Proxima Fusion is a venture-capital-backed company working on making nuclear fusion a reality. It has open-sourced its reactor design in the journal Fusion Engineering and Design this week. Although the design is a highly technical piece of work involving a lot of engineering, the company wants to share this information with the fusion community, whether based in the U.S. or China.
In their bid to harness emission-free energy, scientists are working on developing nuclear fusion technology. Nuclear fission involves the splitting of atoms into lighter elements. Nuclear fusion works by fusing lighter atomic nuclei to form heavier elements. This releases huge amounts of energy without creating any carbon emissions or radioactive waste.
Nuclear fusion technology has shown great promise by delivering net energy gains on more than one occasion over the past few years. Research institutes and startups are now working to scale up that achievement and deploy it commercially to power the electrical grids. Much of the work in fusion energy research has taken place in the tokamak design of fusion reactors. Proxima’s approach is slightly different since it is a type of stellarator.
Tokamaks and stellarators use extremely strong electromagnets to confine and heat fusion plasma inside donut-shaped vessels. However, there is a significant difference in how they achieve this.
Tokamaks utilize a combination of electromagnets and current-induced plasma while stellarators operate only using magnets. This requires the stellarator vessel and magnet design to be much more complex while allowing the reaction to run continuously and safely.
Stellarators offer the advantage of continuous operation for longer durations and protection of materials from fatigue as opposed to tokamaks while also being simpler to operate.
About ten years ago, researchers at MIT showed how a commercial-scale fusion reactor using a tokamak design could be built. This was followed by a series of startups working with the tokamak approach to achieving nuclear fusion power.
Fusion energy technology has now reached another milestone moment, with the open-source release of a commercial-scale stellarator design.
Proxima Fusion was founded over two years ago. It is a spin-off from the Max Planck Institute of Plasma Physics (IPP). This institution developed the world’s most advanced stellarator prototype design, the Wendelstein 7-X.
Proxima Fusion is backed by the European Union, the German government, and venture capital. Proxima set out to design a commercial scale stellarator with a two-year timeline but achieved their goal within one year.
Dubbed Stellaris, the Proxima stellarator concept leverages stronger magnetic fields made possible using high-temperature superconducting (HTS) technology to build smaller stellarators without reducing energy output.
Using materials available in the existing supply chain ensures that the reactors can be built without waiting for a technology to become economically feasible and it brings the reality of fusion energy closer than before.
For publication, the Stellaris design has undergone detailed peer review and claims that it can overcome physics and engineering constraints through various simulations. The company is now ready to build a demonstrator plant called Alpha as early as 2031.
If all goes well, Proxima Fusion’s design could add power to our grids as early as the next decade.