Back in Dec 2020 we wrote about the Korea Superconducting Tokamak Advanced Research (KSTAR) magnetic fusion reactor’s record-breaking feat of heating hydrogen plasma up to 100 megakelvins for 20 seconds. Last month it broke its own record, extending that to 30 seconds. The target of the program is 300 seconds by 2026. There is a bit of competition going, as KSTAR’s Chinese partner in the International Thermonuclear Experimental Reactor (ITER), the Experimental Advanced Superconducting Tokamak (EAST) did a run a week later reaching 70 million degrees for 1056 seconds. It should be noted that KSTAR is reaching these temperatures by heating ions in the plasma, while EAST takes a different approach acting on the electrons.
The news reports seem to be using Celsius and Kelvins interchangeably, but at millions of degrees, that’s probably much smaller than measurement error. These various milestones are but stepping stones along the path to create a demonstration large fusion reactor, the goal of the global ITER mega-project. Currently China, the EU including Switzerland and the UK, India, Japan, Russia, South Korea, and the United States are members of ITER, and Australia, Canada, Kazakhstan, and Thailand are participants. The ITER demonstration reactor is being constructed at the Cadarache facility located 60 km northeast of Marseille, France, and is on track for commissioning phase to begin in 2025, going operational ten years later.
The Korea Superconducting Tokamak Advanced Research (KSTAR) magnetic fusion reactor claimed a new record last month — containing hydrogen plasma at 100 megakelvins for 20 seconds. For reference, the core temperature of the Earth’s Sun is a mere 15 megakelvins, although to be fair, it has been in operation quite a bit longer than 20 seconds.
South Korea is a member of the International Thermonuclear Experimental Reactor (ITER) team, a worldwide project researching the science and engineering of nuclear fusion. One of their contributions to the effort is the KSTAR facility, located in the city of Daejeon in the middle of the country (about 150 km south of Seoul).
It is a tokamak-style fusion research reactor using superconducting magnets to generate a magnetic flux density of 3.5 teslas and a plasma current of 2 megaamperes. These conditions are used to confine and maintain the plasma in what’s called the high-confinement mode, the conditions currently favored for fusion reactor designs. Since it went into operation in 2008, it has been creating increasingly longer and hotter “pulses” of plasma.
For all the impressive numbers, the toroidal reactor itself is not that huge. Its major diameter is only 3.6 meters with a minor diameter of 1 meter. What makes the facility so large is all the supporting equipment. Check out the video below — we really like the techniques they use in this virtual tour to highlight key components of the installation.
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