Executive Order 14301 set an ambitious goal for at least three test reactors to achieve criticality by July 4. Two private companies participating in the Department of Energy’s Reactor Pilot Program—Antares and Valar Atomics—reached this stage earlier in June, and Deployable Energy—participating in the DOE's Nuclear Energy Launch Pad—became the third last week.

In the last few weeks, reports indicated that Aalo would be next, reaching criticality at Idaho National Laboratory with a low-enriched uranium–fueled, sodium-cooled reactor on or near the target date set forth by President Trump’s EO 14301. In the early hours of July 4, Aalo’s critical test reactor—a full-scale zero-power version of its planned 10-MWe Aalo-X—did just that, becoming the fourth DOE-authorized reactor to hit the milestone.

On May 23, 2025, President Trump signed Executive Order 14301, “Reforming Nuclear Reactor Testing at the DOE,” which instructed the Department of Energy to create a Reactor Pilot Program (RPP)—a new system in which companies could pursue DOE authorization to build and test their first-of-a-kind nuclear technologies. EO 14301 set an ambitious goal for that program: three reactors achieving criticality by July 4, 2026.

Josh Freed

On top of the many celebrations planned for America’s 250th birthday, the Trump administration wants to mark a nuclear milestone as well: achieving criticality for at least three advanced reactor concepts by July 4, 2026.

But this wouldn’t really be a milestone. On a day of fireworks nationwide, it would just be more noise.

Third Way has celebrated the nuclear sector’s progress during the Trump administration and supported the goal of 400 GW of nuclear energy by 2050. Additionally, we think all five commissioners on the Nuclear Regulatory Commission have prioritized safety in new designs and defended an understaffed agency under pressure to bypass important processes.

Ahead of the July 4 deadline set by President Trump in Executive Order 14301, the nuclear community has been following the developments of the Department of Energy’s Reactor Pilot Program, in which companies have been pursuing DOE authorization to build and test their first-of-a-kind nuclear technologies. The EO set an ambitious goal of three reactors achieving criticality by July 4, 2026.

For just over a year, President Trump’s Executive Order 14301, “Reforming Nuclear Reactor Testing at the Department of Energy,” has loomed large because it pegged a stretch goal to a significant date: July 4, 2026. Will there be at least three participants in the Department of Energy’s Reactor Pilot Program whose reactors achieve criticality by Saturday’s deadline?

In June 2025, the Department of Energy announced the Reactor Pilot Program, an authorization pathway that allowed reactor developers to partner with the DOE to get first-of-a-kind (FOAK) reactors built and tested. Soon after, the DOE rolled out a complementary Fuel Line Pilot Program, which aimed to fast-track fuel projects. In all, 20 projects were accepted into the new programs.

Craig Piercy
cpiercy@ans.org

Recently, I spent an afternoon at Kairos Power’s Hermes construction site in Oak Ridge, Tenn. What I saw there was not a rendering, not a licensing presentation, not another panel about the future of advanced nuclear. I saw dozens of pilings built to NQA-1 standards. I saw seismic isolators ready for installation. I saw heavy equipment moving dirt and crews preparing concrete and steel.

I also saw a company doing genuinely innovative work with precast concrete techniques that could materially improve how we construct reactors in the future. None of it looked theoretical. It looked industrial.

On Thursday, Oklo announced that the Department of Energy’s Idaho Operations Office had approved the preliminary documented safety analysis (PDSA) for the company’s first deployment of its Aurora Powerhouse, which is currently under construction at Idaho National Laboratory.

It is the most recent in a long series of announcements from the 10 companies participating in the Reactor Pilot Program, which has a fast-approaching criticality deadline of July 4.

Leveraging more than $140 million in private capital fundraising, over 322,000 square feet of operational manufacturing space, and multifaceted partnerships with the Departments of Energy and Defense, reactor start-up Antares has become the first company involved in the Reactor Pilot Program to achieve zero-power fueled criticality—a full month ahead of the July 4 deadline set by President Trump’s Executive Order 14301.

This milestone, announced yesterday, was achieved with the company’s Mark-0, a forerunner to the R1, which is the company’s flagship design. The R1 is a sodium heat-pipe-cooled, TRISO-fueled microreactor. The Mark 0 is distinct from the R1 in that it is configured for zero-power criticality testing and as such is equipped with neither power conversion nor heat removal systems.

For Antares, this development represents a key validation of its reactor physics, control systems, and supply chain.

Washington, D.C. — Mark Peters, President of the American Nuclear Society (ANS), issued the following statement:

Oklo announced a new partnership with Los Alamos National Laboratory and Nvidia to perform AI-enabled research on nuclear infrastructure and fuel.

The partnership is focused on exploring plutonium-bearing fuels, including the development of science-based AI models to support fuel validation and materials science and fabrication research and development. The team will also be exploring the development of nuclear-powered AI computing centers at LANL.

Nuclear reactor designs approved by the Department of Energy or Department of Defense could get streamlined pathways through the Nuclear Regulatory Commission’s commercial licensing process should applicants wish to push the technology into the civilian sector.

A proposed rule introduced April 2 by the NRC would “improve NRC licensing review efficiency, where applicable, by explicitly establishing by regulation an additional means for reactor applicants to demonstrate the safety functions of their reactor designs, and thus, would contribute to the safe and secure use and deployment of civilian nuclear energy technologies.”

The American Nuclear Society recently hosted a panel discussion featuring prominent figures from the nuclear sector who discussed the industry’s ongoing push for criticality.

Yasir Arafat, chief technical officer of Aalo Atomics; Jordan Bramble, CEO of Antares Nuclear; and Rita Baranwal, chief nuclear officer of Radiant Industries, participated in the discussion and covered their recent progress in the Department of Energy’s Reactor Pilot Program. Nader Satvat, director of nuclear systems design at Kairos Power, gave an update on the company’s ongoing demonstration projects taking place outside of the landscape of DOE authorization.

On March 17, Oklo released a series of four press releases in the span of a few hours containing some of the first substantial updates the company has given on its various approval processes with the Department of Energy and Nuclear Regulatory Commission since January.

Specifically, Oklo announced that it has received two nuclear safety design agreement (NSDA) approvals from the DOE and a materials license from the NRC.

Attendees at last week’s 2026 Regulatory Information Conference, hosted by the Nuclear Regulatory Commission, saw extensive discussion of new reactor technologies, uprates, fusion, multiunit deployments, supply chain, and much more.

With the industry in a state of rapid evolution, there was much to discuss. Connected to all these topics was one central theme: the ongoing changes at the NRC. With massively shortened timelines, the ADVANCE Act and Executive Order 14300, and new interagency collaboration and authorization pathways in mind, speakers spent much of the RIC exploring what the road ahead looks like for the NRC.

Yasir Arafat, president and chief technology officer of Aalo Atomics, participated in the first day of sessions at the Nuclear Regulatory Commission’s annual Regulatory Information Conference (RIC). There, he recapped some of the company’s recent milestones and revealed new details on what lies ahead for Aalo.

His attendance at the event coincided with a number of announcements in the past two weeks. Those announcements covered new contracts with Global Nuclear Fuel and Baker Hughes, the release of a new strategic roadmap, the completion of fuel enrichment by Urenco USA, and a new approval from the Department of Energy.

The Department of Energy is set to expand on its Reactor Pilot Program and Fuel Line Pilot Program by introducing the Nuclear Energy Launch Pad, a DOE-led program to integrate the authorization, testing, and operation of reactors and fuel facilities from private nuclear developers. Furthermore, it will include two pathways—Launch Pad INL and Launch Pad USA—with options to access Idaho National Laboratory land or other sites around the nation.

The DOE plans to transition future pilot program applicants to the new Launch Pad model. Application requirements and review criteria will mirror those used in the reactor and fuel line pilot programs, and projects already in those programs will transition to Launch Pad with no need to reapply.

Two participants in the Department of Energy’s Reactor Pilot Program have recently announced significant milestones on their associated reactor projects. Aalo Atomics successfully completed its final design review (FDR), and Antares Nuclear has received DOE approval of its preliminary documented safety analysis (PDSA).

Thursday was a busy news day for the Nuclear Regulatory Commission, with three significant announcements.

In the span of a few hours, the NRC released the news of Ho Nieh’s promotion to chair, the reversal of the plan to sunset its aircraft impact assessment provisions, and new guidance for interagency collaboration.