Stellarator Fusion Reactor Wendelstein X-2 Achieves 17-Minute Steady-State Operation: A Key Milestone for Commercial Fusion

17 Minutes of Fusion Light

In February 2029, Germany's Max Planck Institute for Plasma Physics announced that its next-generation stellarator fusion reactor Wendelstein X-2 achieved 17 minutes of steady-state plasma operation in its latest experimental round, with plasma temperature reaching 120 million degrees, breaking the world record for fusion steady-state operation.

Wendelstein X-2 is an upgrade from X-1, with core improvements in superconducting magnet system precision. Stellarators confine plasma through external coils generating complex three-dimensional helical magnetic fields, requiring no plasma current like tokamaks, making indefinite steady-state operation theoretically possible. X-2's magnet system comprises 36 superconducting coils weighing over 800 tons, with magnetic field precision reaching one-millionth accuracy.

During the 17-minute run, X-2's plasma density and temperature remained highly stable. Neutron detectors recorded sustained deuterium-tritium fusion reaction signals. While energy produced still fell below the input energy needed to maintain the magnetic field, the energy gain factor Q value improved from X-1's 0.05 to 0.15.

Institute director Thomas Klinger stated that X-2's results prove the engineering viability of the stellarator approach. The next step plans to initiate X-3 design work in 2030, targeting Q values above 1 — where output energy exceeds input energy, achieving net energy gain.