Topic
Natrium
Start here: Natrium, explained: TerraPower's reactor with a built-in battery — NNN's reference piece on this topic.
TerraPower names Hyundai E&C as EPC for up to eight Natrium reactors
TerraPower named Hyundai E&C as EPC for up to eight Natrium reactors with completion, price and performance guarantees, plus an SK Innovation Korea term sheet.

TerraPower becomes first advanced reactor company to join INPO
TerraPower joined the Institute of Nuclear Power Operations on July 21, 2026 — the first advanced reactor company admitted, backing the 345-MWe Natrium build.
Every Nuclear Plant Under Construction in the US in 2026
The NNN tracker shows one U.S. nuclear unit under construction in 2026: TerraPower's 345 MW Natrium at Kemmerer, Wyoming, with a 2031 completion estimate.

TerraPower begins excavation at Kemmerer Unit 1
TerraPower says crews have begun excavation at Kemmerer Unit 1, moving the 345-megawatt Natrium reactor and storage system toward foundation work.

BWRX-300 vs AP300 vs Natrium: which SMR is actually winning?
BWRX-300 leads on deployment, AP300 banks on AP1000 heritage, Natrium adds storage. How the three highest-profile Western SMR programs compare in 2026.

Natrium, explained: TerraPower's reactor with a built-in battery
Natrium pairs a 345 MWe sodium-cooled fast reactor with molten-salt storage that boosts output to 500 MWe — and it's now under construction in Wyoming.
