Google backs Proxima Fusion €411m raise for stellarator nuclear fusion reactors
Munich-based fusion startup Proxima Fusion closed a €411m Series B round at a €2.5bn valuation, led by XTX Ventures and East X Ventures with participation from Google, German energy giant RWE, and others. The funding marks Google's first investment in a European fusion company; Google has previously backed U.S. fusion builders including Commonwealth Fusion Systems (CFS), from which it has agreed to purchase future energy. Combined with €400m in Bavarian state funding, Proxima now has €800m committed toward its €2bn Alpha demonstrator stellarator, scheduled for completion in the early 2030s.
Proxima plans to build Alpha — a net-energy-gain stellarator (a twisted magnetic confinement vessel) — near the Max Planck Institute in Garching, then move to Stellaris, a commercial fusion plant targeting Gundremmingen, a decommissioned nuclear fission site in Germany. The company aims to secure the remaining €1.2bn for Alpha from German federal grants expected to be tendered later in 2026. Stellarators differ from tokamaks in their geometry: they twist to accommodate plasma quirks, enabling longer plasma stability without relying on the plasma's self-generated current for confinement.
The round reflects broader momentum in European fusion: in February 2026, the EU committed €330m to fusion energy research and deployment. Less than 5% of the global €7bn+ in private fusion funding since 2021 has gone to European companies; this investment signals a strategic push to close the gap. Proxima employs 200 people across Munich, Zurich, and Oxford and has raised €1.05bn total (including prior €650m rounds), making it Europe's best-capitalized private fusion company.
For infrastructure and energy teams watching grid decarbonization, Proxima's timeline (Alpha in early 2030s, commercial power in mid-2030s) and backing from industrial partners (RWE) and major cloud operators (Google) suggest stellarator technology is shifting from research to engineering deployment. Google's visible energy purchase commitments across fusion (CFS, now Proxima) signal corporate appetite for firm baseline nuclear-fusion power to support AI and data-center loads.
Sources
- Primary source
- deeptech.build
“Private capital has been building toward this moment for several years. Since 2021, more than $7 billion in private investment has flowed into fusion globally, across 53 companies now active in the space. European companies hold a disproportionately small share of that total: less than 5% of global private fusion funding”
- proximafusion.com
“Alpha will become the first stellarator to demonstrate net energy gain, meaning its plasma will generate more energy than it consumes. The demonstration stellarator will additionally allow Proxima and its partners to test and validate key fusion technologies under real-world conditions”