United Airlines plans to take on climate change with jet fuels made from sugar water, corn and garbage

United Airlines sustainable fuel
A fuel truck near a United Airlines plane at O’Hare International Airport that made a demonstration flight with passengers to Washington, D.C., on Dec. 1st partially powered by sustainable jet fuel. Michael Puente / WBEZ
United Airlines sustainable fuel
A fuel truck near a United Airlines plane at O’Hare International Airport that made a demonstration flight with passengers to Washington, D.C., on Dec. 1st partially powered by sustainable jet fuel. Michael Puente / WBEZ

United Airlines plans to take on climate change with jet fuels made from sugar water, corn and garbage

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Sugar in your morning coffee or tea fuels your body.

And, soon, it may power the next flight that you’re on.

“This is a historic day, not only for United Airlines, not only for aviation, but for the globe, because this is an important milestone along the way to making aviation truly sustainable,” Scott Kirby, CEO of Chicago-based United, said Dec. 1st before boarding a plane using 100% sustainable aviation fuel (SAF).

The demonstration flight was from O’Hare International Airport to Washington, D.C., on one of United’s new 737 Max 8 jets. For the first time, according to United, a commercial carrier with passengers onboard was using SAF, a fuel intended to slash aviation’s carbon emissions footprint.

“Climate change is the biggest issue our generation faces and our generation needs to solve. The implications if we don’t are potentially catastrophic,” said Kirby, who has made SAF a major priority for United.

The jet was loaded with 500 gallons of SAF containing sugar water and corn made by Virent, a company based in Madison, Wisconsin. The plane had SAF in one engine and conventional fuel in the other engine. Federal regulations allow airlines to use a maximum of 50% SAF on flights.

“In our process, we’re able to take basically sugar water and run it through a refining process, kind of similar to what petroleum is today, except we’ve got sugar water going in as well as some renewable gasoline and some other things as well,” said Dave Kettner, president and general counsel at Virent, a subsidiary of Marathon Oil. Virent is partnering with United Airlines and Boeing to produce SAF.

Kettner, who joined Kirby on the demonstration flight, said SAF can be used now in aircraft without any added equipment. He said it burns 35% to 75% cleaner than fuels made from petroleum.

“The fuel that’s going to be on the aircraft is what we call 100% drop-in sustainable aviation fuel,” Kettner explained. “It’s dropped in because it’s fully compatible with today’s aircrafts, and the fueling infrastructure and all the logistics, which means that there doesn’t have to be anything new [that] is going to be done for aircraft.”

Kettner believes SAF will be a game changer in the aviation industry as it tries to become greener.

“I think it’s huge because it shows that the technology is there, the fuel is there and it’s ready to go. What we need to do is make sure you know that the policies are in place that are going to help bring this technology to the forefront, and give it the opportunity to actually grow and develop into something which is going to be good for everyone,” Kettner said.

Kirby said using SAF is part of United’s goal to reduce its greenhouse gas emissions 100% by 2050.

“We are a hard-to-decarbonize industry,” he said. “We are not going to be flying big airplanes long distances with batteries. There’s not even a theoretical technology that does that. We’re going to be needing jet fuel to fly. We need to keep traveling and we need to do it … in a way that’s sustainable.”

Kirby said it will take an investment of about $250 billion by 2030 to get the aviation industry transitioning 10% of its fuel to SAF.

“This can be done, but it’s going to require all of the partners,” he said. “This can’t happen without the right government support. This is an effort that we can only solve together.”

Scott Kirby United Airlines
United Airlines CEO Scott Kirby. Matt York / Associated Press

This year, United launched its Eco-Skies Alliance program with other global companies, including Microsoft, Nike and Siemens, that collectively have contributed to buying seven million gallons of SAF in 2021. United says that’s enough to prevent about 66,000 metric tons of greenhouse gas emissions.

Illinois Congressman Sean Casten, a Democrat in the northwest and west suburbs, was also on the demonstration flight, and said Congress should provide incentives for companies to develop sustainable fuels.

“We have the technology, we have the tools, we have the people, we have the talents, especially here in the Chicagoland area where we have all of these amazing businesses,” he said. “What we need is the leadership. And the leadership comes at the federal level to make sure that we accelerate the deployment of these technologies.”

United recently agreed to buy 1.5 billion gallons of SAF from Alder Fuels, a company developing ways to convert forestry and other woody residue into sustainable fuels. The airline also is an investor in Fulcrum BioEnergy, a California company that is making SAF out of household garbage.

Earlier this year, Fulcrum finished building in Reno, Nevada, what it says is the world’s first commercial-scale plant for turning trash into low-cost, zero-carbon transportation fuels. And it’s planning to build more, including one in Gary, Indiana, that Fulcrum says would make drop-in transportation fuels using waste from northern Indiana and the Chicago area.

Michael Puente covers transportation for WBEZ. Follow him on Twitter @MikePuenteNews.