Nuclear fusion breakthrough as reactor runs seven times hotter than the Sun for 30 seconds

‘Artificial sun’ achieves milestone towards near-limitless clean energy.

Scientists in South Korea have managed to sustain a nuclear fusion reaction running at temperatures in excess of 100 million°C – nearly seven times hotter than the core of the Sun – for 30 seconds for the first time.

It marks an important advance in achieving viable fusion power, which promises near-limitless clean energy by mimicking the natural reactions occurring within the Sun.

A team from Seoul National University and the Korea Institute of Fusion Energy experimented with the reactor at the Korea Superconducting Tokamak Advanced Research (KSTAR), managing to achieve an improved technique for containing the plasma at the core of the reactor.

The “artificial sun” is one of several around the world that form the culmination of decades of research into the technology, which essentially merge atomic nuclei found in stars to generate vast amounts of energy that can be transformed into electricity.

A similar facility in China was able to run at a slightly lower temperature for more than 17 minutes last year. At 70 million degrees Celsius, the plasma was still five times hotter than the actual Sun.

The process has been hailed as the “holy grail” of clean energy, as it requires no fossil fuels and leaves behind no hazardous waste unlike current nuclear energy production methods.

“We usually say that fusion energy is a dream energy source – it is almost limitless, with low emission of greenhouse gases and no high-level radioactive waste – [but the latest breakthrough] means fusion is not a dream,” said Yoo Suk-jae, president of the Korea Institute of Fusion Energy.

At the start of the year, the Korea Institute of Fusion Energy set a goal of achieving plasma temperatures exceeding 100 million degrees for 50 seconds by the end of 2022, with a final target of 300 seconds by 2026.

“This is not the end of the story, we must move on to 300 seconds – 300 is the minimum time frame to demonstrate steady-state operations, then this plasma can work forever,” said KSTAR director Yoon Si-woo.

“If we can’t achieve that, we have to do something else.”

A study detailing the research, titled ‘A sustained high-temperature fusion plasma regime facilitated by fast ions’, was published in the scientific journal Nature this week.