Aemetis wins CPCFA backing for up to $1.1bn tax-exempt bond package

California's CPCFA has adopted an initial resolution supporting up to $1.1 billion of tax-exempt bonds for Aemetis dairy-digester, RNG, SAF and

By The Cleantech Times Editorial Team Tue, 9 June 2026

A modern building with reflective glass and textured stone facades stands under a clear, sunny sky, fronting a paved plaza with trees in planters and geometric concrete benches.

Aemetis (NASDAQ: AMTX) has secured a preliminary financing signal from California's Capital Programs & Climate Financing Authority (CPCFA), which has adopted an initial resolution supporting up to $1.1 billion of potential tax-exempt bond issuance for a suite of the company's projects. The resolution is an enabling step rather than a firm commitment — final bond issuance still requires completion of documentation and allocation from California's statewide tax-exempt bond volume cap — but it allows qualifying project costs incurred after the resolution date to be funded from any bonds eventually issued.

The projects covered span several stages of Aemetis's California development pipeline. At its existing biogas network in Keyes, the company intends to add more than 40 dairy digesters and extend its biogas collection pipeline, supplementing the 12 anaerobic digesters and 36-mile pipeline already in operation. Under the resolution, eligible costs also include an underground carbon-dioxide (CO2) sequestration project and a co-located sustainable aviation fuel (SAF) and renewable diesel (RD) production facility, both under development at Riverbank, California.

The deal

Tax-exempt bond financing — where interest paid to bondholders is exempt from federal income tax, typically allowing issuers to borrow at lower rates than conventional debt — is a structurally important tool for capital-intensive renewable-infrastructure projects. For Aemetis, which has been navigating tight margins in the California ethanol and RNG markets, cheaper long-duration capital could meaningfully change its project-level economics. Chief executive Eric McAfee said the lower interest cost relative to other financing sources had the potential to strengthen the company's balance sheet and support a path to profitability.

Aemetis currently operates its Keyes biogas-to-renewable natural gas (RNG) facility — which captures methane from dairy manure at more than 50 contracted dairies and delivers conditioned gas into the PG&E utility network — alongside a 65 million-gallon-per-year ethanol plant in California's Central Valley. The company also operates an 80 million-gallon-per-year biodiesel facility on India's east coast. The Riverbank SAF and sequestration projects are positioned to use CO2 and ethanol byproducts from the Keyes plant, creating a degree of vertical integration across the California operations.

Market context

California's low-carbon fuel standard (LCFS) and the federal renewable fuel standard (RFS) have historically provided the price floor that makes dairy-derived RNG economics viable, with LCFS credits for dairy biogas commanding some of the highest carbon intensities — and therefore the highest credit values — in the compliance market. SAF is a newer and less mature market; federal tax credits under the Inflation Reduction Act's 45Z clean fuels production credit are designed to stimulate US SAF capacity, and California's climate policy framework reinforces demand through aviation-sector commitments.

The CPCFA resolution also covers underground CO2 sequestration, which would qualify Aemetis projects for the 45Q federal tax credit — currently up to $85 per tonne for geologically stored CO2. Together, the three federal credit streams (45Z for SAF, 45Q for sequestration, and existing RFS credits for RNG) represent the incentive architecture underpinning Aemetis's California expansion plan. Investors should note, however, that the durability of the IRA tax-credit stack remains a legislative variable, and LCFS credit prices have been volatile.

The broader RNG-from-dairy sector has attracted growing infrastructure-fund interest in the United States, with several well-funded developers competing for contracted dairy supply. Competition for quality dairy offtake and state bond allocation could be constraints as Aemetis pursues its expansion. The company has not disclosed a construction timeline, a contracted SAF offtake price, or a sequestration storage partner — information that would materially affect the investment case for the bond programme.