The Princeton Plasma Physics Laboratory (PPPL) has developed a small, experimental nuclear fusion reactor, constructed largely with 3D-printed and off-the-shelf parts. This compact reactor—roughly the size of a kitchen table—uses a glass tube surrounded by 3D-printed nylon and nearly 10,000 rare-earth magnets to contain superheated plasma, the basis for generating fusion energy, much like the process powering stars.

This innovative design represents a significant reduction in cost and time compared to traditional fusion reactors; while similar reactors in Germany required two decades and $1.1 billion to construct, Princeton’s model was built within a year for only $640,000. The PPPL reactor is based on a “stellarator” design, using magnetic fields to stabilize plasma, and aims to release large amounts of clean energy by fusing atomic nuclei without the toxic waste produced by traditional fission reactors.

Nuclear fusion, while not yet commercially viable, is attracting attention as the tech industry seeks sustainable power solutions to support energy-intensive AI technologies. Big tech companies like Microsoft, Amazon, and Google are already exploring nuclear energy alternatives to power data centers, though most investments so far rely on fission, which still generates radioactive waste. Fusion, by contrast, has the potential to produce vast, nearly limitless energy without this waste, promising a safer, cleaner alternative.

To bring fusion closer to practical use, the U.S. government has partnered with Type One Energy, a company specializing in stellarator fusion reactors, to build a fusion pilot plant in Tennessee. Expected to be operational by 2029, this plant will focus on validating fusion technology at scale rather than immediate energy production. Although commercial fusion remains distant, Princeton’s low-cost, 3D-printed fusion reactor symbolizes a promising step toward a zero-carbon, high-energy future.

Filed in Green. Read more about 3D Printing, Nuclear and Sustainability.