Proxima Fusion Raises €411M, Onboards Google als New Strategic Investor
Munich-based fusion startup Proxima Fusion has closed the largest private funding round for nuclear fusion in Europe to date. On board as strategic investors: Google and RWE. The company’s valuation climbs to €2.4 billion.
European fusion research is getting fresh capital at record levels: Proxima Fusion announced a €411 million funding round on Monday. The Max Planck spin-off from Munich is now valued at €2.4 billion, definitively joining the ranks of Europe’s deep-tech heavyweights. It is one of the largest private investments in the European tech sector this year – and the largest private fusion financing on the continent to date.
The round was led by XTX Ventures and East X Ventures. Particularly notable is the list of strategic investors: alongside Google, German energy giant RWE is also joining – a signal that both tech companies with enormous electricity needs and established utilities are increasingly treating nuclear fusion as a serious option. Other backers include KfW Capital, Germany’s Federal Agency for Disruptive Innovation SPRIND, and numerous existing investors doubling down.
Stellarator Instead of Tokamak
Proxima Fusion was founded in 2023 as a spin-off of the Max Planck Institute for Plasma Physics and builds on the scientific findings of the Wendelstein 7-X programme in Greifswald. Unlike many competitors betting on the tokamak design, the company is pursuing the stellarator concept – specifically a so-called QI-HTS model.
A stellarator is a magnetic confinement reactor that holds plasma hotter than 100 million degrees in a complex, helical magnetic field geometry. The approach is considered more challenging to engineer, but promises more stable continuous operation. A key building block are high-temperature superconductors (HTS), which Proxima is working intensively to develop and manufacture – they are meant to generate the extremely strong magnetic fields required to confine the plasma.
“Alpha” as the Bridge to a Power Plant
The fresh capital will primarily flow into the “Alpha” project: a stellarator demonstrator designed to prove net energy production, to be built near Munich. Partners are the Free State of Bavaria, the Max Planck Institute for Plasma Physics, and RWE. “Alpha” is intended to serve as the link between fundamental research and commercial application.
The long-term goal goes by the name “Stellaris”: the first commercial fusion power plant, slated to come online within this decade. A concrete site has already been identified – the grounds of the former Gundremmingen nuclear power plant in Bavaria, where Proxima plans to build a fusion power plant together with RWE. The symbolism is hard to miss: where nuclear fission once supplied electricity, nuclear fusion is set to feed the grid in the future.
With the new funds, Proxima Fusion also plans to significantly expand its engineering, manufacturing, and operations teams at its sites in Germany, Switzerland, and the United Kingdom.
Between Euphoria and Scepticism
As large as the investment sums are, the debate around the technology remains just as contentious. Advocates see nuclear fusion as the ultimate energy source: virtually unlimited fuel, no CO2 emissions during operation, no long-lived high-level radioactive waste, and – unlike nuclear fission – no risk of an uncontrolled chain reaction. The exploding electricity demand of AI data centres in particular has massively fuelled the interest of tech companies such as Google, Microsoft, and OpenAI CEO Sam Altman (an investor in US competitor Helion) in fusion energy. Governments in the US, the UK, Germany, and China are also pumping billions into research.
Sceptics, on the other hand, point to a long history of broken promises: for decades, nuclear fusion was known as the technology that is “always 30 years away”. While the US-based NIF laboratory achieved a scientific net energy gain for the first time in late 2022, the industry remains far from an economically viable power plant. Unresolved issues include material durability under extreme neutron bombardment, the supply of the fuel tritium, and the simple question of whether fusion electricity can ever compete with ever-cheaper renewables plus storage. Critics also warn that the prospect of fusion in the distant future must not serve as an excuse to delay the rollout of climate-friendly energy sources available today. Whether Proxima Fusion can keep to its ambitious timeline – commercial electricity within this decade – will only become clear with the “Alpha” demonstrator.
