To cut greenhouse gas emissions from airplanes, the Biden administration issued guidelines last week that could shape U.S. farming for decades by offering corn growers tax credits to turn their crop into jet fuel.
To qualify, farmers would have to do three things on the land where they grow the corn: plant cover crops, avoid tilling the soil and use "enhanced efficiency" nitrogen fertilizers. Those could be relatively difficult hurdles for some farmers, such as those in Midwestern states, including Nebraska, where cover crops are rarely grown.
Corn farmers had hoped for easier access to the tax credits, and said they will push back against the requirements. Environmental groups and some scientists, meanwhile, said the incentives may only cement corn's dominance on the landscape and encourage the destructive plowing of more grasslands, woodlands and marginal farmland to grow it.
The Biden administration wants the U.S. to produce 3 billion gallons of airline fuel a year from biofuels that are created from any kind of crop or biomass that emits at least 50% fewer emissions than traditional jet fuel. The 2022 Inflation Reduction Act promised producers of those crops a tax credit of between $1.25 to $1.75 per gallon, a potential windfall for corn growers.
But the law wasn't clear about whether corn-based ethanol would qualify. It left it up to federal agencies to analyze whether the totality of emissions created by turning corn into "sustainable aviation fuel," which requires extensive amounts of land, water and fertilizer, could meet the 50% reduction threshold.
Under the new guidelines, corn growers would qualify so long as they adopted the "bundle" of all three land practices.
The incentives are an important stepping stone that acknowledge "the important role farmers can play in lowering greenhouse gas emissions," U.S. Secretary of Agriculture Tom Vilsack said in a statement. "This is a great beginning as we develop new markets for sustainable aviation fuel that use home grown agricultural crops produced using climate smart agricultural practices."
Corn growers from around the Midwest had hoped to find a new end-user for ethanol processed from their row crops, amid fears that as more electric vehicles and hybrid cars are put on the road demand for ethanol gasoline will fall. Air travel could provide an almost insatiable demand for the corn-based fuel for the foreseeable future. Airplanes are responsible for about 2% of the country's greenhouse gas emissions.
Ethanol lobbyists praised the administration for keeping intact the industry's preferred model to calculate the life-cycle emissions of corn ethanol. But corn growers said they will push back against the cover crop and no-till requirements. Only about 4% of Nebraska farmers use cover crops.
The Nebraska Corn Growers Association was critical of the announced requirements.
“This announcement sets Nebraska farmers back, as corn should continue to be a viable source of low-carbon feedstocks for ethanol and ultimately sustainable aviation fuels,” Chris Grams, president of the Nebraska Corn Growers Association, said in a statement. “The guidance has very limited positive outcomes for Nebraska farmers and farm families, as it forces voluntary practices to become mandatory for farmers across Nebraska’s variation of environments where the practices may not be feasible.”
During an Appropriations Committee hearing on Wednesday, Nebraska Republican Sen. Deb Fischer called sustainable aviation fuel, "another important potential market for Nebraska's biofuels."
But she also criticized the required land practices, saying they appear to "to mandate a set of conservation practices that corn and soybean farmers must do in order for the SAF to qualify for the tax credit."
Fischer also said in her testimony that the rules for U.S. corn and soybean farmers to qualify for the SAF tax credit seem to favor foreign sources of biofuels.
"With this updated modeling, corn- and soy-based biofuels, even if they complete the additional conservation practices, would still be deemed more carbon intensive than Brazilian sugarcane ethanol," she said.
"My concern is that this is going to lead to taxpayer dollars incentivizing imports of foreign fuel."
The tax credits will do little to actually make a dent in greenhouse gas emissions and will likely only make them worse, said Jason Hill, a professor and biofuels expert at the University of Minnesota.
Hill said the science is still out on whether cover crops or adopting no-till practices do anything to reduce emissions. If those practices do help, any benefits would be marginal compared to the carbon cost of plowing grasslands or uprooting perennial crops to grow corn.
"This provides yet another revenue stream to corn production, another giveaway to farmers and the agricultural industry at a significant cost to taxpayers and to the environment," Hill said. "We already grow an awful lot of corn. This will likely encourage further expansion of corn acreage and the intensity of corn production. And it doesn't do a whole lot to improve the footprint of corn."
There is both promise and danger to the Biden administration's strategy, said Trevor Russell, water program director for water quality advocacy group Friends of the Mississippi River.
Ethanol could cut emissions in skies and serve as a bridge until a market can be developed to grow biofuels made from perennial crops that are less harmful than corn, he said.
"But the downside is this could come at the expense of a significant increase in row crop acres," he said. "The big question is how do we avoid those landscape conversions?"