European scientists set a new record for the most energy generated from nuclear fusion, the latest breakthrough in a two-decade effort to produce power by harnessing the reaction that powers the sun.

UK-based JET (Joint European Torus) laboratory achieved the new world record for the amount of energy that can be extracted by squeezing together two forms of hydrogen, smashing their own record.

If nuclear fusion can be successfully recreated on Earth it holds the potential of virtually unlimited supplies of low-carbon, low-radiation energy. The experiments produced 59 megajoules of energy over five seconds (11 megawatts of power).

This is more than two times of what was achieved in similar tests in the year 1997. Considering that the energy output is only enough to boil about 60 kettles' of water, it’s not massive. But it’s significance lies in the fact that it validates design choices that were made for an even bigger fusion reactor now being constructed in France.

"The JET experiments put us a step closer to fusion power," said Dr Joe Milnes, the head of operations at the reactor lab. "We've demonstrated that we can create a mini star inside of our machine and hold it there for five seconds and get high performance, which really takes us into a new realm."

“These landmark results have taken us a huge step closer to conquering one of the biggest scientific and engineering challenges of them all,” said Ian Chapman, chief executive of the UK’s Atomic Energy Authority.

In half a century of experiments around the world scientists have been unable to generate more energy from a fusion reaction than what the power-intensive system consumes.

Unlike nuclear fission, when atoms are split, fusion does not produce significant radioactive waste. But the biggest challenge to make fusion commercial is how the reaction can be sustained and prevented from extinguishing.

JET and ITER are two of several large, publicly funded fusion projects around the world but private sector money has also been flowing into fusion energy start-ups. Total private sector financing had reached more than $3bn by the end of 2021 with some of the ventures aiming to deliver commercial power in the 2030s.

George Freeman, UK minister for science, research and innovation, said the UK was committed to helping fusion energy succeed. “We are determined to make sure we adopt it in our energy mix and make clear to the energy sector that this technology is coming.”