Another success, at least the fifth in the past two years, on a path that focuses on nuclear fusion energy, i.e. mimicking the processes taking place on the Sun, is this next step forward The KStar reactor, also called the “Artificial Sun”, operated by South Korea’s Nuclear Fusion Institute, Kfe.
If the previous records between Europe and the United States have been about the amount of energy produced, this latest result is about the ability of Korea’s magnetic containment reactor to maintain the incredibly high temperatures that the plasma must reach for fusion for long periods of time. reactions take place nuclear. After recent modifications, KStar actually managed to sustain a plasma that reached a temperature of 100 million degrees for 48 seconds. In the high retention mode, in which the plasma has a longer energy retention time, a lifetime of 102 seconds was achieved.
“We will do our best to ensure the availability of basic technologies for both Iter and, in the future, Demo,” said KFE President Suk Jae Yoo, referring to the future experimental fusion reactors, the first under construction in France at Cadarache and the second destined to become his successor. The difference is in the new material, tungsten, which replaced the divertors, i.e. the inner part of the doughnut-shaped structure (tokamak), through which the plasma is deflected. The material is the same as in the Iter reactor. “This is an important result,” said Alberto Loarte, head of science at Iter. “It is essential to have a material resistant to contact with the very high temperatures that the plasma reaches inside the reactor – he added – and tungsten is also the material that will be used for the demo.” Tungsten is also the material of choice for the DTT machine, the Divertor Tokamak test under construction at the Enea research center in Frascati, which should be operational around 2029. “The DTT will have an entire wall in tungsten and we will be able to study the performance in energy flows with it’s close to 20 megawatts per square meter,” said Paola Batistoni, head of fusion energy development at Enea. “The divers are the most critical part of the reactor and this material allows pulses to be emitted for longer periods of time,” he added. An interesting fact is that the KStar reactor of the latest generation “enables operation in conditions that are increasingly approaching the conditions of a power plant”.
However, the great innovation in fusion research is that this ambitious field of research no longer sees only big machines like Iter, Demo, Dtt or KStar among the protagonists: “Right now, there is a lot of interest in mergers from startups that raised more than $6 billion from private investors to build new machines in the 2030s.“, said Batistoni. Fusion is increasingly clearly a big bet on the clean energy of the future: “it can represent – the expert concluded – the solution to the energy transition.” It is a truly safe technology, it does not produce long-term waste or CO2 and it is rare because it can provide us with a continuous source of energy .”