US producers of low-carbon fuels can start claiming the "45Z" tax credit providing up to $1/USG for road use and $1.75/USG for aviation, following the US Treasury Department's release today of proposed guidance for the credit.
The guidance includes proposed regulations and other tools to determine the eligibility of fuels for the 45Z tax credit, which was created by the Inflation Reduction Act to replace a suite of incentives for biofuels that expired at the end of last year. Biofuel producers have been clamoring for guidance from the US Treasury Department so they can start claiming the tax credit, which is available for fuels produced from 1 January 2025 through the end of 2027.
"This guidance will help put America on the cutting-edge of future innovation in aviation and renewable fuel while also lowering transportation costs for consumers," US deputy treasury secretary Wally Adeymo said. "Decarbonizing transportation and lowering costs is a win-win for America."
The creation of the 45Z tax credit has already prompted a change in US biofuels markets by shifting federal subsidies from blenders to producers. Because the value of tax credit increases for fuels with the lowest lifecycle greenhouse gas (GHG) emissions, it could encourage refiners to source more waste feedstocks such as used cooking oil, rather than conventional crop-based feedstocks.
While the guidance is still just a proposal, taxpayers are able to "immediately" use the guidance to claim the 45Z tax credit, until Treasury issues additional guidance, an administration official said.
The guidance on 45Z released today affirms that only the producer for the fuel is eligible to claim the credit, not blenders. To be eligible for the tax credit, the fuel must have a "practical or commercial fitness for use in a highway vehicle or aircraft" by itself or when blended into a mixture, Treasury said. Marine diesel and methanol suitable for highway or aircraft use are also eligible for 45Z, as is renewable natural gas that can be used as a transportation fuel.
Treasury also released an "annual emissions rate table" offering providers a methodology for determining the lifecycle GHG of fuel. Treasury said a key emissions model from the US Department of Energy, called 45ZCF-GREET, used to calculate the value of the 45Z tax credit is anticipated to be released today, although industry officials said it may be delayed until next week.
Treasury said it intends to propose regulations at "a future date" for calculating the GHG emissions benefits of "climate smart agriculture" practices for "cultivating domestic corn, soybeans, and sorghum as feedstocks" for fuel. Those regulations could lower the calculated lifecycle emissions of fuel from those crop-based feedstocks and increase the relative 45Z tax credit.
US biofuel producers said they are still awaiting key details on the 45Z tax credit, including the update to the GREET model. Among the outstanding questions is if the guidance released today provides "enough certainty to negotiate feedstock and fuel offtake agreements going forward", said the Clean Fuels America Alliance, an industry group that represents the biodiesel, renewable diesel and sustainable aviation fuel industries.
It is unclear how president-elect Donald Trump intends to approach this proposed approach for the 45Z credit, which will be subject to a 90-day public comment period. Trump has promised to "rescind all unspent funds" from the Inflation Reduction Act. But outright repealing 45Z would leave biofuels producers and farmers without a subsidy they say is needed to sustain growth, after the expiration last year of a $1/USG blender tax credit and a tax credit of up to $1.75/USG for sustainable aviation fuel. Biofuel and soybean groups were unsuccessful in a push last year to extend the expiring biofuel tax credits.
The 45Z credit is likely to be debated in Congress this year, as Republicans consider repealing parts of the Inflation Reduction Act. House Republicans have already asked for input on revisions to the 45Z credit, signaling they could modify the incentive. In a tightly divided Congress, farm-state lawmakers may hold enough leverage to ensure some type of biofuel incentive — and potentially one friendlier to agricultural producers than 45Z — survives.
