20VC: $5BN in Revenue, 7 to 7,000 Employees in 9 Months, 206,000 Tests in a Single Day: The Craziest Story in Startups: Curative with Fred Turner

Where this was said

Why Nuclear—and Could Subcritical Become Bigger Than Curative?

At 1:12:18 · chapter starts 1:10:00

Fred didn't set out to start a nuclear company — he went looking to invest in one, figuring his expertise in navigating highly regulated industries could accelerate an existing player. What he found instead was disappointment: almost everyone in nuclear was treating it as an engineering challenge, when the real barrier is regulatory. Safe nuclear reactors have existed since the 1960s; the engineering is solved. The problem is that the anti-nuclear push of the 1980s created a regulatory environment requiring absolute guarantees under once-in-a-million-year scenarios, which traditional criticality-balanced reactors cannot provide. Fred then stumbled upon the energy amplifier concept developed by Carlo Rubbia, the Nobel laureate and former CERN director, in the late 1980s. The design operates permanently at 0.97 criticality — always below the threshold at which a chain reaction sustains itself. A particle accelerator provides the extra neutrons needed to generate power. When the accelerator turns off, the reaction stops immediately. No matter what you do to the reactor, even 10x the accelerator power, criticality cannot be reached. This removes the fundamental guarantee problem from nuclear regulation. The only active construction of such a system is in China, based on a US design abandoned after Fukushima. Fred and his wife co-founded Subcritical to fill that gap, estimating each 300-megawatt deployment at approximately $1 billion in construction cost, financed through infrastructure-style equity-and-debt structures. He predicts coal will largely disappear from the energy mix over the next decade, and sees AI-assisted mechanical design as a key enabler for accelerating Subcritical's development.

Science

Subcritical Nuclear: The Reactor That Cannot Go Critical

20VC: $5BN in Revenue, 7 to 7,000 Employees in 9 Months, 20… · Jul 18, 2026 Science

Subcritical reactors operate permanently below the criticality threshold, meaning the reaction physically cannot run away. A particle accelerator provides the extra neutrons — and when you turn the accelerator off, the power stops completely. It solves the fundamental guarantee problem that has blocked nuclear regulation for 40 years.

1:11:10

1:13:50

2m 40s

♥ 0

“

You basically have this big on-off switch where you can control and you can guarantee that no matter what you do to it, the fission will never run away. Even if you put in 10 times as much power from the accelerator, it will never run away. There's nothing you can do to it to cause it to go critical.

Fred Turner

20VC: $5BN in Revenue, 7 to 7,000 Emplo…

♥ 0

“

I think today the current gen models can do every back office task we have at Curative. It's just a matter of deploying them, getting them set up, getting them configured, having the right policies.

Fred Turner

20VC: $5BN in Revenue, 7 to 7,000 Emplo…

♥ 0