ABINGDON, United Kingdom (AFP) – British scientists announced on Wednesday that they had broken a previous record for fusion power production, hailing it as a “milestone” on the road to clean and cheap energy and a colder planet.
Nuclear fusion is the same process the sun uses to generate heat. Proponents believe it could one day help fight climate change by providing an abundant, safe and green source of energy.
A team from the Joint European Torus (JET) facility near Oxford, central England, generated 59 megajoules of energy for five seconds in an experiment in December, more than double that of a record from 1997, the UK Atomic Energy Authority said.
That’s about the power needed to power 35,000 homes for the same period of time, five seconds, said JET chief operating officer Joe Milnes.
The results “are the world’s clearest demonstration of the potential of fusion power to deliver secure and sustainable low-carbon energy,” the UKAEA said.
The doughnut-shaped machine used for the experiments is called a tokamak, and the JET site is the largest operational in the world.
Britain’s Prince Charles, Prince of Wales (right) meets staff at the Joint European Torus (JET) control room during a visit to the UK Atomic Energy Authority in Culham, near Abingdon, on January 31, 2022. (ADRIAN DENNIS / POOL / AFP)
Inside, just 0.1 milligrams each of deuterium and tritium – both are isotopes of hydrogen, deuterium also called heavy hydrogen – are heated to temperatures 10 times hotter than the center of the sun to create plasma.
This is held in place with magnets as it spins, fuses and releases enormous energy in the form of heat.
Fusion is inherently safe in that it cannot start a runaway process.
Deuterium is freely available in seawater, while tritium can be harvested as a byproduct of nuclear fission.
Pound for pound (gram for gram), it releases nearly four million times more energy than burning coal, oil or gas, and the only waste product is helium.
Reagan-Gorbachev merger
Results announced Wednesday demonstrated the ability to create fusion for five seconds, because longer than that would cause JET’s copper-wire magnets to overheat.
A larger, more advanced version of JET is currently being built in the south of France, called ITER, where data from Oxford will prove vital when the site comes online, possibly as soon as 2025.
ITER will be equipped with superconducting electromagnets that will allow the process to continue for longer, hopefully over 300 seconds.
Around 350 scientists from EU countries as well as Britain, Switzerland and Ukraine – and others from around the world – take part in JET experiments each year.
JET will soon hand over the fusion baton to ITER, which is about 80% complete, Milnes said.
“If this is successful, as we now believe will yield the results we had on JET, we can develop power plant designs in parallel…we are probably halfway” to a viable fusion, said he declared.

Prince Charles (left) views equipment in the UK Atomic Energy Authority’s remote manipulation control room in Culham, near Abingdon, on January 31, 2022. (ADRIAN DENNIS / POOL / AFP)
If all goes well at ITER, a prototype fusion power plant could be ready by 2050.
International cooperation on fusion energy has always been close because, unlike nuclear fission used in nuclear power plants, the technology cannot be weaponized.
The France-based megaproject also involves China, the EU, India, Japan, South Korea, Russia and the United States.
Tim Luce, head of science and operations at ITER, said the project emerged in the 1980s following discussions on nuclear disarmament between US President Ronald Reagan and Soviet leader Mikhail Gorbachev.
“And the only thing they agreed on was to use the merger as cooperation,” he told AFP.
“One way or another, the merger had the scientific panache to bring disparate government entities together and choose to work on it together.”
Although dozens of tokamaks have been built since their first invention in Soviet Russia in the 1950s, none have yet succeeded in producing more energy than is put in.
The latest results use about three times the amount of energy produced.
Ian Fells, emeritus professor of energy conversion at Newcastle University, said Wednesday’s result was a “landmark in fusion research”.
“It is now up to the engineers to translate this into carbon-free electricity and mitigate the problem of climate change,” added Fells, who is not involved in the project.