Powering the future: The role for internal-combustion engines in a reduced-carbon world

Internal-combustion engines (ICE) are the standard—and typically the only—power option in hundreds of applications serving every corner of the globe.

The magnitude of the global reliance on ICEs and the extraordinary challenges of transitioning to different energy systems strongly suggests a continued role for ICE many decades into the future, even as new fuels and technologies emerge, according to the Engine Technology Forum’s new white paper titled “Powering On: Internal Combustion Engines & the Clean Energy Future.”

“Our global economy relies almost solely on internal-combustion engines for all of its power and mobility needs,” said Allen Schaeffer, the ETF’s executive director. “All decarbonization technologies that are being implemented, or considered, face various limits and barriers. ICEs are uniquely positioned for the future leveraging today’s fossil fuel-based economy and adapting to tomorrow’s more sustainable one that relies on renewable fuels and dramatically reduced carbon.”

ICEs will continue to thrive and dominate most sectors of the economy for decades to come for three reasons:

Near sole reliance on ICE and its supporting infrastructure across wide sectors of the global economy for which there is no suitable alternative.

Continuous improvements in efficiency and lower emissions, as well as significant opportunities for using lower-carbon fuels that position it to compete with emerging alternatives.

Delays and uncertainties due to funding support, infrastructure, market acceptance, as well as many other factors inherent in introducing new fuels and energy systems.

“We will need an increasingly diversified energy and technology portfolio that embraces advanced internal-combustion engines with a greater reliance on low-carbon renewable liquid and gaseous fuels and hydrogen,” Schaeffer said.

ICEs are expected not only to have staying power in the marketplace, but growth for another decade or more.

Various market forecasts predict combined annual growth rates for ICE to as much as 9 percent from 2023-’30.

Though increasingly stringent future standards are designed to accelerate the introduction of zero-emissions vehicles, it is still projected that ICE technology will power one third to one-half of the new vehicle fleet in 2032.

For the largest commercial vehicles, ICE technology is predicted to be the power source for 75 percent of the new vehicles.

The staying power of advanced ICE is even more pronounced in heavy-duty off-road applications in agriculture, construction, marine, rail and power generation.

“The path to the future for ICEs is well underway,” said Schaeffer. “It involves building on past progress to meet new emissions and fuel-efficiency requirements and a considerable increase in the use of low-carbon renewable fuels like renewable gasoline, renewable diesel, renewable natural gas, biodiesel, hydrogen as well as eFuels now under development. There is no single best solution to reduce carbon emissions in all sectors, which is why we must embrace all steps toward reducing carbon—internal combustion engines are clearly part of the solution. For many sectors and applications, the immediate switch to lower-carbon renewable fuels will deliver significant greenhouse-gas and other emissions reductions faster than the time it will take for a fully renewable electric-power sector to emerge and realize electrification of the transport sector at meaningful scale.”

The market and demand for renewable biobased fuels for both spark-ignited and compression-ignition engines amount to about 5 percent of the total U.S. transportation sector energy consumption. And it is growing.

The drop-in replacement nature and variable-blend capabilities of renewable fuels increases their utility in delivering near term greenhouse-gas reductions across the entire fleet of existing and new ICE.

The paper provides a comprehensive look at this critical technology, how it is evolving and how it competes with emerging alternatives.

The major challenges for ICE are discussed, all electric and fuel-cell alternatives are identified, and technical, policy, and market issues are explored.

“Powering On: Internal Combustion Engines & the Clean Energy Future” was commissioned by the Engine Technology Forum and prepared by ECOpoint Inc. out of Ontario, Canada with Addy Majewski as the principal author.

The white paper can be viewed and downloaded through the ETF website here.