After more than 40 years, the British nuclear reactor continues to break records.
In its latest round of experiments, the Joint European Torus (JET), located in Culham, Oxfordshire, released a total of 69 megajoules of energy in five seconds.
Although it is not a huge energy production, it is a world record and offers promise for a future of nuclear energy to power people’s homes.
JET, which was built in the late 1970s, contains rotating plasma heated to 150 million Kelvin, 10 times hotter than the center of the sun.
At such temperatures, hydrogen atoms fuse into helium, releasing sustainable energy in the process that could put an end to fossil fuels.
The Joint European Torus (JET, pictured) was built on an industrial estate outside Oxford in 1978 and has now achieved a new world record by releasing a total of 69 megajoules of energy.
JET began operation in 1983, but will now be decommissioned, having concluded its scientific operations at the end of December.
The British facility, which is said to cost between £20m and £30m a year to operate, is seen as a predecessor to the $22.5bn (£15.9bn) International Thermonuclear Experimental Reactor (ITER) being built in France.
“JET’s latest fusion experiment is a fitting swan song after all the innovative work carried out on the project since 1983,” said UK Nuclear and Nuclear Networks Minister Andrew Bowie.
“We are closer than ever to fusion energy thanks to Oxfordshire’s international team of scientists and engineers.”
JET’s new energy record was set using 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 water and make about 600 cups of tea.
It also surpasses its own previous record of 59 megajoules set more than two years ago.
If it operated continuously at 69 megajoules, it could power approximately 12,000 homes continuously.
JET was built as a research facility to demonstrate the promising potential of nuclear fusion to produce energy.
But it could be an ancestor of nuclear fusion power plants around the world that supply 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 diverting the use of fossil fuels such as coal and gas.
If nuclear fusion experiments can be harnessed on a much larger scale, reactors hotter than anything else in the solar system will provide unlimited clean energy. Tokamak Energy is a private 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 59 megajoules of thermal energy from fusion over a five-second period.
Pictured is an artist’s impression of the JET facility at the Culham Center for Fusion Energy, Oxfordshire.
“JET has operated as close to power station conditions as possible with current installations,” said Sir Ian Chapman, chief executive of the UK Atomic Energy Authority.
‘His legacy will be present in all the engines of the future.
“It plays a fundamental role in bringing us closer to a safe and sustainable future.”
Like other fusion reactors, the JET is a tokamak, a type of structure that uses powerful magnetic fields to confine donut-shaped “plasma.”
The hydrogen gas inside the container is heated to become plasma, a soup of positively charged particles (ions) and negatively charged particles (electrons).
In the tokamak, plasma is trapped and pressurized by magnetic fields until the energized plasma particles begin to collide.
As the particles fuse to form helium, they release enormous amounts of energy, mimicking the process that occurs naturally at the center of stars.
With a torus about six meters (20 feet) in diameter, JET is not the largest nuclear fusion reactor in the world.
The Japanese reactor, called JT-60SA and recently turned on in Naka, north of Tokyo, is a six-story tall machine measuring 50 feet high and 44 feet wide.
Fusion power works by colliding heavy hydrogen atoms to form helium, releasing large amounts of energy in the process, as occurs naturally in the centers of stars.
Built and operated jointly by Europe and Japan, the JT-60SA will be the world’s largest fusion reactor until the completion of ITER in France.
Other smaller reactors are being built and tested, including ST40 in Oxfordshire, which is more squished and compact compared to other doughnut-shaped reactors.
Fusion differs from fission (a technique currently used in nuclear power plants) because the former fuses two atomic nuclei instead of dividing one (fission).
Unlike fission, fusion carries no risk of catastrophic nuclear accidents – such as the one that occurred in Fukushima, Japan, in 2011 – and produces much less radioactive waste than current power plants, its proponents say.