So-Called “Artificial Sun” May Be Possible by 2026

( — The Korea Institute of Fusion Energy announced last month that its artificial sun, KSTAR, had completed diverter upgrades that could allow it to sustain high-ion temperatures of over 100 million degrees Celcius for longer periods, Gizmodo reported.

KSTAR is described as an artificial sun because it uses nuclear fusion, the same reaction that powers the Sun. It was completed in 2007 and achieved its first plasma, the electrically charged gases that are brought to super-high temperatures, the following year.

The KSTAR, like the ITER experimental reactor in France, is a tokamak, a donut-shaped device that uses plasma for nuclear fusion.

KSTAR deploys a diverter that is placed at the base of the tokamak. The diverter is a plasma-facing component that manages waste gas exhaust and impurities in the reactor and is capable of withstanding the internal surface heat.

KSTAR can currently sustain plasma operations for about half a minute. However, scientists believe that with the installation of the new tungsten diverter, by the end of 2026, plasma operations can be sustained for periods of 300 seconds.

Originally, KSTAR used a carbon diverter. However, in 2018, scientists began developing a tungsten diverter for the tokamak since tungsten has a higher melting point than carbon, which would improve the heat flux limit of the KSTAR reactor two-fold, according to a news released from Korea’s National Research Council of Science and Technology.

The prototype of the new tungsten diverter was completed in 2021, with installation finished in 2022.

French scientists also employed tungsten in the ITER reactor.

ITER’s first plasma is expected next year, with the reactor’s first fusion slated for 2035.

ITER is far larger than KSTAR, and its projected timeline has been delayed due to its ballooning cost. According to Scientific American, the costs for ITER went from €5 billion, or about $5.5 billion USD, in 2006 to more than €20 billion, or $21.8 billion USD.

Copyright 2024,