We've covered a company (Reflect Orbital) beaming sunlight from space to wherever Earth needs it. We've covered a company (Subsea Cloud) putting data centers on the ocean floor, next to the people actually using it. The theme is the same every time: stop building infrastructure in one place and hoping the world reaches it. Bring it to the world instead.
Radiant Nuclear is about bringing nuclear power anywhere on Earth. On a truck. In what looks like a shipping container.
But first — we need to talk about what Hollywood has done to your brain.
What the media and Hollywood have told you
Nuclear power has a PR problem. Between HBO's Chernobyl, decades of disaster movies, and a general cultural assumption that anything nuclear equals catastrophe — most people picture mushroom clouds, not a shipping container quietly powering a hospital.
Here's the number nobody puts in the headline: nuclear results in 99.8% fewer deaths than coal and 99.7% fewer than oil. Even including Chernobyl. Even including Fukushima. Even including Three Mile Island, where the containment worked and there are no confirmed immediate or long-term deaths directly linked to radiation exposure.
Chernobyl was a flawed Soviet reactor design with disabled safety systems during an unauthorized experiment. It has nothing in common with what Radiant is building.
Okay so what is Radiant building
The Kaleidos is a 1 megawatt microreactor. Shipping container sized. Travels by truck, plane, or sea. Installs overnight. Runs five years without refueling. Lasts 20 years. Zero water. Zero emissions.
It’s not the 1.21 gigawatts of power Doc Brown needed, but Radiant isn’t trying to time-travel.
Now, if you’re like Marty McFly asking yourself — “what the hell is a gigawatt?” — you’re not alone. To put it in perspective, 1000 megawatts equals 1 gigawatt. So a megawatt sounds small, right? Until you realize 1 megawatt can power roughly 1,000 American homes.
The fuel Radiant uses is called TRISO — ceramic-coated uranium beads that look exactly like Dippin' Dots and handle temperatures up to 1,600°C. And we all know it hits 90°F and your Dippin' Dots turn a puddle of sugar and milk at the bottom of your mini baseball helmet cup. TRISO handles 1,600°C. Practically impossible for it to melt down. And the coolant is helium, which doesn't become radioactive if released.
The pitch: most of the world runs on diesel generators in places the grid doesn't reach. Diesel is loud, polluting, expensive, and you have to keep shipping fuel to dangerous places. A significant portion of U.S. casualties in Iraq occurred during convoy and logistics operations. Radiant replaces the generator and eliminates the convoy. Each reactor core eliminates millions of gallons of diesel over its lifetime. Sign me up.
It's not a nuclear power plant. It's a better generator. Perhaps the most important one ever built.
The guy who started it
Doug Bernauer spent 12 years at SpaceX — including working on Grasshopper, the first reusable rocket prototype — before leaving to start Radiant in 2020.
While still at SpaceX, his team built an energy model for a Mars colony. Nuclear came back as the best answer. He then started studying reactor designs, regulations, and history in whatever time he had left after building rockets. Then the realization: nuclear doesn't just solve Mars. It solves Earth. Right now. Hell yeah.
"The hard part of even what SpaceX wants to do is the nuclear part," Bernauer has said. "I have to leave."
He left. Hundreds of millions raised since. Andreessen Horowitz. Founders Fund. Equinix — the world's largest data center company — signed a deal with deposits for 20 reactors. The US Air Force signed the first-ever agreement to deploy a microreactor at an American military base. First test reactor fires up this summer at Idaho National Lab. First commercial deliveries: 2028.
The factory
Radiant is building their production facility — called R-50, targeting 50 reactors per year — in Oak Ridge, Tennessee. Specifically on the K-27 and K-29 sites. The original plant there was called S-50. It enriched uranium for the atomic bomb during the Manhattan Project.
The same ground where America built the most destructive weapon in human history is now producing reactors designed to bring clean power to remote villages, disaster zones, and military bases. Ready?
The honest take
The reactor hasn't been tested yet. Summer 2026 is the target. Commercial deliveries in 2028. Nuclear timelines have a well-documented relationship with optimism — this is a heavily regulated industry for very good reasons and schedules slip.
But Radiant isn't trying to reinvent nuclear. They're taking proven fuel, proven physics, proven safety principles — and doing what SpaceX did to rockets. Factory built. Mass produced. Cost driven down through repetition and scale. Not a breakthrough. An execution.
If they pull this off
Power goes everywhere. Hospitals that go dark during hurricanes. Military bases running on diesel convoys. Data centers that can't get enough grid power to run AI. Remote communities that have never had reliable electricity in their history.
And eventually — Doug hasn't let go of this — Mars. The same reactor powering a military base in Alaska could be strapped to a Starship and sent to power the first human settlement on another planet.
He left SpaceX because nuclear was the hard part. Radiant is solving the hard part.
Go to the field: radiantnuclear.com
Want to work out here? Radiant is hiring in El Segundo, California — which is quietly becoming the most interesting zip code in deep tech. Engineers, Finance & Accountants, Biz Ops, and people who think "factory-built nuclear reactor delivered on a semi" is a reasonable sentence. First reactors ship in 2028. Get in early.
Open roles - radiantnuclear.com/careers
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