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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: Final design status of the Xe-100 for this plant
  • Not established in reviewed sources: Any operating Xe-100 reactor anywhere
  1. Current stateDesign disclosed20 August 2026 · Regulator issued · U.S. Nuclear Regulatory Commission (Federal Register, via govinfo.gov)

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

  2. Earlier statementConflicting sourcesDesign disclosed4 June 2026 · Company reported · X-energy (SEC filing, Q1 2026 results presentation)

    Before: Not established in reviewed sources. Source: X-energy (SEC filing, Q1 2026 results presentation) ↗

  3. Earlier statementConflicting sourcesTesting reported4 June 2026 · Company reported · X-energy (SEC filing)

    Before: Not established in reviewed sources. Source: X-energy (SEC filing) ↗

  4. Earlier statementDesign disclosed14 May 2025 · 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 ↗

Evidence detail

Testing reported

Irradiation testing of TRISO-X pebble fuel (the Xe-100's fuel) at Idaho National Laboratory

Test results stay attributed to whoever reported them.

“In addition, irradiation testing for the TRISO-X pebble fuel is in progress at Idaho National Laboratory in collaboration with the NRC.”
Attribution
Company reported
Publisher
X-energy (SEC filing)
Dated
4 June 2026
First public disclosure
4 June 2026
State before
Not established in reviewed sources
Source read
11 November 2026

Inspect primary source: X-energy (SEC filing) ↗

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.

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