Bottom line: X-Energy raised $1.02 billion in the largest nuclear IPO ever, priced at $23 (21% above range) on the Nasdaq, and shares rose 31% at the open, implying a market cap of $12 billion. The offering was 15 times oversubscribed. The same company failed to close a billion-dollar SPAC in 2023. The difference is AI-driven data center energy demand: Amazon committed to 5 GW by 2039, Dow Chemical and Centrica signed on, and SMR supply doubled to 45 GW in 18 months.
In October 2023, X-Energy and Ares Acquisition Corporation mutually ended a SPAC merger that had valued the nuclear reactor developer at $1.05 billion. The deal fell through because public market conditions were, in the company’s words, “persistently volatile.” Ares liquidated. X-Energy raised private capital again. On Thursday, eighteen months later, Energy X began trading on the Nasdaq under the symbol XE after pricing an upsized initial public offering at $23 per share, 21% above the top of its trading range. It raised $1.02 billion, the largest nuclear public offering ever recorded. The IPO was 15 times oversubscribed. One-third of institutional orders received zero allocation. Shares opened at $30.11, up 31%, and traded as high as $31.33 during the session. The implied market capitalization exceeded $12 billion. What changed between the failed SPAC and the oversubscribed IPO was not the reactor. The Xe-100 existed in 2023. What changed was that the world discovered it needed that power.
the reactor
The Xe-100 is a fourth-generation high-temperature gas-cooled reactor using a pebble bed design. Each unit produces 80 megawatts of electrical power, cooled by helium gas, fueled by patented TRISO-X particles, tristructural isotropic coated uranium enriched below 20%. The fuel is enclosed in carbon-ceramic spheres designed not to melt under any postulated conditions, retaining more than 99.99% of the fission products. The reactor does not require a large water supply, active safety systems or emergency diesel generators to prevent fuel damage. It can go from 40% to full power in 12 minutes, a load-following capability that makes it suitable for matching the varying demand profiles of data centers. The design uses four variables controlled by the operator. A conventional nuclear plant uses hundreds.
X-Energy’s TRISO-X fuel manufacturing facility in Oak Ridge, Tennessee, has received a 40-year special nuclear material license from the Nuclear Regulatory Commission, the first new fuel manufacturing license in approximately 50 years and the first for a Category II facility. The construction permit application for X-Energy’s flagship project, a four-unit Xe-100 plant at Dow Chemical’s Seadrift operations site in Texas, was accepted by the NRC in May 2025, with an 18-month review schedule. The Department of Energy selected X-Energy along with Bill Gates’ TerraPower for its Advanced Reactor Demonstration Program in 2020, committing approximately $1.2 billion to Xe-100 and TRISO fuel development. The technology has been in development for more than a decade. The capital to market it came only when customers did.
the clients
Amazon led X-Energy’s $500 million Series C-1 financing round in October 2024 and signed a binding agreement to purchase up to five gigawatts of nuclear power from the company by 2039. The first project under that agreement is the Cascade Advanced Energy Facility, a four-unit, 320-megawatt facility in Washington state developed with utility Energy Northwest, expandable to 12 units and 960 megawatts. Amazon’s nuclear strategy extends beyond Amazon needs reliable, carbon-free baseload power for AI data centers that renewables cannot provide 24 hours a day, and Rising energy costs threaten cloud infrastructure. globally as geopolitical instability reshapes the economics of electricity.
Dow Chemical’s Seadrift project will replace aging fossil fuel infrastructure with four Xe-100 units supplying electricity and industrial steam, with Fluor as an engineering partner. Centrica has signed a six-gigawatt joint development deal for the UK’s first fleet of advanced reactors. X-Energy’s total customer base exceeds 11 gigawatts, which is equivalent to approximately 144 Xe-100 units. The IEA reported this week that electricity consumption by AI data centers will triple by 2030 and that the portfolio of conditional supply agreements between data center operators and SMR projects has almost doubled from 25 gigawatts at the end of 2024 to 45 gigawatts today. AI companies race to secure data center capacityand Mistral alone raised $830 million to build a single 44-megawatt facility near Paris. The limitation is the power to manage those facilities. Nuclear energy is the only carbon-free source that operates at full capacity regardless of the weather, time of day or season.
the market
X-Energy is the third advanced nuclear company to hit the public markets, after NuScale Power and Oklo. NuScale holds the only NRC design certification for a small modular reactor in the United States, but has run into business problems after the cancellation of its flagship project with Utah Associated Municipal Power Systems. Its shares have been volatile. Sam Altman-backed Oklo trades with a market capitalization of about $8.9 billion on revenue that remains minimal, with its shares rising 248% in six months on the strength of the AI nuclear narrative and its Aurora microreactor design. Google-backed Kairos Power obtained the NRC’s first construction permit for a Generation IV reactor in December 2023 for its Hermes test facility, but remains private. Gates’ company TerraPower is building its Natrium sodium-cooled fast reactor with ARDP financing alongside X-Energy, but has not announced plans to go public.
X-Energy’s $12 billion market capitalization on its first day of trading reflects neither its current revenue, about $163 million, nor the commercial readiness of its reactor, which is still years away from first power. It reflects the market assessment that nuclear energy is no longer a regulatory burden to be tolerated but a strategic asset to be owned. Huge private capital is flowing into nuclear energy in both fission and fusion: Proxima Fusion seeks two billion euros for a fusion testing facility in Germany and Record funding for nuclear energy startups throughout Europe. The World Economic Forum published an article this month titled “This energy crisis is ushering in a global nuclear renaissance,” citing the Strait of Hormuz disruption and AI energy demand as twin catalysts. The oversubscription of 15 times the IPO of X-Energy is consistent with this thesis. Whether the thesis is correct is a different question.
the gap
The Xe-100 has not produced a single watt of commercial electricity. Seadrift’s construction permit is under review by the NRC. The Energy Northwest project is in its early stages of development. The Centrica agreement is a framework, not a signed power purchase agreement. X-Energy’s TRISO-X fuel facility is licensed but does not yet produce fuel on a commercial scale. The $1.02 billion the company raised in its initial public offering and roughly $1.8 billion raised privately will fund development through the next phase, but advanced nuclear projects routinely experience delays and cost overruns that dwarf initial estimates. NuScale’s story is instructive: It received NRC design certification in 2023, lost its major customer that same year, and has spent time searching for a replacement ever since. Regulatory approval does not guarantee commercial viability. It only guarantees that the regulatory question has been answered.
The gap between X-Energy’s market valuation and its commercial reality is not unique to nuclear energy. It’s the same gap that exists across the entire AI infrastructure supply chain, from Nvidia’s forward-looking multiples to CoreWeave’s debt-financed expansion to Alternative Approaches to Boosting AI Infrastructure including data centers in orbit. The market is pricing future demand for AI computing as a near-certainty and the power supply to run that computing as the binding constraint. X-Energy is on the supply side of that constraint with a reactor design that’s backed by the government, a fuel license that took 50 years to grant to anyone, an 11-gigawatt customer base backed by Amazon, and a stock price that assumes it will all work out. The failed SPAC valued the company at $1 billion when no one needed the energy. The IPO valued it at $12 billion because everyone does it. The reactor has not changed. The bet is that the need will not change either.
