Idaho National Laboratory Unveils DOME Microreactor Facility at INL Ahead of America’s 250th Anniversary
ARCO, Idaho — The Idaho National Laboratory has unveiled a new facility designed to advance the future of nuclear energy in the United States, with the first reactor experiment slated to power up on July 4th — a milestone timed to coincide with America’s 250th birthday celebration.
The facility, housed inside the historic EBR-2 containment building at INL in Eastern Idaho, is known as DOME — an acronym for Demonstration of Microreactor Experiments. The unveiling marks a significant chapter in Idaho’s long history as a global leader in nuclear research and innovation.
A Facility Built to Withstand the Extreme
Curtis Nielsen, Technical Program Manager for the National Reactor Innovation Center, described the engineering behind the DOME facility as purpose-built for safety and resilience. The structure features thick, air-sealed, lockable doors designed to prevent radiation exposure during reactor operation and to ensure complete containment under any circumstances.
“It’s completely safe. It’s a contained facility. It’s designed to take major earthquakes, natural disasters, and still contain everything that’s inside of it to never leave the facility,” Nielsen said in remarks reported by Idaho News 6.
The sealed access design also serves a critical operational function. “When the reactor is in operation, you don’t want people to go in there and expose themselves to radiation,” Nielsen explained. “So it’s designed to lock, close, and have a very tight seal so that people don’t get in and air doesn’t come out.”
Nielsen indicated that the facility is equipped to host rotating reactor experiments from a variety of companies and research partners. Each reactor will remain at the INL site for approximately one year before being removed, with plans to bring in one new reactor annually for the next two decades.
“The first one, we are getting prepped. In fact, all the equipment you see right here is to help us get set up for that first reactor, and that’s going to be this summer,” Nielsen said. The target activation date for the first microreactor is July 4, 2026 — a date Nielsen called “another reason to celebrate on America’s 250th birthday.”
Idaho’s Nuclear Legacy — From EBR-1 to the Next 20 Years
Idaho’s connection to nuclear energy stretches back more than seven decades. EBR-1, the world’s first nuclear power plant, was built in 1951 just outside Arco, Idaho. The historic facility now operates as a public museum and is scheduled to reopen as a free attraction on Memorial Day, offering visitors a look at the origins of commercial nuclear power.
INL has operated for 75 years across its world-class research campuses in Eastern Idaho, advancing innovations in nuclear energy, renewable energy, and national security solutions. The DOME facility represents the laboratory’s latest effort to position the United States at the forefront of advanced nuclear development.
According to Nielsen, the work being done at DOME is fostering a renaissance in advanced nuclear experimentation not seen since the 1950s. “What it does is — it allows us to go bring in different companies’ reactor experiments, small reactors that could be used in small communities as disaster relief or for impoverished areas,” he said.
Nielsen expressed clear pride in what the facility means for Idaho and for the nation. “To me, it’s one of those things that Idaho should be proud of that we have this kind of facility in our state, and we’re on the leading edge of development of these advanced reactors in a time when these reactors are proving out how safe they are,” Nielsen told Idaho News 6.
The DOME project reflects growing national momentum behind small modular and microreactor technology as policymakers and energy producers seek reliable, domestic energy production options. For more on statewide energy and economic developments, visit Idaho News for the latest coverage across the Gem State.
What Comes Next
With the first microreactor experiment scheduled to go live on July 4th, INL officials are finalizing preparations inside the DOME facility this summer. The EBR-1 Atomic Museum near Arco is set to open to the public on Memorial Day as a free attraction, giving residents and visitors a chance to connect Idaho’s nuclear past with its future. INL’s 20-year experiment schedule — one reactor per year — positions Eastern Idaho as a national hub for microreactor research for decades to come. Residents and energy observers across Bonneville County and the broader region will be watching closely as INL marks this historic milestone.