In short: X-Energy has raised $1.02 billion in the largest nuclear IPO on record, at $23 on the Nasdaq (up 21% from the range), with shares up 31% at the opening for a market cap of $12 billion. The offer was oversubscribed 15 times. The same company failed to close a $1 billion SPAC in 2023. The difference is AI-driven data center power demand: Amazon has committed to 5 GW by 2039, Dow Chemical and Centrica have signed on, and the SMR pipeline has doubled to 45 GW in 18 months.
In October 2023, X-Energy and Ares Acquisition Corporation mutually terminated a SPAC merger that valued the nuclear reactor developer at $1.05 billion. The deal fell through because public market conditions were, in the company’s words, “continuously volatile.” Ares was cancelled. X-Energy again went to raise private capital. Thursday, eighteen months later, X-Energy started trading on the Nasdaq under the ticker XE after surging 21% above its market-to-market range at $23 a share. It raised $1.02 billion, the largest nuclear public offering in history. The IPO was oversubscribed 15 times. One-third of institutional orders received zero shares. Shares opened at $30.11, a 31% pop, and traded as high as $31.33 during the session. The expected market capitalization exceeded 12 billion dollars. What changed between a failed SPAC and an oversubscribed IPO wasn’t the reactor. Xe-100 existed in 2023. What changed was that the world discovered that it needed power.
Reactor
The Xe-100 is a generation IV high-temperature gas-cooled reactor using a gravel bed design. Each unit produces 80 megawatts of electricity, is cooled by helium gas, fueled by special TRISO-X particles, tristructure isotropically clad uranium enriched below 20%. The fuel is packaged in ceramic and carbon spheres designed to not melt under any conceivable conditions and retain more than 99.99% of the fission products. The reactor does not require a large water supply, active safety systems, and emergency diesel generators to prevent fuel damage. It can ramp up from 40% to full power in 12 minutes, a load-following capability that adapts it to blend with the changing demand profiles of data centers. The design uses variables controlled by four operators. A typical nuclear power plant uses hundreds.
X-Energy’s TRISO-X fuel production facility in Oak Ridge, Tennessee has received a 40-year special nuclear material license from the Nuclear Regulatory Commission, the first new fuel production license in nearly 50 years and the first for a Category II facility. X-Energy’s flagship project, Dow Chemical’s construction permit application for the four-unit Xe-100 plant at its Seadrift operations 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 the Advanced Reactor Demonstration Program in 2020, allocating nearly $1.2 billion to develop Xe-100 and TRISO fuel. The technology has been developed for more than ten years. The capital to commercialize it came only when the customers came.
Customers
Amazon led X-Energy’s $500 million Series C-1 funding round in October 2024 and signed a binding agreement to buy up to five gigawatts of nuclear power from the company through 2039. The first project under this contract is the Cascade Advanced Energy Facility, a four-unit Cascade Advanced Energy Facility. 12 units and 960 megawatts. Amazon’s nuclear strategy goes beyond X-Energy: it bought Talen Energy’s data center campus adjacent to the Susquehanna nuclear plant in Pennsylvania for $650 million and secured a 1,920 megawatt power purchase agreement through 2042. It is investigating a 300-megawatt SMR project in Virginiatt. Amazon needs reliable, carbon-free primary load power for its AI data centers, which renewables can’t provide around the clock, and rising energy costs threaten cloud infrastructure Globally, geopolitical instability is reshaping the economics of electricity.
Dow Chemical’s Seadrift project will replace aging fossil fuel infrastructure with four Xe-100 units providing both electricity and industrial steam, with Fluor as the engineering partner. Centrica has signed a six gigawatt co-development deal for the UK’s first advanced reactor fleet. X-Energy’s total customer pipeline exceeds 11 gigawatts, equivalent to approximately 144 Xe-100 units. The IEA reported this week that AI data center electricity consumption will triple by 2030, and the pipeline of conditional abuse contracts between data center operators and SMR projects has nearly doubled from 25 gigawatts at the end of 2024 to 45 gigawatts today. AI companies are racing to secure data center capacityMistral alone raised $830 million to build a single 44-megawatt facility near Paris. The power to control these objects is the limit. Nuclear is the only carbon-free source that operates at full capacity regardless of the weather, time of day or season.
market
X-Energy is the third advanced nuclear company to go public after NuScale Power and Oklo. NuScale holds the only NRC design certification for a small modular reactor in the U.S., but has struggled commercially after canceling its flagship project with Associated Municipal Power Systems of Utah. Its shares have been volatile. Sam Altman-backed Oklo trades at a market capitalization of about $8.9 billion, with earnings up 248% in six months on the strength of its AI-core narrative and Aurora microreactor design. Google-backed Kairos Power secured the first NRC construction permit for a Generation IV reactor for the Hermes test facility in December 2023, but remains private. Gates’ venture, TerraPower, is building a sodium-cooled fast reactor with ARDP funding, along with X-Energy, but has not disclosed plans for an IPO.
X-Energy’s market capitalization of $12 billion on its first day of trading does not reflect its current revenue of about $163 million, nor the commercial readiness of its reactor. This reflects the market’s assessment that nuclear is no longer a regulatory burden to be tolerated, but a strategic asset to be had. Massive private capital flows into nuclear power Proxima Fusion is seeking two billion euros for a fusion test facility in Germany nuclear energy startups received a record amount of funding all of Europe. The World Economic Forum published an article this month titled “This energy crisis paves the way for a global nuclear renaissance,” citing the closing of the Strait of Hormuz and the energy demand of artificial intelligence as a dual catalyst. X-Energy’s 15 times IPO oversubscription is consistent with that thesis. Whether the thesis is true or not is a separate question.
Gap
The Xe-100 did not produce a single watt of commercial electricity. Seadrift construction permit under NRC review. The Energy Northwest project is in early development. The Centrica contract is a framework, not a signed power purchase agreement. X-Energy’s TRISO-X fuel plant is licensed but not yet producing fuel on a commercial scale. The company’s $1.02 billion IPO proceeds and about $1.8 billion it raised privately will fund the next phase of development, but advanced nuclear projects regularly face delays and rising costs that dwarf initial estimates. NuScale’s history is instructive: it received NRC design certification in 2023, lost its anchor customer the same year, and spent time searching for a replacement. Regulatory approval does not guarantee commercial viability. This only guarantees that the regulatory question is answered.
The gap between X-Energy’s market valuation and commercial reality isn’t just for nuclear. It’s the same loophole that exists in the AI infrastructure supply chain, from Nvidia’s forward-looking multiples to CoreWeave’s debt-financed expansion. Alternative approaches to power AI infrastructure including data centers in orbit. The market regards the future demand for AI computing as a near certainty and defines the power supply to run this computing as a binding constraint. X-Energy sits on the supply side of that constraint, with a government-backed reactor design, a 50-year fuel license that’s granted to everyone, an 11-gigawatt customer pipeline anchored by Amazon, and a stock price that assumes it all works out. A failed SPAC valued the company at $1 billion when no one needed power. The IPO valued it at $12 billion because everyone else does. The reactor has not changed. Bet the need won’t change either.
