X-Energy’s IPO Marks a Milestone for Advanced Nuclear Power Amid AI-Driven Energy Demand

On Friday, April 24, 2026, X-Energy began trading on the Nasdaq under the ticker XEF, marking a significant moment for the advanced nuclear industry. The company’s shares opened at $30.11 after pricing its initial public offering at $23 per share — above the initial range of $16 to $19 — and closed the day 27% higher at $29.20. The offering raised more than $1 billion, making it the largest nuclear public offering in history.

This milestone comes as artificial intelligence and broader electrification trends intensify demand for reliable, carbon-free power sources. X-Energy’s high-temperature gas-cooled Xe-100 reactor, rated at 80 megawatts and scalable to 960 megawatts when clustered, is positioned to serve both electricity generation and hard-to-decarbonize industrial processes such as chemical production.

The company has yet to begin construction on any reactor facilities but reports an order pipeline exceeding 11 gigawatts, supported by partnerships with major corporations including Amazon, Dow, and Centrica. Prior to the IPO, X-Energy had raised over $1.4 billion in private funding, most recently a $700 million Series D round in November 2025, with backing from Amazon, Jane Street, ARK Invest, Citadel founder and CEO Ken Griffin, and Ares Management funds. The U.S. Department of Energy has also provided funding to the company.

X-Energy’s public listing distinguishes it from peers like Oklo and NuScale, which went public via special purpose acquisition company (SPAC) mergers. The firm had previously pursued a SPAC route but abandoned the plan in 2023 before opting for a traditional IPO.

In October 2024, Amazon’s Climate Pledge Fund joined Ken Griffin’s Citadel, affiliates of Ares Management Corporation, NGP, and the University of Michigan in a $500 million Series C-1 financing round. The investment supports the completion of X-Energy’s reactor design and licensing, as well as the first phase of its TRISO-X fuel fabrication facility in Oak Ridge, Tennessee. Amazon and X-Energy have also committed to bringing more than 5 gigawatts of new power projects online across the United States by 2039 through direct investments and long-term power purchase agreements, including an initial 320-megawatt project with Energy Northwest in central Washington.

This initiative represents the largest commercial deployment target for compact modular reactors (SMRs) to date and underscores the growing role of advanced nuclear in meeting future energy demands driven by AI data centers, industrial decarbonization, and grid resilience.

Key Takeaways

• X-Energy’s IPO raised over $1 billion, the largest nuclear public offering on record.
• Shares rose 27% on debut, closing at $29.20 after opening at $30.11.
• The Xe-100 reactor is an 80-megawatt high-temperature gas-cooled design, scalable to 960 megawatts.
• X-Energy has an 11-gigawatt order pipeline backed by Amazon, Dow, and Centrica.
• Amazon and Ken Griffin’s Citadel were anchor investors in both pre-IPO funding and the public offering.
• The company aims to deploy over 5 gigawatts of SMR capacity in the U.S. By 2039.
• X-Energy is the first major advanced reactor firm to pursue a traditional IPO after peers used SPACs.

Frequently Asked Questions

What is X-Energy’s Xe-100 reactor?

The Xe-100 is a high-temperature gas-cooled small modular reactor (SMR) that uses TRISO-based fuel. Each unit generates 80 megawatts of electricity and can be clustered with up to 11 additional units to reach 960 megawatts. Its high operating temperature enables employ in industrial applications beyond power generation, such as hydrogen production and chemical processing.

Why is Amazon investing in X-Energy?

Amazon is investing in X-Energy through its Climate Pledge Fund to secure carbon-free power for its operations, including data centers and fulfillment centers. The partnership supports the development and deployment of SMRs to meet Amazon’s goal of net-zero carbon by 2040, with a target of bringing over 5 gigawatts of new nuclear capacity online by 2039.

How does X-Energy’s IPO differ from other nuclear companies’ public listings?

Unlike Oklo and NuScale, which went public via SPAC mergers, X-Energy pursued a traditional initial public offering on the Nasdaq. The company had previously explored a SPAC route but abandoned it in 2023 before opting for a direct listing.