X-Energy Raises $1.02B in Record Nuclear IPO as Amazon-Backed Reactor Developer Surges 31% on Nasdaq Debut
April 24, 2026 - 8:33 pm
In short: X-Energy raised $1.02 billion in the largest nuclear IPO on record, pricing at $23 (21% above range) on the Nasdaq, with shares surging 31% on opening to imply a $12 billion market cap. The offering was 15x oversubscribed. The same company failed to close a $1 billion SPAC in 2023. The difference? AI-driven data center power demand: Amazon committed to 5 GW by 2039, Dow Chemical and Centrica signed on, and the SMR offtake pipeline doubled to 45 GW in 18 months.
In October 2023, X-Energy and Ares Acquisition Corporation mutually terminated a SPAC merger that had valued the nuclear reactor developer at $1.05 billion. The deal collapsed due to “persistently volatile” public market conditions. Ares liquidated, while X-Energy turned back to raising private capital.
Eighteen months later, X-Energy began trading on the Nasdaq under the ticker XE after pricing an upsized initial public offering at $23 per share, 21% above the top of its marketed range. It raised $1.02 billion, the largest nuclear public offering on record. The IPO was 15 times oversubscribed. One-third of institutional orders received zero allocation. Shares opened at $30.11, a 31% pop, and traded as high as $31.33 during the session. The implied market capitalisation 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 the power.
The Reactor
The Xe-100 is a Generation IV high-temperature gas-cooled reactor using a pebble-bed design. Each unit produces 80 megawatts of electrical power, cooled by helium gas, fuelled by proprietary TRISO-X particles, tri-structural isotropic coated uranium enriched to below 20%. The fuel is encased in spheres of ceramic and carbon designed not to melt under any postulated condition, retaining more than 99.99% of fission products.
The reactor requires no large water supply, no active safety systems, and no emergency diesel generators to prevent fuel damage. It can ramp from 40% to full power in 12 minutes, a load-following capability that makes it suited to pairing with the variable demand profiles of data centers. The design uses four operator-controlled variables; a conventional nuclear plant uses hundreds.
X-Energy’s TRISO-X fuel fabrication facility in Oak Ridge, Tennessee, received a 40-year special nuclear material licence from the Nuclear Regulatory Commission—the first new fuel fabrication licence 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 timeline.
The Department of Energy selected X-Energy alongside Bill Gates’s TerraPower for its Advanced Reactor Demonstration Programme in 2020, committing approximately $1.2 billion to the Xe-100 and TRISO fuel development. The technology has been in development for over a decade. The capital to commercialise it arrived only when the customers did.