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EPA announces standards for light-duty vehicles; heavy-duty standards coming next

Last week, the EPA announced national tailpipe emission standards for passenger cars, light-duty trucks and medium-duty vehicles for model years 2027 through 2032.

Although the announcement focused on cars and light-duty vehicles, the EPA’s Phase 3 final rule on emission standards for heavy-duty vehicles recently passed review from the White House’s Office of Management and Budget, which means the final rule for heavy-duty vehicles should be published soon.

Light- and medium-duty standards

Under the Clean Air Act, the EPA is establishing new, more protective tailpipe emission standards for criteria pollutants and greenhouse gases for light-duty vehicles and medium-duty vehicles that will phase in over model years 2027 through 2032. In addition, the EPA is finalizing GHG program revisions in several areas, including off-cycle and air conditioning credits, the treatment of upstream emissions associated with zero-emission vehicles and plug-in hybrid electric vehicles in compliance calculations, medium-duty vehicle incentive multipliers, and vehicle certification and compliance.

Additionally, the EPA is establishing new standards to control refueling emissions from incomplete medium-duty vehicles, and battery durability and warranty requirements for light-duty and medium-duty electric and plug-in hybrid electric vehicles.

The final rule is scheduled to take effect 60 days after it is published in the Federal Register.

Heavy-duty proposal

Back in April, the EPA issued a proposed rule for setting the strictest truck tailpipe emission standards at the federal level.

The EPA’s proposed truck emission standards would require a quarter of new heavy trucks sold in the U.S. to be all-electric by 2032.

The EPA proposed stronger carbon dioxide standards for model year 2027 heavy-duty vehicles that go beyond the current emission standards that apply under the HD Phase 2 Greenhouse Gas program. The agency also proposed an additional set of carbon dioxide standards for heavy-duty vehicles that would begin to apply in model year 2028, with progressively lower standards each model year through 2032.

It is not yet clear whether the final rule will have significant changes when compared to April’s proposal.


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