Shares in X Energy, the London-listed nuclear technology company, surged more than 12% in after-hours trading on Wednesday evening, following unconfirmed reports that the firm is in advanced negotiations to supply small modular reactors (SMRs) to a major US data centre operator.
The jump, which pushed the stock above 850p in extended trading, came after a Bloomberg report citing sources familiar with the matter suggested the deal could be worth several billion pounds and involve the deployment of multiple SMR units to power AI and cloud computing facilities. Neither X Energy nor the reported counterparty has commented publicly.
The after-hours rally marks a sharp reversal for the stock, which had fallen nearly 8% over the previous month amid broader weakness in the clean energy sector. Analysts at Liberum noted that if confirmed, the deal would validate X Energy's SMR technology at a commercial scale and could unlock significant recurring revenue from the fast-growing data centre market.
“The hyperscalers are desperate for baseload, carbon-free power that doesn't depend on weather conditions,” said Dr Emily Hartfield, energy analyst at Canaccord Genuity. “Nuclear SMRs are increasingly seen as the only viable option for 24/7 clean power at the scale required by AI workloads. This rumour, if true, would be a game-changer for X Energy and for the UK nuclear supply chain.”
The broader FTSE 100 closed flat on Wednesday at 8,214 points, while the FTSE 250 added 0.3%. X Energy is listed on the AIM market, which rose 0.5% on the day. Other UK nuclear-related stocks, including Rolls-Royce (which develops its own SMR design), saw modest gains in sympathy with the news.
For UK pension holders and retail investors, the development underscores the growing intersection between technology infrastructure and energy policy. Many UK pension funds hold indirect exposure to nuclear energy through diversified clean energy funds and AIM-listed growth stocks. The potential deal also highlights the UK government's push to position Britain as a global leader in SMR technology, with ministers expected to announce the next phase of the SMR selection process later this year.