Assessment issued in July 2016 by the environmental agency's scientists that documented the costs, benefits, and models used for the decision found not only had automakers successfully met emission limits for 2012 through 2017, but had done so at a lower cost and using less expensive electrification than expected.
To prevent automakers from facing conflicting rules for tailpipe emissions and fuel-economy levels, lobbyists will argue it's vital to ensure that gas-mileage requirements from the NHTSA must align with emission limits from the EPA.
Pruitt's EPA is expected to revise its analysis and allow more emissions in future model years than under the current regulations. Both agencies, however, have to go through a public-hearing process and base their decisions on science.
According to a report from the Reuters news service, the Alliance of Automobile Manufacturers, an automakers' lobbying group, said, "facts need to drive public policy, including data on consumer sales, gas prices and costs of technology."
In June, New York state attorney general Eric Schneiderman announced that a coalition of 14 state attorneys general and the Pennsylvania department of environmental protection would fight any attempts to weaken the EPA's existing emission limits for 2022 through 2025 vehicles.