In a landscape dominated by the pursuit of nuclear fusion, Munich-based Proxima Fusion is pushing the boundaries of what is possible with its innovative stellarator design. Led by CEO Francesco Sciortino, the company aims to harness the power of fusion—the same process that fuels the sun—to deliver an abundant, clean, and emission-free energy source. However, the journey is fraught with challenges, and the path to a viable power station appears long and winding.
The Quest for Fusion Power
Proxima Fusion is not alone in its ambitions; it joins a global cohort of 53 organisations striving to unlock the potential of fusion energy. The concept of fusion involves fusing hydrogen isotopes, typically tritium and deuterium, to release vast amounts of energy. While on the Sun, gravitational forces keep this reaction stable, replicating it on Earth necessitates extreme temperatures and complex engineering solutions.
Traditionally, fusion projects have gravitated towards the tokamak design—a doughnut-shaped reactor employing powerful magnets to contain plasma. In contrast, Proxima’s approach utilises a stellarator, characterised by its intricate geometry. This design boasts twists and turns that could potentially enhance the control over the burning plasma, making it a compelling alternative despite its higher complexity and cost.
The Advantages of a Stellarator
Sciortino describes the stellarator as a “dumb machine”, akin to a microwave oven, which once operational, could simplify the complexities associated with fusion. The Alpha reactor, Proxima’s flagship project, is set to leverage decades of research from Germany’s Max Planck Institute for Plasma Physics, particularly from its W7-X stellarator.
The goal is straightforward yet ambitious: Alpha must generate more energy than it consumes. Furthermore, the insights gained from Alpha are expected to inform the design of an even more advanced fusion power plant, dubbed Stellaris. However, this vision hinges on securing significant financial backing. Proxima has already secured €400 million (£340 million; $460 million) from the state of Bavaria and is pursuing over a billion dollars from the federal government, with a decision anticipated next year.
Competing in the Fusion Arena
While Proxima pursues its stellarator, the competition remains fierce, particularly from the UK’s STEP (Spherical Tokamak for Energy Production) project. Backed by the British government, STEP is set to create a prototype power plant on the site of a former coal-fired station in West Burton, Yorkshire. Ryan Ramsey, Director of Organisational Performance at STEP, highlights the advantages of the tokamak approach, which benefits from a wealth of experimental data and simpler magnetic geometries that facilitate manufacturing and maintenance.
However, Sciortino is acutely aware of the hurdles awaiting Proxima. He often reflects on the feasibility of constructing the intricate magnets essential for the stellarator design at a pace and cost that render the project economically viable. “The first magnet will be very complicated and very expensive,” he admits, emphasising the importance of efficiency in both production and cost reduction.
Manufacturing Expertise in Europe
Proxima’s success may hinge on Germany’s manufacturing prowess, which boasts a robust workforce skilled in operating CNC machines—crucial for the precision machining required for the expensive steel used in the magnets. With an estimated 550,000 CNC machinists in Germany compared to 350,000 in the United States, Proxima is well-positioned to leverage this expertise.
The company is currently constructing a prototype magnetic coil, anticipated to undergo testing next year. This coil will feature one of the most complex geometries in the world, and, upon successful testing, Proxima plans to manufacture 40 additional coils for the Alpha reactor. A dedicated magnet factory is already in the works, with ambitious production targets set for 2028 and 2029.
Sciortino believes that Europe has a unique opportunity to lead the fusion industry, having missed the digital revolution. He asserts, “We still have people being trained in manufacturing,” which could position the continent at the forefront of this transformative energy sector.
Why it Matters
The pursuit of fusion energy represents a potential turning point in the global energy landscape. As Proxima Fusion embarks on its challenging journey with the stellarator, the outcomes could redefine our approach to clean energy. Success in this field not only promises a sustainable power source but also revitalises manufacturing sectors across Europe, fostering innovation and job creation. The race for fusion is not merely a scientific endeavour; it embodies the hope for a cleaner, greener future.