The ‘Messy Middle’ On The Road To Decarbonized Trucking

In late 2019, the North American Council for Freight Efficiency used the term “messy middle” to describe the 20 years between 2020 and 2040 as the trucking industry works out the best ways for fleets to cut carbon emissions. And boy, we certainly are starting to see just that.

“Messy middle” entered the emissions conversation in NACFE’s Guidance Report, Viable Class 7 and 8 Hybrid and Alternative Fuel Tractors, which was designed to help fleet managers parse through new fuel and propulsion systems. Things have been moving so fast, I’m sure parts of it are already outdated, but the idea of that “messy middle” is not.

Case in point: One option that was not in that 2019 report was the use of hydrogen as an alternative fuel for use in internal combustion engines. But Werner Enterprises will be testing such an engine later this year in its fleet, as part of Cummins’ new “fuel-agnostic” strategy. The company’s B, L and X-Series engine portfolios for medium- and heavy-duty vehicles will see the addition of versions that operate on alternative fuels to diesel, such as gasoline, natural gas/renewable natural gas, hydrogen, and propane.

If you want to wade into even messier waters, start looking at “well-to-wheel” comparisons. Decarbonizing transport isn’t just about what comes out of the tailpipe; you also need to look at emissions for how the fuel or energy was produced and delivered eventually to the vehicle.

For instance, how clean are battery-electric vehicles if the electricity is coming from coal-fired power plants? How is the hydrogen produced for fuel-cell vehicles? The most common way hydrogen is currently made is through steam-methane reforming, a high-carbon production process resulting in what’s called “gray” hydrogen. Is that really greener than, say, a natural gas engine? In fact, NACFE concluded that one of the biggest questions for the adoption of fuel-cell trucks is the source of hydrogen — although there are plenty of companies working on increasing the production of “green hydrogen” from renewable energy by electrolysis of water.

Renewable natural gas, when created from waste methane from landfills or dairy operations, actually has net-zero carbon. Not only are you reducing emissions on the vehicle itself, but you’re also capturing methane, another harmful greenhouse gas, so it’s not going into the atmosphere.

Looking at well-to-wheel comparisons, I have to wonder if the regulatory push for “zero-emission” vehicles is short-sighted. Wouldn’t it be better for our planet to look at the broader view? Why force a move to electric vehicles if renewable natural gas in internal-combustion engines actually results in lower overall greenhouse gas production?

The fact is, there’s a lot we could be doing now to decarbonize the industry while battery-electric and fuel-cell-electric technologies and their charging/fueling and support systems mature. Even buying newer, cleaner-burning, more-fuel-efficient diesel engines. Maybe the federal government should incentivize the purchase of these newer, cleaner trucks by dropping the federal excise tax. (As soon the truck makers can catch up on current demand, anyway.)

Battery-electric or hydrogen fuel-cell or both may indeed be the future of commercial transport decarbonization. But there’s a long, messy road to get there. And it looks like there are now, and will be, many options for fleets looking to be more sustainable without making the EV jump. The key is figuring out which is best for your particular operations.

Cummins’ “fuel-agnostic” approach doesn’t mean it’s any less enthusiastic about electric trucks, whether battery or hydrogen. (Just a week after its Feb. 14 announcement of the fuel-agnostic engines, Cummins announced it’s acquiring Meritor to accelerate electrification efforts.) It’s just that we can’t afford to wait for all the factors to come together for widespread EV adoption.

Calling climate change “the existential crisis of our time,” Srikanth Padmanabhan, president, Cummins Engine Business, said that “getting to zero is not a light-switch event. Carbon emissions that we put into the atmosphere today cannot be taken back. This means anything we can do to start reducing the carbon footprint today is a win for the planet.”

This editorial commentary first appeared in the March 2022 issue of Heavy Duty Trucking.