Oxfordshire nuclear fusion reactor celebrates 40 years of pioneering scientific discoveries

  • ITV Meridian's Ciaran Fitzpatrick is granted rare access behind the scenes of Culham's nuclear fusion reactor

A "world-leading" nuclear fusion reactor is celebrating 40 years of operation as ITV News Meridian takes a look around the facility.

At Culham research facility visitors are immediately struck by the sheer scale of its importance.

The nuclear fusion machine is incredibly large, several flights of stairs are needed to reach the top and it towers above one of the largest buildings I've ever been to.

Scientists hope nuclear fusion, a process that powers the sun, could be our main source of energy within the next half century.

This reactor in Oxfordshire has been at the forefront of groundbreaking - and record-breaking experiments - to find cleaner ways of powering our planet.

Born out of the oil crisis in the 1970s and the need for western governments to move away from fossil fuels, the research facility into nuclear fusion began in earnest in 1984.

And ever since, it's been record after record being broken. World first and groundbreaking vital science tucked away in the Oxfordshire countryside.

Scientists hope nuclear fusion, a process that powers the sun, could be our main source of energy within the next half century. Credit: ITV News Meridian

A recent record broken by the team at JET (Joint European Torus) facility, comes at a time of change.

This is because after more than 40 years, the decades' long work of some of the best scientists in the world, is coming to an end.

Researchers generated 69 megajoules of energy over five seconds from a mere 0.2 milligrams of fuel in the final fusion experiment in December 2023.

The burst of energy, equivalent to 16.5kg of TNT, was described as a “fitting swansong” for the project, which has pioneered technology for future commercial fusion reactors since it began operating in 1983.

It beat the previous record of 59 megajoules of heat, set by the same facility in 2022.

What is nuclear fusion?

  • Nuclear fusion is the process that powers the sun, where two atoms fuse together, liberating huge amounts of energy.

  • Fusion works by pressing hydrogen atoms into each other with such force they combine into helium, releasing enormous amounts of energy and heat.

  • The reaction happens when two light nuclei merge to form a single heavier nucleus. Because the total mass of that single nucleus is less than the mass of the two original nuclei, the leftover mass is energy that is released in the process.

  • In the case of the sun, its intense heat - millions of degrees Celsius - and the pressure exerted by its gravity allow atoms that would otherwise repel each other to fuse.

At a special event marking 40 years of pioneering research, the Nuclear Minister Andrew Bowie MP, said plans for the UK's first commercial facility in Nottinghamshire, would not be possible without all the work at Culham.

It is also about looking ahead "towards the commercialisation of fusion, and ultimately delivering power generated by fusion into British homes".

But decommissioning a nuclear fusion reactor is not a simple task and it has never been done in the world before.

The team at Culham - once again, at the forefront of learning about this technology for the rest of the world to use too - in their own reactors.

Taking apart the machine will "all be done with robots" said the CEO of UK Atomic Energy Authority professor Sir Jim Chapman.

"There's four tonnes of metal, all disassembled robotically and then we take apart the vessel itself," Chapman remarked.

They will also capture the fuel which is embedded in the metal and capture it back - to reuse it to not waste any vital energy.

I got a tour of their robotic lab, which showed several scientists working together with a person physically moving the robot inside the machine.

The painstaking process will take years in order to remove the inner parts.

A full decommission is a long way away, possibly in the next 15 years.

It is widely appreciated any future steps towards a full commercial reactor wouldn't have come anywhere near a possibility without the work in Culham.

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