The California Air Resources Board (CARB) has opened a second 15-day public comment period to recommend additional changes to the proposed amendments for the Advanced Clean Trucks (ACT) regulation. These modifications were discussed at the October 24 CARB meeting, after which the Board directed the Executive Office to take this action.
Among the proposed changes presented is a provision to provide needed flexibility for 2026 model year (MY) California-certified heavy heavy-duty combustion engines. Specifically, manufacturers would not accrue deficits for on-road vehicles sold in California if the engines meet the nitrogen oxide emission standards set by CARB’s Heavy-Duty Engine and Vehicle Omnibus Regulation (Omnibus).
The Omnibus regulation requires heavy-duty vehicles starting in MY 2024 to meet stringent nitrogen oxide (NOx) emission limits, ultimately leading to a 90% reduction in the NOx limit. Staff’s proposed modification will support the sale of engines that comply with the Omnibus regulation without needing emissions offsets, ensuring the deployment of cleaner combustion trucks in lieu of higher-emitting engines.
According to CARB staff, this move aligns with the goals of the Advanced Clean Trucks and Advanced Clean Fleets regulations, as it doesn’t reduce the number of zero-emission vehicles (ZEVs) required.
Public comments are solicited through December 6, 2024 and can be submitted through this website. More details on the ACT and this rulemaking can be found here.