Current state
| Status | Under construction |
| Design | Kairos KP-FHR (Hermes 2) (MSR, SMR) |
| Net capacity | 50 MWe |
| Country | United States |
| Vendor | Kairos Power |
| Owner / operator | Kairos Power |
| Construction start | 2026-04-17 |
| Original COD target | 2030 |
| Current COD estimate | 2030 |
| Schedule slippage | 0 years |
Notes
Power-unit capacity is up to 50 MWe at the plant level; NRC describes two 35 MWth low-power test reactors sharing a steam conversion system. Google reports operation scheduled for 2030. Site id omitted because no Oak Ridge site record exists in the entity registry.
Milestone log
- 2026-04-17 — Kairos Power broke ground on the Hermes 2 demonstration plant. (source)
The milestone log is append-only: corrections are recorded as new entries, never rewrites. Full history via /api/v1/changes.
Sources
- https://www.nrc.gov/facilities-safety/non-power-facilities/new-facility-licensing/hermes-2-kairos-application
- https://www.kairospower.com/updates/kairos-power-breaks-ground-on-hermes-2-demonstration-plant
- https://blog.google/company-news/outreach-and-initiatives/sustainability/google-first-advanced-nuclear-reactor-project-with-kairos-power-and-tennessee-valley-authority/