HDT's Top Green Fleets Lead the Trucking Industry in Sustainability

For most of HDT’s 2024 Top Green Fleets, improving fuel efficiency and freight efficiency are top priorities, even as they explore alternative fuels and zero-emission options.

Specs such as aerodynamics, downsped powertrains, automatic tire inflation, low-rolling-resistance tires, advanced cruise control, and idle reduction are complemented by driver training and incentives.

Freight efficiency — using fewer truck-miles to move the same amount of freight — is being improved by moving freight to intermodal, high-tech route optimization, specs designed to accommodate higher payloads, and more.

There’s increased interest in renewable fuels, with many fleets using renewable diesel, biodiesel made from waste products, and renewable natural gas.

At least three of our Top Green Fleets are piloting and/or have secured early access to Cummins’ new 15-liter X15N compressed natural gas engine, which offers fleets a closer match in performance to the diesel engines they’ve been using than previous smaller-displacement versions.

Zero-Emissions

Many of our Top Green Fleets that were waiting on electric trucks on order last year have finally been receiving them. And we’re starting to see some fleets adding electric trucks in other parts of the country than California, where adoption is being driven by regulations.

However, charging infrastructure stumbling blocks mean some of those trucks are being charged with temporary/portable charging systems.

More fleets are moving to battery-electric yard trucks and forklifts, which are a good fit for the technology, since they don’t need to worry about where the next charging station is and whether they have the range to get there.

Similarly, BEV medium-duty trucks are making their way into some of these fleets.

We’re seeing more use of solar power, whether it’s putting solar panels on warehouse roofs, creating a solar-powered distributed-energy storage system to charge electric trucks, or using solar panels on trucks themselves.

And we’re seeing more focus on fleets working with their customers to help those customers reach their own climate goals, since a fleet’s Scope 1 emissions are typically a major part of a shipper’s Scope 3 emissions.

How the Top Green Fleets are Chosen

Each year, Heavy Duty Trucking’s editors put out a call for nominations and fleet submissions to be considered for HDT’s Top Green Fleets honors. We comb through those submissions and look at factors such as:

• Adoption of alternative fuels and powertrains
• Industry-leading fuel economy
• Freight-efficiency strategies
• Leading-edge “green” facilities
• Sustainability goals
• Willingness to share their experience with others
• Other “green” awards received
• Plans for the coming year

We specifically focus on recent sustainability initiatives and progress.

For 2024, we’ve highlighted 15 fleets of various sizes and types of operations that are showing leadership in sustainability. This year’s Top Green Fleets are listed in alphabetical order.

4 Gen Logistics/Duncan and Sons

Rialto, California

Intermodal carrier 4 Gen Logistics’ fleet will be 100% zero-emission in 2025: 70 ZEV trucks now and an additional 10-14 in 2025. 4 Gen will retire its few remaining diesels in 2025, becoming the only trucking company in North America with over 70 ZEVs and no other ICE engines. Other trucking companies may have more ZEVs, but they also have many more diesel trucks in their fleets.

4 Gen is also finishing phase one of 90 high-power charging stations in the Port of Long Beach and Rialto, California. Additionally, solar and battery storage projects are currently being designed to power the ZE drayage trucks during peak and high-demand periods.

4 Gen is the sister company to Duncan and Son Lines, an 81-year-old company that primarily operates between Arizona and the ports of Los Angeles and Long Beach.

What’s Next: 4 Gen Logistics is committed to operating a 100% zero-tailpipe emissions drayage fleet by 2025. It’s planning phase two of its charging infrastructure project in Rialto, California. Ultimately, the company intends to have a total of 90 high-speed charging stations in operation between Rialto and the Port of Long Beach. The company is also evaluating the Nikola fuel-cell-electric truck.

A. Duie Pyle

West Chester, Pennsylvania

A. Duie Pyle, a primarily less-than-truckload carrier, operates 1,680 heavy-duty and 144 medium-duty trucks, and more than 3,000 trailers. Investing in fuel-efficient technologies and reducing idling time has helped Pyle save money on fuel and reduce its carbon footprint.

Pyle continues to acquire newer, smaller trucks, with 11- and 13-liter engines, for higher fuel efficiency. Self-inflating tires maintain proper air pressure that helps fuel consumption. All trucks are equipped with cruise control, with a maximum speed of 68 mph. Aerodynamic mudflaps, roof-mounted deflectors, cab extenders, and chassis side fairings help improve mpg and reduce carbon footprint.

Pyle's Parkesburg, Pennsylvania site, operates entirely on solar power. The company recycles 80% of the water used in its truck wash bays. Nearly half of Pyle’s forklifts are electric, saving an estimated 24,000 pounds of carbon emissions per unit.

What’s Next: Pyle has added 10 electric trucks and charging infrastructure at its West Chester facility to start gaining experience in operating and maintaining electric vehicles. And it plans to have nothing but electric forklifts by 2028.

Averitt

Cookeville, Tennessee

Since joining the SmartWay program in 2004, Averitt has achieved a 36% reduction in CO2 emissions, 84% reduction in NOX emissions, and saved more than 5.4 million gallons of diesel. With more than 4,700 tractors, 15,000 trailers, and 2,750 additional vehicles, that’s a big reduction in carbon footprint for the less-than-truckload carrier.

The company is converting its forklift fleet to electric at dozens of warehouse facilities, so far eliminating 13.2 million pounds of CO2 emissions annually (and rising with each additional electric forklift.)

Other ways Averitt has improved fuel economy and freight efficiency include auxiliary power units, automatic idle shutdown, Transtex trailer skirts, more efficient routing, and cruise control that features eco-roll and coast modes.

Facilities feature LED lighting, oil recycling, repairing and repurposing tires, and digital solutions that drastically reduced paper use.

What’s Next: Averitt has formed a cross-departmental Sustainability Steering Committee to gather ESG data from its vendors and suppliers. It’s working with a third-party consultant (TRC) to help it align metrics and reporting within the SASB reporting standards, including developing SASB-compliant Scope 1 and 2 reports.

DB Schenker Land US

West Memphis, Arkansas

The former USA Truck operation is a for-hire regional and long-haul operation with 2,000 heavy-duty tractors and 6,300 trailers. It currently has two battery-electric trucks and fuels some of its fleet with renewable diesel.

The company works closely with the OEs on best MPG engine parameter settings and fuel-efficient transmission and rear-end ratio specs. It has incorporated solar panels, MirrorEye camera systems, Smartway-approved tires, and the best aerodynamic packages available.

Its facilities feature low-energy LED lighting and carefully managed shop interior thermostat settings. It’s using smart chargers for battery recharging stations, eliminated purchasing fossil-fuel-burning boost-off equipment, and has moved instead to capacitor jump start equipment.

What’s Next: In 2024/2025, Schenker looks to expand battery-electric solutions into the box truck delivery market as customer needs/requirements dictate, as well as watch hydrogen solutions extremely closely. Also coming is an e-axle trailer. Carbon neutral by 2040 is the current company target.

Detmar Logistics

San Antonio, Texas

Detmar operates 180 tractors, 75 of them running on renewable natural gas, with 10 hybrid-electric. The fracking sand transportation operation has completed its order of 70 compressed-natural-gas tractors and established a purpose-built shop for its CNG-powered assets with a driver lounge.

A public renewable natural gas station built in partnership with Chevron’s Beyond6 was completed in February. Adding the fueling station helped reduce idle time and improve and efficiency. Idle management is spec’ed for all assets, with auxiliary power units.

Detmar is improving freight efficiency by helping customers source sand from closer mines, reducing miles, and adding high-capacity trailers.

What’s Next: Detmar plans to expand its number of RNG tractors and explore adding another fueling station. Its goal is to reduce over 1 million gallons of diesel and reduce GHG emissions with CNG/RNG.

Knight-Swift Transportation

Phoenix, Arizona

Knight-Swift is one of the largest for-hire carriers in the country, with 27,000-plus Class 8 trucks operating local, regional, long-haul, intermodal, and warehousing. 10,000 of those trucks use renewable diesel; three are renewable natural gas, and 23 are battery-electric. There are 100 medium-duty trucks using biodiesel, plus electric yard trucks and forklifts.

2023 brought expansion of Knight-Swift’s electric heavy-duty vehicle deployment, now in two states. It launched its pilot Cummins X15N natural gas truck and will continue that test through 2024. Increased focus on renewable diesel procurement and blended biodiesel also brought gains in 2023.

The company maintains a low average tractor age across the company. Sleeper truck idle control technology is now at or near 100%, greatly limiting idle time.

What’s Next: Increased usage of renewable and bio-blended diesel fuels, further pilots of hydrogen-powered local/regional haul vehicles, and deployment of microgrid (solar and battery) electric vehicle charging. Additional battery-electric yard trucks and day cabs will be deployed across multiple fleets. Its goal is a 50% reduction in grams-per-mile of CO2 by 2035 as compared to the 2019 baseline year.

M&M Cartage

Louisville, Kentucky

M&M is a smaller company with big sustainability efforts. The for-hire, regional haul carrier operates 278 trucks. Of those, 116 are running compressed natural gas, 162 use biodiesel, and in 2023, M&M added six new battery-electric trucks, bringing its total to eight.

M&M improved overall fuel economy from 6.4 mpg in Q4 2022 to 6.62 a year later — a 3.4% improvement. CNG mpg also increased, 6.6%, from 4.27 in Q4 2022 to 4.55 in Q4 2023.

The company credits driver training on fuel-efficient driving habits and reducing idle times.

For freight efficiency, M&M Cartage uses operations software to eliminate empty miles and pair freight.   

M&M Cartage’s campus uses LED lighting, geothermal heating and air-conditioning, radiant floor heating, energy-efficient windows, high-efficiency water fixtures, and extra insulation in ceilings and walls, cutting Scope 2 emissions nearly in half.

In partnership with Kentuckiana Clean Fuel, M&M maintains and operates CNG fuel stations in Louisville, Kentucky, and Sharonville, Ohio.

What’s Next: Growing its electric and natural gas fleet. M&M worked closely with Paccar and Cummins to secure early access to the new Cummins X15 engine, to be delivered this year.

NFI

Camden, New Jersey

This for-hire fleet offers regional, long haul, intermodal and warehousing services with a fleet of 4,900, 3,350 of which are heavy-duty. NFI is reducing its carbon footprint by operating electric trucks and electric yard horses, as well as near-zero compressed natural gas trucks fueled with renewable natural gas. It also has been transitioning fleets to biodiesel/renewable diesel and reducing idle time with weekly reporting.

NFI recently celebrated the delivery of 50 battery-electric Class 8 day cab trucks and is adding 40 more BEV trucks and 11 electric yard tractors in 2024.

Strategies for improving fuel economy and freight efficiency include five-year trade cycles, limited top speeds, low-rolling-resistance tires, tire pressure monitoring systems, weigh station bypass, and idle monitoring/reduction with APUs for sleepers. NFI's proprietary tools use up-to-the-minute data, including weather and traffic, to optimize routes.

The company is retrofitting its owned properties with LED lighting and has been installing solar panels on several warehouse facilities.

What’s Next: In 2024 NFI will operate its first electric tractors on the East Coast through the NYSERDA FEaST grant, with four Freightliner eCascadias that will service the NYC metro area.  It also will pilot its first hydrogen fuel cell tractor. And it’s adding 1MW of solar and 7.7 MWh of battery storage to its Ontario, California, charging site.

Nussbaum Transportation

Hudson, Illinois

With more than 500 Class 8 tractors in long-haul and regional operations, Nussbaum’s sustainability strategy focuses on maximizing fuel efficiency. In 2023, it achieved an average 9.1 mpg.

It starts with fuel-efficient specs. Freightliner Cascadias are outfitted with 15-liter Detroit engines, DT12 automated transmissions, and wide-base tires. A 6x4 axle spec with 2.16 rear-end ratio for better downspeeding is now on 87% of tractors. New 2024 model year trucks have a Detroit air suspension system with a steer axle that drops 1 inch at 55 mph for increased aerodynamics.

Additional aero devices are on both tractors and trailers, as are automatic tire inflation systems to reduce rolling resistance.

In 2023, Nussbaum averaged an astounding 80% “cruise control on” across the fleet.

Merlin Solar panels recharge truck and APU batteries for less idle time and longer battery life.

Nussbaum is always testing. Recent tests include lithium-ion batteries for APUs; more fuel-efficient Michelin tires; a low-ash oil to reduce aftertreatment regens; longer cab extenders that deploy at 55 mph; the MirrorEye mirror camera system, and more.

Nussbaum incentivizes and teaches drivers the skills that lead to fuel efficiency. Its Excelerator Scorecard measures drivers on smoothness, speed usage, throttle, space management, idle time, maintenance, and more.

What’s Next: Nussbaum plans to continue working toward 100% 6x4 trucks and phasing out 60-inch midroofs in favor of 72-inch midroofs with electric APUs. It will continue to test new technology. Its 2024 idle time goal is 10% or less and fleet mileage at 9 mpg or above.

Old Dominion Freight Line

Thomasville, North Carolina

A major less-than-truckload carrier with more than 11,000 trucks, ODFL works with its OEMs to customize equipment and evaluate new technologies. It operates one of the newest, most efficient LTL fleets in the country, with an average tractor age of 4.5 years. Fuel-efficiency tools are used on tractors and trailers such as air dams, deflectors, trailer skirts, and auto-inflating, low-rolling resistance tires. It operates its newest, most efficient tractors on its longest linehaul routes.

Drivers get fuel-efficiency training, focused on progressive shifting, reducing idle time, and maintaining consistent speed. Efficiency performance is measured by a telematics system.

While it owns one Class 8 battery-electric tractor, the company said it hasn’t yet found a zero-emission tractor that meets its requirements for range, hauling capacity, utilization, and cost. The fleet uses biodiesel and renewable diesel products where available at competitive costs.

The carrier gains efficiencies via dual use of tractors in both linehaul and pick-up and delivery (P&D) routes and maximizing route planning efficiencies through technology. Where allowed, longer combination vehicles are used in linehaul to maximize cargo per load mile.

OD has invested heavily in energy efficiency for new and renovated service centers. In 2011, OD installed its first roof-top solar power generation system at its facility in Thomasville, North Carolina.

What’s Next: Invest and evaluate EV yard tractors and forklifts for broader roll-out and begin initial testing of EV straight trucks in 2024.

Paper Transport

De Pere, Wisconsin

This for-hire regional, intermodal and local dedicated fleet prioritizes education of its 800 drivers and incentivizes efficient driving behaviors such as reducing idle time, minimizing brake use, and selecting optimal routes. Battery-powered APUs further minimize the need for idling.    

That and integrating fuel-saving technologies into the fleet, such as aerodynamic devices and fuel-efficient powertrain packages, have helped Paper Transport average more than 8 mpg.

Paper Transport currently operates 65 compressed natural gas trucks, accumulating 80,000 miles per year per truck, and the majority of that fuel is renewable natural gas. The company has engaged in EV demonstration projects with five customers to explore sustainable transportation solutions.

A dedicated internal team has focused on reducing empty backhaul miles by 80% to improve freight efficiency. The company also uses specialty equipment to increase payload, resulting in fewer miles required to deliver the same freight volume.

What’s Next: Moving 74 million miles with natural gas and saving 114,285 gallons of annual fuel consumption through efficient driving by the end of 2024.

Schneider

Green Bay, Wisconsin

Schneider operates more than 10,000 company tractors in local, regional, long-haul, intermodal, and warehousing. Sustainability initiatives include electric vehicles, optimized shipping routes, intermodal, testing other ZEVs such as hydrogen fuel cell trucks, continuously updating the diesel fleet, and improving its facilities. Schneider also uses alternative fuels, including biodiesel from organic waste and renewable diesel.

To power its electric fleet, Schneider built a charging depot about half the size of a football field at its operations center in South El Monte, California.

Schneider ensures drivers are well-trained on best practices to mitigate emissions, including investing in simulation-based training and education programs.

A four-year trade cycle for most trucks gives Schneider an average age of about two years in its truckload divisions. It has adopted a lower rear axle ratio for further engine downspeeding, reduced drag with an updated rear fairing system, and installed electric-powered HVAC systems. It’s continuing its pilot of the MirrorEye camera monitor rearview system to improve aerodynamics.

Schneider uses intermodal to offer another way customers can reduce the carbon impact of their shipments. A ton of freight can be shipped 500 miles on the equivalent of a single gallon of fuel.

The company works with customers to understand, measure and reduce their Scope 3 emissions.

What’s Next: Schneider’s goal is to reduce CO2 per-mile emissions by 7.5% by 2025 and 60% by 2035. It will continue to focus on expanding its fleet of BEVs and enhancing the energy efficiency of its fleet and facilities. It’s also working toward doubling its intermodal size by 2030.

System Freight

Jamesburg, New Jersey

As a Northeast regional dedicated carrier, System Freight operates fleets that park at customer facilities. Infrastructure to deploy alternative fuel equipment is extremely limited in the Northeast, so System Freight focuses on the newest technology spec vehicles in its 500-truck fleet, with downsped and turbo compounding engines and clean-burning fuel-efficient engines, while it waits for zero-emission truck technology to advance to a point where it’s feasible in their operations.

It recently added 219 new custom-spec high cube "wedge trailers" that allow paper mill customers to load tall rolls of paper, effectively shipping seven trailer-loads of freight on six trailers.

What’s Next: By the end of 2024, 90% of the fleet will be model year 2023 or newer, all highly fuel efficient. SFI’s goal is to exceed an 8 mpg fleet average as it enters the second quarter of 2025. Operating in a densely populated Northeastern region, this is a big goal. And it recently completed a demo test averaging over 9.1 mpg with the new International S13 integrated engine and drivetrain platform and will be adding it to its fleet. 

TCI Transportation

Commerce, California

TCI offers dedicated logistics as well as leasing and rental services for primarily heavy-duty trucks. It has hundreds of electric trucks on order, including 20 Tesla tractors, 100 Kalmar T22 electric yard tractors, and about 20 electric Class 4 bobtails from GreenPower and Evolectric. Some of these trucks will be leased out to customers, but others will remain in the TCI fleet.

It has installed several EV chargers in its Fontana and Commerce facilities in California and has ordered more Detroit eFill chargers to install at others in the state. 

The company works to improve fuel economy and freight efficiency by working to send out a truck or trailer loaded with a shipment instead of running empty miles.

In addition to electrifying its fleet and providing customers with EV education, TCI has installed solar power facilities in three of its 10 locations so far.

What’s Next: TCI plans to further electrify its fleet as well as those of its customers. It currently has a few electric TCI Service Trucks and plans to switch them all over to electric within the next coming year.

Werner Enterprises

Omaha, Nebraska

Operating nearly 8,000 trucks in long-haul, regional, intermodal and delivery operations, Werner actively tests and implements alternative fuels and technologies.

Its fleet, averaging 2.1 years in age, benefits from the latest fuel-efficient technologies, ensuring high efficiency and lower emissions, such as the latest diesel engines, aerodynamic packages, and automated transmissions. Auxiliary power units and computerized truck idling technology use approximately 75% less fuel than idling.

Nearly all Werner’s fuel purchases include biodiesel in the fuel blend. The company is operating a Cummins compressed natural gas test engine/truck, running on renewable natural gas, and have a letter of intent with Cummins to potentially acquire 500 Cummins X15N CNG engines.

By the end of 2024, Werner will have integrated 10 Class 8 battery-electric tractors into its fleet, and it is testing electric yard trucks in its terminals. 

At its facilities, Werner has removed refueling tanks, implemented comprehensive recycling programs, converted to LED lighting, and is exploring solar power installations and electric vehicle charging infrastructure.

The company collaborates closely with customers to help them reduce Scope 3 emissions. By 2025, Werner aims to disclose its Scope 1 and Scope 2 greenhouse gas emissions.

What’s next: Werner’s goal is to achieve a 55% reduction in greenhouse gas emissions by 2035. It will continue to expand its fleet of alternative fuel vehicles and further optimize route planning and load scheduling to minimize empty miles, and it’s exploring additional options such as hydrogen fuel cells and carbon capture technology. Werner also aims to double intermodal operations by 2030.