EPA 2027 and Beyond: How Will New Low-NOx Rules Affect Fleets?
Senate Resolution Attacks EPA's Truck Emissions Rules
Will Republicans be able to overturn the Environmental Protection Agency's latest truck emissions regulations?

EPA 2010 regulations virtually eliminated black smoke coming from diesel truck stacks, but the EPA now wants to go further.
Photo: Jim Park
Some members of the U.S. Senate aren’t happy about the latest heavy-duty truck emissions standards from the Environmental Protection Agency.
The Congressional Review Act joint resolution, aimed at rolling back the ultra-low-NOx standards finalized in December, passed the Senate 50-49 on April 26.
The resolution was led by Nebraska Republican Senator Deb Fischer, who contended that the regulation would devastate the trucking industry, raise costs for consumers, and incentivize older, less efficient trucks to stay on the road.
All 49 Republican Senators voted in favor of the legislation, in addition to Democrat Joe Manchin from West Virginia.
However, the narrow vote in the Senate fell well short of the two-thirds majority that would be needed to override a veto, which the Biden White House has already said it would do.
Thomas Carper, a Democrat from Delaware and chairman of the Senate Environment and Public Works committee, criticized the resolution, warning that it could “prevent the agency from ever issuing similar standards in the future.” Carper called the standards achievable and pointed out that they provide predictability for the industry.
“This regulation is jeopardizing our economy, and I look forward to the Republican-controlled House taking up our legislation,” said Fischer. In the House, the legislation is being led by Rep. Troy Nehls, a Republican from Texas.
Just How Bad Are the New Heavy-Duty Truck Emissions Standards?
EPA finalized its rule on new emissions standards for heavy-duty vehicles on Dec. 20. The new standards cover nitrogen oxides (NOx) and other air pollutants, including particulate matter (PM), hydrocarbons, and carbon monoxide (CO). The rule would also change requirements regarding emission control systems and emission-related warranties.
There have been a number of concerns expressed in the trucking industry about the new rules, with broad agreement that they are going to be costly and difficult to comply with.
Most of the truck and engine makers issued public statements saying they were confident they could comply. But in reality, it’s possible that none of the 2027 engines will actually technically comply, because the OEMs will use emissions credits.
“I think you’re correct that most of the engine manufacturers don’t believe that diesel engines can meet what we call the direct standard in 2027,” Patrick Couch, senior vice president of technical services and partner at clean transportation and energy consultants GNA (Gladstein, Neandross & Associates), told HDT in an interview.
“The direct standard is the 35 mg standard you would have to comply with without credits. But EPA has built into this rule the ability to generate credits for NOx, which can be used to certify engines above the direct standard from 2027 through 2034.”
There's little argument that new trucks will become more expensive under the new rules. Not so much agreement on exactly how much.
The EPA estimated the technology required to meet the new rule’s standards would cost between $2,568 and $8,304 per vehicle. The American Truck Dealers Association estimated a $42,000 increase per truck. And ACT Research VP and senior analyst Tim Denoyer told HDT that its firm’s latest thinking on the cost increase is a $20,000 to $25,000 range on the national level.
By increasing the cost of a new truck, the regulation actually incentivizes keeping older, higher-emitting trucks in service longer, according to Fischer. And indeed, industry analysts are predicting a massive pre-buy of trucks before they go into effect.
Fischer said the new emissions standards also would also likely force many "mom and pop" trucking operations out of business while encouraging larger trucking operations to pass these higher costs onto consumers.
A prebuy, you say? Watch HDT's interview with ACT's Tim Denoyer on the topic.
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