This project was initiated to provide new and updated definitions at section 1.48-9 of the Income Tax Regulations for energy property eligible for the energy credit under 26 U.S.C. 48. Due to statutory amendments, Treasury Regulation section 1.48-9 does not currently reflect 26 U.S.C. section 48. Public Law 117-169, 136 Stat. 1818 (August 6, 2022), commonly known as the "Inflation Reduction Act", made several changes to section 48. IRS issued Notice 2022-49 on October 5, 2022, requesting comments on changes made to section 48 by the IRA. We received several comments in response to this notice. We anticipate that the proposed regulations will also provide other rules applicable to energy property, such as rules for dual use property, application of the 80/20 Rule to retrofitted energy property, and eligibility of off-site components of energy property.