Why Britain could soon be building mini nuclear reactors

Industry touts 'Small Modular Reactors' as a solution to our energy needs - and the Government may invest £2bn in the idea

The idea of cheap, emission-free energy from a fleet of British-designed and built mini nuclear reactors that are cheaper and faster to build than their conventional counterparts is something of a no-brainer for the Government.

When these so-called “Small Modular Reactors” (SMRs) come with prospect of creating a huge new industry with strong export potential, it’s no wonder ministers are considering injecting up to £2bn of taxpayer money to get the concept off the ground.

A consortium including Rolls-Royce, Atkins, Laing O’Rourke and the National Nuclear Laboratory are pushing the development of SMRs.

They hope that by 2050 more than a dozen of the reactors, which each take up less space than two football pitches, will be operating in the UK. Each will pumping out 440 megawatts  - about a seventh of the amount set to be produced by Hinkley Point, which has seen costs spiral to £22.5bn.

Using experience gained from building nuclear submarine power plants, Rolls and its fellow consortium members hope to industrialise production of the mini reactors, which can be put on trucks and bolted together on site. This would speed up production and reduce the cost, they say.

It seems a simple idea, but with one obvious question: if SMRs are so good why hasn’t it been done before?

“It’s a relatively new idea because there wasn’t the need for them before,” says Tom Greatrex, chief executive of the Nuclear Industry Association.

He says SMRs appeared as a serious concept about a decade ago as green concerns gained importance. They are easier to switch on and off than traditional plants, meaning they can match demand faster.

This is becoming necessary as polluting coal and gas plants that previously performed that duty are phased out and power supply needs to be matched with variable supply from renewables such as wind and solar.

“SMRs can create a clean, reliable backbone to the national grid when the wind doesn’t blow and the sun doesn’t shine,” says Tom Samson, boss of the UKSMR consortium.

The consortium is not the only game in town. US-based NuScale is also looking at SMRs, touting a 60 megawatt basic design that can be joined together to create a plant producing 720 megawatts.

Greatrex adds that both groups have designs that are the “closest to being deliverable” - but warns it's wrong to expect the UK to abandon traditional nuclear power plants just yet.

“You need both, they are complementary,” he says. “The attraction of SMRs is economies of volume: having lots of them which are cheaper to build - and that’s why ‘modular’ is key - but they don’t each generate so much. For traditional, big plants the attraction is economies of scale: they are expensive to build as it’s done on site, but they produce more at a lower price once up and running.”

The spiralling costs of Hinkley and problems with the huge initial investment needed that have seen Toshiba and Hitachi pull out of plans to build traditional nuclear plants in Wales and Cumbria will also no doubt be an influence on government thinking as it weighs up pumping in state funds.

Rolls-Royce has experience building nuclear power plants for Royal Navy submarines

And it is cost, along with the intense regulation around atomic energy, that is holding back SMRs.

UKSMR’s Samson thinks it will take a decade to get the first mini reactor operating, and puts the price tag at “£2bn-plus”. However, this depends on government support to drive through regulation and a commitment that another five SMRs will be ordered, which will each cost £1.8bn. That takes the bill to £10bn-plus - assuming no problems crop up. 

“This is not a new type of fuel or reactor, this is based on existing technology and there are no insurmountable challenges,” Samson adds. “But we need a commitment to a new fleet of SMRs so we can get the supply chain involved.”

In a way, mini reactors face the same capital intensity hurdle that traditional nuclear power plants do.

Greatex agrees: “Almost all the cost is in the construction for a normal plant and it is relatively cheap afterwards. SMRs need government to backing to kick off - you wouldn’t build a factory to build just one car. But once it’s proven and costs go down you can see private financing coming in.”  

Just as with traditional plants that need the state to effectively underwrite them to get private industry involved, SMRs need a similar guarantee for business to go ahead and spend billions on a technology that is as yet unproven.

Both UKSMR and NuScale also highlight the red tape around developing new nuclear technology as part of the reason mini reactors are not already powering our homes.

“Getting a first of a kind nuclear technology designed and approved is an incredibly time-consuming and costly business,” says Diane Hughes of NuScale. “Just the schedule for the regulatory review process alone is several years.”

Should ministers take the plunge and commit public money, SMRs are unlikely to be springing up at the bottom of your garden - though their size means they could, in theory.

“There’s a huge opportunity in old nuclear, coal and gas power plant sites which are being decommissioned,” says Samson. “We’re not planning to put them at the end of your street.”