Promoting a new nuclear age to power the AI boom with next-generation reactors remains feasible, but it’s the U.S. military and NASA that are stepping in to accelerate the development of even smaller nuclear reactors – called microreactors – to power remote bases, revolutionize combat and fuel deep space exploration.
As the data center boom slows a bit and nuclear hype subsides – stock valuations are falling and planned IPOs are canceled – the federal government is increasing funding to support the implementation of microreactors on domestic military bases by 2028. Tentative plans are to eventually extend their reach to remote bases in harsh weather conditions – potentially near combat zones – and eventually to lunar bases and the far reaches of the solar system.
In June, nuclear startup Antares successfully fired up its Mark-0 microreactor, the first to cross the finish line in the race for the Trump administration’s pilot program to get the next generation of reactors to reach criticality.
Next, Antares aims to install its 1-megawatt R1 reactor at the U.S. Army’s Fort Bragg in North Carolina by September 2028. Even more ambitious, founder and CEO Jordan Bramble aims to install an R1-S (the S stands for “space”) on the moon as early as 2030. In September, the Department of Defense awarded Antares $161 million to develop an R1-S reactor integrated into the spacecraft for flight certification. Solar power and radioisotopes are considered the short-term energy solution on the Moon, with nuclear microreactors considered the permanent solution.
“We will need fission power on the far side of the Moon,” Bramble said. Fortune. “Fission will be our best way to do really high-powered things in orbit. If we’re going to send landers to Europa, Enceladus and Triton (moons of Jupiter, Saturn and Neptune) and try to find microbial life under the ice, we’ll probably need fission power to do that.”
The idea is to provide agile and reliable baseload energy that is clean, fusion-resistant, and relatively agile for limited energy uses. Of course, the technology still needs to be commercially proven in the field and not just in testing labs. Historically, the only comparable uses have been within the Navy – for decades – for nuclear-powered submarines and aircraft carriers to avoid constant refueling. “We always believed from the beginning that (the Department of Defense) would be the first to adopt advanced nuclear energy,” Bramble said. “It’s obvious at this point.”
In the short term, the U.S. military is working with Antares, Radiant, General Atomics and others to install microreactors on its larger Lower 48 bases to prove their reliability and protect critical defense infrastructure from any grid outages. This is Project Janus, which announced $2.2 billion in rewards in August.
The largest recipient of the Janus Awards is microreactor startup Radiant, which specializes in a transportable one-megawatt reactor, enough to power about 750 homes, that only takes up the space of “three parking spaces.”
But Radiant has designs for its 1-megawatt Kaleidos system extending well beyond the Lower 48 and its first projects at Fort Benning in Georgia and Buckley Space Force Base in Colorado, said Tori Shivanandan, chief operating officer and president.
“The United States has struggled, not just in major conflicts, to support troop deployments internationally,” Shivanandan said. Fortune. “If you’re moving your troops and you want defense systems to protect those troops when they’re deployed overseas, you also need to make sure you have the power to defend your troops. »
This year’s war in Iran has shown that US military bases in the Middle East – and beyond – are vulnerable to drone attacks. Fuel convoys are also historically exposed, she said. Smaller, more mobile bases, which don’t require as much diesel refueling, are a potential answer, she added.
“A diesel generator needs to be refueled every one or two days. In previous conflicts in the Middle East, these targets were our biggest targets for our adversaries because fuel convoys created repeatable paths,” Shivanandan said. “Our unit does not need resupply for three years.”
The army’s point of view
Jeff Waksman, the Army’s top energy official, likes to recite the popular military saying: “Amateurs talk tactics, professionals talk logistics.”
Waksman, a nuclear physicist by training, leads the Janus project as well as the previous Pele project for a transportable nuclear reactor. “As we look to the future of warfare, it is becoming more and more electric,” he said. Fortunereferring to drone warfare and much more.
“We have a lot of applications where being able to have a lot of energy, without needing to refuel for a long time, and being able to do it in a fairly transportable way, could be a complete game changer,” he said, noting that Janus is the Roman god of new beginnings and transitions. “So we’re trying to lead the nation on these microreactors.”
The Army’s goal is to accelerate the commercial success of microreactors and, therefore, make them more economical and more useful to the Army. After all, no company wants to buy the first ones that are economically prohibitive, which is why the military steps in financially and then helps economies of scale take over. The Janus Project plans to finance 20 microreactors for the Lower 48 bases until the early 2030s.
Then he said: “We’re certainly thinking about what it would take to move the reactors to more austere locations,” Waksman said, citing tactically strategic positions in the Arctic or Pacific islands to power missile defense systems and more. But he’s not yet ready to push for close-combat microjets. “We have no plans at the moment to take them to conflict zones. We want to be clear about that.
“You can see potential game-changing capabilities in the future,” he said. “But first we need to make sure it works safely and affordably in the lower 48 states.” And he warned against the military – or the public – getting ahead of themselves. “It’s one thing to run a reactor for five minutes at low power. It’s another to run a reactor at full power, which no one has done with these microreactors.”
What is also clear is that the military sees the potential of nuclear power as the most reliable and stable energy source for the future. The initial goal is not to power entire bases, but to focus on critical operations that need to stay online during network outages, especially in the age of AI and growing cybersecurity threats. The microreactors would serve as permanent energy sources, not just backup generation.
“Most of the electricity is not necessarily what we consider critical, operationally. If people can’t eat lunch, that’s a problem, but it’s not critical to national security,” Waksman said. “We are focused on critical operations at these facilities.”
Competing approaches
While many of the next-generation nuclear leaders are startups, General Atomics, 71, also aims to lead the way with an optimized commercial version of its training and research TRIGA reactor, originally developed in the late 1950s.
General Atomics’ GA-TES (Tactical Energy System) reactor, which would increase from 5 to 20 megawatts as needed, should first be installed at Fort Hood in Texas.
Christina Back, GA’s vice president for nuclear technologies and materials, essentially agrees with Antares’ Bramble that strong commercial demand for nuclear will be at both ends of the spectrum: large, next-generation reactors, such as the Westinghouse, the 1.1-gigawatt AP1000, and microreactors. Mid-sized small modular reactors (SMRs) under development may struggle to find enough takers.
The GA-TES reactor is air-cooled, so it does not even need to be placed near water, as in traditional light-water nuclear power plants.
“It’s good for remote places. It costs a lot of money to move the fuel up there. You don’t want to have to keep transporting coal or natural gas or whatever,” Back said, citing everywhere from Guam to Alaska and noting that General Atomics’ system only needs to be refueled every four to six years.
In competition with each other, microreactor manufacturers do not hesitate to criticize each other, even if they do not mention them by name. Back said General Atomics doesn’t need to participate in Trump’s criticality race because TRIGA test reactors have been proven for nearly 70 years.
Back also said a one-megawatt reactor seems unnecessary because the military needs more power for its base and commercial demand is limited. Taking a microreactor into a combat zone is impractical due to the many days required to set it up and take it down.
General Atomics is well positioned and has no need to boast, she said. “As a company, we don’t have to worry about seed money for the next Series A, so we’re very careful about what we say.”
Radiant and others would of course disagree. After all, Radiant’s Kaleidos aims to be the most transportable, while most microreactor systems are designed to stay in one place for extended periods of time, although they can be mobile. Shivanandan said she was very “confused” by microreactor companies that require digging holes at least 50 feet into the ground.
“Once you dig a hole in the ground and put a reactor in it, it becomes a nuclear site forever,” Shivanandan said. “You’ve limited the customer base for these buried systems primarily to utilities. No (other) customer wants to remain a nuclear encryptor forever because business moves incredibly quickly.”
What the rivals agree on, however, is that they are excited about the Trump administration’s efforts to speed up the authorization of nuclear projects, as well as growing bipartisan support within Congress as Japan’s 2011 Fukushima nuclear disaster recedes from the forefront of minds.
“We tend to be very conservative because the nuclear industry can’t afford an accident,” Back said before adding another analysis. “We’re taking a little longer than the megawatt startups that are rushing to show it works, because we’re building something to last.”
Gn bussni
