As human factors specialists working at the intersection of human performance and nuclear operations, we are witnessing one of the nuclear sector’s most significant transitions in decades. The emergence of small modular reactors, microreactors, and other advanced designs is reshaping the industry’s landscape. Digital instrumentation and controls, passive safety systems, and increased automation are creating opportunities for greater safety margins and more flexible operation. These same features also fundamentally redefine what it means to “operate” a nuclear plant. Interactions among human roles, automation, and passive systems shape how people maintain awareness, exercise judgment, and intervene when necessary. These developments affect both operational realities and the regulatory foundations on which nuclear safety is built.

The remote, automatic, real-time adjustment of a research reactor’s power by a geographically distributed control system has been reported by researchers from Idaho National Laboratory, the Grainger College of Engineering at the University of Illinois–Urbana-Champaign, and Purdue University. The investigators first used an automatic adjustment “digital control loop” system to demonstrate remote adjustments of Purdue’s PUR-1 research reactor. They then applied a reinforcement learning model that simulates the interaction of physical forces inside the reactor, making the loop system more autonomous.

Summer at the American Nuclear Society carries with it a sense of renewed momentum as the incoming president takes office and starts making plans for the year ahead. This has been particularly true in the last few years, as nuclear energy moves into a new era marked by broader public interest, stronger policy support, and a growing sense of possibility across the field. Mark Peters, the Society’s 72nd president, shares that optimism—and he is focused on turning it into results.

The quest of the Department of Energy’s Office of Environmental Management to find a private-sector partner to design, build, and operate a commercial-scale facility to recycle defense-related used fuel at Idaho National Laboratory has transitioned to the review and selection phase, the DOE said July 7. Responses to a request for applications were due on June 19.

Over the past two weeks, in the “Trivia Tuesday” and “Throwback Thursday” sections of Nuclear News Daily, we have dug into the story of Idaho National Laboratory’s official list of reactors, past and present, at the site. We are now bringing that exploration to Newswire, compiling the research done for the Daily and extending the conversation further.

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.

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.

In 2019, a familiar landmark at Idaho National Laboratory was scheduled for demolition. Though striking for both its physical presence and its significance to nuclear history, the containment dome that once housed Experimental Breeder Reactor-II sat unused—that is, until INL realized its potential as a reactor testing facility.

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.

The final executive session of the American Nuclear Society’s 2026 Annual Conference was titled “With Great Processing Power Comes Great Responsibility: Ethics and Opportunities for AI and Tomorrow’s Workforce.”

On June 1 at the American Nuclear Society’s Annual Conference in Denver, Colo., a team from Idaho National Laboratory presented a session titled “Lessons Learned from MARVEL Reactor Fabrication.” The presentation highlighted challenges that arose as they moved from design to manufacturing and assembly, with a focus on reactor part fabrication, Stirling engine implementation, and reactivity control system development.

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.

Two companies specializing in ultrasonic nondestructive testing and structural health monitoring are to advance to the final phase of a selection process to demonstrate acoustic emission technologies for the automated monitoring of spent nuclear fuel dry storage canisters.

On Tuesday, during Mark Peters’s last days as the American Nuclear Society’s vice president/president-elect before assuming the presidency on June 4, he sat down with ANS CEO Craig Piercy for a Fireside Chat at the Annual Conference.

The MITRE CEO weighed in on his career path, what excites and worries him about the resurgence of nuclear energy, and juggling work-life balance with his new duties as ANS’s 72nd president.

“It’s going to be a lot of fun. It’s an important year,” he told Piercy.

On Tuesday, the National Reactor Innovation Center hosted an industry day for the Nuclear Energy Launch Pad, providing a forum for companies to learn more about how the program works, timelines, collaboration with the various entities involved, and available resources.

The launch pad is a long-term program stemming from the Reactor Pilot Program and Fuel Line Pilot Program. It aims to fast-track regulatory processes for new reactors and fuel facilities that meet certain milestones.

Earlier this week, Idaho National Laboratory announced that its Structural Properties Laboratory (SPL) has been fully operational since January. Located at INL’s Materials and Fuels Complex, the SPL houses the lab’s first new hot cell in 50 years.

Utah State University and Battelle Energy Alliance, an Idaho National Laboratory contractor, have signed a memorandum of understanding, committing to a Strategic Understanding for Premier Education and Research (SUPER) agreement, which formalizes and expands the university’s collaboration with INL.

Clean Core Thorium Energy has announced the completion of its nearly two-year ANEEL fuel irradiation testing and qualification campaign at Idaho National Laboratory.

The idea behind ANEEL (Advanced Nuclear Energy for Enriched Life) fuel is to provide existing pressurized heavy water reactors with a fuel option that has increased high-burnup performance without requiring any modification to the reactors.

The Department of Energy’s Office of Environmental Management has announced that its Idaho Cleanup Project (ICP) recently received department approval for the conceptual design for a spent nuclear fuel staging facility project at Idaho National Laboratory.