This Notice of Proposed Rulemaking (NPRM) will provide guidance and address public comments regarding the implementation of 26 U.S.C. 45Z, including the calculation of emissions factors for transportation fuel, the determination of clean fuel production credits under 26 U.S.C. 45Z, and registration as a producer of clean fuel under 26 U.S.C. 4101 (as required by 26 U.S.C. 45Z(f)(1)(A)(i)(I)).

Notice 2025-10 (2025-6 I.R.B. 682), which is available at IRS.gov, contains draft intended rules for the 26 U.S.C. 45Z credit, rules for 26 U.S.C. 4101 registration under 26 U.S.C. 45Z, and requests public comments. Notice 2025-11 (2025-6 I.R.B. 704), which is available at IRS.gov, contains the emissions rate table, how to calculate emissions rates for the 26 U.S.C. 45Z credit, and requests public comments. These notices were published in early 2025 to meet the statutory deadline of January 1, 2025, however the rules need to be further formalized in an NPRM and then finalized.