There may be an alternative to an all-electric future for cars, and a way to keep classic vehicles on the road without having to replace their liquid-fueled powertrains.
The alternative is synthetic fuels.
“Synthetic fuels would be an easy fit for the transportation system because they could be used directly in automobile engines and are almost identical to fuels refined from crude oil. That sets them apart from currently available biofuels, such as ethanol, which have to be mixed with gas or require special engines,” according to a study by chemical and biological engineers at Princeton University.
“The United States could eliminate the need for crude oil by using a combination of coal, natural gas and non-food crops to make synthetic fuel,” the researchers report.
In addition to economic and national security benefits, the Princeton report said such fuel could cut greenhouse emissions by as much as 50 percent in “the next several decades.”
The university group isn’t alone in touting synthetic fuels. Automaker Porsche, technology supplier Siemens Energy and other partners have been doing synthetic fuel research and have announced a
pilot-project production plant that is being constructed in Chile to produce such fuel. Porsche plans to use the “e-fuel” in motorsports events and as part of its vehicle development program with an eye on the fuel eventually being used in production vehicles.
In a joint statement by Porsche and Siemens Energy, Porsche chief executive Oliver Blume explains notes that while “electromobility is a top priority at Porsche,” e-fuels are “a worthwhile complement… an additional element on the road to decarbonization.
“Their advantages lie in their ease of application,” he added, “e-fuels can be used in combustion engines and plug-in hybrids, and can make use of the existing network of filling stations. By using them, we can make a further contribution toward protecting the climate.
“As a maker of high-performance, efficient engines, we have broad technical expertise,” he continued. “We know exactly what fuel characteristics our engines need in order to operate with minimal impact on the climate. Our involvement in the world’s first commercial, integrated e-fuels plant supports the development of the alternative fuels of the future.”
The “Haru Oni” facility will be powered by wind energy and will “dissociate water into its two components, oxygen and hydrogen. In a second step, plans call for filtering CO2 out of the air and then combining it with the green hydrogen to form synthetic methanol. The result is renewable methanol, which can be converted into climate-friendly fuel using an MTG (Methanol To Gasoline) technology to be licensed and supported by ExxonMobil,” according to Porsche and Siemens Energy.
Plans call for the pilot project in Chile to produce around 130,000 liters (35,000 gallons) of e-fuels in 2022, and as much as 550 million liters (145,000 gallons) by 2026. The 2026 target would produce enough fuel for 1 million vehicles to be driven for a full year, Siemens Energy notes.
The Princeton researchers said production of synthetic fuels is neither easy nor quick, and they estimate it could take 30 to 40 years for the US to fully adopt such fuel.
“The chemistry is complicated, but it basically takes the carbon and hydrogen from the feedstock (such as switchgrass) and reassembles them into the complex chains that make up fuels like gasoline and diesel.”
The needed raw materials are headed to as much as 1,300 degrees Celsius and are converted into a gas which is converted into the necessary hydrocarbon molecules and that processed over catalysts to produce not only fuels, but lubricants and waxes. As part of the process, CO2 generated in the system could be recycled by being vented to feed feedstock plants.
Part of Porsche’s interest in synthetic or e-fuels is the fact that 70 percent of all vehicles it has produced are still in use and e-fuels may be a way to keep them there in the future.
“This technology is particularly important because the combustion engine will continue to dominate the automotive world for many years to come,” Porsche board member Michael Steiner said in a statement several months ago. “If you want to operate the existing fleet in a sustainable manner, e-fuels are a fundamental component.”