A fundamental shift away from gasoline- and diesel-based transportation has begun, according to clean transportation and energy consulting firm Gladstein, Neandross & Associates in its State of Sustainable Fleets 2022, an annual survey of nearly 250 early-adopter fleets.

Sustainability — a holistic, goal-driven approach to achieving environmental, social, and business impact — has gained significant momentum in the transportation supply chain in the last several years, GNA notes. According to one analysis, 92% of S&P companies publish sustainability reports.

GNA’s survey found nearly 85% of fleets that have used propane, compressed natural gas, battery-electric vehicles, and fuel cell electric vehicles intend to grow their use of these technologies.

Alternative Fuels

Although much attention still is on battery-electric and eventually fuel-cell electric powertrains for commercial vehicles to decarbonize the industry, the past year has seen more attention to other alternative fuels that can improve the industry’s sustainability.

Cummins, for instance, announced a “fuel agnostic” line of engines, developing models designed to run on natural gas, hydrogen, propane, and gasoline.

Renewable fuels are garnering more interest, as well. Renewable diesel has a strong growth forecast in the U.S., according to GNA, especially in states with clean fuels programs such as California. RD consumption in California increased approximately 50% between 2020 and 2021 to nearly 885 million gallons.

Renewable natural gas use also grew in California, with low- or negative-carbon RNG making up 98% of natural gas used for transportation in the state. Cummins’ new 15L natural gas engine is expected to open up more applications for RNG and natural gas.

Although some predictions have been for more EV adoption among lighter medium-duty trucks, ACT Research said it’s seeing more growth in Class 6-7. ACT analysts see Class 4-5 shifting more to gasoline engines than BEV as diesel engine systems start to increase in cost as a result of the 2027 EPA lower NOx regulations. And, in fact, Cummins recently showed reporters a gasoline version of its B6.7 engine.

Zero-Emission Trucks

The COVID-19 pandemic and the continuing supply-chain difficulties affecting truck production interrupted the momentum of medium- and heavy-duty truck deployment, according to Calstart in its Drive to Zero report. Truck sales have declined by 37% since 2019 due to COVID-19. In 2020, sales dropped by 18% and fell another 23% in 2021. Despite this, medium- and heavy-duty ZET sales have increased year or year. Since January 2017, annual MHD ZET sales increased year over year by 78% in 2018, 26% in 2019, 65% in 2020, and 155% in 2021, according to the report.

However, battery-electric Class 4-8 vehicles already show positive total cost of ownership compared to conventional vehicles in three-quarters of the commercial vehicle applications examined by ACT Research in its 2022 Charging Forward report. By 2030, the research firm says, that will rise to 100%. And by 2040, ACT predicts 50% of vehicle applications will reach price parity between BEV and conventional powertrains. In fact, the firm projects that battery-electric vehicles will make up more than half (51%) of the Class 4-8 vehicles sold in the U.S. and Canada by 2035. Regulations will help push adoption rates, ACT said, but over time, technology gains will far exceed regulatory requirements for increasingly favorable TCO.

Average Vehicle Emissions Rates Per Heavy-Duty Vehicle 

Calstart’s Drive to Zero report found that model availability and driving ranges for zero-emission trucks are improving year-to-year. Greater range opens up more applications to BEVs.

GNA notes in its report that larger scale heavy-duty BEV projects are emerging, and many of its surveyed fleets will go from a handful of units in 2021 to dozens and even hundreds in 2022 and 2023. However, vehicles, batteries, and infrastructure costs have not fallen as fast as expected.

ACT is not as bullish on hydrogen fuel cells as it is on battery-electric, saying FCEVs are challenged by durability and costs.

The report said in its Class 8 day-cab application model, fuel-cell electric vehicles will eventually offer better TCO than diesel, but not better than battery-electric. In the meantime, an internal-combustion-engine powertrain will have better TCO than either BEV or FCEV for this application until NOx regs tighten.

GNA noted that while no commercial FCEVs were delivered to fleet customers in 2021, vehicle orders quadrupled across the transit and HD tractor segments, and the largest demonstrations and orders for Class 8 FCEV trucks in the U.S. to date were initiated.

In 2021, an estimated $5 billion in public incentive funding was made available to replace vehicles or expand fleets with clean alternatives, an increase from the average $3 billion that had been made available annually in the last couple of years. GNA predicts that funding in 2022 and during the next five years will shatter all prior records, boosted in no small part by the IIJA’s $1.2 trillion in federal funding and substantial increases in funding in California.

Zero-Emission Truck Sales Regulations

States with major ZET sales regulations, 2017-2022

This data and analysis first appeared in the August 2022 special Fact Book issue of Heavy Duty Trucking.

[Editor's Note: This article was updated on Sept. 12 at 5:10 p.m. CT to clarify that while overall truck sales have declined, zero-emission truck sales have increased.]