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 test or operation of a Hermes 2 reactor itself (no reactor has operated at this site yet)
  • Not established in reviewed sources: NRC review or approval of the single-reactor, 50 MWe redesign
  1. Current stateDesign disclosed21 October 2025 · Company reported · Kairos Power (newsletter)

    Before: Not established in reviewed sources. Source: Kairos Power (newsletter) ↗

  2. Earlier statementTesting reported10 January 2024 · Company reported · Kairos Power

    Before: Not established in reviewed sources. Source: Kairos Power ↗

  3. Earlier statementDesign disclosed15 September 2023 · Regulator issued · U.S. Nuclear Regulatory Commission (Federal Register)

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

Evidence detail

Design disclosed

Redesign: one 50 MWe reactor in place of the original two-unit plant

A disclosed design is not a tested one.

“To accelerate our mission, we are enlarging Hermes 2 to a 50 MWe plant powered by a single commercial-scale reactor – a step change in scale from the smaller 14 MWe reactors envisioned in the original dual-unit plant concept.”
Attribution
Company reported
Publisher
Kairos Power (newsletter)
Dated
21 October 2025
First public disclosure
21 October 2025
State before
Not established in reviewed sources
Source read
11 November 2026

Inspect primary source: Kairos Power (newsletter) ↗

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