Could winter-hardy crops fuel airline flights of the future? U of M researchers think it’s possible

Imagine if airplanes could be powered by fuel made from a plant grown in Minnesota, and it’s better for the climate than conventional jet fuel.

Some University of Minnesota researchers have been working to develop winter crops that can be made into biofuels, plus have other environmental benefits. Their work is getting renewed attention and now, a financial boost.

“These oil seeds can provide critically needed cover on the soil over winter, to protect our soil, to protect water quality, to provide wildlife habitat,” said Mitch Hunter, co-director of the U of M’s Forever Green Initiative, which has been researching sustainable cover crops for more than a decade. 

The U.S. Department of Energy recently announced it’s awarding a $10 million grant to the U program to expand its research of winter oilseeds, including camelina and pennycress.

The plants’ small seeds can be crushed to extract oil that can be refined into different biofuels, including sustainable aviation fuel, or SAF.

“The really exciting thing about that is that modeling shows the carbon intensity, or the amount of greenhouse gases that come from using this oil as fuel, is quite low compared to fossil fuels,” Hunter said. “And they also give us those really awesome side benefits.”

Those benefits include reducing erosion, preventing nitrogen from leaching into waterways, providing food for pollinators and giving farmers additional income, Hunter said. The leftover seed, called meal, can be used as a high-protein animal feed.

“We believe they would be economically attractive for farmers as well as providing a lot of environmental benefits, but we’re still working out a lot of the kinks,” he said.

SAF interest heats up

There’s a lot of interest in sustainable aviation fuel right now, as the airline industry looks for ways to reduce greenhouse gases that contribute to climate change. 

Aviation is responsible for about 3 percent of global carbon emissions. But decarbonizing air travel is a challenge. It’s not possible to power an airplane on a long-distance flight using a battery, at least not with current technology.

A coalition called Minnesota SAF Hub has been looking to scale up production of low-carbon aviation fuel. It includes companies such as Delta Air Lines, Ecolab, Bank of America and Xcel Energy, as well as the Greater MSP Partnership. Its goal to deliver 100 million gallons of sustainable aviation fuel to Minneapolis-St. Paul International Airport by 2030.

In September, a Delta flight made headlines when it took off from MSP Airport. It was the first commercial flight to use fuel made from winter camelina.

“We fully expect that at MSP Airport in the near future, Delta Airlines will be able to proudly say every single flight — frankly, not just for Delta but for the entire industry — is fueled by some SAF,” said Peter Carter, Delta executive vice president, at the event.

Sustainable aviation fuel got another boost last week when Minnesota Gov. Tim Walz proposed expanding a tax credit for it in his two-year budget.

Source matters

SAF can be made from a variety of sources or feedstocks, including wood waste, ethanol, used cooking oil and even garbage. But environmental advocates say they’re not all equally sustainable.

“How we invest in sustainable aviation fuel is really important, and it’s critical that we make the right investments,” said Trevor Russell, water program director with the nonprofit Friends of the Mississippi River. 

Russell said he’s glad Walz is proposing to give a bigger tax credit to ultra-low carbon fuels, made from sources that offer other environmental perks, such as clean water and healthy soil.

A 2023 report found widespread adoption of camelina, pennycress and other winter cover crops could reduce nitrogen loss by 23 percent, and soil erosion by 35 percent.

“Low-carbon is not necessarily synonymous with sustainable,” Russell said. “We need to support the lowest carbon fuel options that give us the best overall environmental benefits beyond just lower emissions.”

There’s still much work to do to ramp up production of oil seed crops on a large scale. 

Winter camelina is currently grown on a few thousand acres in the Upper Midwest, largely through a commercial pilot program led by Forever Green and agri-giant Cargill.

The $10 million Department of Energy grant will allow researchers to expand their study of oilseed crops. The U of M, the Minnesota Department of Agriculture, Cargill and North Dakota State University are providing $2.5 million in matching funds.

Hunter said they’ll plant five different research sites across Minnesota and North Dakota, then gather data on how the plants perform in different weather, and how farmers could grow them with soybeans or other crops.

“What this will do is help us go from kind of the early piloting phase to what we believe will be the point of commercial readiness,” he said.

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