China's "Artificial Sun" BEST Campus Delivered and Commissioned, Controlled Nuclear Fusion Accelerates Toward Engineering Demonstration

On October 1, the campus of the national major project Compact Fusion Energy Experimental Device (Burning plasma Experimental Superconducting Tokamak, BEST) was officially delivered and commissioned, and the main machine simultaneously entered the core assembly stage of the "four-ring set." The device is located in Hefei, Anhui, led in design by the Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), and constructed by Fusion New Energy (Anhui) Co., Ltd. It is China's independently developed new-generation fusion burning experimental device.

BEST aims to simulate solar nuclear fusion and fill the engineering gap between experimental reactors and demonstration reactors. The so-called "four-ring set" is the most critical challenging task in the construction of the main machine, which, from the inside out, sequentially completes the installation of the vacuum vessel, cold screen, toroidal field magnets, and internal precision components. The vacuum vessel is the "furnace chamber" of the fusion reaction, the cold screen is used for thermal insulation, and the toroidal field magnets generate an ultra-strong magnetic field to confine high-temperature plasma. Recently, 8 batch-produced toroidal field (Toroidal Field, TF) coil cases completed manufacturing and final assembly and were shipped, breaking through key technologies such as ultra-low-temperature high-strength and high-toughness materials, temperature-controlled forging of thick and large forgings, and high-nitrogen stainless steel welding.

According to the plan, BEST strives to complete overall construction by the end of 2027 and conduct a deuterium-tritium fusion power generation demonstration around 2030. The device is designed as a compact high-field superconducting tokamak with a major radius of 3.6 meters, a minor radius of 1.1 meters, and a toroidal magnetic field strength of 6.15 tesla, equipped with 50 megawatts of auxiliary heating power. The goal is to achieve a fusion gain Q≥1 by the end of 2030 and extend the operating time to more than 1000 seconds, so as to verify technologies such as the tritium fuel cycle, high-power heating, and remote maintenance for the future China Fusion Engineering Demonstration Reactor (CFEDR).

The international fusion field has paid great attention to this. In September 2026, a delegation from the Institute of Plasma Physics introduced BEST's progress at the 34th Symposium on Fusion Technology (SOFT) to more than 1,200 representatives from 29 countries. The Economist pointed out that China is advancing rapidly in the field of nuclear fusion by combining planning, funding, and supply chains. Overseas scientific research institutions and energy media generally regard BEST as an important landmark project in the global fusion race.

It is reported that the delivery of the BEST campus and the tackling of key challenges in the main machine mean that China's controlled nuclear fusion is accelerating from experimental verification to engineering demonstration. If subsequent construction and commissioning proceed according to schedule, the device will enhance China's position in the commercialization competition of fusion energy and also provide key engineering data for the ultimate solution of global clean energy.