In the realm of regulations governing clean trucks, the California Advanced Clean Trucks (ACT) rule has garnered significant attention since its slightly tightened restrictions went into effect at the beginning of 2025. With the possibility of other states following California’s lead, the regulatory landscape has been marked by a flurry of conflicting communications.
Unlike its counterpart, the Advanced Clean Fleets (ACF) rule, the ACT has secured the necessary waiver from the Environmental Protection Agency (EPA) to be enforced in California. This rule offers a mix of incentives and penalties to encourage original equipment manufacturers (OEMs) to produce more zero-emission vehicles (ZEVs) for sale in the state.
Meanwhile, the ACF rule is awaiting a decision on its own waiver request from the EPA, expected before the end of the Biden administration. This rule focuses on encouraging vehicle buyers, rather than manufacturers, to transition towards ZEVs.
Although the ACT technically came into effect on January 1, 2024, enforcement was paused while awaiting the EPA waiver. The widespread interest in the ACT on a national level can be attributed to the numerous states that have opted to align with California’s regulations, sparking concerns among critics about potential repercussions.
Prior to the introduction of the ACT and ACF rules, California’s stringent vehicle standards and large population raised apprehensions among automakers and engine manufacturers about the challenge of producing vehicles to meet California’s standards while also catering to other states with lower environmental requirements. This scenario, known as the “two-car” problem, has led to legal disputes over EPA waivers granted to California, with California prevailing in most cases.
Various factions have been engaged in an ongoing debate surrounding the ACT, exemplified by a series of letters and a lawsuit. State trucking associations from several states aligned with California’s rules expressed concerns to their governors about the rushed implementation timeline of the ACT, highlighting potential challenges for the industry. On the other hand, governors of ACT-aligned states defended the rule in a letter to members of the Truck and Engine Manufacturers Association, emphasizing the flexibility of the ACT and calling for collaborative solutions to increase ZEV adoption.
A lawsuit filed in Nebraska targeted prominent engine manufacturers who signed the Clean Truck Partnership with California, alleging a conspiracy to impose ZEV targets nationwide. The lawsuit underscores the uncertainties surrounding the regulations and their potential impact on the industry.
The Clean Freight Coalition, comprising trucking-related trade groups, urged engine manufacturers to reconsider their agreement with California and collaborate on national emissions standards. The coalition highlighted concerns about the impact of ZEV mandates on equipment availability and industry operations.
Amidst this regulatory landscape, questions have arisen about the tightening truck supply in California and the impact of the ACT on vehicle availability. The evolving provisions of the ACT, which include escalating ZEV sales requirements and credit-based compliance mechanisms, have generated debate within the industry. While the ACT aims to promote ZEV adoption, concerns persist regarding the availability of diesel-powered vehicles and the adequacy of infrastructure to support ZEVs.
In an effort to dispel misconceptions about the ACT, the California Air Resources Board released a question-and-answer document addressing common myths. The document emphasized the gradual transition to ZEVs while ensuring the availability of diesel-powered vehicles and the surplus of credits in the market.
Overall, the ongoing discourse surrounding the ACT reflects the complexities and challenges inherent in transitioning to a cleaner trucking industry. As stakeholders continue to navigate the regulatory landscape, collaboration and dialogue will be essential in shaping a sustainable future for the transportation sector.