Nuclear Fission

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 it advanced a nonbinding program with TVA for up to 6 GW of NuScale capacity, completed Phase 2 FEED work for the RoPower project in Romania, and expanded its industrial-process-heat positioning. NuScale remains pre-deployment and ended Q1 2026 with about $1B in liquidity and capital resources, with 2026 centered on manufacturing readiness, 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. Through Atomic Alchemy and its fuel-cycle programs, Oklo is also building U.S. isotope supply and recycled-fuel infrastructure alongside its reactor deployment strategy.

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 granted Kemmerer Unit 1 the first construction permit for a commercial-scale advanced nuclear plant in the U.S., and on April 23, 2026 TerraPower officially began plant construction in Wyoming. 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 is using an iterative, vertically integrated development model centered on Hermes 1, a 35 MWth demonstration reactor under 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.

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 early 2026 TRISO-X received the first-ever Part 70 HALEU fuel fabrication license, X-energy began graphite production for its first Dow deployment, and the company priced an upsized IPO to begin trading on Nasdaq under the ticker XE. X-energy remains pre-revenue from commercial reactor operations, with execution now centered on Seadrift, fuel-fabrication buildout, and scaling an 11 GW pipeline.

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. In February 2026 the privately held company confidentially filed for a U.S. IPO, with reporting indicating it is seeking a valuation above $10 billion.