X-energy, a nuclear energy startup backed by Amazon, filed to raise up to $800 million in an initial public offering on April 15, marking one of the most significant steps yet for an advanced nuclear company toward the public markets.
X-energy, a developer of advanced small modular reactors (SMRs), began pitching prospective investors on its initial public offering this week, seeking to raise as much as $800 million as it looks to accelerate the commercialisation of its next-generation nuclear technology.
The company, which counts Amazon among its prominent backers, is pushing into public markets at a time of growing corporate and government interest in nuclear power as a reliable, low-carbon energy source. Technology companies in particular have been exploring nuclear agreements to meet surging electricity demand driven by data centres and artificial intelligence workloads.
X-energy is focused on its Xe-100 reactor design, a high-temperature gas-cooled pebble bed reactor intended to be smaller, safer, and more modular than conventional nuclear plants. The company has argued that its design can be factory-built and deployed more quickly than traditional large-scale nuclear infrastructure.
Amazon Web Services signed a landmark agreement with X-energy in 2023 as part of a broader push by the tech giant to secure nuclear power for its data centre operations. That deal helped raise the startup's profile and signalled growing confidence from major technology players in the viability of advanced reactor concepts.
The IPO filing comes as the broader nuclear sector experiences a revival of investor and policy interest. The Biden administration provided significant funding to advanced nuclear projects through the Department of Energy, and bipartisan congressional support for nuclear energy has remained comparatively strong. Several other SMR developers are also in various stages of development and fundraising, reflecting a broader bet that nuclear power will play a central role in decarbonising electricity grids.
However, the path to commercialisation for advanced nuclear companies remains long and capital-intensive. X-energy and its peers have yet to build and operate a commercial reactor at scale, and regulatory approval from the Nuclear Regulatory Commission is a complex, multi-year process. Past nuclear ventures, including NuScale Power — which went public via a SPAC merger — have faced setbacks including cost overruns and cancelled projects.
Details on the IPO's pricing, timeline, and exchange listing had not been fully disclosed at the time of publication. The offering will be closely watched as a barometer of investor appetite for pre-revenue advanced nuclear companies.
Analysis
Why This Matters
- A successful IPO would provide X-energy with significant capital to advance reactor development and regulatory approvals, potentially accelerating the commercialisation timeline for advanced nuclear in the US.
- The offering tests whether public market investors are willing to back capital-heavy, long-horizon nuclear startups — a result that could influence funding conditions for the entire advanced nuclear sector.
- Growing demand for clean, firm power from tech giants signals a structural shift in how nuclear energy is financed and who its customers may be.
Background
Nuclear energy fell out of favour with investors and policymakers for decades following high-profile accidents at Three Mile Island, Chernobyl, and Fukushima, and persistent cost overruns at large conventional plants. The Vogtle expansion in Georgia, the only new conventional nuclear plant completed recently in the US, came in years late and billions of dollars over budget.
Advanced reactor concepts — including SMRs and high-temperature gas-cooled designs — emerged as a potential answer, promising factory manufacturing, modular deployment, and passive safety features. The US government, through the Department of Energy's Advanced Reactor Demonstration Program, awarded X-energy a cost-sharing contract in 2020 to build a demonstration plant, providing a measure of public validation.
The past few years have seen renewed corporate interest, particularly from technology companies facing enormous electricity demands from AI infrastructure. Amazon, Google, and Microsoft have all struck nuclear power agreements, providing a new class of anchor customers that did not exist in earlier nuclear development cycles.
Key Perspectives
X-energy and Supporters: The company argues its Xe-100 design offers a safer, scalable path to zero-carbon baseload power, and that corporate partnerships with major technology firms de-risk its commercial prospects. Backers contend the IPO proceeds will fund the critical steps needed to bring a demonstration reactor online.
Investors and Analysts: Public market investors will scrutinise the company's pre-revenue status and long development timeline. The cautionary tale of NuScale — which went public, then saw its lead project cancelled amid cost concerns — may weigh on sentiment, raising questions about whether advanced nuclear economics pencil out at commercial scale.
Critics and Skeptics: Nuclear watchdog groups and some energy analysts argue that SMRs remain unproven at commercial scale and that cost estimates are speculative. Critics also point to the lengthy NRC licensing process as a structural barrier that could delay revenue generation well beyond investor expectations.
What to Watch
- The final IPO pricing and investor demand, which will indicate how much confidence public markets have in the advanced nuclear sector.
- Progress on X-energy's DOE-funded demonstration project and any updates to its NRC pre-application review timeline.
- Whether other SMR developers follow X-energy to public markets, and how the broader nuclear startup funding environment evolves in response to this offering's reception.