The Princeton Plasma Physics Laboratory (PPPL) has achieved a groundbreaking feat: creating a compact fusion reactor using 3D-printed parts and off-the-shelf materials, all small enough to fit on a kitchen table. This deceptively simple device—a glass vacuum tube surrounded by 3D-printed nylon and thousands of magnets—contains the key to replicating the power of the stars, potentially leading to a future of abundant, clean energy.

The story, shared by IEEE Spectrum, highlights how PPPL’s reactor could change the fusion landscape. While fusion reactors have existed for years, they’re typically massive and costly. Germany’s Wendelstein 7-X, an experimental stellarator, took two decades and $1.1 billion to build. In contrast, PPPL’s smaller-scale reactor prototype is an affordable proof of concept, demonstrating that the principles of fusion can be achieved with minimal resources and compact designs.

The PPPL fusion reactor is based on a stellarator design—a device that uses magnetic fields to contain plasma. The vacuum tube within this prototype houses 9,920 rare-earth magnets, designed to guide superheated plasma as atoms collide and their nuclei fuse, releasing vast energy. Unlike nuclear fission, which splits atoms and generates radioactive waste, fusion offers a safer, cleaner process with no risk of meltdowns and no waste that could be weaponized.

With AI and tech advancements accelerating, the demand for high energy levels has never been higher, and current sources are struggling to meet these demands sustainably. As coal and other traditional sources are phased out, tech giants are investing heavily in nuclear power. Microsoft is considering nuclear options for its AI data centers, and Amazon has committed $500 million toward modular nuclear reactors. However, these smaller reactors, while less cumbersome than traditional nuclear plants, still rely on fission and produce radioactive waste.

Fusion, in contrast, promises a nearly limitless energy source without these downsides. As a clean alternative, fusion has attracted attention and funding from major tech figures like Bill Gates, whose Breakthrough Energy fund backs Type One Energy, a private company also developing stellarator-style reactors.

PPPL’s tabletop fusion reactor is a significant step, but fusion as a mainstream energy source remains distant. The U.S. government is collaborating with Type One to build a stellarator-based fusion plant in Tennessee, projected to be operational by 2029. While it won’t initially supply commercial power, it’s expected to validate critical features of fusion reactors, helping pave the way for eventual power generation.

PPPL’s achievement fuels hope that fusion might one day power homes and industries safely and sustainably. For now, it stands as a testament to innovation, and as this technology matures, it could lead us into a future where compact fusion reactors play a crucial role in the energy landscape.

By Impact Lab