Can small modular reactors fill upcoming gaps in energy supply?

Rich McEachran

How a small modular reactor (SMR) could look (Credit: Rolls-Royce)
How a small modular reactor (SMR) could look (Credit: Rolls-Royce)

For many of you, but especially those who grew up in the 1970s and 1980s, nuclear power is likely to remind you of cooling towers that loom large over the side of motorways.

Often reminiscent of Brutalist architecture, these concrete structures have often been criticised for their aesthetic.

While safety measures have come a long way since the days of Chernobyl, residents that live near to these eyesores have often been concerned for their health. Back in 2016 and 2017, Belgium reported micro-fractures in a couple of nuclear reactor facilities. Such was the concern that an incident might occur that the authorities in the Netherlands handed out iodine pills to those living near the border in case of radiation poisoning. 

Belgium plans to transition away from nuclear power and switch off its reactors by 2025, but to do so will require significant investment in either gas-fired power or renewables. The country has long had a reliance on nuclear power and surveys have shown that over the past few years more and more Belgians have been in favour of keeping plants in operation. A fear is that switching them off could result in power cuts.

Plugging the gaps

Belgium isn’t the only country in this precarious position. A host of other nations have ambitions to phase out nuclear power. 

Succeeding in achieving this goal will require innovation and investment in generating power from alternative and sustainable sources. Meeting demand won’t be easy, though, and there could end up being gaps in the energy supply. Could small nuclear reactors be deployed to fill these gaps?

The answer is yes, according to Rolls-Royce. The manufacturer has developed prototypes of small modular reactors (SMRs), which could be transported around the UK and deployed at locations where energy supply isn’t meeting demand. They could supplement energy generated by renewables – solar power and windfarms. 

The SMRs that Rolls-Royce has designed are 16m in height and just 4m in diameter. One SMR can be housed within a power station that’s a little bigger than five times the size of the Wembley pitch. Rolls-Royce has plans for 16 SMRs, so far, with the first to be up and running by the beginning of the next decade.

A report published last summer by the Nuclear Industry Association warned that the UK’s net-zero target would be at risk if it didn’t consider building smaller and advanced nuclear reactors. The UK has seven nuclear sites in operation, providing 20% of the country’s electricity, yet six of these will go offline by 2030, so there’s a clear need for innovation to prevent a nuclear-sized chasm from opening up in the energy network. 

Keeping down costs

Tom Samson is interim chief executive of the UK SMR Consortium, hired by Rolls-Royce in its push to deploy SMRs across the country. He said that all the components of an SMR could be made in a factory, before being joined together at a desired location. “This is going to reduce costs greatly and the time spent constructing on site,” said Samson. 

There are added benefits to taking this approach. One is that the latest technology can be used to ensure designs are as cutting edge as possible. Streamlined manufacturing and assembly can make nuclear power more affordable. 

Another benefit of speeding up the delivery is that supply chains are shortened – there’s less need for as many contractors as would be involved in a typical nuclear energy construction project. And, because of this, emissions are lower. 

All in all, this makes SMRs an attractive proposition, particularly to private investors. While the project has received £215m in funding from the government, Rolls-Royce recognises that private investment will also be key to scaling up the initiative. The technology could potentially be sold in overseas markets. 

As Samson explained: “Factory-built SMRs can be rolled off assembly lines cost-effectively to deliver energy to where it’s needed and meet the demand for flexible power generation.” 

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Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.


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