California proposes more ZEV trucks; NAS calls for federal truck review

By Mike Kastner,  NTEA Managing Director
Meet our experts

This article was published in the December 2019 edition of NTEA News.

Governments are trying to take the driver’s seat when it comes to trucks that will be for sale in the future.

Recently, California Air Resources Board (CARB) proposed regulations to require OEMs to sell larger numbers of zero-emission vehicle (ZEV) medium and heavy trucks in the state. While specific to California, under existing law, other states may (and do) opt-in to California emissions requirements. CARB is expected to decide on the proposal late this year or in 2020.

According to CARB, the proposed Advanced Clean Truck Regulation is meant to accelerate the transition of Class 2B–8 vehicles to zero emissions. Manufacturers that certify Class 2B–8 chassis or complete vehicles with combustion engines would be required to sell zero-emission trucks as an increasing percentage of their annual California sales from 2024–2030. 

The rule proposes that in 2024, ZEV sales — battery electric or hydrogen-powered fuel cell electric truck/chassis — must be at least 7% of Class 4–8 straight truck sales and 3% of all other trucks. By 2030, ZEV truck/chassis sales would need to be at least 50% of Class 4–8 and 15% of all truck sales. As written, the proposal states percentages of ZEVs (and subsequently, the mix of all trucks) an OEM is required to sell in the state but does not actually require fleets to purchase them.

Is the motor vehicle industry (and its vocational customers) capable of incorporating electric into 50% of the fleet within 10 years?

Further, under the California proposal, large employers would be required to report information on shipments and shuttle services. Fleet owners with 100 or more trucks would have to report on existing fleet operations. This information, according to CARB, would help identify future strategies to ensure fleets purchase available zero-emission trucks and place them in service where suitable to meet their needs.

Another concern in the work truck industry is whether or not the required ZEV technology efficiently matches specific tasks required by a customer. Vocational truck users face a variety of duty cycles that may be conducive to electric, or possibly other fuels, and propulsion systems may be more efficient.

Charging depots for large fleets will be expensive, along with electric trucks. Will fleets be able to absorb and pass on these costs to customers? Will the electric capacity be available to large operations when they need to recharge significant portions of their fleet at the same time?

National Academy of Sciences
While California proposes ZEV truck mandates starting in 2024, National Academy of Sciences (NAS) released a report on federal Phase 2 greenhouse gas (GHG) emissions and fuel efficiency regulations. It calls for better data and a midterm evaluation of current regulations.

In 2010, NAS released Technologies and Approaches to Reducing the Fuel Consumption of Medium- and Heavy-Duty Vehicles — a report that helped shape Environmental Protection Agency (EPA) and National Highway Traffic Safety Administration (NHTSA) GHG and fuel consumption reduction regulations for trucks. These initial regulations were promulgated in 2011 as Phase 1.

As NHTSA and EPA began looking at Phase 2 options, NAS released another report providing recommendations for Phase 2 standards, which were published in 2016 and run through 2027. The most recent report focuses on a possible third phase of regulations that could be promulgated in the next decade. 

The NAS report finds medium- and heavy-duty vehicles (MHDVs) account for over 20% of U.S. transportation energy consumption. While light-duty vehicles have long been subject to corporate average fuel economy standards, MHDVs have only recently begun to be regulated at the federal level. These regulations, mandated by Congress in the Energy Independence and Security Act of 2007, require at least four years of lead time between promulgation and enforcement of fuel efficiency standards, as well as a three-year stability period once standards are in effect.

The report suggests the current regulatory structure focuses on engine and truck fuel consumption and GHG emission standards but does not seem to have great flexibility to address advanced fuels, technologies and methods of improving efficiency of freight movement.

When looking at a third phase of regulations, NAS recommends NHTSA and EPA should evaluate and quantify life cycle of GHG emissions and fuel consumption of all fuels and technologies. NAS states, “It will be critically important to incorporate a life cycle perspective in those instances where some fuel-technology pathways life-cycle emissions may lead to an increase, rather than a decrease, in emissions.”

NAS believes diesel fuel will likely remain the dominant truck engine fuel through 2030. It feels one of the most effective measures going forward would be additional use of biomass-derived fuel components. The report says renewable diesel fuel and biodiesel offer up to about 80% overall GHG reduction relative to petroleum-derived diesel.

The report calls for better real-world data in making regulatory decisions. “In dealing with MHDV fuel consumption and emissions, the question arises of whether to adopt the same regulatory approach for all classes of MHDVs or different approaches for different classes.”

NAS states NHTSA and EPA currently lack reliable data on real-world vehicles that can be used to establish a credible regulatory baseline. It recommends NHTSA and EPA should collect real-world fuel consumption and emissions data from a representative sample of trucks with priority given to those categories of vehicles with the greatest fuel consumption. Using such data, a regulatory baseline could be established to better evaluate program effectiveness and future regulatory priorities.

Similar to what the current Administration did for passenger car fuel economy standards, NAS advises conducting an interim evaluation of truck regulations in the 2021–2022 time period. Reviewing results of current regulations could help improve their effectiveness through adjustments and contribute to preparations for any upcoming regulations. 

Looking ahead
NTEA will keep members informed as any measures progress. Similarly, we will notify decision-makers of work truck industry situations where one size does not adequately fit all and regulatory approaches may need to be better tailored.

Learn more at