Under ConstructionMicroreactor
Radiant Kaleidos Demonstration Unit in INL DOME
📍 IDDeveloper: Radiant Industries
Capacity
1 MW
Expected Operation
—
Reactor Type
Radiant Kaleidos
Regulatory Status
DOE approved PDSA Feb 2026; first fuel tranche received 2026-07-01; reactor left El Segundo, CA for the INL DOME on 2026-08-12. Five-phase test program (zero-power criticality through 150-hour full-power run) was targeted for Q3 2026; no criticality announcement found as of 2026-10-10.
Details
Primary Use
Demonstration / research
Research detail · verified 2026-10-10
Stage
Under construction
Commercial power
No (test, research, military or demonstration)
Stated target operation
Test campaign targeted to conclude in Q3 2026 (Radiant, per NEI Magazine 2026-08-21) — not met per available sources
Key dates
2025-08-12 selected for DOE Reactor Pilot Program; 2026-02 PDSA approved; 2026-07-01 first fuel tranche received; 2026-08-12 shipped to INL DOME; 2026-09-17 passive cooldown test completed (Radiant)
Workforce
Radiant building R-50 reactor factory on an 80-acre Oak Ridge, TN site (factory, not a reactor site). Radiant also selected for Buckley SFB (Air Force ANPI) and Fort Benning (Army Janus) — separate rows.
Not verified / conflicts
radiantnuclear.com returned 403. Criticality status after mid-Sept 2026 unconfirmed; one search summary said no criticality announcement as of end of Q3 2026. Passive cooldown test (2026-09-17) from Radiant newswire release found in search; full text not opened.
Sources
- https://www.ans.org/news/article-8178/the-deadline-arrives-checking-in-on-the-reactor-pilot-program/
- https://www.neimagazine.com/news/kaleidos-moves-to-idaho-test-facility/
- https://world-nuclear-news.org/articles/deployable-energy-to-test-its-unity-nuclear-battery-in-dome
- https://www.energy.gov/node/4852259
- https://www.newswire.com/view/content/radiant-successfully-completes-passive-cooldown-test-for-kaleidos-22444092
State Policy Context
View nuclear-related legislation and energy stats for Idaho