By, Arizona New Times
South Korea has achieved a major milestone in the quest for nuclear fusion, the process that powers the Sun and other stars. Scientists in South Korea’s Korea Superconducting Tokamak Advanced Research (KSTAR) facility (Korea Institute of Fusion Energy) have managed to sustain a nuclear fusion reaction running at temperatures in excess of 100 million°C for 30 seconds for the first time . This is a significant improvement from the previous record of 20 seconds set by the same facility in 2020.
Nuclear fusion is the process of fusing two lighter atoms into a heavier one, releasing a huge amount of energy in the process. Unlike nuclear fission, which splits atoms and produces radioactive waste, nuclear fusion is clean and virtually limitless. However, achieving and maintaining nuclear fusion is extremely difficult, as it requires extremely high temperatures and pressures to overcome the natural repulsion between the positively charged nuclei of the atoms.
The KSTAR facility uses a device called a tokamak, which is a doughnut-shaped chamber that contains a plasma of hydrogen isotopes. The plasma is heated and compressed by powerful magnetic fields, creating the conditions for fusion to occur. The goal is to reach a state of ignition, where the fusion reaction becomes self-sustaining and produces more energy than it consumes.
The KSTAR team reported that they have finally been able to achieve a net energy gain when carrying out a nuclear fusion experiment. This means that the amount of energy produced by the fusion reaction was greater than the amount of energy required to heat and confine the plasma. This is a crucial step towards achieving ignition and making nuclear fusion a viable source of energy.
The KSTAR team also said that they have successfully tested a new mode of plasma operation, called the advanced divertor. This is a system that controls the heat and particles that escape from the plasma and protects the walls of the tokamak from damage. The advanced divertor allows the plasma to operate at higher densities and pressures, which are essential for achieving ignition.
The KSTAR team’s achievement has been hailed as a breakthrough in the field of nuclear fusion and a major step towards the ‘holy grail’ of creating a mini Sun on Earth . The team plans to extend the duration of the high-temperature plasma to 300 seconds by 2025, which would bring them closer to the goal of continuous operation.
The KSTAR facility is part of the International Thermonuclear Experimental Reactor (ITER) project, which is a global collaboration of 35 countries to build the world’s largest and most powerful tokamak in France. The ITER project aims to demonstrate the feasibility of nuclear fusion as a large-scale and carbon-free source of energy. The ITER tokamak is expected to start its first plasma experiments in 2025 and achieve full fusion power by 2035.