California Advanced Clean Fleets Rule Highlights

Published on
Jun 22, 2023
Written by
Jonathan Colbert
Read time
5 min
Thanks for joining our newsletter
Oops! Something went wrong while submitting the form.

The Advanced Clean Fleets Rule: What You Need to Know

This blog post is intended to provide a high-level understanding of California’s Advanced Clean Fleets Rule and some of its implications for fleets operating in the state.

Last month the California Air Resources Board (CARB) unanimously adopted the Advanced Clean Fleets regulation, which sets zero emission vehicle (ZEV) purchase requirements for drayage, high priority, and public fleets – including federal fleets – as well as a ZEV manufacturer sales mandate for medium- and heavy-duty vehicles. The rule seeks to advance the market for zero emission vehicles and infrastructure in its mission to “ensure that Californians have the clean air that they want and deserve.”

CARB expects the rule to deliver a net cost savings of $48 billion to fleets.

ACF “is anticipated to reduce greenhouse gas emissions from the state’s trucking fleet by nearly 330 million metric tons through 2050, roughly equivalent to taking 90 coal-fired power plants offline for an entire year,” according to the Union of Concerned Scientists. CARB expects the rule to deliver a net cost savings of $48 billion to fleets and save $26.5 billion in statewide health benefits from criteria pollutant emissions.

What fleets need to know

Which fleets are subject to this regulation:

• Fleets performing drayage operations; state, local, and federal government fleets; and fleets with $50+ million in gross annual revenues or control of 50+ vehicles

• Medium- and heavy-duty on-road vehicles with a gross vehicle weight rating greater than 8,500 pounds, yard tractors, and light-duty mail and package delivery vehicles

Requirements for drayage fleets:

• Beginning January 1, 2024, only zero-emission drayage trucks may register in the CARB Online System (registration is required to conduct drayage activities in California). Legacy drayage trucks in the system before then can continue to operate through their minimum useful life.

• By 2035, all drayage trucks entering seaports and intermodal railyards are required to be zero-emission.

Requirements for high priority and federal fleets:

• Beginning in 2024, fleets must purchase only ZEVs. Starting January 1, 2025, fleets must remove internal combustion engine vehicles at the end of their useful life. (This is referred to as the Model Year Schedule.)


• Fleets may elect to meet ZEV targets as a specified percentage of the total fleet starting with vehicle types that are most suitable for electrification. (This alternative to the Model Year Schedule is referred to as the ZEV Milestones Option).

Requirements for state and local government fleets:

• Beginning in 2024, 50% of vehicle purchases must be zero-emission; by 2027, 100% of vehicle purchases must zero-emission. Small government fleets (those with 10 or fewer vehicles) and those in designated counties must start their ZEV purchases no later than in 2027.


• Fleets may elect to meet ZEV targets as a specified percentage of the total fleet starting with vehicle types that are most suitable for electrification to 2035. Starting in 2035 only ZEVs will meet the requirements.

Manufacturer sales mandate:

• Starting in 2036, manufacturers may sell only zero-emission medium- and heavy-duty vehicles.

Regulating purchases and sales

Advanced Clean Fleets is just one part of an overall approach to accelerate a large-scale transition to zero-emission medium- and heavy-duty vehicles in California. It works in conjunction with the Advanced Clean Trucks (ACT) regulation, approved March 2021, which requires manufacturers to sell an increasing percentage of zero emission heavy duty trucks into the market starting by Model Year (MY) 2024.

ACT, according to CARB, “will help ensure that manufacturers offer affordable zero emission choices to fleets, while also delivering on accelerated air quality benefits to the communities that need it the most.”

As goes California…

Six states have said they will follow California’s lead in adopting ACF rules: New York, New Jersey, Oregon, Massachusetts, Washington and Vermont, according to reporting by John Kingston at FreightWaves. Indeed, history in this industry and others suggests many other states will follow California’s lead.

“Literally the whole problem to solve”

One of the key criticisms of the ACF is the lack of fleet-dedicated charging infrastructure at scale. It’s an increasingly acute challenge for fleets (and one Voltera was born to solve), whether ZEV deployment is part of a corporate climate pledge or a response to regulation. The challenge was front-and-center at the recent Advanced Clean Transportation Expo in Anaheim, where fleet and industry leaders made comments like:

• “Trucks are the easy part. 90% of the effort needs to be put into infrastructure.” James O’Leary, VP of Fleet Services at NFI

• “Infrastructure buildouts are flailing, and we’re destined to fail until emphasis is put on meeting the charging needs of electric fleets.” John O’Leary, President and CEO at Daimler Truck North America

• “Literally the power infrastructure is the whole problem to solve, the whole bottleneck.” Alex Nicholas, VP of Operations at MHX

• “The key really is the confluence between vehicle availability and infrastructure.” Drew Cullen, Senior Vice President of Fuels and Facility Services at Penske Transportation Solutions

Indeed, when it comes to the decarbonization of transportation at scale, challenges abound, and infrastructure is one of the biggest. Voltera takes on those tough challenges. So as ACF and other policies like it take effect in California and beyond, we’ll be there to support our customers – including by helping them understand and navigate regulatory requirements and incentive opportunities. (To that end, stay tuned over the coming months for insights from our new Vice President of Government and Utility Relations Tom Ashley.)