A high school dropout’s nuclear startup just landed $1B from Sequoia at a $6B valuation

Isaiah Taylor left high school at 16. Three years after founding Valar Atomics in California, he's sitting across the table from Sequoia Capital, which just led a $1 billion Series B that values the company at $6 billion. That's triple the $2 billion mark Valar carried after its $450 million round back in April 2026. Apandion, Atreides Management, Conviction, Dream Ventures, HOF Capital, Point72, Riot Ventures, Snowpoint Ventures and Valor Equity Partners all joined the round, and a separate $200 million credit facility led by Erebor Bank, with J.P. Morgan, Crescent Cove and Hercules Capital, pushed the new financing to $1.2 billion total, earmarked for mass production.

The timing isn't an accident. On June 18, Valar's Ward 250 reactor reached self-sustaining criticality. A week later, that same reactor generated electricity to power an Nvidia Blackwell chip in a live demo — the first time an advanced reactor has directly powered AI infrastructure. Sequoia partner Shaun Maguire joined Valar's board days after that demonstration. Taylor's framing of the milestone is blunt: the NOVA core took two years to build, but Ward 250 went critical in seven months. As he put it, one reactor is a project; a fleet requires manufacturing.

Taylor's original pitch was that nuclear power's real problem was never the physics — it was that every plant gets built as a bespoke, one-off construction job. Valar's answer is small, high-temperature gas-cooled reactors designed to come off a factory line rather than a custom build site. The company is also building its own fuel supply instead of sourcing it from outside vendors, with fuel labs planned right alongside the reactors that will burn that fuel. Earlier backers, including Palmer Luckey, Palantir's Shyam Sankar and Lockheed Martin board member John Donovan, put money in through a $130 million round in November 2025 led by Snowpoint Ventures. Along the way, Valar built a Ward Zero prototype, hit cold criticality on its NOVA reactor core working with Los Alamos National Laboratory, and got picked for U.S. Department of Energy pilot programs tied to reactor deployment and the supply chain for high-assay low-enriched uranium fuel.

Valar isn't the only nuclear startup cashing in on AI's appetite for electricity this year. Antares pulled in $470 million for reactors aimed at military bases, X-energy raised $1 billion through its IPO, and Last Energy closed $100 million for reactors pitched straight at data centres. Valar's $1 billion round is larger than those three combined, which says something about how aggressively Sequoia is willing to price a company that, right now, still runs a single working reactor. And unlike those competitors, who sell reactor hardware and let someone else handle fuel, Valar wants to control both ends. Whether that's the smart, defensible move or the slow one is genuinely unclear — the only evidence so far is Valar's own build timeline, which is moving fast on paper but still unproven at any real scale.