Nuclear Fission

GE Vernova Hitachi Nuclear Energy

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Subsidiary of GE Vernova (JV with Hitachi)

GE Vernova Hitachi Nuclear Energy (GVH, formerly GE Hitachi Nuclear Energy) is the Wilmington, North Carolina-based nuclear alliance formed by GE (60%, now GE Vernova) and Hitachi (40%) in 2007, combining reactor design, services for the global boiling-water-reactor fleet, and fuel manufacturing through Global Nuclear Fuel. Its flagship BWRX-300 small modular reactor — a 300 MWe natural-circulation design derived from the NRC-certified ESBWR — is the first grid-scale SMR under construction in the Western world, with Ontario Power Generation building the first of four units at Darlington for service by the end of 2030. In the US, TVA's Clinch River construction permit application cleared its NRC staff safety evaluation in June 2026, backed by a $400M DOE award, and in March 2026 the US and Japanese governments announced up to $40B to deploy up to 10 BWRX-300s (3 GW) in Tennessee and Alabama under the US–Japan strategic investment framework. The order book extends across Poland (ORLEN Synthos Green Energy), Sweden (down-selected by Vattenfall), the UK (Generic Design Assessment completed December 2025), Estonia, Hungary and Saskatchewan. GVH also co-developed the Natrium sodium-cooled fast reactor with TerraPower, which began construction in Wyoming in 2026. Jason Cooper became President & CEO in January 2026.

Westinghouse Electric Company

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Private (Brookfield & Cameco)

Westinghouse Electric Company is the largest Western nuclear technology company, owned 51% by Brookfield (with institutional partners) and 49% by uranium miner Cameco since their $7.9B acquisition closed in November 2023. Nearly half of the world's operating nuclear reactors are based on Westinghouse technology, and its fuel and operating-plant-services businesses serve PWR, BWR, and VVER fleets globally — generating about $5.0B of revenue in 2025. Its flagship AP1000 reactor is the only fully licensed advanced large reactor operating in the US (Vogtle Units 3 and 4 in Georgia), with four more units operating in China and orders or advanced programs in Poland, Bulgaria, and Ukraine. In October 2025 the US government announced an $80B+ strategic partnership with Westinghouse, Brookfield, and Cameco to build a fleet of AP1000 and AP300 reactors across the United States, followed in June 2026 by a conditional $17.5B DOE loan commitment to finance long-lead components for up to 10 AP1000s. Alongside the large-reactor buildout, Westinghouse is developing the 330 MWe AP300 small modular reactor and the 5 MWe eVinci microreactor, which is slated for first fueled testing at Idaho National Laboratory and was selected for deployment at Malmstrom Air Force Base. Under CEO Dan Sumner, appointed in April 2026, the company sits at the center of the US nuclear renaissance.

NuScale Power

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Public (NYSE: SMR)

NuScale Power is a public small modular reactor developer commercializing its NRC-approved 77 MWe NuScale Power Module through ENTRA1-led deployments. In 2025-26 it advanced a nonbinding program with TVA for up to 6 GW of NuScale capacity (with CEO John Hopkins targeting a binding PPA by year-end 2026), secured a Final Investment Decision for the Romanian RoPower project, and launched a strategic petrochemical process-heat partnership with Ebara Elliott Energy. NuScale remains pre-deployment and ended Q1 2026 with about $1B in liquidity and capital resources, with 2026 centered on first-module manufacturing readiness — components for 12 modules are in production — fuel supply, and converting its development pipeline into binding projects.

Oklo

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Public (NYSE: OKLO)

Oklo is developing fast-fission power plants under its Aurora product line while building a vertically integrated nuclear business around power sales, fuel recycling, and radioisotopes. Aurora units are designed to produce 15-75 MWe and run on fresh, recycled, or down-blended fuel, targeting customers such as data centers, industrial sites, military facilities, utilities, and remote communities. Its first plant, Aurora-INL at Idaho National Laboratory, is advancing under DOE's Reactor Pilot Program — the DOE approved its Preliminary Documented Safety Analysis on June 11, 2026, leaving the final Documented Safety Analysis as the last safety-basis step before authorization. Oklo is deepening vertical integration through the June 2026 acquisitions of Oak Ridge precision manufacturer ARMEC and sodium-systems engineering firm Creative Engineers, plus its May 2026 selection for DOE's Surplus Plutonium Utilization Program, while Atomic Alchemy builds U.S. isotope supply, including the Groves test reactor in Texas that is targeting criticality in 2026.

TerraPower

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Active

TerraPower is a nuclear innovation company founded by Bill Gates and focused primarily on the Natrium sodium fast reactor with integrated molten-salt energy storage. In March 2026 the NRC issued Kemmerer Unit 1 the first construction permit for a commercial-scale advanced nuclear plant in the U.S., and on April 23, 2026 TerraPower and contractor Bechtel officially began plant construction in Wyoming, a build expected to mobilize roughly 1,600 workers. In January 2026 TerraPower signed a landmark agreement with Meta to develop up to eight Natrium plants in the U.S., marking a shift from a single demonstration toward a commercial fleet. The company remains pre-revenue, but Natrium has moved from development into full project execution under DOE's ARDP cost-share program.

Kairos Power

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Active

Kairos Power is commercializing its fluoride salt-cooled, high-temperature reactor (KP-FHR), which combines TRISO pebble fuel with FLiBe coolant in a compact, low-pressure design. The company runs an iterative, vertically integrated development model centered on Hermes 1, a 35 MWth demonstration reactor under safety-related construction in Oak Ridge, and Hermes 2, an electricity-producing demonstration plant for the TVA grid. In April 2026 Kairos broke ground on Hermes 2 — the first deployment under its Google-backed fleet plan totaling up to 500 MWe by 2035 — while a May 2026 NRC amendment extended Hermes 1's construction-completion deadline to April 2029 (Kairos now expects to finish building the test reactor in 2028). Kairos operates two ISO 9001:2015-certified sites (Alameda and Albuquerque) as it scales toward serial reactor-hardware production, and Hermes 2 is targeted to deliver first grid power around 2030.

X-energy

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Public (NASDAQ: XE)

X-energy is an advanced nuclear and fuel company commercializing the 80 MWe Xe-100 reactor and its TRISO-X fuel platform. In April 2026 the company priced an upsized IPO to begin trading on Nasdaq under the ticker XE, raising ~$1.1B in net proceeds, and on June 4 reported its first quarter as a public company with $43M of revenues and grant income, a $166.2M net loss, and roughly $2.05B of liquidity adjusted for IPO proceeds. Operational momentum has also stacked up: TRISO-X holds the first-ever Part 70 HALEU fuel license, the NRC issued a Finding of No Significant Impact for Dow's Seadrift project, and on June 2 X-energy filed the Xe-100 into the UK's Generic Design Assessment toward a planned 6 GW UK build-out with Centrica.

Holtec International

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Active

Holtec International is a vertically integrated nuclear technology and services company whose core businesses include used-fuel storage and transport systems, plant decommissioning, manufacturing, and nuclear project execution. Its flagship growth programs are the restart of the Palisades plant in Michigan, the first U.S. nuclear plant to return from decommissioning to operations status, and the SMR-300 small modular reactor platform, which Holtec is advancing at Palisades and in the UK with EDF. Holtec is also pursuing a large SMR-300 program in India — where a March 2025 U.S. DOE 10CFR810 authorization lets it share the design with partners Tata Consulting Engineers, Larsen & Toubro, and its Holtec Asia subsidiary — with a February 2026 plan to build up to 200 SMR-300s from an expanded manufacturing hub in Gujarat. After a confidential filing in February 2026, Holtec publicly filed a Form S-1 on July 10, 2026 for a Nasdaq / Nasdaq Texas IPO under the ticker HNUC — the S-1 disclosing $989M of revenue for the 12 months ended March 31, 2026 — in an offering that Renaissance Capital estimates could raise about $2 billion.

Aalo Atomics

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Active

Aalo Atomics is an Austin-based nuclear startup founded in 2023 by CEO Matt Loszak and CTO Yasir Arafat (former lead of INL's MARVEL microreactor) to mass-manufacture sodium-cooled reactors purpose-built for AI data centers. Its product line pairs the factory-built 10 MWe Aalo-1 reactor with the Aalo Pod, a 50 MWe 'extra modular' plant that clusters five reactors and is designed to install in months. Selected for the DOE's Reactor Pilot Program in August 2025, Aalo brought its Aalo-X Critical Test Reactor at Idaho National Laboratory to first criticality on July 4, 2026 — the fourth DOE-authorized advanced reactor to meet Executive Order 14301's deadline, less than eight months after groundbreaking. The company has raised over $300 million, including a $100M Series B led by Valor Equity Partners, and operates a 40,000 sq ft pilot factory in Austin with plans for a one-million-square-foot mass-production plant. Next up is Project Ascension: a commercial-scale reactor on the Aalo-X campus intended to power a co-located data center in 2027, with a long-term target of 3¢/kWh electricity.

Valar Atomics

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Active

Valar Atomics is an El Segundo-based nuclear startup founded in 2023 by Isaiah Taylor that develops small, mass-manufacturable high-temperature gas-cooled reactors (TRISO fuel, graphite moderator, helium coolant) intended to be deployed by the hundreds on grid-independent 'gigasites' producing power, hydrogen, and carbon-neutral synthetic fuels. As one of 11 projects in the DOE Reactor Pilot Program, its 100 kWt Ward250 test reactor at the Utah San Rafael Energy Lab achieved fueled criticality on June 18, 2026 — the first DOE-authorized reactor built and operated outside a national laboratory — then became the first of the pilot reactors to ramp to full power on June 23, and on July 1 generated 100 kW while powering Nvidia Blackwell chips in a live demo. The company and Nvidia are now exploring a 30 MW nearly waterless nuclear-powered AI data center in Orangeville, Utah. Valar has raised roughly $600M, including a $450M equity-and-debt round at a $2B valuation in March 2026 backed by Palmer Luckey and Palantir CTO Shyam Sankar, following a $130M Series A led by Snowpoint Ventures and a $19M seed led by Riot Ventures. It is also building Ward One, a 100 kW research microreactor in the Philippines with the Philippine Nuclear Research Institute, and is a co-plaintiff in a lawsuit seeking to exempt small test reactors from full NRC licensing. CEO Isaiah Taylor says Valar hopes to start selling power on a test basis in 2027 and become fully commercial in 2028.