The day a farmer might look up from a field and see an airplane powered by corn ethanol is coming.

At least, that's what the attendees of the North American SAF Conference and Expo hope. The three-day, national sustainable aviation fuel, or SAF, summit launched Wednesday in downtown St. Paul, gathering national leaders across agriculture, transportation and energy sectors.

"Climate change isn't always an easy conversation to have in parts of rural America," U.S. Department of Agriculture Undersecretary Robert Bonnie said in kick-off remarks. "But SAF … creates a real opportunity to create a bipartisan consensus" across urban, suburban and rural America.

The rapidly developing industry of renewable jet fuels comprises an expansive list of feedstocks, including many agricultural row crops grown in Minnesota such as corn or oil from soybeans to restaurant cooking grease, that when combined with traditional jet fuel could dramatically drive down the carbon footprint associated with jet travel.

In November 2023, Virgin Atlantic flew the world's first SAF-powered flight from London to New York. Just months ago, the Biden administration revealed eligibility standards for a U.S. federal tax credit for producers of SAF, paying $1.25 for every gallon of SAF produced that lowers greenhouse by 50% compared to conventional, petroleum-based jet fuel.

A number of markets around the globe are also moving toward carbon-reduction strategies in aviation, which contributes 2% to greenhouse gas emissions.

"Europeans are moving forward. They're putting in regulations," Annie Petsonk, U.S. Department of Transportation assistant secretary of aviation and international affairs, said Wednesday. "We need to compete in that kind of market."

But in the U.S., rollout of the SAF tax credit hasn't come without pushback. Some environmental groups charge SAF technology producers with "greenwashing," or over-emphasizing climate benefits.

And in Minnesota's backyard, a number of farm groups, including U.S. Rep. Angie Craig, a Democrat who sits on the House Agriculture Committee, have criticized the White House rules as placing unrealistic expectations on farmers to adopt new practices, such as widespread cover crops, in order to achieve eligibility for the credits.

On Wednesday, Brad Brunner, a renewables trader with Saudi Aramco, noted that farmers may plant winter crops such as camelina or pennycress but that in northern climes such secondary crops can weaken yields for their corn or soybeans.

"Farmers are maybe tentative on growing these crops," Brunner said, during a Q&A session. "Part of the reason, of course, is most of the cropland is north of [Interstate] 70."

Still, the Biden administration has set a goal of developing 3 billion gallons of SAF annually by 2030, reducing airline emissions by 20%. By 2050, they hope to meet 100% of the nation's jet fuel needs with biofuels.

Before the conference's start, a Greater MSP-led coalition announced that Flint Hills Resources and Delta Air Lines are in the "early stages" of developing the state's first SAF blending facility at the Pine Bend Refinery in Rosemount, southeast of the Twin Cities.

"Public and private sector leaders in Minnesota are building an entirely new industry in this state to solve one of the world's toughest climate problems — decarbonizing air travel," said Peter Frosch, CEO of the coalition, in a statement.

The group, comprising Bank of America, Delta Air Lines, Ecolab, Xcel Energy and other stakeholders, also announced that an ethanol plant in Luverne, Minn., owned by Denver-based chemical company Gevo, will receive a $16.8 million grant from the Federal Aviation Administration to upgrade the facility to be able to produce SAF out of regional farmers' crops.