Mike Middleton shares his thoughts on new nuclear in the UK's future energy system

13th October 2015

Most scenarios for the UK’s future energy system now include nuclear energy as playing a part in the overall mix. But, how big a role is there for new nuclear within a low carbon energy system and is there the potential for smaller modular reactors (SMRs) as well as the more familiar larger ones?

ETI’s modelling work to define a UK low carbon energy system transition to 2050 features new nuclear as a prominent component alongside bioenergy, conventional power stations fitted with carbon capture and storage (CCS), a more efficient use of heat and offshore renewables.

Following on from this work we have published “The role for nuclear within a low carbon energy system,” a new report which includes analysis from recent ETI projects on how large and small modular reactor nuclear technologies can contribute to decarbonising the UK energy system.

The report summarises the insights from our projects on Power Plant Siting, delivered by Atkins, and System Requirements For Alternative Nuclear Technologies delivered by Mott MacDonald together with our own in-house energy system modelling and analysis which incorporates the learning from both projects.

This has created a new understanding of the potentially different but complementary contributions from large baseload reactors and SMRs in providing baseload electricity production and flexible combined heat and power generation.

We believe that large reactors are best suited for baseload electricity production and our analysis indicates an upper capacity limit in England and Wales of around 35 GWe by 2050, but the actual deployment level will be influenced by a number of factors and could be lower.

In addition to these, SMRs could fulfil an additional role by delivering combined heat and power which in itself has an important role in the decarbonisation of energy use in buildings.

Due to their smaller size and easier siting SMRs offer more flexibility and could deliver low carbon heat into cities via hot water pipelines up to 30km in length. This flexibility opens up new potential sites.

If you add the potential of SMRs into the equation the total nuclear contribution in the 2050 energy mix could be around 50 GWe.

But, and it is a big but, future nuclear technologies will only be deployed if there is a market need and these technologies provide the most cost effective solution.

And, a decision is required now whether to begin 10 years of enabling activities leading to a final investment decision for a first commercially operated UK small modular reactor if they are to be operational by the 2030s at the earliest

There will of course be other obstacles to overcome so a strategic approach to reactor siting together with public consultation will be important in determining the extent of the deployment of both large nuclear and small modular reactors.

The next 10 years will be critical in developing the deployment-readiness of key technology options for the UK’s low carbon transition to 2050.

New large scale reactor designs are already being deployed outside the UK and are suitable for deployment in the UK. Regarding SMRs, there is still much uncertainty about the costs and  schedules for potential deployment in the UK, but action needs to be taken now if the option to deploy SMRs as part of the low carbon energy system transition is not to be closed off.

However, if proper planning and preparation starts now and continues over the next 10 years new nuclear plants can form a major part of an affordable low carbon transition, with both large nuclear and small modular reactors potentially playing a role.