Ignoring science, undermining public trust: A concerning SAF proposal in Congress
A tax credit that ignores science could further encourage practices that harm water quality and the climate. (Photo by the Minnesota Pollution Control Agency)
A provision in the massive GOP spending bill being considered in Congress poses a real threat to the value of sustainable aviation fuel (SAF) as a viable climate solution.
It risks ushering in a worst-case scenario: SAF markets dominated by millions of new acres of summer annual row crops that are the primary source of pollution to the Mississippi River.
The proposal, from Minnesota Sen. Amy Klobuchar and Sen. Roger Marshall of Kansas, would remove a critical climate metric called “indirect land use change” when calculating which sources of lower-carbon jet fuel qualify for a lucrative new tax credit.
As detailed by the Star Tribune, this disregards science and could have serious consequences for Minnesota’s already-struggling waters and wild areas, while setting a dangerous precedent for other climate programs.
The details: How federal SAF funding works
In 2021, the federal government launched the Sustainable Aviation Fuel Grand Challenge. This government-wide project aims to put the aviation industry on track to reach net-zero emissions.
To reach this target, the federal government offers tax credits meant to spur SAF production. The Biden Administration’s 2022 climate bill, the Inflation Reduction Act, provides subsidies to companies producing low-emission transportation fuels such as SAF through a tax credit known as 45Z.
In order to qualify for this tax credit, SAF needs to have a carbon intensity (CI) score at least 50% lower than petroleum-based jet fuel. The lower a fuel’s CI score, the larger the tax credit.
Carbon intensity scores take into account the entire life cycle emissions of the fuel, including emissions from producing the feedstocks, transporting those materials, and the chemical conversion process that produces SAF.
When the feedstock used to produce a biofuel is an agricultural crop, this calculation of lifecycle emissions also measures emissions associated with something called indirect land use change (or, ILUC).
ILUC is how we account for the emissions consequences of converting natural lands such as forest, wetlands or prairies into cropland in response to a changing agricultural market.
Remove ILUC from the equation?
Sens. Klobuchar and Marshall have proposed to ignore the impact of indirect land use change when determining whether a new fuel is actually sustainable.
On April 10, 2025, they introduced the Farmer First Fuel Incentives Act, which removes the ILUC calculation when evaluating the carbon intensity of fuels under the federal 45Z tax credit. This provision, backed by some in the agribusiness industry, artificially lowers the carbon intensity of crops like corn and soybeans.
This, in turn, allows them to qualify more easily for the 45Z tax credit — without actually having to implement the types of sustainability practices that will protect our water, natural lands and wildlife.
(We should note, the proposal does a couple of good things as well: It extends the 45Z tax credit from 2027 to 2034 in order to give the aviation industry a longer runway to build out the SAF economy; and it prohibits the importation of most foreign feedstocks — restricting the use of palm oil and other foreign crops that can contribute to international deforestation. Unfortunately, the good is outweighed by the bad.)
Why excluding ILUC is bad for the planet
FMR supports SAF policy that aligns with our guiding principles. But we strongly oppose the ILUC provision in the Klobuchar-Marshall bill for the following reasons:
It violates basic scientific principles
Branding something as “sustainable” without credible measurement undermines the scientific integrity of the SAF tax credit. Honesty is — and must be — the cost of doing business for this industry.
It undermines climate goals
By changing the rules for what counts as SAF, the Klobuchar-Marshall bill allows fuels that don’t reach the 50% carbon-reduction threshold to count toward climate goals — despite not actually meeting the standard.
It threatens water quality
By artificially making it easier for biofuel crops like corn to qualify, the proposal risks ushering in a worst-case scenario: SAF markets dominated by millions of new acres of summer annual row crops that are the primary source of pollution to the Mississippi River.
It impedes winter-hardy oilseeds
Winter-hardy oilseeds have a major competitive advantage over summer crops: They don’t cause indirect land use change. By assigning conventional crops a lower emissions score and higher tax credit than they deserve, this amendment neutralizes this competitive advantage and makes it much more difficult for alternative SAF feedstocks like winter-hardy oilseeds to compete. This is an unfair obstacle that will suppress investment in the most sustainable biofuel options.
It undermines public trust through greenwashing
The entire SAF enterprise only works if consumers, suppliers, governments and the airlines themselves can count on SAF policy delivering real climate solutions. Without that trust, the market is destined to fail. The Klobuchar-Marshall measure exposes the entire SAF tax credit to accusations of blatant greenwashing.
Looking ahead
Because this language is being considered through the federal budget reconciliation process, a simple majority in the U.S. House and Senate is enough for it to become law.
In the House, the ILUC language was included in the One Big Beautiful Bill Act, which passed by a vote of 215-214 on May 22.
The Senate has yet to assemble its reconciliation bill, but is expected to move over the summer. That’s why we’re asking FMR members and friends to reach out to our senators and ask them to reject the Klobuchar-Marshall ILUC provision.
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