State

Design disclosed

A disclosed design is not a tested one.

Open question

What has the technology itself been shown to do, at what scale and under what conditions?

  • Not established in reviewed sources: Any operation or integrated test of the reactor or storage system
  • Not established in reviewed sources: Storage energy capacity in MWh
  1. Current stateDesign disclosedDate not disclosed · Government record · U.S. Department of Energy, Office of Nuclear Energy

    Before: Not established in reviewed sources. Source: U.S. Department of Energy, Office of Nuclear Energy ↗

  2. Earlier statementDesign disclosed23 October 2025 · Regulator issued · U.S. Nuclear Regulatory Commission (Federal Register)

    Before: Not established in reviewed sources. Source: U.S. Nuclear Regulatory Commission (Federal Register) ↗

  3. Earlier statementDesign disclosed29 March 2024 · Company reported · TerraPower

    Before: Not established in reviewed sources. Source: TerraPower ↗

Evidence detail

Design disclosed

Plant design as described in the NRC final environmental impact statement notice

A disclosed design is not a tested one.

“The proposed facilities would house one 840-megawatt thermal, pool-type, sodium-cooled fast reactor connected to a molten salt energy storage system that enables variable energy supply up to 500 megawatts electric net.”
Attribution
Regulator issued
Publisher
U.S. Nuclear Regulatory Commission (Federal Register)
Dated
23 October 2025
First public disclosure
23 October 2025
State before
Not established in reviewed sources
Source read
11 November 2026

Inspect primary source: U.S. Nuclear Regulatory Commission (Federal Register) ↗

What this does and does not establish

An exact passage match shows the source says this. It does not prove the underlying claim is true.

Watch technical milestonesInspect project history

Natrium Kemmerer Unit 1: ledger · Power Inflection