Separately, the EPA plans to propose by March the so-called “Phase 3” greenhouse gas standards for heavy-duty vehicles beginning and new emissions standards light- and medium-duty vehicles. Both of those rules when finalized are to take effect starting in the 2027 model year.
In December 2021, the EPA finalized new passenger vehicle emissions requirements through 2026 that reversed President Donald Trump’s rollback of car pollution cuts.
The EPA said Tuesday expects to make decisions on waiver requests by the state of California to set its own heavy truck emissions rules.
EPA opted not to finalize the heavy-duty truck GHG emissions rules in 2022 after Congress passed new incentives to speed the adoption of zero-emission vehicle. EPA believes much greater zero-emission heavy duty vehicle adoption rates are possible given the climate law’s $40,000 Qualified Commercial Clean Vehicle tax credit.
Transportation is the largest source of U.S. greenhouse emissions, making up 29 percent of emissions, and heavy-duty vehicles are the second-largest contributor, at 23 percent, the EPA said.
