Kairos Power
UC Berkeley spinout developing the KP-FHR fluoride-salt-cooled high-temperature reactor; Google's commercial advanced-reactor partner
Alameda, CA~600Founded 2016~$700M private + ~$303M DOE (cost-share) raisedPrivate (no recent disclosed valuation) valuationkairospower.com
SectorsNuclear
Google Master Agreement
Up to 500 MW / 6-7 plants by 2035
Oct 2024; first hyperscaler advanced-reactor PPA in the industry
Hermes NRC Construction Permit
First non-LWR CP since 1968
Dec 2023; ends 55-year drought of non-light-water reactor construction permits in the US
KP-FHR Output
140 MWe per module
FLiBe-cooled, TRISO-fuel pebble-bed; 650 C outlet enables industrial heat applications
DOE ARDP Cost-share
Up to $303M
ARDP Risk-Reduction award (Sep 2020); funds Hermes through commissioning
Funding History
Total raised: ~$700M private + ~$303M DOE (cost-share) · Latest valuation: Private (no recent disclosed valuation)
| Round | Date | Amount | Valuation | Key Investors |
|---|---|---|---|---|
| Founder + Early | 2016-2020 | Undisclosed | — | Mike Laufer / Per Peterson / Ed Blandford (founders) |
| DOE ARDP Risk-Reduction | Sep 2020 | Up to $303M (DOE cost-share) | — | US Department of Energy (Advanced Reactor Demonstration Program) |
| Series B / Strategic | Sep 2022 | $303M (private) | — | Cohort sources include Sun Hung KaiHercules CapitalMaterial Impact |
| Strategic Round | 2024 | Undisclosed | — | Tokyo Electric Power (TEPCO)MitsubishiReported per Nikkei + others |
Product Specifications
| System | Type | Status |
|---|---|---|
| KP-FHR | Fluoride-salt-cooled high-temperature reactor (140 MWe per module, TRISO fuel pebbles) | Design certification work; first commercial ~2030 |
| Hermes | 35 MWth non-electricity demonstration reactor (Oak Ridge, TN) | Under construction; commissioning ~2027 |
| Hermes 2 | 2-pack electricity-producing demonstration (28 MWe net) | NRC CP application submitted Apr 2025 |
| ETU (Engineering Test Unit) | Non-nuclear FLiBe-salt integrated test loop (Albuquerque) | Operating since 2022 |
| FLiBe Salt Production | Vertically integrated salt manufacturing | Production-scale facility online (Q3 2025) |
Partnerships & Investors
GoogleCustomer / Master Developer
Oct 2024 Master Plant Development Agreement for up to 500 MW across 6-7 KP-FHR plants by 2035; first hyperscaler advanced-reactor PPA in the industry.
Tennessee Valley Authority (TVA)Strategic / Host
Host utility for Hermes + Hermes 2 at Oak Ridge; potential operator of future commercial KP-FHR fleet.
US Department of EnergyCost-share Sponsor
ARDP Risk-Reduction award: up to $303M through ~2027 for Hermes.
Oak Ridge National LaboratoryResearch
Materials, fuel-cycle, and salt-chemistry research collaboration; FLiBe production lineage.
Materion + Materials Sciences CorpStrategic / Supply
FLiBe salt component supply chain; vertically integrated through Kairos's own production facility.
Westinghouse + Curtiss-WrightSupply Chain
Reactor pressure vessel + components for Hermes.
Key Milestones
2016
Company Founded
Mike Laufer (CEO, ex-Westinghouse), Per Peterson (UC Berkeley), Ed Blandford spin Kairos out of the UC Berkeley nuclear engineering program
Sep 2020
DOE ARDP Risk-Reduction Selection
Up to $303M in cost-share over 7 years for the Hermes demonstration; one of 5 risk-reduction awardees
Sep 2022
ETU (Engineering Test Unit) Testing Begins
Non-nuclear integrated test loop at Albuquerque NM site; validates pumps, instrumentation, and fluoride-salt chemistry
Dec 2023
Hermes NRC Construction Permit
First non-light-water reactor NRC construction permit since 1968; landmark licensing milestone
Jul 2024
Hermes Construction Start
Groundbreaking at Oak Ridge, TN site adjacent to TVA assets; targeted commissioning ~2027
Oct 2024
Google Master Plant Development Agreement
Up to 500 MW across 6-7 KP-FHR plants by 2035; first hyperscaler PPA for any advanced reactor design
Apr 2025
Hermes 2 CP Application
Construction permit for Hermes 2 (electricity-producing 2-pack) submitted; targets ~2028 commissioning at Oak Ridge
Q3 2025
Salt Production Facility Online
FLiBe (fluoride-salt) production at scale begins; resolves a key fuel-cycle bottleneck for KP-FHR deployment
2030 (target)
First Commercial KP-FHR for Google
First commercial 140 MWe plant under the Google PPA; site under selection