Deep Fission joins DOE event as nuclear pipeline hits 18.5 GW

Deep Fission Inc., the advanced nuclear developer that places small modular pressurized water reactors one mile underground, joined US Energy Secretary Chris Wright at Idaho National Laboratory on Thursday for an event celebrating the country's nuclear renaissance ahead of the 250th anniversary of American independence.

"The Golden Era of Nuclear Power event at INL highlights the next generation of nuclear technologies and the role advanced reactors will play in meeting growing demand for reliable, around-the-clock energy," Liz Muller, co-founder and chief executive officer of Deep Fission, said.

Deep Fission was selected as one of 10 companies for the Department of Energy's Reactor Pilot Program, authorized under Executive Order 14301. The program marks a shift in federal policy by enabling reactor testing and deployment on sites outside of national laboratories. The company's Gravity Nuclear Reactor approach combines established pressurized water reactor technology with a novel underground deployment model designed to simplify construction and enhance safety.

The company's participation follows its recent public listing on Nasdaq under the ticker FISN and the announcement of a customer pipeline representing as much as 18.5 gigawatts of potential generation capacity through letters of intent with data centers, industrial partners and strategic collaborators. Deep Fission is advancing development of its first reactor project in Parsons, Kansas, as part of the DOE pilot program.

Underground Reactor Design Targets Cost and Safety

Deep Fission's reactor design places a small modular pressurized water reactor — typically less than 300 megawatts of electric capacity — in a borehole approximately one mile underground. The approach uses the surrounding geology as a natural containment structure, eliminating the need for the massive concrete containment domes required by conventional nuclear plants. The company says this model can reduce construction costs and timelines compared with traditional large-scale reactors, though it has not disclosed specific cost estimates or a target date for first power generation.

The underground deployment also addresses a key challenge for the nuclear industry: site selection and community acceptance. By placing the reactor deep below the surface, the design reduces the surface footprint and visual impact. The company has not yet filed a license application with the Nuclear Regulatory Commission, and the timeline to commercial operation remains dependent on the DOE pilot program's progression.

Nuclear Sector Sees Renewed Policy Support

The event at INL comes as the US nuclear industry benefits from multiple policy tailwinds. The Inflation Reduction Act includes production tax credits for existing nuclear plants and investment tax credits for new advanced reactors. The DOE's Reactor Pilot Program, launched under the current administration, provides a pathway for testing and deployment outside traditional national laboratory sites.

INL, the nation's lead nuclear energy research laboratory, has been central to multiple advanced nuclear projects. Lightbridge Corp., another advanced fuel technology company, recently completed the first irradiation campaign of its fuel material samples at INL's Advanced Test Reactor, with post-irradiation examination expected to begin later this year. The laboratory's work spans fuel testing, reactor design and materials science for both conventional and advanced reactor technologies.

Deep Fission competes in a growing field of advanced nuclear developers including NuScale Power, TerraPower and Oklo, each pursuing different reactor designs and deployment strategies. NuScale's small modular reactor design received NRC certification in 2023, while TerraPower's Natrium reactor, backed by Bill Gates, is under construction in Wyoming. Oklo, which went public via SPAC merger in 2024, is developing a liquid-metal fast reactor.

For investors, Deep Fission's 18.5 GW pipeline represents potential revenue if the letters of intent convert to binding contracts, but the company faces significant regulatory and technical hurdles before any reactor can generate power. The stock, trading on Nasdaq under FISN, offers exposure to the nuclear renaissance theme but carries the execution risk common to pre-revenue advanced nuclear developers. The DOE pilot program provides a government-backed pathway that could accelerate regulatory timelines, though no commercial operating date has been set.

This article is for informational purposes only and does not constitute investment advice.