Valar Atomics, a Hawthorne, California startup building small nuclear reactors to power artificial intelligence data centers, has raised $1 billion in Series B funding led by Sequoia Capital, tripling its valuation to $6 billion in a matter of months.
Sequoia partner Shaun Maguire led the round and is joining Valar's board, according to TechCrunch. The company also lined up a separate $200 million credit facility from Erebor and other banks, bringing its total new financing to $1.2 billion. Other participants in the equity round included Apandion Capital, Atreides Management, Conviction, Dream Ventures, HOF Capital, Point72, Riot Ventures, Snowpoint Ventures and Valor Equity Partners, according to Bloomberg.
The jump is striking: Valar was valued at roughly $2 billion after a $450 million round in April, meaning its price tag has tripled in about four months as investor appetite for nuclear-powered AI infrastructure accelerates.
Betting on Factory-Built Reactors
Valar is developing high-temperature, gas-cooled small modular reactors that use helium as a coolant, designed to be manufactured in fleets rather than built one at a time on-site — the model the company argues can cut construction costs and timelines compared with conventional nuclear plants. In June, Valar demonstrated its Ward 250 reactor powering an Nvidia Blackwell computing system and announced a partnership with Nvidia to develop a waterless 30-megawatt AI data center facility, according to Canary Media.
It took two years to complete the NOVA core. It took seven months to take Ward 250 critical.
Isaiah Taylor, CEO of Valar Atomics
The comment points to what Valar's backers are wagering on: an accelerating development timeline as the company moves from proving its reactor technology to mass-producing it. The new capital is earmarked for scaling manufacturing toward that goal.
Power-Hungry AI Data Centers
The round is the latest sign that data-center operators and their investors are treating electricity supply as a bottleneck as urgent as chip supply. AI infrastructure buildouts have strained regional power grids across the U.S., pushing hyperscalers and startups alike toward long-term power deals — including nuclear, gas and, increasingly, dedicated on-site generation — rather than relying solely on utilities. Valar's pitch is that small factory-built reactors sited near data centers can deliver firm, round-the-clock power without the multi-year interconnection queues that have slowed renewable and grid-scale projects.
Whether Valar can deliver reactors at the pace and cost its investors are betting on remains untested at commercial scale. The company has not disclosed a timeline for its first commercial deployment beyond describing plans to build fleets of reactors following the Ward 250 milestone.
