Antares Nuclear
🇺🇸 Torrance, US · Founded 2023 · Active
Antares Nuclear is a company in Torrance, California, founded in 2023, that designs small transportable fission reactors for defence, space and remote uses. Its main design, the R1, is a microreactor of 100 kWe to 1 MWe with TRISO coated-particle fuel in a graphite core and sodium heat pipes that carry heat away passively. In June 2026 its Mark-0, a zero-power test version of the R1 with no power-generating equipment, reached criticality at Idaho National Laboratory under the Department of Energy's Reactor Pilot Program; ANS Nuclear Newswire reported it as the first company in that programme to do so and said it had raised more than $140 million. Antares says it aims to produce electricity in 2027.
- Sector
- Fission
- Technology
- Heat-pipe microreactor
- Fuel
- TRISO particle fuel
- Role
- Reactor developer
Terms
- Heat-pipe microreactor
- Heat moved by sealed heat pipes rather than pumped coolant or forced convection. No primary pumps and no coolant loop, which suits very small transportable reactors. Heat-pipe describes how heat is moved, not the neutron spectrum. Moderator and fuel vary by design: some designs are fast and unmoderated, others use a graphite or beryllium oxide moderator, with TRISO or metal fuel, usually HALEU.
- TRISO particle fuel
- Fuel kernels about the size of a poppy seed, each wrapped in layers of carbon and silicon carbide, so every particle acts as a tiny containment for its own fission products. The US Department of Energy reports that irradiated particles came through more than 300 hours of testing at temperatures up to 1,800 °C with no to minimal damage. That record covers the particle designs, temperatures and burnups actually tested; a claim outside that envelope is not covered by it.
Designs
| Design | Developer | Approach | Electrical output per unit | Size class | Licensing stage |
|---|---|---|---|---|---|
| R1 Microreactor Antares R1 | Antares Nuclear | Heat-pipe microreactor | 0.1 to 1 MWe planned | Microreactor | No milestone recorded |
People
- Jordan BrambleCEO & Co-Founder · founder
- Rian BahranChief Nuclear Officer
- Mark MassieChief Engineer