Valar Atomics has closed a $1bn Series B financing led by Sequoia Capital, welcoming Sequoia partner Shaun Maguire to Valar’s board of directors. Sequoia was joined by Apandion, Atreides Management, Conviction, Dream Ventures, HOF Capital, Point72, Riot Ventures, Snowpoint Ventures, Valor Equity Partners, and other both new and longtime investors. Valar also announced the closing of a $200m credit facility led by Erebor Bank, as administrative agent, and JP Morgan, alongside Crescent Cove and Hercules Capital.
Valar said the Series B financing will make possible “the next mission critical evolution: from reactor deployment and long-term operations to fuel production”. Valar emphasised that the company will not rely on outside suppliers for the fuel needed to deploy and operate. “We will construct it ourselves in labs placed alongside the very reactors that same fuel will run. These reactors will bring unprecedented energy abundance that matches the scale of their production.”
Valar’s target is ambitious – to shift from a single experimental reactor to planetary-scale, mass-manufactured energy. The aim is to transition from building individual, project-based reactors to rolling out standardised advanced units from a central manufacturing line eventually producing multiple units per week. To unlock true economies of scale, Valar plans to deploy hundreds of its microreactors on concentrated, grid-independent campuses called Gigasites serving AI data centres starting with a planned 30 MWe AI facility in Utah alongside Nvidia.
The company has certainly demonstrated phenomenally rapid development. Valar Atomics, founded in 2023, emerged from stealth in February 2025. It was one of 11 companies selected in June 2025 by the US Department of Energy (DOE) for its Reactor Pilot Program (RPP) and was also one of four companies selected by DOE in September 2025 to take part in its Fuel Line Pilot Program. Using DOE authorisation, Valar completely bypassed the Nuclear Regulatory Commission (NRC) significantly accelerating progress.
Valar’s Ward 250 microreactor achieved initial zero-power fuelled criticality on 18 June – the second advanced reactor to hit criticality under the RPP, meeting the 4 July deadline set by Executive Order 14301. Following this physics verification, the team demonstrated power ascension, generating electricity on 1 July.
Valar connected an Nvidia RTX Spark desktop machine built on Blackwell GPU architecture directly to the Ward 250 at Valar’s test facility in Orangeville, Emery County, Utah. This was a symbolic proof-of-concept designed to prove that next-generation microreactors can directly power AI hardware. The reactor, operating at 37% of its intended power capacity, generated a small electrical current (around 100 kW) to power the processor and briefly host a live, public website. The experiment ran on the first attempt with the reactor
Ward 250 100kWt is a high temperature gas-cooled reactor (HTGR) design that uses TRISO (Tristructural Isotropic) fuel, helium coolant and graphite moderators. When fully operational, it is designed to scale up to 5 MWe. A 5 MWe commercial unit will likely have a core capacity of 12-15 MWt.
Valar began ground-breaking for the reactor and the on-site TRISO fuel fabrication facility at the Utah San Rafael Energy Laboratory (USREL) in Emery County, Utah in September 2025. This was the first time a DOE authorised reactor was built and operated entirely outside of a national laboratory.
Valar also developed a “NOVA Core” for cold criticality testing at Los Alamos National Laboratory (LANL) to validate the physics of the reactor before its full operation. In December 2025, the NOVA Core achieved zero-power criticality at LANL’s National Criticality Experiments Research Center (NCERC) at DOE’s Nevada National Security Site (NNSS).
In February, the unfuelled modular components of the Ward 250 were transported to March Air Reserve Base near Riverside, California, where they were loaded onto three US Air Force C-17 Globemaster III aircraft to be airlifted to Utah for final assembly and testing.
The reactor components were manufactured and constructed by Valar Atomics in Southern California, at their corporate headquarters in El Segundo and their research and development facility in Hawthorne. El Segundo handled the structural design, integration planning, and overall digital modelling. The Hawthorne Facility built the physical mechanical structures, advanced graphite moderators, microreactor shell, automation systems, control room interfaces, and telemetry configurations needed to run the reactor remotely from a minivan-sized shipping envelope.
Valar has a grandiose vision. “With every hour of its operation, Ward 250 generates engineering, manufacturing, and operational data to feed the reactors to follow. The same will go for every reactor that we build, resulting in exponentially simpler production, exponentially faster deployment, and exponentially more reliable operation. The continuous learning loop is the key that will bring manufacturing economics to nuclear power. It took two years to complete the NOVA core. It took seven months to take Ward 250 critical. With each reactor built, the tick rate will become smaller until Valar is producing tens, then hundreds, then thousands of reactors per year. Eventually, factories filled wall to wall with small modular reactors will allow a once unaffordable energy source to approach the cost of production.”
A long article in Tech Times pointed to some of the possible obstacles on this path. The Ward 250’s design target for commercial deployment is up to 5 MWe roughly 50 times the power it produced during the Nvidia demonstration. “The demonstration proved the reactor can produce electricity and deliver it to a real load. It proved neither that the system is ready for commercial deployment nor that the thermoelectric conversion architecture used at the test site would translate to the efficient power generation a commercial data centre requires,” Tech Times noted. “For commercial scale, Valar will need to move from the thermoelectric generator … to a closed Brayton cycle — a helium gas turbine — or a steam generator…. That engineering step, from test architecture to commercial architecture, is a significant one, and is part of what the $1 billion is designed to fund.”
AI racks now require 50-100 kWe per rack and the U. grid was not built for that density. Microsoft, Amazon, Google, and Meta have all signed direct nuclear power purchase agreements and invested in SMR startups seeking to bypass public utilities. Valar argues that a Ward reactor can be manufactured in a factory, shipped to a data centre site, and operated without drawing power from the public grid. Moreover, the reactors are helium-cooled avoiding the need for water intake from local aquifers. Utah’s governor signed new data centre development rules in May, following community opposition to the water and power demands of AI projects.
Tech Times said the hardest question is whether Valar can cross the regulatory gap between where it is now, operating under DOE RPP authorisation and where it needs to be to sell a single commercial kilowatt-hour of power, which would have to be be licensed by NRC.
The timeline for NRC licensing of a novel non-light-water reactor design is uncharted. NuScale’s VOYGR, a conventional pressurised-water design and the only SMR NRC has fully licensed – required more than a decade. The Trump administration’s executive orders directed NRC to target 18-month review timelines for new designs, this has not yet been tested against a commercial HTGR application. Complicating matters further, Valar has been simultaneously litigating against the NRC. In April 2025, the company joined states including Texas, Utah, Louisiana, Arizona, and Florida in a lawsuit challenging NRC licensing authority over certain small reactors. The litigation is ongoing.
The $1bn financing round gives Valar the capital to continue Ward 250 power operations and data collection in Utah, begin design work on larger commercial reactor variants, advance a Nvidia feasibility study, and prepare the regulatory case for NRC commercial licensing.
“What it cannot buy directly is the licensing itself. That process, for a novel HTGR design, will be measured in years,” Tech Times concluded. “The DOE Reactor Pilot Program that authorised Ward 250 was explicitly designed as a stepping stone – a way to generate operational data at small scale that can then be submitted to the NRC as the foundation of a commercial license application. As of the $1 billion announcement, Valar has not publicly filed that application.”
