The 45Z Clean Fuel Production Credit, Explained for Corn and Soybean Farmers

Start with what it is — and what it isn't

The 45Z Clean Fuel Production Credit is a federal tax credit paid to companies that produce clean transportation fuel in the United States — ethanol plants, renewable diesel and biodiesel refiners, and sustainable aviation fuel producers. The lower the lifecycle carbon intensity of the fuel they make, the larger the credit per gallon.

Read that again, because the most important thing to understand about 45Z is who gets the check: the fuel producer, not the farmer. There is no form you file, no payment that lands in your account because you no-tilled a field. If someone tells you 45Z pays farmers directly, they've got it wrong.

So why should you care? Because the feedstock — your corn, your soybeans — makes up a big share of that fuel's carbon intensity. Research consistently puts feedstock production at somewhere between 40% and 60% of a biofuel's total lifecycle CI. The plant can't hit a low CI number, and can't capture the bigger credit, unless the grain coming in the door was grown in a lower-carbon way. That gives producers a real, dollars-and-cents reason to pay more for low-CI bushels. That premium — the part that flows back to you — is the whole opportunity.

Where 45Z stands in 2026

A few facts worth pinning down, because this is a fast-moving area and a lot of what's floating around is out of date:

The credit runs on fuel produced and sold from the start of 2025 through the end of 2029. The One Big Beautiful Bill Act extended it two years beyond its original 2027 sunset, which matters — it means the demand signal isn't a one-season blip you can safely ignore.

The same law tightened feedstock sourcing: to qualify, fuel generally has to be made by U.S. producers from feedstock grown in North America — the United States, Mexico, or Canada. For a Midwest corn or soybean grower, that's a tailwind. It narrows the field of eligible grain to, essentially, us.

The rules are still being written. Treasury and the IRS put out proposed regulations in early 2026, with a public comment window that ran into the spring. The carbon-accounting model the whole thing runs on — the Department of Energy's 45ZCF-GREET model — was released in early 2025, and USDA's companion Feedstock Carbon Intensity Calculator (FD-CIC), the piece that credits practices like no-till, cover crops, and nutrient management, is still in beta and not expected to be finalized until later in 2026.

I'll be straight with you about what that last point means in practice.

The honest part: the farmer premium is real, but still early

Here is the thing the glossy presentations skip. The vision — you adopt conservation practices, your grain earns a measurably lower CI score, and that translates cleanly into a higher price at the elevator — is not yet a smooth, everywhere-you-look market. In a lot of the country it's still closer to theory than to a posted bid. The plumbing that connects your practices to a verified CI number to a check is being built right now, and it's uneven.

That doesn't make it fake. Programs are live in pockets, the ethanol and renewable-diesel industries are actively lining up low-CI supply, and the finalized calculator will pour concrete under a lot of what's currently handshake. But if you go into this expecting every buyer within thirty miles to hand you fifteen cents a bushel for cover crops tomorrow, you'll be disappointed, and disappointment is how good opportunities get written off too early.

The right posture, I think, is the one we take with basis or a new hybrid: pay attention early, get your own numbers in order, and be ready to move the moment the premium shows up in your area — because the growers who already know their CI and can prove their practices will be first in line, and they'll capture it before it gets bid away.

What actually moves your feedstock CI

Your feedstock carbon intensity — the farm-stage piece, measured per bushel — comes down to a handful of levers, and none of them are exotic:

Nitrogen is almost always the single biggest one. It's the fertilizer's manufacturing footprint plus the nitrous oxide that comes off the field after you apply it. Rate and source both matter.

Tillage and cover crops move soil carbon. No-till and reduced tillage keep carbon in the ground; a cover crop pulls more down. Both push your CI lower.

Fuel, manure, and yield fill out the rest. Diesel burned per acre adds to it; manure and higher yields spread the same footprint across more bushels, which lowers CI per bushel.

The full walkthrough of how each lever moves the number — and how much — is its own piece: How to Lower Your Corn's Carbon Intensity (and Why It's Worth Money Under 45Z). The short version is that most of what lowers CI is stuff good operators are already doing or already considering. 45Z just, for the first time, attaches a price to it.

One more distinction that trips people up

You'll see a "corn CI of 29" quoted around 45Z. That number is in grams of CO₂-equivalent per megajoule of fuel — it's the finished ethanol's carbon intensity, the number the plant lives and dies by. It is not the same as your feedstock CI, which is measured per bushel of grain and covers just the farming stage.

Both matter, and they're linked — your per-bushel feedstock number is one of the biggest inputs into the plant's per-megajoule fuel number — but don't let anyone hand you a single figure without telling you which one it is. When Clevis estimates your CI, it's the farm-stage, per-bushel number, structured to line up with USDA's FD-CIC. It's a decision-support estimate to gauge your readiness and opportunity — not a certified CI or tax figure. The official CI that a credit is actually based on gets determined by the fuel producer and the verification process.

What to do this season

You don't need to wait for the final rules to get ahead of this. Three moves, in order:

First, know your number. You can't market something you can't measure. Get an estimate of the feedstock CI on each of your corn and soybean fields, and see which fields are already sitting low and which are dragging.

Second, keep the records. The practices that lower CI only count if you can document them — tillage, cover crops, nitrogen rate and source, manure. The growers who capture the premium first will be the ones who can prove what they did without scrambling for it a year later.

Third, ask your buyers the direct question: Do you run a low-CI or climate-smart premium, what CI baseline do you use, and what documentation do you need? Even a "not yet" tells you where your local market is, and puts you on the list for when it changes.

Clevis was built to make all three of those the easy path. Our Carbon Intelligence tool estimates the feedstock CI on every one of your fields from the tillage, nitrogen, cover crop, and yield data already in your account — no re-entry — shows you what a low-CI premium could be worth at nearby buyers, and produces an audit-ready practice record you can hand to a plant. You can see it under Carbon & 45Z inside Clevis.

45Z didn't reward the way you farm before. It's starting to now. The farmers who'll get paid for it are the ones who can show their number when the buyer finally asks.