KSTAR Reaches New Record in High-Temperature Operation with Tungsten Diverter

The Korea Tokamak Superconducting Advanced Research (KSTAR) fusion reactor, operated by the Korean Fusion Energy Institute (KFE), has achieved a new record in high-temperature operation. During testing from December 2023 to February 2024, the reactor sustained a temperature of 100 million degrees Celsius for an unprecedented 48 seconds. This milestone is a significant leap forward in the development of magnetic confinement fusion energy technology.

In addition to reaching this impressive temperature, the KSTAR reactor also maintained high limit mode (H mode) for over 100 seconds. H-mode is a crucial operating mode that allows for stable plasma behavior during fusion reactions. By simulating the production of light and heat from stars through nuclear fusion, KSTAR’s operation demonstrates the potential for clean and sustainable energy sources in the future.

A major contributor to KSTAR’s success was the implementation of a new tungsten diverter at the bottom of its vacuum tank. The diverter helps expel exhaust gases and impurities while withstanding high surface heat loads. By switching from carbon to tungsten in the diverter, KFE researchers observed significant improvements in temperature management and operational efficiency, enabling longer periods of H-mode operation.

The successful use of tungsten in KSTAR could have valuable implications for other fusion energy projects around the world, including ITER, an international collaboration working towards creating a plasma state by 2025 and beginning operations by 2035. Tungsten will also be used as part of ITER’s diverter system, further highlighting the potential impact of KFE’s advancements on global fusion research efforts.

Overall, this achievement marks a significant step forward in magnetic confinement fusion technology and opens up exciting possibilities for future developments in clean energy solutions.