The U.S. Nuclear Regulatory Commission (NRC) has announced it will accelerate its review of TerraPower’s construction permit application for the Kemmerer Power Station Unit 1, aiming to complete the process by 31st December 2025 – six months ahead of the previous schedule. The expedited timeline is attributed to “frequent and productive engagements” with TerraPower and recent federal efforts to streamline nuclear permitting, including President Donald Trump’s May 2025 Executive Order on nuclear regulatory reform.
TerraPower, through its subsidiary US SFR Owner, submitted the application in March 2024 to build a sodium-cooled, advanced Natrium reactor near an existing coal-fired plant in Kemmerer, Wyoming. The NRC emphasised that meeting the new schedule depends on TerraPower’s continued responsiveness in resolving outstanding technical issues, particularly concerning materials, design components, and seismic and structural systems.
The Natrium technology, developed by TerraPower and GE Hitachi, features a 345 MWe sodium-cooled fast reactor paired with a molten salt-based energy storage system. This storage allows the plant to boost output to 500 MWe for over five and a half hours, offering greater flexibility to support renewable-heavy grids. Construction on non-nuclear portions of the Kemmerer facility, such as the molten salt energy storage system, is already underway following an NRC exemption granted in May.
The NRC’s schedule acceleration coincides with the public comment period on the draft environmental impact statement (EIS) for the Kemmerer project, which assesses public health impacts and currently supports permit issuance barring new safety concerns. The public can submit comments until 4th August.
The Kemmerer project is backed by the Department of Energy’s Advanced Reactor Demonstration Program, with a target completion date of 2030. If successful, it will be the first commercial advanced reactor of its kind in the U.S., a significant milestone as most sodium-cooled fast reactors currently operate only in Russia, and similar Western projects have faced decades of delays or cancellations.
