In Washington, more than a year after the IRA was passed, the Biden administration has yet to decide on the methodology or methodologies that may be used to determine which SAFs meet the required 50% reduction in greenhouse gas (GHG) emissions over their life cycle and can thus receive financial support. The International Council on Clean Transportation says the supply chain LCA emissions estimated in GREET and CORSIA are closely aligned. But emissions from indirect land-use changes (ILUC) and soil organic carbon credits from land-management practices differ widely due to assumptions in the underlying models. These indirect emissions cannot be easily verified by regulators like the Treasury Department or easily demonstrated by producers, and thus there is the risk that using GREET would widely diverge from the CORSIA approach and existing U.S. fuel policies. Adopting GREET as a “similar” LCA methodology for SAFs in the IRA could incentivize fuel pathways with uncertain GHG reduction benefits, said the ICCT.
