Post Page Advertisement [Top]

Alternative Fuels

Is Ethanol-to-Jet the Next Big Greenwash? SAF Mandates and the Ethanol Lobby's New Frontier.

 

Introduction

On July 4, 2025 — Independence Day — President Donald Trump signed a sweeping legislative package known as the "One Big Beautiful Bill" into law. The bill dismantled a significant portion of Biden's clean energy agenda: gutting solar subsidies, clawing back electric vehicle credits, and shrinking support for wind power. The message was clear — fossil fuels first, green energy second.

Except for one industry.

Buried inside the same bill that tore apart the clean energy economy was a lavish, bipartisan carve-out worth an estimated $25.7 billion in taxpayer dollars for a fuel nobody would dare call fossil — because it comes from a farm. While solar panels lost their subsidies, corn ethanol was quietly handed the keys to America's aviation sector.

The vehicle for this transfer: a tax credit for Sustainable Aviation Fuel (SAF). The mechanism: making corn ethanol eligible for that credit, despite overwhelming scientific evidence that it neither meets the required emissions benchmarks nor deserves the "sustainable" label. The lobby that made it happen: the same agricultural and ethanol industry machine that has operated in Washington for five decades.

Welcome to Ethanol-to-Jet — the fossil fuel lobby's strategy in green clothing, the ethanol industry's lifeline as road use evaporates, and the newest chapter in one of the oldest stories in American politics.




1. The Context: Why the Ethanol Industry Needed a New Market

To understand the ETJ push, you must first understand the ethanol industry's existential predicament.

For decades, the U.S. ethanol sector has been built almost entirely on one product: corn-based fuel blended into petrol for road vehicles. As of 2025, the United States produces approximately 15 billion gallons of ethanol per year, the vast majority from corn and the majority of that blended into gasoline.

That market is now structurally threatened.

The rapid proliferation of electric vehicles is eroding gasoline demand. The U.S. Energy Information Administration and most credible forecasters project that road-use ethanol demand will plateau and then contract as EV adoption accelerates through the late 2020s and 2030s. For an industry that has built 200+ plants, invested tens of billions in infrastructure, and maintained political relationships across two dozen corn-producing states, this is not a theoretical problem. It is an existential one.

The industry's response has been characteristically aggressive: find a new mandated market before the old one disappears.

Aviation is the obvious target. Agricultural interests are increasingly worried that electric vehicles will crush demand for corn ethanol and soy biodiesel on the road and have been furiously lobbying Washington to create new demand in the sky. And aviation is uniquely vulnerable to this lobbying because it is genuinely, authentically difficult to decarbonize — making any alternative to jet fuel look attractive to regulators and airlines desperate to meet net-zero pledges.

The strategic move is elegant: position ethanol as a solution to aviation's hardest problem, secure government mandates and tax credits, and watch a new captive market replace the fading road-use one. It is the same playbook that built the road-use ethanol empire in the 1980s, 1990s, and 2000s. The only thing that has changed is the application — and the altitude.


2. What Is Ethanol-to-Jet, and Does It Actually Work?

Ethanol-to-Jet (ETJ) — also called Alcohol-to-Jet (ATJ) — is a two-stage process. First, ethanol is produced from a biomass feedstock (corn, sugarcane, sugar beets, or cellulosic waste). Second, that ethanol is chemically converted into jet fuel through a process involving dehydration, oligomerization, and hydrogenation.

The process is technically real and commercially demonstrated. In 2024, LanzaJet commissioned the world's first commercial-scale ETJ facility — the Freedom Pines Fuels plant in Soperton, Georgia — with a capacity of 10 million gallons per year. Other companies actively pursuing ETJ projects include Gevo, Summit Next Gen, and SAFFiRE Renewables. In February 2025, Gevo and Axens announced a partnership to accelerate ETJ deployment further.

ETJ is relatively new at commercial scale. Questions remain about the carbon intensity of SAF produced via ETJ, and the market signals for longer-term expansion of ETJ production capacity remain unclear.

The technical pathway is sound. The economics are viable — particularly when government subsidies are available. The problem, and it is a fundamental one, is the carbon math.

The Emissions Problem

The central claim that justifies SAF policy — and the tax credits and mandates that flow from it — is that SAF dramatically reduces lifecycle greenhouse gas emissions compared to conventional jet fuel. The IRA's SAF tax credit offers emissions-reduction guidance: it starts at $1.25 per gallon for SAF that reduces lifecycle greenhouse gas emissions by at least 50% compared to conventional jet fuel, increasing by an additional 1 cent per gallon for each percentage point of emissions reductions beyond this threshold.

The critical question is whether corn-based ETJ actually meets this 50 percent reduction bar.

The answer, based on independent lifecycle analysis, is: it depends enormously on what you count — and who is doing the counting.

Conventional corn grain-derived ETJ fuel reduces greenhouse gas emissions by approximately 22 percent compared to fossil jet fuel under standard lifecycle accounting. Potential reductions of 26 to 96 percent are possible when incorporating renewable energy sources, with a 6 to 32 percent increase in production costs.

Let that sink in. The baseline case — corn ethanol converted to jet fuel using conventional energy inputs — achieves only a 22 percent emissions reduction against petroleum jet fuel. The SAF tax credit requires 50 percent. Corn-based ETJ, as currently produced, does not qualify on its own merits. It only gets there with added carbon capture, renewable energy inputs, or — critically — by gaming the accounting rules.

The conventional Alcohol-to-Jet process, which converts ethanol into aviation fuel with a yield of roughly 90 percent, reduces carbon intensity by only 4.5 to 20 percent compared to kerosene under certain assessments. Advanced approaches using CO₂ capture — gas fermentation and Fischer-Tropsch synthesis — can achieve reductions of 84 to 90 percent, but at dramatically higher cost and complexity.

The Land Use Accounting Trick

Here is where the politics becomes decisive — and dishonest.

The reason corn ethanol can only claim modest emissions reductions is that a proper lifecycle assessment includes Indirect Land Use Change (ILUC): the emissions generated when additional land is converted to farming to replace food or feed crops displaced by biofuel production. When forest is cleared in Brazil to grow soybeans to replace American soybeans diverted to biofuels, those deforestation emissions belong in the corn ethanol's carbon ledger.

ILUC emissions for corn ethanol can add 20 to 25 grams of CO₂ equivalent per megajoule to the fuel's carbon intensity score. Remove ILUC from the calculation, and corn ethanol looks significantly cleaner. Include it, and it fails the 50 percent threshold.

This is precisely why the "One Big Beautiful Bill" made one of its most consequential moves in the fine print: one of the most significant changes to 45Z within H.R. 1 is a provision excluding emissions associated with indirect land use change (ILUC) from a fuel's carbon intensity score. Ignoring ILUC can decrease CI scores of certain land-intensive conventional biofuels like corn ethanol and soy biodiesel by ignoring up to 20–25 g CO₂e/MJ, yielding higher per-gallon tax credits for these fuels.

In a particularly egregious policy twist, the legislation would ban any consideration of those land-use emissions when calculating which fuels are sustainable. That would be like banning consideration of smokestack emissions when calculating which power plants are sustainable.

The European Union has taken the opposite position. The EU SAF mandate under the ReFuelEU program excludes corn-based ETJ, because food- and feed-based fuels do not qualify. That limits the opportunity for US producers of corn-based ETJ to expand into foreign markets.

This divergence is not a technical dispute. It is a political one. The EU, facing less direct pressure from a corn lobby, applied the science. The U.S., facing enormous corn-state political pressure, rewrote the science.


3. The Scale Fallacy: Can ETJ Actually Decarbonize Aviation?

Proponents of ETJ point to the U.S.'s massive existing ethanol infrastructure — 15 billion gallons per year — as proof of scalability. They have a point on the supply side. The ethanol industry can, in theory, redirect a portion of its output toward jet fuel conversion.

The problem is the demand side, and the land that feeds it.

1.7 gallons of corn ethanol are needed to make 1 gallon of sustainable aviation fuel. If the U.S. were to reach its stated goal of 35 billion gallons of SAF using ethanol — which is currently its leading approach — this would require 114 million acres of corn. That's 20% more than the total area currently planted with corn in the United States for all purposes.

Read that again. Meeting the U.S.'s own SAF targets using corn ethanol would require planting corn on an area larger than the entire current U.S. corn crop. The math is not aspirational. It is impossible — and it would have catastrophic consequences for food prices, water resources, and biodiversity long before it approached meaningful scale.

An analysis by the American Enterprise Institute concluded that producing about 10 percent of U.S. jet fuel from SAF by 2030 — an explicit Biden Administration goal — would require about half the U.S. soybean crop, occupying enough farmland to cover the state of Nebraska. Princeton senior research scholar Tim Searchinger has calculated that using vegetable oils like soybean for one fourth of global aviation fuel would require 40 percent of global cropland, an area twice the size of India.

These are not fringe calculations. They come from mainstream research institutions whose work is peer-reviewed and publicly available. The ethanol lobby is perfectly aware of them. They simply have no political incentive to acknowledge them.

What the EU Chose Instead

The contrast with European policy is instructive. The ReFuelEU Aviation Regulation mandates that the minimum SAF blend to be supplied at EU airports starts at 2% of overall fuel supplied in 2025, increasing incrementally to 70% by 2050. It also includes specific sub-targets for the most environmentally friendly synthetic e-fuels (power-to-liquid SAF), requiring 1.2% e-SAF within the overall 6% blending target by 2030. Crucially, the EU mandate explicitly excludes food-based crop fuels.

The EU's approach directs aviation's decarbonization effort toward genuinely advanced pathways: waste-based HEFA, synthetic e-fuels made from green hydrogen and captured CO₂, and cellulosic second-generation biofuels. These are more expensive in the short term. They do not benefit a politically powerful domestic crop lobby. That is precisely why the U.S. is not choosing them.


4. The Money: A $25.7 Billion Transfer in Plain Sight

The One Big Beautiful Bill: A Case Study in Captured Legislation

The legislative history of SAF policy in the United States is as instructive as the science — and considerably less ambiguous.

The Inflation Reduction Act of 2022 created the Section 40B tax credit for SAF and later folded it into the broader 45Z Clean Fuel Production Credit, offering up to $1.75 per gallon for SAF that achieves the highest carbon intensity reductions. The explicit intent was to incentivize genuinely low-carbon aviation fuels.

The ethanol lobby immediately recognized this as an opportunity — and began working to ensure that corn ethanol could qualify. Following what was described as "an intense lobbying campaign," the Treasury Department issued guidance allowing the use of an alternative emissions accounting model (GREET) that treated corn ethanol more favorably than the CORSIA model used internationally.

Then came the "One Big Beautiful Bill."

The Joint Committee on Taxation estimated that the expansion and extension of 45Z will cost taxpayers $25.7 billion over the next decade. The credit is projected to reduce federal payments to the Treasury by $10.5 billion in FY2029 alone, which surpasses the combined annual cost of the old $6 billion ethanol tax credit and the $3 billion biomass-based diesel tax credit, which Congress let expire in 2011 and 2024, respectively.

In other words, the ethanol industry has not merely replaced its old subsidy. It has created a new one that is larger than all its previous subsidies combined — dressed in the language of aviation sustainability.

Corn ethanol and soy-based biodiesel — already mandated under the Renewable Fuel Standard and subsidized since the Carter era — could once again dominate the biofuels subsidy stream. The OBBBA (One Big Beautiful Bill Act) also preserves a carveout that eliminates penalties for converting forests or grasslands into farmland for biofuels production, effectively weakening the definition of "clean" fuel and significantly broadening eligibility for the credit.

A bill marketed as a bold fiscal discipline measure has thus created the most lavish ethanol subsidy in U.S. history — one that could cost more in a single year than the entire historic annual ethanol credit it replaced.

The Bipartisan Shame

While the overall bill has no Democratic supporters, and even some Republicans have objected to its assault on other energy subsidies, the biofuels carve-out has strong backing from farm-friendly Democrats, who created the original tax credit for SAFs in the Inflation Reduction Act of 2022. There's always been broad bipartisan support for the federal mandate requiring corn ethanol to be blended into gasoline, and even though the overall "Big Beautiful Bill" aims to dismantle Biden's climate policies and extend Trump's tax cuts, its biofuels language was lifted from a bipartisan "Farm to Fly" bill explicitly designed to get ethanol to qualify for SAF credits of up to $1.75 a gallon.

Dan Lashof, a climate scientist and senior fellow at the World Resources Institute, described it plainly: "It's shocking but it's not surprising. Agriculture has an extremely well-oiled lobbying machine."

The Farm to Fly Act — the bipartisan bill that seeded the SAF credit provisions — was explicitly designed to bridge Republican and Democratic support for corn ethanol's aviation expansion. Its genius lies in its framing: rural Republican representatives can tout American energy independence and farm income support; urban Democratic representatives can point to climate action and decarbonization of a notoriously dirty sector. Neither group needs to discuss, publicly, what the scientific evidence says about whether corn jet fuel actually reduces emissions.


5. What Genuine SAF Looks Like — and Why It's Being Crowded Out

There is a profound irony at the heart of the ETJ controversy: the subsidies designed to promote low-carbon aviation fuel are being captured by the feedstock that produces the least climate benefit, crowding out the genuinely promising alternatives.

HEFA: The Proven Workhorse

Most SAF produced in the United States comes from the hydroprocessed esters and fatty acids (HEFA) pathway. HEFA uses vegetable oils, waste fats, and waste oils as inputs and relies on the same basic equipment used to make renewable diesel — a fuel already produced at commercial scale. Plants producing SAF with HEFA face lower capital costs than other technological pathways.

Today, only 0.3 percent of the world's aviation fuel is classified as sustainable, and the overwhelming majority of that is recycled cooking oil processed via HEFA — a feedstock that is genuinely low-carbon because it does not require additional farmland. United Airlines has an ad campaign touting its commitment to making SAF from waste instead of crop-grown feedstock, featuring Oscar the Grouch as its "Chief Trash Officer."

The problem with waste-based HEFA is supply: there is simply not enough used cooking oil and waste fat in the world to power even a fraction of global aviation at scale. The availability of waste cooking oil and lipids past 2030 is in question, especially as HEFA competes with biodiesel for used cooking oil and other waste inputs.

Power-to-Liquid: The Real Future

The genuine long-term answer to aviation decarbonization is Power-to-Liquid (PtL) or e-SAF — synthetic jet fuel made from green hydrogen (produced with renewable electricity) combined with captured CO₂. Fischer-Tropsch PtL could reduce carbon intensity by up to 90 percent, while gas fermentation achieved reductions of around 84 percent compared to conventional jet fuel, far exceeding the 50 percent threshold required for tax credit eligibility.

The EU recognizes this: its ReFuelEU mandate includes explicit sub-targets for e-SAF precisely because these fuels represent the only pathway to near-zero-carbon aviation at genuine scale. The DOE estimates that the U.S. has around 350 million dry tons of currently available but unused biomass — agricultural and forestry waste — that could serve as feedstock for truly advanced SAF without competing with food production.

Environmental groups note that less intensive approaches for making SAF include using biomass waste, such as sawdust from lumber mills, branches and bark collected during forest-thinning, and the corn stalks and leaves left over after harvest. Very little, if any, SAF is made today using these feedstocks, though there's plenty of opportunity.

The reason these advanced pathways are not receiving the dominant share of subsidies is straightforward: they do not benefit the corn and soy lobby, they are more expensive in the near term, and they do not have fifty years of political infrastructure backing them in Washington.

The Crowding-Out Effect

The alterations included in the OBBBA — while positive for those that produce first-generation renewable fuels from corn and soybeans — could end up significantly constraining the market potential for SAF altogether.

Here is the mechanism. By lowering the per-gallon credit for SAF (from a maximum of $1.75 to $1.00 per gallon) while simultaneously making it easier for conventional corn ethanol to qualify for the same credit, the OBBBA directs subsidy money toward the least innovative, least climate-effective feedstock, while advanced SAF producers — who need higher per-gallon support to cover their genuinely higher production costs — face a more hostile economics.

Even with the previous $1.75 tax credit, alcohol-to-jet SAF costs $1.24 per gallon more than fossil jet fuel; with the $0.75 reduction in the credit, the gap widens to $1.99. Without meaningful policy support, advanced ETJ from waste feedstocks or PtL e-SAF simply cannot compete commercially.

The bill that claimed to promote sustainable aviation fuel has, in practice, made it harder for genuinely sustainable aviation fuel to survive economically, while handing the largest benefit to the industry with the longest lobbying arm and the lowest climate credentials.


6. The Airlines' Uncomfortable Complicity

The aviation industry's role in this controversy deserves its own examination, because airlines have simultaneously committed publicly to sustainability and lobbied for policies that undermine it.

The International Air Transport Association defines sustainable aviation fuels as those that reduce CO2 emissions by up to 80% compared to conventional jet fuel and are made from feedstocks that "do not compete with food crops or output, nor require incremental resource usage such as water or land clearing."

By that definition — IATA's own definition — corn-based ETJ is not sustainable aviation fuel. It competes directly with food crop production. It requires significant additional land. And under full lifecycle accounting including ILUC, it does not achieve 80 percent emissions reduction.

Yet major U.S. airlines supported the ethanol industry's push for corn-based ETJ to qualify for SAF credits despite previously agreeing that SAF production should not compete with food production.

The reason is economic. Corn ethanol, at scale, is the most affordable SAF-adjacent feedstock available today. Waste-based and advanced SAFs are more expensive. Airlines operating on thin margins and under intense price competition have no incentive to pay more for fuel — unless mandates require it or competitors are similarly constrained. In the absence of strict carbon accounting, they will always choose the cheapest option that allows them to label their fuel "sustainable" in their marketing.

Little of that nuance is reflected in ads or promotional materials about SAF, which is why more skeptical observers say they are concerned that greenwashing is taking hold within the aviation industry. "Airlines at this point are treating anything that is not petroleum jet fuel as sustainable," said one climate scientist from WRI.

Concerns over greenwashing have already led to a class-action lawsuit against Delta Airlines questioning the effectiveness of their emissions offset program. More such lawsuits may follow as the gap between what airlines claim and what the science supports becomes increasingly visible.

In Europe, this risk is being addressed directly by law. The EU's 2024 Directive Empowering Consumers for the Green Transition, which applies from September 2026 onwards, aims to tackle unfair commercial practices that deceive consumers. Environmental claims such as commercial communications regarding "SAF" will be subjected to the new amendments, requiring clear, relevant, and reliable information. Airlines caught making unsupported "sustainable" fuel claims in the EU may face regulatory action under consumer protection law.

The United States has no equivalent incoming regulation. In its absence, the greenwashing will continue and likely accelerate.


7. The Global Fault Lines: US vs. EU vs. Rest of World

The ETJ controversy has exposed a profound and deepening divergence in how different jurisdictions are approaching aviation decarbonization.

United States: Corn-based ETJ is being made eligible for SAF credits through the OBBBA, with ILUC excluded from carbon intensity calculations and $25.7 billion in taxpayer support over the next decade flowing primarily to conventional agricultural biofuels. The U.S. produces about 15 billion gallons of ethanol per year, mostly from corn and mostly blended into gasoline. Future adoption of electric vehicles could cause the market for ethanol used in gasoline blending to plateau or shrink — driving the industry's pivot toward aviation.

European Union: The ReFuelEU Aviation Regulation mandates a minimum SAF blend starting at 2% in 2025, increasing to 70% by 2050, with explicit sub-targets for e-SAF and exclusion of food-crop-based biofuels. The EU is betting on advanced pathways, accepting higher short-term costs in exchange for genuinely transformative long-term decarbonization.

The Conflict: Limiting the opportunity for US producers of corn-based ETJ to expand into foreign markets, the EU SAF mandate under ReFuelEU excludes corn-based ETJ, because food- and feed-based fuels do not qualify. This creates a direct trade and market access conflict: American corn ethanol producers building ETJ capacity will find their product shut out of the EU market — the world's most demanding aviation regulatory environment.

This divergence matters for consumers and policymakers globally, because it means that "SAF" does not mean the same thing on both sides of the Atlantic. A passenger flying on a United Airlines flight fueled with corn-based ETJ and one flying on a Lufthansa flight fueled with waste-based HEFA are both being told they are flying sustainably — but the environmental reality is completely different.




8. The Verdict: Greenwash, or Genuine Bridge?

Is Ethanol-to-Jet the next big greenwash? The answer, as with most energy policy questions, is nuanced — but the preponderance of evidence leans heavily toward yes, at least in the form that the ethanol lobby is promoting.

The legitimate case for ETJ:

  • It is commercially viable and technologically demonstrated at scale.
  • Cellulosic ETJ — using corn stover, agricultural residues, or purpose-grown energy crops rather than food-grade corn — can achieve genuinely significant emissions reductions of 70 percent or more.
  • It leverages existing ethanol infrastructure, potentially reducing transition costs.
  • In a world where perfect is the enemy of good, an imperfect 22 percent reduction is better than zero.
  • With CCS added, corn stover-derived ETJ can achieve negative emissions, with minimum fuel selling price increases of only 1 to 22 percent — making it a potentially viable climate tool.

The greenwash case:

  • The ETJ being subsidized today is primarily corn grain-based, not cellulosic, delivering only 4.5–22 percent emissions reduction — well below what the science requires.
  • The OBBBA deliberately excludes ILUC from carbon accounting to make corn ethanol look cleaner than it is — a manipulation of scientific standards for political convenience.
  • The $25.7 billion in taxpayer support is flowing to an industry that already receives RFS mandates, crop insurance subsidies, and decades of accumulated public investment.
  • The scale mathematics are incoherent: meeting U.S. SAF targets with corn would require more farmland than currently exists for all corn, with catastrophic food security implications.
  • The EU — the world's most sophisticated clean energy regulator — explicitly excludes corn ETJ on environmental grounds.
  • The subsidy architecture crowds out genuinely advanced, lower-carbon pathways by reducing available credits and creating a price floor that disadvantages innovation.
  • Airlines are using "SAF" marketing to claim sustainability benefits that the science does not support.

The pattern is identical to the road-use ethanol playbook: mandate the product, subsidize the production, exclude inconvenient emissions from the accounting, and market it as green while collecting the revenue.

The only difference is that this time, the altitude is higher — and so is the greenwash.


Conclusion: What Genuine Aviation Decarbonization Requires

Aviation is a genuinely difficult sector to decarbonize, and the urgency is real. Worldwide, aviation accounts for 2% of all carbon dioxide and 12% of all CO₂ from transportation. ICAO's Carbon Offsetting and Reduction Scheme for International Aviation caps net CO₂ from aviation at 2020 levels through 2035.

The sector needs solutions. But the solutions it gets will be determined less by what the science recommends than by who lobbies hardest.

What genuine aviation decarbonization would look like:

Scientifically rigorous carbon accounting — including ILUC — for all fuels claiming SAF status. No exceptions for politically convenient feedstocks.

A hierarchy of feedstocks: waste-based HEFA first, cellulosic second-generation biofuels second, and food-crop-based biofuels last — with sharply declining support as you descend the hierarchy.

Dedicated advanced SAF investment: the $25.7 billion being directed toward corn ethanol via 45Z would fund approximately 15 large-scale commercial PtL or cellulosic SAF plants. That would create genuinely new industry rather than subsidizing one that has been on public support for fifty years.

Transparent airline marketing standards: requiring airlines to disclose the specific feedstock and lifecycle emissions of SAF they purchase, not just "sustainable aviation fuel" as a generic claim.

Mandatory flex-fuel adoption timelines: for aircraft manufacturers and airports, with binding blending obligations tied to genuinely verified emissions reductions.

The ethanol industry's pivot to aviation is politically inevitable. An industry with 200 plants, hundreds of thousands of rural jobs, and fifty years of bipartisan political relationships does not quietly accept the decline of its market. It finds a new one and brings its lobbying infrastructure to bear.

The question for policymakers, consumers, journalists, and investors is whether they will allow the same political economy that produced road-use ethanol's mixed environmental record to be transplanted wholesale into aviation's decarbonization story — or whether, this time, the science will be allowed to lead.

The early evidence from the "One Big Beautiful Bill" is not encouraging.


This article draws on publicly available legislative texts, Congressional Budget Office and Joint Committee on Taxation estimates, peer-reviewed lifecycle assessment literature, independent research from WRI, RFF, ICCT, and Clean Air Task Force, and reporting from Yale E360, Canary Media, and Climate Home News. All figures are sourced and verifiable.


Read More Topics:

No comments:

Post a Comment

Please do not enter any spam link in the comment box

Bottom Ad [Post Page]