Last week, the California Air Resources Board voted to keep its vehicle emissions standards through 2025 as part of its Midterm Evaluation of the standards. The Midterm Evaluation is a process for the California Air Resources Board, EPA, and the National Highway Traffic Safety Administration to evaluate the Corporate Average Fuel Economy and greenhouse gas (GHG) emissions standards for vehicle model years 2022-2025. The California Staff presentation and recommendations for this review are available here. The Board also voted to pursue policies to support having over four million zero-emission vehicles in California by 2030.
While the Clean Air Act generally preempts state enactment of emission standards for new motor vehicles, California regulates vehicle emissions pursuant to a waiver under Section 209 of the Clean Air Act and is allowed to have more stringent standards. The Clean Air Act also allows other states to adopt California’s standards, and about a dozen have done so.
The current California and federal vehicle GHG standards are almost identical in stringency. EPA undertook its Midterm Evaluation of the 2022-2025 standards under President Obama. EPA’s November 2016 proposed determination and January 12, 2017 final determination found that the standards are still appropriate and that a rulemaking to change the standards is not necessary. However, on March 15, 2017, EPA Administrator Scott Pruitt and Department of Transportation Secretary Elaine Chao announced that EPA plans to reconsider the final determination. Such reconsideration could result in a significant divergence between the federal standards and California standards. EPA might also seek to reevaluate the waiver that enables California to craft its own standard.