In a May 2024 letter from Terra Power to the NRC:
This letter provides clarifying information on the relationship and agreements between US SFR Owner, LLC (USO), a wholly owned subsidiary of TerraPower, LLC (TerraPower), and TerraPower as it pertains to the Construction Permit Application (CPA) for Kemmerer Power Station Unit 1 (hereafter referred to as Kemmerer Unit 1).
By letter dated March 28, 2024, the CPA was submitted by TerraPower, on behalf of USO, to construct a nuclear-powered generating plant designated as Kemmerer Unit 1 (ADAMS Accession Number ML24088A059). USO is the applicant for the CPA. While TerraPower is the direct and controlling owner of USO, TerraPower is not the applicant.
USO is a special purpose entity that was created on July 7, 2020, to serve as a vehicle for TerraPower’s U.S. Department of Energy (DOE) Advanced Reactor Demonstration Program (ARDP) bid for the Natrium™ Demonstration Project (1).
(1) a TerraPower and GE-Hitachi technology.
See more here: https://www.nrc.gov/docs/ML2412/ML24123A242.pdf
Also archived here: https://wyomingnuclearactivity.info/wp-content/uploads/2025/11/TerraPower-USO-NRC_ML24123A242.pdf
The Construction Permit for US SFR Owner, LLC is for the “Energy Island” component of the Natrium Project. This permit included an exemption via provisions from President Trump Executive Order (#1) Ordering the Reform of the Nuclear Regulatory Commission , May 23, 2025.
Documents/Articles on US SFR Owner:
Japan and TerraPower expand SFR development partnership to support carbon neutrality efforts
Mar 28, 2024 NRC: TerraPower, LLC — Kemmerer Power Station Unit 1 Application
May 2024 Letter from Terra Power to NRC regarding subsidiary US SFR Owner, LLC
May 12, 2025: TerraPower’s bid to start energy island construction gets EA/FONSI
May 15, 2025: US SFR Owner, LLC; Kemmerer Power Station, Unit 1; Exemption
June 20, 2025: 90 FR 26333 – US SFR Owner, LLC; Kemmerer Power Station, Unit 1; Draft Environmental Impact Statement
“Submit comments on the draft EIS by August 4, 2025”
July 9, 2025: Nuclear Regulatory Commission to Expedite Review of TerraPower Reactor Project
Oct 21, 2025: Environmental Impact Statement for the Construction Permit Application for Kemmerer Power Station Unit 1 – Final Report (NUREG-2268)