Sustainability is becoming more and more important to trucking. Government regulations, shipper demands, and public opinion are driving a push toward vehicles, technology, and operational shifts that improve greenhouse gas emissions and air pollution and address other environmental and societal concerns.
2021 HDT Fact Book: Sustainability Focus Not Slowed By Pandemic
The COVID-19 pandemic did not slow down commitments to sustainability in the supply chain. Interest in not only energy savings and renewable energy increased significantly. Here’s the sustainability data you need to know from HDT’s 2021 Fact Book.

Heavy Duty Trucking’s annual Fact Book is designed to provide a snapshot of the current state of the industry, where it’s been, and where it’s going. These numbers can help you in planning and benchmarking your fleet, and in telling trucking’s story to others.
Graphic: HDT
The COVID-19 pandemic did not slow down commitments to sustainability in the supply chain. Interest in not only energy savings and renewable energy, but also human rights protection, worker welfare and safety, increased significantly over the last year, according to a recent report from the MIT Center for Transportation & Logistics and the Council of Supply Chain Management Professionals.
Although the survey didn’t ask shippers and third-party logistics companies about how they plan to choose carriers in the years ahead, “for trucking fleets, I think we can read that pressures to be part of their large shippers’ sustainability efforts did not relent under the pandemic year,” MIT’s David Correll told HDT. “Given that … it seems harder than ever now to imagine a reason that this pressure would not continue.”
Walmart, for example, has committed to reach net-zero emissions from all its vehicles and its transportation network by 2040. Knight-Swift plans to cut GHG emissions in half by 2035, and FedEx announced a goal to achieve global carbon-neutral operations by 2040.

The average emissions rates per heavy-duty vehicle has steadily declined since 2005, according to the U.S. Department of Transportation’s Bureau of Transportation Statistics. BTS defines heavy-duty vehicles as those with more than two axles or four tires.
In 2021, the bureau projects emissions to be the lowest on record, and for the numbers to continue to decrease until 2030 (the last year of BTS projections in this dataset).
The emissions rates are in grams per mile, and are based on the national average age distributions, vehicle activity, temperatures, inspection/maintenance and antitampering programs in that calendar year.
Source: USDOT Bureau of Transportation Statistics
The State of Sustainable Fleets report found that in 2019 and 2020, 83% of clean-vehicle early adopter fleets plan to increase their use of natural gas, propane, battery-electric, and hydrogen fuel cell electric vehicles in the next five years. The report, produced by clean technology consulting firm Gladstein, Neandross & Associates, noted that even during the pandemic last year, the growth of clean technologies continued to rapidly accelerate. It saw an increase in fleet orders and deliveries for natural gas and battery-electric vehicles as well as for lower carbon renewable fuels.

The overall number of available zero-emission commercial vehicle models is on a strong upward trajectory globally despite the economic impacts of the global pandemic, according to Calstart’s Zero-Emission Technology Inventory. The United States will see an even sharper uptick in available zero-emission heavy-duty truck models compared to other global markets in the next few years, rising 250% from just eight models in 2020 to 28 models on the market in 2023. Last year at this time, only 16 heavy-duty trucks were expected to be available by 2023.
Source: CALSTART Zero-Emission Technology Inventory
Meanwhile, traditional diesel drivetrains continue to get greener. The Environmental Protection Agency’s Phase 2 Greenhouse Gas Standards for Medium and Heavy-Duty Engines and Vehicles went into effect with model year 2021. When fully phased in by 2027, these standards will require GHG reductions of up to 25% from MD/HD vehicles and 4-5% from engines.
But as the State of Sustainable Fleets Report points out, traditional drivetrains face increasingly stringent regulatory initiatives (including outright bans) and growing expectations from sustainability-oriented customers and the public.
Ultimately, the pace of widespread fleet adoption of new sustainable vehicle technologies comes down to whether they can compete with traditional drivetrains in terms of performance and total cost of ownership.

According to ACT Research, by 2035, about 40% of the Class 4-8 market in the U.S and Canada will be electric vehicles, with gains achieved due to a compelling business case, particularly as battery costs drop and stricter emissions regulations make vehicles with internal combustion engines more expensive.
Source: ACT Research Charging Forward Report, 2021
More Fuel Smarts

California Launching $1 Billion Electric Truck Rebate Program
CARB says the California Clean Fuel Reward program will begin offering point-of-sale rebates of up to $120,000 for electric commercial trucks starting June 26.
Read More →
Mack Unveils EPA 2027-Compliant MP13 Engine With More Power, Better Fuel Economy
Along with unveiling its EPA 2027-compliant MP13 engine, Mack outlined powertrain changes across its Class 6-8 lineup, including new Cummins-based X10 engines.
Read More →
How Volvo’s New D13 Engine Meets EPA 2027 Emissions Without Sacrificing Power or Fuel Efficiency
Volvo says advances in combustion and aftertreatment helped its new EPA 2027 D13 engine avoid the fuel-economy penalties many once expected from tighter NOx emissions limits.
Read More →
'TCO’s Here.' Tesla Says Electric Semi Economics Are Ready for the Mainstream
Tesla’s Semi chief at ACT Expo outlined production growth, lower-cost models, charging expansion, and why the company believes fleets are leaving money on the table by waiting on electric trucks.
Read More →
What Will It Take to Scale Electric Truck Charging? New Electrification Coalition Report Identifies 11 Solutions
A new report from the Electrification Coalition outlines key barriers slowing electric truck charging deployment and offers policy solutions to accelerate infrastructure growth.
Read More →
NACFE: Fleets Need to Recalibrate TCO Strategies as Electric Trucks Gain a Long-Term Edge
NACFE’s Run on Less data has found that recent setbacks aside, electric truck powertrains are trending toward market leadership by 2025.
Read More →
New High-Horsepower Natural Gas Engine Could Expand Fleet Options
Westport and Volvo are demonstrating a 500-hp truck with diesel-like efficiency — one that also offers what Westport says is a better pathway to using hydrogen fuel in trucks.
Read More →
Why Fuel Diversification Matters for Trucking Fleets
Relying on diesel alone exposes fleets to fuel price volatility. Here’s why diversification with electric, natural gas, and renewable fuels can reduce risk.
Read More →
Range Energy Confirms eTrailer Performance in Winter Testing as Commercial Rollout Nears
Range Energy said its production-ready eTrailer system proved it can boost stability, safety, and efficiency in sub-zero winter conditions as the company moves toward scaled deployment.
Read More →
Top Green Fleets of 2026: Nomination Deadline Extended
Is your company a leader in sustainability efforts among trucking fleets? If so, Heavy Duty Trucking's editors want to hear from you.
Read More →
