China’s BEST Tokamak Is Being Assembled in Hefei, With a 2027 Target

China’s Burning Plasma Experimental Superconducting Tokamak (BEST) has moved from construction of its Hefei complex into assembly of the tokamak itself. As of early October 2026, the complex had been handed over, while reports described the machine as entering a demanding, layer-by-layer assembly phase. The end-of-2027 target is a construction milestone; the project’s hoped-for electricity demonstration around 2030 is a separate, later goal.2436

What has been completed—and what has not

The project complex is in use, and key components have arrived at the site. The main machine is still being assembled, including its vessel, shielding and magnetic components.24 So BEST is not yet an operating fusion experiment, and the handover of the campus does not mean the reactor is complete.

The schedule is not described identically across available reporting. Some accounts give an end-of-2027 completion target, while another project summary says BEST aims to be largely complete by 2028.114 These are reported plans, not confirmation that the facility will meet either date.

BEST’s fusion goals—and what Q means

BEST is designed to study deuterium–tritium (D–T) burning plasma and validate fusion-engineering technologies. One technical account gives a target of 20–200 megawatts of fusion output and a gain factor, Q, of about 1. Other descriptions frame the ambition as achieving net fusion power gain.91317

Those descriptions should not be treated as evidence of a result. Q compares fusion power produced with the power delivered to the plasma; Q around 1 means those amounts are roughly equal, not that the entire facility produces more electricity than it consumes. Net electricity for the grid is a further milestone. The available reports do not establish that BEST has achieved fusion gain or generated electricity.

How EAST and CRAFT fit into the path

BEST builds on research experience at Hefei’s EAST tokamak, which has sustained high-confinement plasma for a reported 1,066 seconds. That record demonstrates long-duration plasma control; BEST has a different task—investigating D–T burning plasma and fusion-power engineering.259

CRAFT contributes to the wider engineering effort. A major superconducting magnet associated with the CRAFT testing program passed testing, addressing an important component challenge for fusion systems. A magnet test is an engineering milestone, not a fusion-power demonstration by BEST.3442

China has also launched an international burning-plasma research program that opens major research platforms, including BEST, to scientists for collaboration.18 That expands research access, but it does not change the facility’s construction status or demonstrate performance.

From BEST to electricity: the remaining milestones

Reports describe an electricity-generation demonstration around 2030 as a goal for the project.1735 That would be distinct from completing assembly, operating the machine, or showing fusion gain. A planned Chinese engineering-demonstration reactor, often identified as CFETR, is described as a later step beyond BEST; the sources do not establish a firm date for a commercial power plant.912

The practical takeaway is that BEST is an experimental bridge from plasma research toward fusion engineering. The complex handover and ongoing assembly mark real progress, but the central tests—burning-plasma performance, fusion gain and electricity generation—remain ahead.