Researchers pilot new process to achieve 100% bio-based jet fuel
As the airline industry works to cut its carbon dioxide emissions, a team of researchers believe they've found a "runway" to 100% sustainable aviation fuel.
Their findings – published this week in the journalJoule – demonstrate harnessing the power of lignin. It’s a biopolymer that makes up one-third of almost all plants and wood, and it hasn’t been used much due to its rigid chemical structure that is hard to break down.
“It's a really wonderful defense,” said Gregg Beckham, a senior research fellow at the National Renewable Energy Laboratory in Golden, Colo. “It's why cows need four stomachs to get any caloric value from grass. And it’s why dead trees take many, many years in many parts of the world to degrade.”
The research comes out of a partnership among NREL, the Massachusetts Institute of Technology, and Washington State University. Their goal is to extract the lignin from waste and dead plants and remove the oxygen in it in order to create sustainable aviation fuel.
“We want to make something that you can go put into a jet engine and it's safe and it works just as well, if not better,” Beckham said.
The CO2 reductions could be huge in an industry that accounts for 3% of the national greenhouse gas production. In April 2022 alone, U.S. airlines used 1.35 billion gallons of fuel, according to the U.S. Bureau of Transportation Statistics. With each gallon of burned plane fuel emitting 21.5 pounds of CO2, that’s more than 29 billion pounds of CO2 in the atmosphere in a month.
Think of this fuel as recycled carbon dioxide. Plants take in CO2 as part of their life cycle. When the plant is converted to fuel, it still will emit CO2, but it’s emitting the CO2 that it already took out of the atmosphere.
“Say it's corn," Beckham explained. "After you harvest the corn, if you can take some of that corn stover, and turn that into biofuels, then you have a much more potentially more circular carbon economy there and potentially lower greenhouse gas emissions.”
And the Mountain West could supply those resources they need.
“Woodchips and sawdust and all of these types of biomass that are collected today potentially could be converted into these types of biofuels,” he said. “And so in that case, inherently, biofuels is a local industry.”
When Beckham and his team tested the fuel in the lab, they found that it could work at a larger scale. In a news release, they explain how in order for the fuel to be effective, the oxygen contents have to be less than a half-percent. Previous research could not come close to that number, but the team of researchers have this fuel down to 1% oxygen.
“I think this gives us a runway to work towards a viable process to valorize this polymer that's been in plants for 400 million years or 570 million years, but hasn't really – there's no market for it today,” Beckham said. “And I think it'll certainly contribute positively to the bioeconomy.”
Their team is currently talking to companies who might be interested in scaling it up, as well as doing more of their own tests in the lab for the next several years to produce a viable, cost-effective fuel option.
This story was produced by the Mountain West News Bureau, a collaboration between Wyoming Public Media, Nevada Public Radio, Boise State Public Radio in Idaho, KUNR in Nevada, the O'Connor Center for the Rocky Mountain West in Montana, KUNC in Colorado, KUNM in New Mexico, with support from affiliate stations across the region. Funding for the Mountain West News Bureau is provided in part by the Corporation for Public Broadcasting.