Proxima Fusion Raises $469 Million in Europe's Biggest-Ever Fusion Round

Proxima Fusion, a nuclear-fusion startup based in Munich, has raised 411 million euros, about $469 million, in what is being called the largest private fusion investment ever recorded in Europe. The round values the four-year-old company at 2.4 billion euros and takes its total funding past 650 million euros, a striking sum for a technology that has yet to produce a single commercial plant anywhere in the world.

The backers are notable as much as the number. The round was led by XTX Ventures, the investment arm of algorithmic-trading firm XTX Markets, and co-led by London’s East X Ventures, with German utility RWE and Alphabet’s Google joining as strategic investors. More than 90% of the capital came from European backers, a point Proxima stresses as it pitches itself as the continent’s answer to well-funded American and Chinese fusion efforts. Proxima is a spin-out of the Max Planck Institute for Plasma Physics and is building a stellarator, a design that uses twisting magnetic fields to bottle up the superheated plasma in which fusion reactions take place.

The money is earmarked for Alpha, a demonstrator meant to prove the design can generate more energy than it consumes, the make-or-break step between decades of laboratory research and a plant that can actually sell power. RWE, which recently agreed to help build a first stellarator plant on the site of a decommissioned fission reactor in Gundremmingen, Bavaria, gives the effort an industrial partner and a location. Proxima is aiming for an operational fusion power plant in the 2030s. If it succeeds, the timing could hardly be better: AI data centers are straining electricity grids and their operators are hunting for exactly the kind of clean, always-on power that fusion, if it ever works at scale, is meant to deliver.