Aemetis monetises $18m in Section 45Z clean fuel tax credits

The NASDAQ-listed biofuels producer received $14.5m net cash from selling 45Z credits tied to ethanol and renewable natural gas output across 2025 and

By Rowen Brooks Sun, 6 September 2026 AI level 2 of 5

AI level 2 of 5: drafted by our AI editorial assistant from source material our editor chose; fact-checked, edited and signed off by Mark Walker, Editorial Director. What the levels mean

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Aemetis (NASDAQ: AMTX) has completed two further sales of Section 45Z Clean Fuel Production Tax Credits, bringing in a combined $18 million of gross credit value and approximately $14.5 million in net cash proceeds after transaction costs. The Cupertino, California-based company describes the sales as its second and third 45Z transactions in six months, signalling that tax-credit monetisation has become a routine cash-flow lever rather than a one-off event.

The credits break down into a $6 million tranche generated by 2025 ethanol production and $12 million from year-to-date 2026 ethanol and renewable natural gas (RNG) output. The 2026 credits were valued at approximately $0.33 per ethanol gallon and $15.20 per MMBtu (million British thermal units) of RNG. Aemetis operates a 65-million-gallon-per-year ethanol plant in California's Central Valley and a dairy-waste biogas-to-RNG network in the same state.

The 45Z mechanism

Section 45Z is a production tax credit introduced under US climate legislation that rewards low-carbon fuel producers on a sliding scale tied to the carbon intensity of each gallon or unit of energy produced. The credit rate is calculated using the 45ZCF-GREET model, a joint Department of Energy and Department of Agriculture emissions-intensity tool updated most recently on 12 June 2026. Because the credit is transferable, producers such as Aemetis can sell credits to tax-equity buyers rather than carry them against their own tax liability, converting the incentive directly into operating cash.

Eric McAfee, chairman and chief executive of Aemetis, said the transactions "illustrate the value of Section 45Z Clean Fuel Production Tax Credits as a recurring contribution to cash flow." He flagged two pending model updates that the company expects to lift credit values further: a Department of Agriculture low-carbon feedstock calculator for corn ethanol, and a revised dairy-specific RNG emissions rate that would separate dairy-derived biogas from other animal-waste streams. McAfee added that Aemetis "urges Treasury and the DOE to maintain the integrity and purpose of Section 45Z" as agencies continue to implement rules under legislation passed four years ago and updated by the One Big Beautiful Bill (OBBB) in July 2025.

Market context and policy read-across

The transferability of production tax credits under the Inflation Reduction Act and its successors has created a nascent tax-credit transfer market in which biofuel and RNG producers, clean-hydrogen developers and other qualifying manufacturers sell credits to corporate buyers with tax appetite. For smaller, capital-constrained producers like Aemetis, this mechanism can be material: the $14.5 million net cash receipt represents real liquidity against a project base that includes an India-based biodiesel plant, a California carbon-sequestration development and a planned sustainable aviation fuel (SAF) facility, as well as the existing ethanol and RNG operations.

The broader biofuels sector is watching the 45Z rulemaking closely. Corn ethanol's eligibility and credit rate depend heavily on how the GREET model accounts for feedstock emissions, making the pending USDA calculator update a commercial, not merely technical, matter. Similarly, dairy RNG producers argue that separating dairy-cow methane from other animal-waste streams reflects genuinely lower lifecycle emissions and should yield higher credit values. Both updates remain subject to agency discretion and could be contested.

Aemetis's use of 45Z proceeds to fund production expansion connects the tax-credit mechanism directly to capacity growth, suggesting the company views the credit not just as a balance-sheet item but as project-finance capital for its next phase. Investors will watch for the agency model updates McAfee flagged, additional 2026 credit-sale announcements, and progress on the planned SAF and CO2 sequestration projects as the next milestones.