China's BEST Fusion Device Achieves Major Milestone with Dewar Base Installation

Key Component Installed for China's Fusion Reactor

HEFEI, China – The Burning Plasma Experimental Superconducting Tokamak (BEST), China's compact fusion experiment device, achieved a significant milestone on October 1, 2025, with the successful installation of its Dewar base. This development, taking place in Hefei, Anhui Province, marks a crucial step forward in the nation's pursuit of fusion power generation.

The Dewar base, described as the first key component, is integral to the BEST project, which aims to demonstrate the actual 'burning' of deuterium-tritium plasma. Fusion energy, often referred to as the 'ultimate energy source,' seeks to replicate the process that powers the sun, offering a clean and potentially limitless energy solution.

Technical Prowess Behind the Dewar Base

The newly installed Dewar base is a marvel of engineering, serving as the foundation for the entire BEST device. Huang Xiongyi, an associate researcher with the Chinese Academy of Sciences' Institute of Plasma Physics, stated that the base will eventually support over 6,000 tonnes of equipment. Weighing more than 400 tonnes and measuring approximately 18 meters in diameter and 5 meters in height, it represents the heaviest single component of BEST's main machine and the largest vacuum component ever produced in China's fusion research field.

Its development necessitated breakthroughs in several advanced technical areas, including:

• High-precision forming and welding
• Millimeter-scale deformation control
• Ultra-high vacuum sealing

These challenges were overcome, resulting in millimeter-level precision during installation. The Dewar itself functions like a giant high-vacuum thermos flask, essential for insulating the superconducting magnets that must operate at minus 269 degrees Celsius to confine plasma heated to over 100 million degrees.

Project Timeline and Future Outlook

The full-scale assembly of the BEST project commenced in May 2025. With the Dewar base now in place, other core components of the main machine will be gradually assembled. The BEST device is scheduled for completion by the end of 2027. According to the project team, BEST is poised to become the first device globally to verify and demonstrate nuclear fusion power generation on a practical scale, with an ambitious goal of lighting up the first light bulb using fusion-generated electricity by 2030.

Song Yuntao, the project's chief engineer from the Institute of Plasma Physics in Hefei, has affirmed that the team has 'fully mastered the core technologies, both scientifically and technically.' BEST is designed to achieve a fivefold energy gain, meaning it produces five times more output energy than the input, and represents an intermediate phase between China's earlier Experimental Advanced Superconducting Tokamak (EAST) and the future Chinese Fusion Engineering Test Reactor (CFETR).