TerraPower breaks ground on Natrium — first non-light water reactor approved by NRC

TerraPower began construction on the Natrium reactor in Kemmerer, Wyoming on April 23, 2026. The sodium-cooled fast reactor (345 MWe base, 500 MWe peak) uses an integrated molten salt thermal energy storage system. It is the first commercial reactor construction permit in approximately a decade.

23 April 2026