Radiant CEO Doug Bernauer on Portable Nuclear Microreactors & the Future of Clean Energy
From SpaceX to Radiant
Radiant CEO Doug Bernauer on Portable Nuclear Microreactors & the Future of Clean Energy
Over a month ago I visited Radiant in El Segundo to meet Doug, CTO Bob, COO Tori, and the team to learn more about their portable nuclear reactor, Kaleidos (thank you to Michelle Volz at a16z’s American Dynamism Fund for the intro!). Aside from having one of the coolest websites I’ve seen to date, the tour of the physical location was equally impressive.
I was blown away by their engineering expertise, safe design & rapid development, in-house software systems, as well as all of the fun they’re having along the way.
Amid stagnating nuclear energy progress in the U.S. over the last 50 years, Radiant has demonstrated over the last 5 years that they have the team and capabilities to lead the next frontier. It’s astonishing. They’re fast.
Read more on Radiant below, or jump to the bottom to get timestamps of our conversation covering Doug’s background at SpaceX, the history of nuclear, development of Kaleidos, and how they’re impacting the future of clean energy.
→ Watch + listen to the full episode: Spotify, Apple, YouTube
From SpaceX to Radiant
Doug’s background is one not many can replicate. This includes working on Grasshopper, SpaceX’s first rocket with landing legs, to Hyperloop (also where him and Co-Founder & CTO Bob Urberger worked together), the Boring Company, and even space lasers(!!). While most of Doug’s work was centered on creating a multi-planetary future, it’s where he ultimately got the inspiration to build Radiant and provide safe & clean portable energy resources here on earth.
Radiant is a clean energy startup building portable nuclear microreactors to replace diesel generators. The Company has raised over $50M to date. Their last round was a $40M Series B in 2023 led by a16z, alongside other notable funds like Founders Fund, Decisive Point, McKinley Alaska, Draper Associates, Cantos, and BoostVC. Prior to that, Radiant raised a $10M Series A in 2022 led by Fred Wilson at USV.
“In recent years, wars, pandemics, ransomware attacks, and extreme weather events have pushed supply chains, power grids, and people to the brink — creating a real inflection point for industries that haven’t had reason to change historically,” says Andreessen Horowitz General Partner David Ulevitch, who leads the firm’s American Dynamism practice and has joined Radiant’s Board of Directors. “Radiant is bringing the innovation mentality and engineering rigor that they honed in aerospace to nuclear, another industry in dire need of renewed ingenuity and innovation.” [Radiant]
A climate-friendly alternative to diesel generators, Radiant's Kaleidos 1MW microreactor will be the world's first portable, zero-emissions power source that works anywhere. They plan to test their development reactor by 2026 and if successful, it will be the first new commercial reactor design to achieve a fueled test in over 50 years. Their microreactor can bring power to remote parts of the world and provide backup power for life-saving applications in hospitals or disaster-relief scenarios.
Render of Kaleidos at the Idaho National Lab DOME facility, Artist Ryan Seper
Kaleidos Technical Stats & Info
1 MW electric
1.9 MW heat, recoverable up to 80 degrees Celsius
Unit lifetime of 20 years with 4 cores, cores are replaced at the factory
Transportable by land, air, sea
Passive safety features
TRISO fuel is meltdown-proof and handles temperatures up to 1600 C
Helium coolant does not become radioactive, eliminating the impact of a release
Passive cooling air jacket keeps fuel and vessel temperatures controlled even if power is lost
Planning to test Kaleidos at the Idaho National Lab DOME in 2026, first commercial units in 2028
“[Radiant’s] team has been singularly focused on developing Kaleidos – the world’s first portable, zero-emissions power source that works anywhere. The safety of our 1MW microreactor has always been our priority. We use meltdown-proof TRISO fuel that’s been developed and tested by the Department of Energy and used in dozens of grid-scale reactors since the 1960s. However, unlike traditional reactors that rely on water, Kaleidos uses helium gas to transfer heat from the core. Helium does not become significantly radioactive, eliminating the impact of leaks.
Built to fit in a shipping container, Kaleidos can be installed overnight with no heavy infrastructure and lasts 20 years. The core is refueled back at a Radiant factory every 5 years, a unique feature of our streamlined and secure waste strategy. The fleet is autonomously operated by a fault-tolerant control system with 24/7 remote monitoring by the best trained staff. That means we learn more from every reactor, every day, adding fleet-level intelligence and modernizing safety through data science – something that is not possible with today's nuclear reactors.”
Read more → Why I Started Radiant: CEO, Doug Bernauer, tells Radiant's origin story and describes where we are headed
Interested in working with the team?
History of Nuclear Energy Stagnation
To put this in perspective, minimal progress has been made in the US over the last 50 years causing a wide gap of knowledge, research, and talent to propel the future generations. Luckily, Doug dives into this more in the episode and shares where Radiant is picking up the slack.
Resources
The future of Nuclear = Small, Mobile, Microreactors | Radiant [S3 by Jason Carman]
This SpaceX Engineer is Building a Mobile Nuclear Reactor [S3 Interview]
1930s Discovery of Nuclear Fission by Enrico Fermi
1940s Development of Chicago Pile-1 Reactor, Creation of AEC (Atomic Energy Commission)
1950s Creation of USS Nautilus (SSN-571) by Admiral Hyman Rickover
1960s-70s Commercial Power Reactors, Creation of Dept of Energy & NRC (Nuclear Regulatory Commissions, previously part of ‘AEC’)
High-Temperature Gas-Cooled Reactors (where TRISO fuel comes from)
TRISO Particles: The Most Robust Nuclear Fuel on Earth
Admiral Hyman Rickover: The Birth of Nuclear Power Documentary
Recommended by Doug!
Behind The Scenes at Radiant Industries US Dept of Energy
Get a tour of their new facilities!
Check out Age of Miracles by Packy McCormick:
Timestamps
(00:00) Intro
(01:42) Meet Doug Bernauer: Founder and CEO of Radiant
(02:30) Doug's Journey at SpaceX
(04:38) The Radiant Team and Their Backgrounds
(07:27) Founding Radiant Nuclear
(10:45) Innovative Nuclear Technology
(14:05) History of Nuclear Energy
(18:56) Public Sentiment and Nuclear Energy
(23:01) Challenges in Nuclear Industry
(24:42) Radiant's Commitment to Innovation
(25:25) Vertical Integration and Product Development
(27:28) Microreactors: A New Frontier
(28:40) Building the Nuclear Playbook
(32:09) Funding and Financial Strategy
(33:09) Remote Communities and Nuclear Power
(37:41) Technical Insights and Safety
(41:25) Team Building and Future Goals
(44:55) Wrap
Great Job Molly.