World's largest superconducting magnet completed in China

The Institute of Plasma Physics at the Chinese Academy of Sciences announced on Saturday a major milestone in the pursuit of limitless clean energy.

Two key superconducting magnets for a fusion reactor, developed under one the nation's "artificial sun" projects, have successfully passed rigorous development approval and full-parameter testing, achieving 100% domestic production.

The centerpiece of this announcement is the Toroidal Field (TF) superconducting magnet, which has officially become the largest of its kind ever constructed for a fusion device.

It measures 21 meters in length, 12 meters in width and 3.3 meters in height, with a total weight of 582 tonnes. By comparison, it is 1.3 times the volume of the ITER TF magnets and stores three times more energy.

The toroidal field magnet is a critical component of a tokamak fusion reactor, responsible for generating the powerful magnetic fields that confine plasma heated to over 100 million degrees Celsius.

The project required six years of dedicated design, research and testing to complete, yielding 47 authorized patents and 14 established technical standards.

Concurrently, a high-temperature superconducting central solenoid coil also passed its full-load testing.

Operating at a stable current of 60 kiloamperes with an energy storage of 6.03 megajoules, its performance indicators have reached world-leading levels. The central solenoid plays a vital role in inducing and driving the plasma current and adjusting its shape.

Both magnet systems have achieved full localization of their core technologies, a move that significantly reduces reliance on foreign supply chains and underscores China's growing independent research and manufacturing capabilities.

The breakthrough marks a significant step forward for one of China's domestic fusion reactor programs, known as CRAFT (Comprehensive Research Facility for Fusion Technology).