While much of North America is focused on electric vehicles (EVs) in the push toward zero emissions, another player is back on the field and rapidly gaining ground: the internal combustion engine (ICE).
The freight industry is grappling with the adoption of electric heavy-duty trucks for numerous reasons.
- Their limited range makes them suitable for use only where charging is accessible, typically at carrier terminals or vendor sites.
- Irregular route carriers have difficulty finding a use for vehicles that must return to the terminal each night.
- Power grid issues are problematic for carriers trying to install charging infrastructure for their fleets.
- Finding qualified technicians to keep the trucks working — and drivers to drive them — are added issues.
Luckily, advances in technology and alternative fuels are bringing ICEs back into the game.
In September, the Engine Technology Forum gathered experts from half a dozen related industries to discuss taking the ICE to the next level. They shared an encouraging message: ICE technology can deliver the lower emissions benefits of EVs more quickly, at less expense and with fewer changes to the national infrastructure.
At a minimum, the new ICEs offer a viable bridge to a zero-emissions future.
According to Allen Schaeffer, executive director of the Engine Technology Forum, reaching the goal of zero emissions in trucking requires a combination of solutions — not just a rapid-fire switch to EVs.
“Internal combustion engines, those powered by gasoline, diesel, natural gas and propane, really are key to our current economy, and we see them also as a key part of our energy future,” he said.
One method of reducing emissions that is already available is the use of biomass-based diesel fuel, according to Steve Howell, founding partner of M4 Consulting and Chair of the ASTM Biodiesel Task Force. Renewable diesel and Biodiesel are both products that Howell refers to as “liquid solar energy.”
“The major driving force now is carbon,” Howell said. “When you look at biomass-based diesel, it takes CO2 from the air to grow oil or fat. When we burn that oil or fat, there’s a net life cycle reduction of carbon in the atmosphere about 70%.”
In other words, burning petroleum-based diesel adds carbon to the air, but the process of growing the soybeans or other crops used in biomass-based fuels actually removes CO2, helping to balance the scale. The end result is a 70% reduction in total carbon emissions. The remaining 30% comprises mostly the diesel fuel burned to grow, harvest and transport the crops needed to produce the biofuel.
If the crops were grown and transported using only biomass-based diesel, that 30% could be reduced to zero, Howell noted.
Soybeans, corn, canola and animal fats can be used to manufacture biomass diesel fuel, but Howell focused on the additional benefit of using soybeans. Because the beans are 80% protein and 20% oil, the protein meal left after the oil is extracted could decrease the price of the product by $20 to $40 per ton.
Last year, about 4.5 billion gallons of biomass-based diesel were produced, about 10% of the distillate demand in the U.S. (70% in California). The industry plans to increase production to over 6 billion gallons by 2030 and 15 billion gallons by 2050.
Time, however, is of the essence.
According to Howell, atmospheric CO2 builds each year. For each five year of delay, CO2 reductions will need to increase by a factor of 13 times.
New engine and aftertreatment technologies are already reducing tailpipe emissions of NOx and particulate matter to near-zero levels. Replacing the current mixture of biomass-based and petroleum-based fuels with 100% biomass-based fuels will soon be viable options for low-carbon combustion.
Fuel additives also play a part in emissions reductions, according to Mary Dery, PhD, who is the performance additives technical director at Innospec.
Noting that fuel filter plugging, fouled injectors and saturated diesel particulate filters all contribute to increased emissions, Dery highlights the benefits of adding detergents to diesel fuel. Cleaner injectors, she says, provide better fuel economy and reduced DEF consumption, while cleaner particulate filters mean more time between fewer regens and less fuel use.
Propane, while not a new fuel option, has typically been used in its gaseous form. Srinu Gunturu, chief engineer at Stanadyne, is excited about advances in the use of liquid propane as vehicle fuel. By developing high-pressure liquid fuel systems and specialized direct injectors, Gunturu sees liquid propane as a bridge to achieving zero carbon.
“We believe that liquid propane is going to be a great alternative, and we see that direct injection is going to result in a huge efficiency improvement and also improved emissions,” he explained.
The fuel has lower greenhouse gas emission levels than either gasoline or diesel and close-to-zero particulate matter emissions.
“We see that liquid propane and direct injection emissions results are promising compared to diesel and gasoline, Gunturu said. “We believe that this technology will improve the efficiency of the engine significantly in the current market.”
There’s no question that the goal of zero-emissions vehicles is desirable for all forms of transportation.
The question, then, is this: Are EVs the best answer right now?
While battery power represents the cleanest option for tailpipe emissions, battery-electric vehicles won’t be truly “zero emissions” until the electricity used to charge them is also free of emissions — and that day is a long way off. On top of that, mining and transporting the rare substances needed to construct batteries for them also requires carbon emissions.
In reality, unless someone figures out how to safely install and operate a small nuclear powerplant under the hood, solving vehicle emissions will take a combination of different technologies.
Back in the early days of the automobile age, the internal combustion engine turned out to be the power choice over steam, electric and other technologies. For many applications, it still is.
Cliff Abbott is an experienced commercial vehicle driver and owner-operator who still holds a CDL in his home state of Alabama. In nearly 40 years in trucking, he’s been an instructor and trainer and has managed safety and recruiting operations for several carriers. Having never lost his love of the road, Cliff has written a book and hundreds of songs and has been writing for The Trucker for more than a decade.
