By Darren Gunning, Cavendish Nuclear Clean Energy Programme Manager
As nations work to meet ambitious net zero targets while maintaining secure and affordable energy supplies, a new generation of nuclear technologies is gaining momentum. Small Modular Reactors (SMRs) and Advanced Modular Reactors (AMRs) are increasingly recognised as vital tools in the transition to a low-carbon future, offering the potential to deliver reliable energy, strengthen energy security and support industrial decarbonisation.
Unlike traditional large-scale nuclear power stations, SMRs and AMRs are designed using modular construction techniques. Components are manufactured in factory-controlled environments before being assembled on site, creating a more efficient, repeatable and predictable delivery model. This approach can improve quality, reduce construction timelines and lower project risk, helping accelerate deployment.
While the two technologies are often discussed together, there are important differences. SMRs are generally based on proven Generation III reactor designs and are primarily focused on providing dependable, low-carbon electricity. AMRs, by contrast, represent the next evolution of nuclear technology. Built around advanced Generation IV concepts, they offer enhanced capabilities, including the ability to produce high-temperature heat for industrial applications.
This distinction is important because many of the sectors most difficult to decarbonise require far more than electricity alone. Industries such as chemicals, steel manufacturing and hydrogen production need large quantities of heat. AMRs have the potential to provide a low-carbon alternative to fossil fuels, helping industries reduce emissions while maintaining productivity.
Safety remains at the heart of both technologies. SMRs build on decades of operational nuclear experience, while AMRs introduce innovative passive safety features. These systems are designed to safely shut down and manage heat without requiring active intervention or external power sources. The result is a new generation of reactors that combines proven nuclear principles with advanced engineering solutions.
The environmental case for deployment is equally compelling. As renewable energy sources such as wind and solar continue to expand, there remains a need for reliable, low-carbon generation that can operate regardless of weather conditions. SMRs and AMRs can provide that stability, supporting the wider energy system while helping reduce dependence on carbon-intensive fuels. Their smaller footprint and modular design also offer greater flexibility in where and how they can be deployed.
In the UK, momentum is building. Programmes supported by Great British Energy – Nuclear and the Advanced Nuclear Framework are helping move technologies from development towards deployment. Projects involving Rolls-Royce SMR, X-energy and other advanced reactor developers are laying the foundations for a new era of nuclear delivery, while strengthening domestic supply chains and creating high-value jobs.
The opportunity extends well beyond the UK’s borders. Internationally, SMRs and AMRs offer a scalable solution for countries seeking secure, reliable and low-carbon energy. Their modular nature allows deployment in locations where traditional nuclear power stations may not be practical, opening new opportunities for economic development and energy independence.
Future applications could be transformative. Beyond supplying electricity to the grid, SMRs and AMRs could power remote communities, industrial facilities, offshore operations and critical national infrastructure. There is also growing interest in their potential use in maritime and defence sectors, where resilient, deployable energy sources could provide significant operational advantages.
Challenges remain, including regulatory approvals, supply chain development, workforce capacity and commercial financing. However, as technologies mature and deployment gathers pace, these barriers are increasingly being addressed through collaboration between government, regulators and industry.
SMRs and AMRs are no longer technologies of the distant future. They represent practical solutions capable of supporting net zero ambitions, enhancing energy resilience and driving sustainable economic growth. For the UK, they offer a unique opportunity to combine world-class nuclear expertise with advanced manufacturing capability to help shape the future of clean energy, both at home and internationally.