South Korea’s artificial Sun ran for 102 seconds and it could change the future of energy

The South Korean artificial sun, which goes by the name KSTAR (Korea Superconducting Tokamak Advanced Research), has made an important scientific discovery concerning nuclear fusion by being able to sustain plasma in high-confinement mode for a period of 102 seconds while simultaneously managing to keep plasma temperature at 100 million degrees centigrade for 48 seconds. This development by the Korea Institute of Fusion Energy (KFE) is another move towards achieving clean fusion energy, whose ability to generate unlimited amounts of electricity with little to no carbon emission is promising. Scientists employed enhanced tungsten divertor technology to ensure the stability of plasma.Nuclear fusion has been considered the ideal source of energy for decades now. This process is unlike traditional fission energy production, where atoms are split into smaller parts to release energy. Instead, it involves combining light atomic nuclei and generating massive amounts of energy in the process. The same applies in all the stars we observe in space today.KSTAR from South Korea has risen to be among the best fusion reactors in the world today. In the 2023-2024 plasma campaign conducted on this reactor, scientists managed to sustain the plasma at 100 million degrees Celsius ion temperature for 48 seconds. This was preceded by a feat of sustaining H-mode operations for 102 seconds, surpassing past KSTAR operational achievements in the area according to the Korea Institute of Fusion Energy.Creating fusion on earth is significantly harder than it sounds because in order to create a fusion reaction in the Sun, a great amount of gravitational pressure must be exerted. Scientists need to replace the absence of that pressure by creating tremendous amounts of heat.When the temperature reaches 100 million degrees Celsius, plasma heats up sufficiently so that hydrogen isotopes have a chance to combine due to the loss of their repelling nature. However, there are no substances on earth that could hold the extreme amount of heat without being damaged.KSTAR applies superconducting magnetic forces to trap plasma within a doughnut-shaped vessel called a tokamak. It is important not just to create heat, but also maintain it for some time. Each additional second of operation becomes very beneficial for further research.One of the key factors behind the recent success of KSTAR lies in the use of the newly installed tungsten divertor. This important element is located on the bottom side of the tokamak and withstands high heat and exhaust plasma.As reported by the Korea Institute of Fusion Energy, the earlier installed carbon divertors were already at their limits when experiments grew to be more extensive and heated. Tungsten has a reputation for its extraordinary ability to resist heat, which allows the reactor to take on much higher temperatures in the process of fusion reactions.As stated in the official press release of KFE, scientists used tungsten precisely because it would provide conditions necessary to conduct future long pulses of plasma for the achievement of the goal of sustaining plasma at 100 million degrees for 300 seconds.Even with this breakthrough, the fusion scientists are being very modest. Creating plasma for minutes or even hours, producing more power than that consumed by the fusion reactor, is undoubtedly one of science’s biggest engineering tasks to date.Nonetheless, this progress by the KSTAR is a clear example of the rapid advancement taking place in the field of fusion technology. Scientists from the KSTAR Research Center have already planned to operate for 300 seconds with temperatures higher than 100 million degrees centigrade. This, according to the director of KSTAR Research Center, Dr Si-Woo Yoon, was accomplished via intensive hardware testing and proper planning of campaigns.If future research follows through and progresses from there, fusion energy may someday come to be an environmentally friendly alternative that can run non-stop and is free of carbon emissions that come along with fossil fuels.In the meantime, KSTAR's success of reaching 102 seconds in no way violates the laws of nature. Instead, it shows that scientists are gradually learning how to operate just by the edge of those laws.