Nuclear fusion breakthrough: British reactor sets new world record after releasing 69 megajoules of energy for five seconds – bringing world closer to ‘limitless clean energy’
After more than forty years, the British nuclear reactor is still setting records.
In the latest series of experiments, the Joint European Torus (JET), based in Culham, Oxfordshire, released a total of 69 megajoules of energy in five seconds.
While not a huge energy output, it is a world record and offers promise for a future of nuclear power to power people’s homes.
Built in the late 1970s, JET contains swirling plasma heated to 150 million Kelvin – ten times hotter than the center of the sun.
At such temperatures, hydrogen atoms fuse into helium, releasing sustainable energy that could put an end to fossil fuels.
Joint European Torus (JET, pictured) was built in 1978 on an industrial estate outside Oxford – and has now achieved a new world record by releasing a total of 69 megajoules of energy
JET started operations in 1983 but will now be dismantled after its scientific activities concluded at the end of December.
The British facility, which will reportedly cost £20-30 million a year to operate, is seen as a precursor to the $22.5 billion (£15.9 billion) International Thermonuclear Experimental Reactor (ITER) being built in France built.
“JET’s latest fusion experiment is a fitting swan song after all the groundbreaking work that has gone into the project since 1983,” said UK Secretary of State for Nuclear Energy and Networks Andrew Bowie.
‘We are closer to fusion energy than ever before thanks to the international team of scientists and engineers in Oxfordshire.’
JET’s new energy record was set with just 0.2 milligrams of fuel – about the same weight as a single grain of pollen.
But the resulting energy output (69 megajoules) is enough to heat the water and brew about 600 cups of tea.
It also beats its own previous record of 59 megajoules, set more than two years ago.
If it were to run continuously at 69 megajoules, it would be able to supply power to approximately 12,000 homes on a continuous basis.
JET was built as a research facility to demonstrate the promising potential of nuclear fusion to produce energy.
But it could be a precursor to nuclear fusion power plants around the world that deliver power directly to the grid and electricity to people’s homes.
Fusion power plants could reduce greenhouse gas emissions from the power generation sector by moving away from the use of fossil fuels such as coal and gas.
If nuclear fusion experiments can be applied on a much larger scale, reactors hotter than anything else in the solar system will produce limitless clean energy. Tokamak Energy is a privately held company based at the Culham Center for Fusion Energy in Oxfordshire
The UKAEA announced that the Joint European Torus (JET), the largest and most powerful operational reactor, called a tokamak, had produced a world record total of 59 megajoules of heat energy from fusion in a period of five seconds.
Pictured is an artist’s impression of the JET facility at the Culham Center for Fusion Energy, Oxfordshire
“JET has worked as close to power station conditions as is possible with current facilities,” said Sir Ian Chapman, CEO of the UK Atomic Energy Authority.
“Its legacy will be ubiquitous in all future power plants.
‘It plays a crucial role in bringing us closer to a safe and sustainable future.’
Like other fusion reactors, JET is a tokamak, a type of structure that uses powerful magnetic fields to confine ‘plasma’ in the shape of a doughnut.
Hydrogen gas in the vessel is heated to become the plasma, a soup of positively charged particles (ions) and negatively charged particles (electrons).
In the tokamak, the plasma is collected and pressurized by magnetic fields until the activated plasma particles begin to collide.
As the particles fuse into helium, enormous amounts of energy are released, mimicking the process that occurs naturally at the center of stars.
With a torus of about six meters in diameter, JET is not the largest nuclear fusion reactor in the world.
The Japanese reactor, named JT-60SA and recently switched on in Naka, north of Tokyo, is a six-story machine measuring 15 meters high and 13 meters wide.
Fusion power works by colliding heavy hydrogen atoms to form helium, releasing enormous amounts of energy, as occurs naturally in the centers of stars.
The JT-60SA, jointly built and operated by Europe and Japan, will be the largest fusion reactor in the world until the completion of ITER in France.
Other smaller reactors are being built and tested – including the ST40 in Oxfordshire, which is more compact and compact compared to other ‘doughnut-shaped’ reactors.
Fusion differs from fission (the technique currently used in nuclear power plants) because the former fuses two atomic nuclei together instead of splitting one (fission).
Unlike nuclear fission, fusion poses no risk of catastrophic nuclear accidents — such as the one at Fukushima, Japan, in 2011 — and produces far less radioactive waste than today’s power plants, its exponents say.