Limitless, Cheap Clean Energy: China launches Its “Artificial Sun”

China is about to start operation on its “artificial sun“—a nuclear fusion device that produces energy by replicating the reactions that take place at the center of the sun. If successful, the device could edge scientists closer to achieving the ultimate goal of nuclear fusion: near limitless, cheap clean energy.

The device, called HL-2M Tokamak, is part of the nation’s Experimental Advanced Superconducting Tokamak project, which has been running since 2006. In March, an official from the China National Nuclear Corporation announced it would complete building HL-2M by the end of the year.

The coil system was installed in June and since then, work on HL-2M has gone “smoothly,” the Xinhua News Agency reported in November.

Duan Xuru, head of the Southwestern Institute of Physics, which is part of the corporation, announced the device will become operational in 2020 at the 2019 China Fusion Energy Conference, the state news agency said. He told attendees how the new device will achieve temperatures of over 200 million degrees Celsius. That’s about 13 times hotter than the center of the sun. Previous devices developed for the artificial sun experiment reached 100 million degrees Celsius, a breakthrough that was announced in November last year.

Nuclear fusion is the reaction that powers the sun. It involves fusing two lighter atomic nuclei to form a heavier nucleus—a reaction that releases a huge amount of energy. On the sun, where core temperatures reach about 15 million degrees Celsius, hydrogen nuclei combine to form helium.

To recreate this on Earth, scientists must heat the fuel—types of hydrogen—to temperatures over 100 million degrees Celsius. At this point, the fuel becomes a plasma. This extremely hot plasma must be confined and one method scientists have been developing is a donut shaped device called a tokamak. This uses magnetic fields to try to stabilize the plasma so reactions can take place and energy be released. However, plasma is prone to producing bursts. If these touch the reactor wall it can damage the device.