Trucking fleets must now be more open about their sustainability efforts and promote their accomplishments. That's what Mike Roeth, executive director of the North American Council for Freight Efficiency, told attendees at the recent Cummins-Meritor Pressure Systems International 2023 Fleet Event.

Roeth dug into the topic of sustainability and decarbonization and explained what it will take to continue reducing emissions or even transition directly to zero-emissions trucking.

Roeth, during the event in San Antonio, Texas, said he is hearing from fleets that their customers are quizzing them more and more about sustainability-related topics. Those include how their trucks are doing on fuel efficiency improvements, emissions, and even if they are considering alternatives like natural or renewable gas or electrification.

According to Roeth, there are three decarbonization actions that can be done now by fleets. Those are:

1. Burn less diesel through efficiency.

2. Go to zero emissions.

3. Consider alternatives.

Diesel Efficiency

“Burning less diesel is decarbonizing your fleet. Tell your customers that you have moved from 6 to 6.26 (mpg). As you improve your efficiency, brag about it, talk about it. It is part of all of this,” Roeth suggested.

He said for 13 years NACFE has been doing a lot of work around fuel efficiency, looking at axles, powertrains, tire pressure systems, aerodynamics, and other factors where diesel trucking has found performance improvement.

“We're approaching that double-digit, 10 mpg kind of number,” he added. A chart he shared depicted how the NACFE Annual Fleet Fuel Study participants’ average mpg has been above 7.2 mpg for four most recent years.  In that same time, the average for all U.S. trucks has remained near 6 mpg, or slightly higher.

NACFE, and Roeth, see 10 actions that can be taken to work toward attaining 10 mpg in trucking. Those actions are:

• Build a culture of methodically choosing technologies.

• Keep equipment well maintained.

• Implement the right axle configuration.

• Provide tools to reduce idle time.

• Educate and incentivize drivers on improving mpg.

• Buy all available tractor aerodynamics.

• Optimize cruise control and vehicle speed.

• Use downsped powertrains and automated transmissions.

• Embrace low-rolling-resistance tires.

• Adopt appropriate trailer aerodynamics.

Roeth explained any fleet can access the data collected from NACFE's Annual Fleet Fuel Study fleets at no charge. The study tracked the technology adoption of 24 fleets from 2003 through 2021 and provides a benchmarking web tool for any fleets to use to see how they compare to these fleets.

“It's an insight into how they're getting to that 10 mpg,” added Roeth.

The study also details 86 technology adoption curves and fleetwide fuel economy data and provides four findings and five recommendations.

Those five recommendations are:

• Collect and monitor fuel consumption by vehicle.

• Commit to and budget for an ongoing plan of mpg improvement.

• Develop a test route and test driver to test new technologies.

• For purchasing used equipment buy from fleets known for fuel economy.

• Do not let short-term failures derail your long-term goals.

“This isn't rocket science," Roeth said. "Have a fuel economy program in your fleet, do some testing when you can, talk to your manufacturers about what they can bring to you to help your mpg, and just get a focus on it.

"I think it is part of what our customers will be asking, you'll save some money, and you'll be decarbonizing the fleet you're working on."

Is Trucking Ready for Zero-Emissions Trucks?

Another option Roeth sees would be for a fleet to go ahead and switch now to zero-emissions vehicles, such as battery-electric or hydrogen fuel-cell trucks. Or maybe even opt for the negative carbon impact of renewable natural gas. But, for most fleets, there are still infrastructure options for most of those choices.

Every two years, NACFE organizes a Run on Less study. The first couple focused on diesel trucks and how to improve efficiency for regional and long haul. In 2021 and 2023, Run on Less focused on battery-electric trucks.

NACFE recently completed Run on Less – Electric Depot, and Roeth shared some of what has initially been learned.

During the Electric Depot, NAFCE visited all 10 participant sites, eight of which were in California. The 10 depots were operating about 850 total trucks, with 291 being battery electric.

"We're in the stages of electrifying North American trucking and Run on Less – Electric Depot represents that market,” he said. “These are some of the first electrified depots in existence and included 11 different truck OEMs with eight charger companies.”

The trucks in the study included vans and step vans, box trucks, heavy-duty terminal tractors, and heavy-duty regional haul return-to-base operations. NACFE estimated the total power requirements of all trucks in the 10 depots at 214 megawatt hours a day.

Run on Less - Electric Depot Results

Although a more comprehensive report of the study is yet to come, Roeth discussed some of the initial findings, which include:

• Small depots are ready now. Also, urban trucks also tend to have long overnight times in the depot allowing for cost-effective charging, improving their total cost of ownership.

• Large energy depots are gaining momentum, given improvements in trucks, faster charging, and improved efforts by utilities, construction companies, and others. One heavy truck in the study completed 410 miles on a single charge.

• Energizing the charging sites takes too long, and Roeth said he does not have confidence that will improve. The 10 depots experienced up to 36 months to get energized, and that forced the fleets to get creative, such as deployment of temporary chargers. Many actions need to take place to better match the availability of trucks with the need to charge them on-site, Roeth explained.

Evaluating Alternative Fuels for Trucking

“There are a lot of technologies that are emerging," Roeth said, so there are questions about why the industry is looking at alternatives such as renewable natural gas, renewable diesel, and hybridization, when battery-electric looks so promising?

"Well, it doesn't look that promising for all of the market, and it doesn't look that promising right now,” Roeth explained. “We've got some work to do over the now the next five years, 10 years, 20 years.”

So, until that market matures, and infrastructure is in place, there are various alternatives.

One example that's in the works is hydrogen as a clean renewable fuel. Cummins, among others, has demonstrated that hydrogen can fuel an internal combustion engine and not just be considered for hydrogen fuel-cell vehicles. But again, the infrastructure will be needed.

There are a lot of opportunities, some more green than others. Roeth added that some are easier to integrate into trucks than others.

“We do see electricity and hydrogen being the solution long-term,” said Roeth.  “But in the interim, we won't move directly from diesel to there. So, one question is, can our industry work towards electrification and hydrogen-electric vehicles while also doing [near-term sustainable alternatives]? I mean, can we chew gum and walk at the same time? I think we can."

A Framework for Trucking Fleets to Make Decarbonization Decisions

NACFE wants to help fleets navigate the “messy middle” of decarbonizing trucks and provides a framework fleets can use for powertrain decision making. It all begins with starting with battery-electric trucks and asking if they would meet the fleet’s needs and if the cost and timing are right.

At each stage of the decision chart, three questions are asked. Those are:

• Financial benefit?

• Sustainability?

• Availability?

If “no” is answered to any of those three questions, then the decision tree points to the next option, the questions are again repeated, and so on, and so on as the chart flows from BEV, to hydrogen fuel fell, to natural gas, to renewables/hybrids, and then to hydrogen internal combustion. If at that point, hydrogen ICE is not a valid option, then the next choice is to stay with diesel.