Last month, the Korea Superconducting Tokamak Advanced Research (KSTAR) device, a nuclear fusion reactor known as an “artificial sun,” broke the world record by holding a plasma for an incredible 20 seconds at an ion temperature of more than 100 million degrees Celsius (180 million degrees Fahrenheit), which is one of the core conditions for nuclear fusion of such a device.
KSTAR’s progress has been astounding. It first reached 100 million degrees Celsius in 2018, but only for 1.5 seconds. In 2019 this was extended to 8 seconds. This has now more than doubled. No other device that has been able to produce plasma this hot (or hotter) has been able to hold it for more than 10 seconds.
The record-breaking performance was possible thanks to a newly developed Internal Transport Barrier Mode. The researchers think they can achieve 300 seconds over the next five years with a higher ion temperature than here. A crucial goal in the future development of commercial nuclear fusion reactors.
“The technologies required for long-term operations of 100 million degrees of plasma are key to the realization of fusion energy,” said Si-Woo Yoon, director of the KSTAR Research Center at the Korea Institute of Fusion Energy, in a statement. “[T]KSTAR’s success in maintaining the plasma at high temperature for 20 seconds will be a major turning point in the race to secure the technologies for the long-term high-performance plasma control, an essential part of a commercial fusion reactor in the future . “
This KSTAR run started in August and lasted until December 10th. The team conducted a total of 110 plasma experiments to test the capabilities of the device, as well as methods and techniques for injecting and stabilizing the plasma. The experiments were carried out in collaboration with national and international partners.
South Korea is one of the members of ITER (originally the International Thermonuclear Experimental Reactor), the engineering mega project that will be the largest nuclear fusion reactors ever. The aim is to demonstrate that it is possible to build a device that can release more energy through nuclear fusion (in a controlled manner) than is necessary to create the condition for the fusion of light atoms.
The experiments being conducted with KSTAR are critical to informing the development of ITER, which should be operational by 2025. The results of the KSTAR run in 2020 are expected to be presented at the IAEA Fusion Energy Conference in May 2021.
While the joke is that nuclear fusion is always 20 years away, developments like this one from the past decade really show how far this field has come.