Click here for an archived PDF of the Q3 2026 email newsletter.
A note from our Chair
Meet the Fleet of Zero-Power Reactors TRTR Community, It’s been an amazing quarter to say the least. The U.S. Department of Energy (DOE) Reactor Pilot Program overshot its central regulatory target. Initiated under Executive Order 14301 to fast-track advanced nuclear tech, the program mandated that at least three advanced reactors achieve criticality by July 4, 2026. By utilizing a streamlined DOE Authorization Pathway that bypasses traditional multi-year NRC review, four privately developed microreactors successfully achieved zero-power fueled criticality by the deadline, and a fifth shortly thereafter. This marks the first time in over 40 years that new, non-light-water reactors have gone critical in the U.S.. Congratulations to the teams!
| Vendor | Reactor | Design | Criticality | Location |
| Antares | Mark-0 Microreactor | HALEU TRISO Fuel, Graphite Moderated, Sodium Heat Pipes | 6/04/2026 | INL |
| Valar Atomics | Ward 250 | HALEU TRISO Fuel HTGR He-Cooled | 6/18/2026 | San Rafael Energy Lab, UT |
| Deployable Energy | Unity Reactor | Standard LEU UO2-Fueled, H2O moderated, He Gas-Cooled | 6/30/2026 | INL |
| Aalo Atomics | Aalo-X Critical Test Reactor | UO2-Fueled Na-cooled, Graphite moderated | 7/04/2026 | INL |
| Oklo | Groves Isotope Test Reactor | Standard LEU UO2-Fueled, H2O-moderated and cooled, Open Pool | 8/05/2026 | Lockhart, TX |
Criticality is exciting, but as we experience every day in the operational research and test reactor world, criticality is only the first step to doing something more important with the reactor, whether that’s critical research, medical isotope production, commercial power and heat production, or educating the next generation essential to the success of the industry.
It is in this light that we should highlight the two concurrent breakthroughs of Kairos Power and TerraPower this spring and summer. Kairos Power broke ground on the nuclear site construction of the 50 MWe HERMES 2 at Oak Ridge TN. Kairos will supply power to a Google data center and Tennessee Valley Authority (TVA) through a Power Purchase Agreement (PPA). TerraPower officially began nuclear island construction on the 840MWt (345-500MWe) Natrium liquid sodium reactor in Kemmerer, WY. Both Kairos and TerraPower are ahead in the commercial deployment game with NRC-granted construction permits.
The NRC has a plethora of Title 10 regulation rulemakings in response to the ADVANCE Act and Executive Order 14300. Time is running out to participate in the critical public comment periods, many of which expire in the next week or two. The NRC responds to written public comments on the rulemakings, so don’t wait until NRC day at the annual conference!
This is the last quarterly newsletter before the 2026 annual conference on September 21-25 in Austin, TX. The NRC is bringing more than their usual complement, which this year is expected to include NRC Commissioner Matthew Marzano, the director for the Office of Nuclear Reactor Regulation (NRR) Anna Bradford and senior staff, and most of the Non-Power and Utilization Facilities (NPUF) branch. Registration is still open. See you there!
