TerraPower begins nuclear construction on the Natrium plant

TerraPower/Natrium (Kemmerer Unit 1)

On 23 April 2026 TerraPower officially began construction of Kemmerer Unit 1, with Bechtel moving into field execution, after receiving its NRC construction permit. The build is expected to take about five years.

• Kemmerer Unit 1 is a 345 MW sodium-cooled fast reactor with molten salt energy storage, enabling 500 MW peak output during demand spikes.
• Bechtel, the world's largest engineering and construction firm, is the engineering, procurement, and construction contractor with ~1,600 workers.
• Construction began 23 April 2026; the plant is expected to become the first utility-scale advanced nuclear plant operational in America.