For months, one of the biggest open questions in the US biofuels market has been how farm-level carbon reductions would translate into 45Z credit value. The USDA's final Regenerative Feedstock Rule brings that answer closer.
The rule creates a voluntary framework linking regenerative agricultural practices to biofuel feedstock markets for corn, soybeans, sorghum, and spring canola. It also introduces the USDA Feedstock Carbon Intensity Calculator, or FD-CIC, which quantifies feedstock carbon intensity in grams of CO₂ equivalent per bushel.
The significance is not just technical; it is commercial.
Under 45Z, the value of the clean fuel production credit depends on the finished fuel's lifecycle carbon intensity. That makes lower-carbon feedstocks more than a sustainability claim. They become a potential pricing signal, procurement advantage, and margin lever for ethanol, renewable diesel, biodiesel, and SAF producers.
Many US growers already use practices that can reduce field-level emissions or improve soil health. The USDA says 68% of corn farmers and 70% of soybean farmers already implement at least one regenerative practice. The new rule gives producers and supply chain participants a clearer structure for documenting those practices and connecting them to biofuel markets.
The FD-CIC currently covers several crops:
Field Corn
Soybeans
Sorghum
Spring Canola
It allows producers to evaluate nutrient management, no-till, reduced tillage, cover crops, nitrification inhibitors, and manure nitrogen.
That matters because the market has been waiting for a bridge between agronomic practice and credit calculation. Without a recognized way to quantify feedstock CI, biofuel producers face uncertainty when estimating 45Z value, evaluating supply contracts, or comparing domestic feedstock options.
The rule also outlines standards for field-level CI quantification, mass-balance chain-of-custody, traceability, record-keeping, auditing, verification, and regenerative agriculture practices.
This shifts the conversation from "Which feedstock is cheapest?" to "Which feedstock can be documented, verified, and valued?"
For producers, that creates both opportunity and complexity. A lower-CI feedstock may improve credit economics. However, this only happens if the supporting data can move through the supply chain with enough integrity to support tax credit claims. Procurement teams, originators, aggregators, and fuel producers will need to understand not only the crop but also the documentation behind it.
The rule could also intensify competition for qualifying domestic feedstocks. If regenerative corn, soybeans, sorghum, or canola can support stronger 45Z economics, buyers may begin to segment feedstock markets by documented CI profile rather than treating crop inputs as interchangeable commodities.
That could influence basis levels, contracting structures, and regional sourcing strategies. It may also create new premiums for growers able to provide verified low-CI feedstocks into biofuel supply chains.
However, the value will not be uniform. CI outcomes can vary depending on multiple factors:
Geography
Yield
Farming Practices
Fertilizer Usage
Documentation Pathways
The winners will be the companies that can translate policy language into procurement decisions before the market fully prices in the change.
The USDA rule is a major step, but it is not the end of the 45Z implementation story. The FD-CIC must ultimately work within the broader 45ZCF-GREET and Treasury/IRS credit framework.
The DOE released the 45ZCF-GREET model in January 2025, and IRS guidance describes 45Z as a credit for domestically produced clean transportation fuel sold during the eligible credit window.
Related: DOE’s Updated 45Z GREET Model Brings Clarity to US Biofuels Markets
For market participants, the key questions now include:
How quickly will buyers incorporate FD-CIC results into feedstock procurement?
Will verified regenerative feedstocks command meaningful premiums?
How will mass balance and documentation requirements affect smaller growers and aggregators?
Which regions and crop pathways will show the strongest CI advantage?
How will 45Z economics interact with RINs, LCFS, SAF demand, and global feedstock trade?
The USDA's final Regenerative Feedstock Rule reinforces a broader shift underway in the biofuels market. Carbon intensity is no longer just a compliance metric applied at the fuel production stage. It is becoming a supply chain strategy that begins at the field level.
For biofuel producers, feedstock buyers, traders, and investors, the implication is clear. Policy value will increasingly depend on upstream visibility. As 45Z moves from regulation to implementation, companies will need timely insight into feedstock availability, CI scoring, trade flows, policy shifts, and margin impacts.
Prima CarbonZero helps market participants connect these signals across the biofuels and low-carbon feedstocks value chain. The platform gives teams the intelligence they need to make better decisions in a more carbon-sensitive market.
Want to learn even more about where the market is headed and what to expect in the coming months? Check out our latest on-demand webinar, Q3 Biofuels Outlook: Iran War Implications, for an expert-led breakdown of the most critical topics across the biofuels market.