SMRs – a plausible reality for the UK

Small modular nuclear reactors, or SMRs, are a hot topic at present. Advanced SMRs are currently being built in Russia, China and Argentina, and more than 45 SMR designs are at various stages of development.

At the Spending Review and Autumn Statement 2015, the UK Government announced it would invest £250m ($311m) in nuclear research and development over five years; this includes a competition to identify the best value SMR design for the UK.

SMRs: What and why?

The International Atomic Energy Agency (IAEA) definition of a small modular reactor (SMR) is an advanced reactor that produces electric power up to 300MWe and is designed to be built in factories and transported to site, unlike current nuclear power plants which are assembled and constructed on site. To put the generating capacity of SMRs into perspective, the two European Pressurised Reactors planned for Hinkley point C will each have a capacity of 1600MWe.

Most nuclear plants are used for the generation of electricity alone, however generated heat can be used in applications such as desalination, process heat or district heating. Some nuclear plants utilise this heat energy through cogeneration, also known as Combined Heat and Power (CHP). This increases the efficiency of the plant.

A benefit of SMRs over large reactors is that they are less limited by location; they can be sited close to large population centres, they have lower requirements for cooling water and they are ideal for remote areas with less developed infrastructure. Large nuclear plants are often required to be located at a distance from major population centres to simplify emergency planning/reduce accident consequences to the public.

A good example of a SMR that fulfils many of the advantageous applications SMRs have over large plants is the KLT-40S SMR, currently under construction in Russia. The barge-mounted reactor is to be used for the cogeneration of process heat and electricity for remote population centres. It can be moored up in any coastal region, negating the required infrastructure for land based nuclear plants such as transmission lines and transport links.

SMRs in general are of simpler design than large reactors due to their larger surface area to volume ratio. This allows for some of the engineering required for safety in large reactors to be removed from their design. Most SMRs will have a high level of passive or inherent safety within their design meaning that in the event of a malfunction, safety will depend on measures that require no action by a safety system or an operator to achieve and maintain a safe state. Passive features include engineered solutions, such as pressure release valves, whereas fully passive and inherent features rely on physical phenomena such as convection, gravity or resistance to high temperatures.

UK interest in SMRs

The UK Government first expressed an interest in SMRs when it published The Nuclear Industrial Strategy in 2013. In 2014 a feasibility study was commissioned by the UK Government to assess the technical, economic and commercial case for the deployment of SMRs in the UK. The study was led by the National Nuclear Laboratory (NNL) in collaboration with a consortium of companies and was published later that year. The study found that SMRs offered the possibility for the UK to engage in collaborations with SMR vendors and UK industry and they were potentially deployable within a 10-year timeframe. The study predicts a UK SMR market of around 7GWe and a potential global SMR market of 65– 85GWe by 2035. This is valued at £250–450 billion. These figures represent the potential markets for the application of electricity generation only; applications outlined above were not considered in the feasibility study.

Following the feasibility study, the UK Government “announced that DECC [which later merged into the Department for Business, Energy and Industrial Strategy (BEIS)] will invest £250m in an ambitious nuclear research and development programme, enabling the UK to be a global leader in innovative nuclear technologies. This includes a competition to identify the best value SMR design for the UK”.

Phase One of the Small Reactors Competition was launched in March 2016 with the objective to gauge market interest among technology developers, utilities, potential investors and funders in developing, commercialising and financing SMRs in the UK”.

In parallel with Phase One, an SMR Roadmap is to be developed. The SMR Roadmap “will summarise the evidence
so far, set out the policy framework and assess the potential, for one or more possible pathways for SMRs to help the UK achieve its energy objectives, while delivering economic benefits”. An allocation of at least £30 million was made within the 2016 Budget for an SMR-enabling advanced manufacturing R&D programme to develop nuclear skills capacity.

There are 33 participants in the Small Reactors Competition. SMR developers who have publically expressed interest in UK development and have released information about their proposals include; Rolls Royce, Westinghouse, Nuscale Power, Urenco, China National Nuclear Corporation, Generation mPower, Moltex Energy and GF Nuclear.

What happens next?

The UK government have identified the potential advantages to investing in the development of SMRs within the UK and are currently assessing their options. Interest from SMR developers and industry is high, however, it must be established that SMRs make a viable contribution to the UK’s energy mix and provide wider economic benefits such as high-value sustainable jobs and export opportunities for UK suppliers before the government commit to a sustained support programme, such a programme could see the first UK SMR deployed within 10-15 years.

The results from Phase One of the Small Reactors Competition and the SMR Roadmap are anticipated sometime in 2017. The winning design is expected to begin the UK’s generic design approval process.  

Author notes: Dr. Lisa Wearing is Nuclear Safety Engineer, Pöyry Energy Ltd.