In the high-stakes race to harness nuclear fusion—the process that powers the Sun—a German startup is betting on a complex but potentially game-changing design. Proxima Fusion, based in Munich, is developing a stellarator, a device that uses intricately twisted magnets to contain superheated plasma, with the goal of creating abundant, clean energy.
Francesco Sciortino, co-founder and CEO of Proxima Fusion, acknowledges the daunting path ahead. "I remember a few people said that the place where Proxima is today was impossible," he notes, reflecting on the skepticism surrounding fusion technology. The challenge lies in replicating the Sun's energy on Earth, which requires temperatures far exceeding those at the solar core to fuse hydrogen nuclei and release immense power.
While many fusion projects, such as the UK's Step initiative, rely on tokamaks—doughnut-shaped reactors with simpler magnetic coils—Proxima is pursuing the stellarator approach. Sciortino describes the difference vividly: "A tokamak is a 'beast' while the stellarator is a 'little cat.'" He explains that although stellarators are notoriously difficult to design and build, they offer superior plasma control once operational, likening them to a "dumb machine" that runs smoothly, much like a microwave oven.
The company's first major project, Alpha, builds on decades of research from Germany's Max Planck Institute for Plasma Physics and its W7-X stellarator. Proxima aims for Alpha to achieve net energy gain—producing more power than it consumes—with lessons applied to a future power plant called Stellaris. However, funding remains critical; Proxima recently secured €400 million from Bavaria and is seeking over a billion dollars in federal support, with a decision expected next year.
Sciortino admits to sleepless nights over the engineering hurdles, particularly the construction of Alpha's complex magnets. "The first magnet that we make will be very complicated and very expensive. But can we make it faster than people would expect, and can we drive down the cost?" he questions. Germany's manufacturing prowess, including a vast workforce skilled in CNC machining, gives Proxima an edge in precision engineering with specialized steel.
With over 50 fusion projects worldwide tracked by the Fusion Industry Association, the competition is fierce. Ryan Ramsey of Step highlights tokamaks' advantages: "They have demonstrated plasma performance closer to what's required for a fusion power plant... with comparatively simpler magnetic geometry." Yet, Sciortino is optimistic about Europe's role, noting, "We missed the digital wave, didn't we? But it turns out that we still have people being trained in manufacturing."
Proxima plans to test a prototype magnetic coil next year, followed by rapid production of 40 more for Alpha, targeting operation by the late 2020s—a timeline significantly shorter than the W7-X's decade-long development. As Sciortino puts it, "In, 2028, 2029 we need to be able to make magnets at a crazy, crazy speed." This push could position Europe at the forefront of a transformative energy industry, turning a once-impossible dream into a tangible reality.