Valar Atomics activates nuclear microreactor live to power Nvidia AI chip in first US demonstration

First Live Nuclear Microreactor Powers AI Chip

Valar Atomics achieved a significant milestone by activating its Ward 250 nuclear microreactor during a live demonstration, becoming the first startup to power a data center with small-scale nuclear technology 1

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. The California-based company partnered with Nvidia to demonstrate how the reactor could supply electricity to the Nvidia Blackwell AI chip architecture, marking the first time a nuclear microreactor powered AI infrastructure in the United States 2

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. During the event, a team member plugged an Nvidia RTX desktop unit into the reactor, which operated at 37% of its full capacity to activate the Blackwell-powered PC and run a web server at nuclearwebsite.com 1

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How the Ward 250 Nuclear Microreactor Works

CEO Isaiah Taylor explained the technical process behind the demonstration: "10 to 15th power uranium atoms are fissioning every second, producing 100 kilowatts of thermal energy" 1

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. The Ward 250 nuclear microreactor uses a High-Temperature Gas-Cooled Reactor framework, which Valar Atomics calls its Numenor architecture 3

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. Unlike traditional reactors that use water, this system employs pressurized helium to extract thermal energy, which flows into a thermal electric generator that creates electrical current 1

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. The design utilizes low-enriched uranium embedded within specialized TRISO fuel particles, which prevents core degradation during severe operational failures without requiring electrical backup systems or water pumps 3

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Addressing AI Energy Demands and Water Consumption

The partnership between Valar Atomics and Nvidia targets a critical challenge facing the tech industry: AI data centers' exponential power demands and water consumption 4

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. The companies plan to develop a 30-megawatt nuclear-powered data center in Utah that runs entirely independently of local municipal water supplies 3

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. Nvidia announced that its closed-loop liquid cooling for DSX data center design can reduce facility-cooling water consumption from roughly 2.6 million gallons per megawatt per year to near zero 2

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. By combining Valar's helium-cooled reactor with Nvidia's closed-loop cooling system, the proposed AI factory aims to eliminate environmental footprint concerns related to both power and water usage 5

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Growing Backlash Against Data Center Projects

Public resistance to AI data centers has intensified as communities experience massive increases in power and utility costs alongside water consumption issues 1

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. A Reuters/Ipsos poll revealed that only one in three Americans approve of the fast pace of data center construction, with 7 out of 10 saying they do not want a data center in their backyard 1

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. These environmental concerns have led to the delay or cancellation of at least 75 projects in just the first quarter of 2026 1

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. The industry's power needs have pushed companies to seek "behind-the-meter" plants that enable them to bypass permitting, public stakeholder engagement, and grid interconnection 2

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Race to Deploy Small Modular Reactors

Valar Atomics is one of about 10 nuclear energy startups in a Department of Energy reactor pilot program that set a goal to demonstrate three small reactors reaching criticality by July 4 2

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. While Valar Atomics claims to be the first startup to achieve power production, the Department of Energy reports that two other firms, Deployable Energy's Unity and Antares Nuclear's Mark-0, have also achieved criticality 1

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. AI tech giants and hyperscalers including Amazon, Google, Microsoft, Nvidia, and Oracle have invested in nuclear technologies as early as 2024, projecting that AI infrastructure would require massive amounts of power 1

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. President Donald Trump's administration sees small nuclear reactors as one of several ways to expand power generation, with Trump issuing executive orders in May aimed at quadrupling nuclear deployment 2

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Manufacturing Strategy and Regulatory Challenges

To address economic barriers associated with traditional nuclear construction, Valar Atomics plans to structure its architecture for factory mass production, focusing on fabricating units in small, modular sizes through modular manufacturing 3

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. However, advanced nuclear technology remains far from widespread commercial deployment, as federal regulators have not yet certified any next-generation advanced reactors for standard commercial sale in the United States 3

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. Valar joined litigation against the Nuclear Regulatory Commission last year alongside Texas and Utah, arguing that the commission does not have licensing authority over some nuclear microreactors and small modular reactors, seeking to give oversight to individual states 2

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. John Josephakis, an Nvidia global vice president, stated that "through this work with Valar Atomics, Nvidia is exploring how behind-the-meter, waterless advanced nuclear systems could support future AI factories built for the scale and reliability accelerated computing requires" 2

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. The demonstration represents a potential path forward for sustainability in AI development, though significant regulatory and technical hurdles remain before these nuclear-powered data center solutions become commercially viable at scale.