The Advanced Clean Fleets rule explained

By Lauren Navarro and Tom Cackette

Update 4/11/23: This blog has been amended to incorporate changes to the proposed ACF rule made by CARB staff.  

The Advanced Clean Fleets rule is a requirement for medium- and heavy-duty fleets to purchase an increasing percentage of zero-emission trucks. The ACF will complement the previously adopted Advanced Clean Trucks regulation requiring manufacturers to sell ZEV trucks and school buses. At the end of March, the Environmental Protection Agency granted California’s request for a Clean Air Act preemption waiver for the ACT, effectively granting support to this life-saving clean trucks rule, and paving the way for the California Air Resources Board to adopt the ACF.

The CARB staff has revised its proposal to require a 100% ZEV sales requirement by accelerating it by four years, to 2036. We applaud CARB staff for proposing a stronger 100% pollution-free truck sales target that more adequately reflects the health and environmental imperative of a transition, as well as recognizing the cost benefits and technological feasibility of zero-emission vehicles. Now, CARB must vote to adopt the strengthened requirement during its next meeting on April 27, to ensure that the next generation of Californians won’t grow up breathing the nation’s dirtiest air.

We need these rules because California has some of the worst air quality in the country; these trucks make up only 6% of vehicles on the road, but they make up 73% of the nitrogen oxide from on-road vehicles that harms local health and account for 9% of the state’s greenhouse gas emissions. And because these fleets are often associated with warehouses, depots and distribution centers, more likely to be sited in already pollution-burdened communities, these vehicles have a significant hand in the disproportionate health impact faced by residents of these overburdened communities.

Replacing these trucks with ZEVs will go a long way to reducing air pollutants, climate emissions and improving public health. In addition, it will save money; the CARB analysis of its ACF proposal estimates a net benefit savings of $47 billion between 2024 and 2050, which includes $20 billion in savings to fleet operators.

Structure of the regulation

The proposed rule consists of three different purchase requirements for fleet operators: 1) for private fleets with 50 or more trucks (including federal fleets and businesses with gross annual revenue of $50 million or more regardless of fleet size); 2) for drayage trucks operating from seaports or railyards and; 3) for state and local government public fleets.

1. Private “high priority” fleets

• Starts in January 2024 and applies to heavy-duty trucks and light-duty trucks used in package delivery that operate in California.
• Two compliance options:
  • Option 1: All new vehicles added to a fleet must be ZEV. Older fossil-fuel vehicles are removed from fleet when SB 1¹ statutory useful life is reached.
  • Option 2: Fleet composition (% ZEVs in the fleet) in the following table must be met even if it means retiring a fossil-fuel vehicle otherwise exempted by SB 1 (i.e., over 13 years old and > 800K miles, or over 18 years old). Unlike Option 1, this option allows continued purchase of fossil-fuel vehicles as long as the fleet composition target is met before the year 100% ZEVs are required. Option 2 is often refered to as the Milestone Option.

 ZE Fleet Composition Requirement – Option 2

Drayage trucks

• Applies to trucks that carry cargo from California seaports and intermodal railyards.
• Common ownership and control requirements apply so shippers become responsible for compliance and individual drayage operators become “part of the shipper or broker’s fleet.”
• Trucks must be registered in CARB’s online system to have access to the ports, then:
  • Beginning in 2024, any new registrants must be ZEVs trucks.
  • Non-ZEV trucks registered prior to 2024 (legacy vehicles) can continue to operate if they move cargo at the port at least once each year.
  • However, legacy trucks are removed from the registry, beginning in 2025 if the engine in the truck is over 13 years old and has accumulated more than 800,000 miles, or is over 18 years old.
• Beginning in January 2035, all drayage trucks must be ZEV.

3. State and local government fleets

• Applies to government fleets of any size.
• Begins January 2024.
• Government fleets may opt into the fleet composition option of the high priority fleet portion of the rule.
• Requires that an increasing percentage of new vehicles purchased be ZEV:
  • 2024: 50% of new vehicles purchased must be ZEV.
  • 2027: 100% of new vehicles purchased must be ZEV.
  • Delayed start to 2027 for low population (rural) agencies.

What’s next?

In June 2021 California passed the nation’s first ZEV truck sales requirement, the Advanced Clean Trucks rule, which established that, at a minimum, more than half of new trucks sold in the state will be electric by 2035. With Gov. Newsom’s call for all heavy-duty vehicles to be zero emissions by 2045, where feasible, CARB must now adopt the ACF and its more ambitious sales target.

The strengthened version of the proposed ACF rule presents a critical opportunity to more rapidly clean up the air in California and takes a stronger step towards meeting the Governor’s climate goals, while decreasing the cost of operation for fleet owners. We have no time to waste, CARB must vote to adopt the ACF on April 27.

¹ State law SB 1 prevents CARB from requiring an existing diesel truck be removed from a fleet until it is 13 years old and has accumulated over 800K miles, or is over 18 years old. This provision delays how quickly the full transition to ZEV trucks can happen.