How nuclear fusion could become a reality in Scotland – Professor Declan Diver

It seems like the topic of energy is in the headlines a lot these days. Skyrocketing power bills, the urgent need to decarbonise our national grid to combat climate change, and the challenges to energy security caused by the war in Ukraine are rarely far from the front pages.

Nuclear fusion power plants would recreate processes that happen within the Sun to create electricity, without the risk of a Fukushima-style disaster (Picture: Nasa via Getty Images)

Amid those stories, you might also have seen increasingly regular stories about encouraging developments in a new type of power generation, with remarkable potential for achieving net-zero goals – fusion power.

There are dozens of companies around the world working to establish fusion power generation as a commercial technology. They have the financial backing of billionaires like Bill Gates and Jeff Bezos as well as corporations like Google and Chevron.

Meanwhile, key advances in fusion research are occurring with increasing frequency. In February, the Jet laboratory in Oxford sustained a record-breaking test run of power generated by fusion. There will undoubtedly be more to come, and they will come soon.

The UK Government has committed to doing its part to develop fusion power with an ambitious project: the Spherical Tokamak for Energy Production (Step), a prototype fusion power plant which will be live by 2040. It will form the template for commercial fusion power plants around the world.

But what is fusion, and how does it work? Fundamentally, it is the process that powers the sun and every other star in the universe.

Deep in the heart of stars, in conditions of almost unimaginable heat and pressure, hydrogen atoms are crushed together until they fuse to form helium, releasing a vast amount of energy in the process.

Fusion power reproduces a tiny fraction of that awesome process on Earth in a doughnut-shaped reactor called a tokamak.

In a tokamak, deuterium and tritium, isotopes of hydrogen, are confined by powerful magnetic fields and forced together to produce helium and energetic neutrons. The energy released by this zero-carbon process will be captured and harnessed for electricity production, helping to reduce our reliance on fossil fuels.

It differs from nuclear fission, the process which occurs in conventional nuclear power plants, in a number of key respects.

Firstly, since fusion power requires the unique conditions of a tokamak to occur at all, it cannot cause the kind of runaway meltdown reactions seen in places like Chernobyl and Fukushima. When power to fusion reactors is cut, the reactions stop instantly.

Secondly, they create very different by-products. Fission reactors produce solid radioactive waste which can take thousands of years to decay to marginal safety. The tritium used as fuel in fusion reactors, on the other hand, has a half-life of just 12 years, and the only by-product of the process is helium, a harmless inert gas.

The difference in the scale of any potential hazard is part of the reason why the UK Government announced in June that future fusion facilities will be regulated differently from fission plants, which are overseen by the Office for Nuclear Regulation.

Fusion power plants will be overseen by the Environment Agency and Health & Safety Executive, putting them on the same footing as any other industrial infrastructure project.

Why might we want to invest in fusion power, though, when renewables like wind, solar and wave power are mature technologies which are becoming ever-cheaper to build, run and maintain?

One answer is that some renewables, like wind and solar, are still dependent on environmental conditions. It makes sense to consider alternative sources of power to supplement their contributions to the national grid on days where the wind is weak or the sun is behind the clouds. Fusion could be a valuable part of a fleet of low-carbon power generation options, ensuring energy security and independence as we achieve net-zero.

Another advantage of fusion power stations is that they could also help drive other industries towards net-zero. Step will operate at around 700 degrees Celsius, and excess heat could be siphoned off to contribute to a local district heating project, or used in the production of cement or glass – both of which are currently carbon-intensive processes.

I’m a plasma physicist at the University of Glasgow. I’m also the convenor of the Fusion Forward (Ardeer) consortium, along with colleagues from North Ayrshire Council and NPL Group. Last year, we put together a bid to bring Step to Ardeer, on the North Ayrshire coast.

That bid is now one of five in the final stages of consideration by the UK Government, with a decision expected later in the year.

It’s the only Scottish bid still in contention, and it has the potential to revolutionise the country’s economy, with an expected total investment of £20 billion.

There will be around 3,500 skilled jobs while the plant is under construction and, once operational, work for up to 1,000 engineers, technicians and support staff.

And it will bring much more than that, with its need for advanced welding, materials science, diagnostics, gas-handling systems, robotics, artificial intelligence, magnetics and more. We expect established companies and new start-ups will be drawn to the area to help meet those needs, and exploit new industrial innovation.

Advanced science brings with it fresh education, training, skills and opportunities to build a local workforce in the west of Scotland. Colleges and universities across the area have agreed to work together to create and deliver new courses designed to meet Step’s education and training needs, from apprenticeships to PhDs.

Those energy-focused headlines are unlikely to be going away any time soon. But I hope that in the coming months we’ll also be celebrating the news that Step will be based at Ardeer, and bringing with it one of the answers to our net-zero future.

Declan Diver is professor of plasma physics at the University of Glasgow and the convenor of the Fusion Forward (Ardeer) consortium