Expert Q&A: small modular reactors

Experts from Rolls-Royce, Atkins and the Nuclear Industry Association comment on the potential of small, modular nuclear reactors

Small Modular Reactors (SMRs) have the potential not only to play a key role in the UK’s Net Zero ambitions, but also to become a new export sector and assist countries around the world transition to low-carbon energy. The Engineer caught up with some key figures from the UKSMR consortium and the nuclear industry to find out more.

small modular reactors
Rolls-Royce's small modular reactor design. Image Rolls-Royce Plc

Meet the experts

Matthew Blake: Chief Engineer – Small Modular Reactors, Rolls-Royce Plc

Tom Greatrex: Chief Executive, Nuclear Industry Association

Peter Sell: Chief Design Engineer  - UKSMR, Atkins

How important is new nuclear for the UK’s net zero goals and how do you see SMRs fitting into the overall picture?

Peter Sell: New nuclear power is vital in the development of infrastructure for meeting the UK and global Net Zero commitments. It needs to be part of a mix of solutions, including renewable sources, to meet our Net Zero requirements. New nuclear has several components which can be part of the solution, including large nuclear (e.g. Hinkley Point C and Sizewell C) and Small Modular Reactors (e.g. UK SMR).  Both large nuclear power plants and SMRs are included in the recent government announcements and are part of the Net Zero solution.  They can also be part of diverse energy solutions such as hydrogen generation, e-fuels and district heating systems.

SMRs provide an opportunity to utilise modern methods of construction, develop on more compact sites, with repeatable schedule and cost confidence, to deliver zero carbon reliable electricity generation to meet the net zero commitments. This needs industry and government working together to deliver these innovations and in the UK we have started that journey with the UKSMR.  The criticality of delivering new nuclear as one of the solutions to net zero is becoming more stark everyday given the recent IPCC report.

Tom Greatrex: Put simply, the UK needs new nuclear to hit net zero. Nuclear is the only proven source of firm, low-carbon power we have in the UK. Over its lifetime, nuclear has saved a staggering 2.3 billion tonnes of emissions, more than any other source. But we need much more of it to meet increasing power demand, and SMRs will have a critical part to play. One UK SMR will be able to power a city the size of Leeds, power over 60,000 electric cars in this country, and sustain critical jobs and capabilities across a strong UK supply chain. That’s not all, they could also be used to produce hydrogen and synthetic fuel to help decarbonise other sectors like industry and heating.

Matthew Blake: Nuclear power is a fundamental component to the UK and the global achievement of Net Zero. That is why SMRs are such a prominent constituent of the government’s ‘Ten Point Plan for a Green Industrial Revolution’. Governments and industrial companies need reliable, affordable low carbon power sources to achieve their Net Zero targets. Nuclear is acknowledged as a ready-now low carbon technology but to-date has only been affordable by the governments of a few major world economies. Rolls-Royce SMR’s ambition is to disrupt that paradigm and offer a low-cost, deliverable, global and scalable and investable solution, that can be rolled out around the world.


What are the key technical challenges for SMRs, both in the reactor technology itself and the manufacturing process?

TG: This is a first of a kind reactor, so naturally there are challenges. Firstly, there is a need to go through the UK’s generic design assessment (GDA), then there’s the site approval process, and the engineering and supply chain challenges. There is also global competition with new designs in development over the world. The UK, though, is in a great position to meet these challenges, with a world-class skills base and a second to none track record of developing new and existing technologies.

MB: Rolls-Royce SMR is a radically different approach to delivering new nuclear power. By taking advantage of factory-built modularisation techniques that drastically reduce the amount of on-site construction, we can deliver a low-cost nuclear solution that is competitive with renewable alternatives. At the heart of the Rolls-Royce SMR business lies the innovative repackaging of reliable and proven technology, allowing off-site modular construction using standard components and advanced manufacturing techniques. We are bringing established approaches to delivering nuclear in a new way.

small modular reactors
Image Rolls-Royce Plc

PS: There are many technical challenges of developing a nuclear power plant, but for SMRs the ability to design and deploy them fast enough to support our net zero commitments is key. On the technical front, the technology challenge benefits from being readily deployable and well understood with supply chains in place or available to support design development and delivery through construction to operation. A key benefit of SMRs is the modular element and the focus on developing the technical solutions to deliver a modular solution in construction and assembly is vital.  This early thinking that has been exemplified in the UKSMR project will yield benefits throughout the delivery of the design, manufacture and assembly of the UKSMR and it is a strategy with will deliver confidence in repeatability.

How important is it to get public buy-in for the project, particularly from people who will be living in the vicinity of SMR sites?

MB: Communities located in the vicinity of the nuclear industry are often its most supportive advocates. We do not take this support for granted and have developed an approach to site delivery that minimises disruption through modularisation and site construction in a factory setting.

Most of the existing UK nuclear fleet will be offline by March 2024, and all but one plant by 2030 – that is a significant shortfall in stable, low carbon electricity and we see a tremendous opportunity for SMRs to fill a significant proportion of that gap.

TG: UK SMRs can be deployed at any nuclear licensed site, in communities where there is already an understanding of the economic and environmental benefits of nuclear. Activities are underway to explore other possible sites too. Public buy-in, though, is essential at every step of the process. Work has already started on public engagement to further understand public insights and expectations around the potential future siting of SMRs.

PS: Public buy-in for nuclear power both globally and locally is important. Overall, as the impact of climate change is further understood, people are more supportive and positive towards nuclear power. In the UK we have a great pedigree of nuclear power and the communities around the existing fleet are generally very supportive of new nuclear given their positive impact on their communities.

SMRs will be more compact and easier to build than the previous generation of power plants reducing their construction impact, however still providing long term opportunities for people and communities.

There will be robust regulation associated with the planning and environmental aspects as well as the Generic Design Assessment of SMR plants in the UK. This will provide opportunities for people to be involved in the development of plants in their local vicinity.

Much has been made of the potential export market for SMRs. Where are other countries on the technology and where do you see as potential overseas markets for UK SMRs?

MB: We see a huge opportunity to support decarbonisation efforts in a range of countries. We have signed Memorandums of Understanding with Estonia, Turkey and the Czech Republic and see huge opportunities to develop in a range of markets that could create a £250 billion export market for Rolls-Royce SMRs.

small modular reactors
Image Rolls-Royce Plc

As well as the electricity provision, we see a huge opportunity to utilise Rolls-Royce SMRs for the Net-Zero manufacture of green hydrogen and synthetic fuels, for which international demand will only continue to grow.

TG: Global interest in SMRs has been building with some momentum in the last few years as countries aim to meet ambitious climate targets and cut emissions. The US and Canada have shown particular interest with both countries developing their own SMR technologies and designs. UK SMRs will be able to tap into these developing global markets, with the potential of being worth billions of pounds as countries wean themselves off coal, gas and oil. UK SMRs are also highly scalable -  parts can be exported anywhere where there is a market. The sky really is the limit.