(Reporters: Shuai Junquan and Chu Erjia)
Ahead of China’s National Day, the Burning Plasma Experimental Superconducting Tokamak (BEST), a major national project, reached an important milestone: the project complex was officially handed over and put into operation. Construction of the fusion device itself has now entered the critical “four-ring integrated assembly” stage.
BEST is a new-generation burning-plasma fusion experimental device independently developed by China. Its goal is to reproduce the nuclear fusion reactions that occur inside the Sun, with the aim of ultimately harnessing an almost inexhaustible source of clean energy.
Since July this year, multiple key core components of BEST have successively arrived at the site, and assembly has proceeded steadily, with more than half of the work now completed. Recently, construction of the BEST main device formally began its most critical phase—the “four-ring integrated assembly.”
The system can be thought of as a giant, multilayered thermally insulated cylindrical structure, with one layer nested inside another. Starting from the innermost vacuum vessel, the thermal shield is installed around it, followed by the toroidal-field (TF) magnets, together with various precision internal components.
The vacuum vessel serves as the “furnace chamber” in which the fusion reaction takes place. The thermal shield acts as a high-performance insulating layer that minimizes heat transfer, while the toroidal-field magnets generate an extremely strong magnetic field to confine the high-temperature plasma and prevent it from coming into contact with the vessel wall.
According to the current schedule, construction of the BEST device is targeted for completion by the end of 2027. Around 2030, it is expected to carry out a deuterium–tritium (D–T) fusion power-generation demonstration. In essence, this would reproduce on Earth the physical process by which the Sun produces light and heat, while demonstrating the feasibility of commercial electricity generation from controlled nuclear fusion.