World Nuclear Association has called on policymakers to accelerate the development and commercialisation of small modular reactors (SMRs) as well as fast-tracking the deployment of large-scale reactors in a policy paper released today. The message is clear that to limit global warming to below 1.5 degrees Celsius, global carbon emissions must decrease rapidly, the Association says in The need for large and small nuclear, today and tomorrow. A global effort towards establishing a sustainable energy system - with the electricity sector at the heart of it - is under way, and the need for clean, abundant and affordable electricity is widely recognised, it says.

Large nuclear reactors are the only proven low-carbon technology that can be deployed at the scale and with the timings needed to meet the goals of the Paris Agreement, but the role of SMRs in decarbonisation is expected to grow rapidly in the 2030s and 2040s, it says.

The Association makes five recommendations to policymakers:

to consider the role of all nuclear technologies - both large-scale and SMRs - in long-term and sustainable energy strategies;

to actively explore the use of nuclear technologies in applications such as industrial heat and the production of green hydrogen;

to fast-track the deployment of large-scale reactors to meet demands for clean and reliable energy and fulfil climate change commitments;

to accelerate the development and commercialisation of SMRs, including taking steps to address regulatory challenges and promote international harmonisation; and

to work closely with multilateral banks to find ways to match growing electricity needs in developing countries with nuclear, rather than fossil fuel, solutions

The use of nuclear energy provides an "affordable fast-track to a high-powered and clean energy system", it notes. There is an "urgent, and immediate" demand for clean energy in developing countries, where IPCC scenarios suggest electricity demand is set to double over the next 20 years, it says.

"It is crucial that access to the most efficient and low-carbon solutions - both in terms of technology and financing - is provided to enable sustainable growth," the paper says. Also, as of 2019, some 940 million people - primarily in Sub-Sharan Africa and South Asia - had no access to electricity. "By investing into large and small nuclear reactors, we can bring the modern world to the hundreds of millions who currently live without electricity," the paper says.

The large nuclear reactors currently operating around the world provide secure and stable electricity for their national grids. Large nuclear will remain the backbone of many clean energy systems and there are "shovel-ready" nuclear projects around the world: an additional 14 GWe of nuclear energy could be in operation by 2035 "should the decision be taken now", the Association notes. However, there are also considerable future opportunities for SMRs to complement them by opening new markets and applications for nuclear energy, it says.

SMRs are reactors of less than 300 MWe capacity, either of conventional light-water design or advanced (so- called Generation IV) concepts, which might be built as modules in a larger plant, or built separately. They may be better suited to the generation of industrial and residential heat - broadening the use of nuclear in applications including desalination and hydrogen production, the Association said.

In addition, SMRs are well-suited to remote or small grids where deployment of large reactors would not be practical: "The use of both large reactors and SMRs can help meet the needs of a wide range of sectors, broadening energy decarbonisation efforts beyond the electricity sector."

The knowledge, supply chain and experience from large reactors is crucial for the successful deployment of SMRs, but significant development and investment will be required to bring them to the market as commercial products, the paper says.

There is already global experience in operating small-scale nuclear reactors - as well as the reactors that power icebreakers and aircraft carriers - and designs for commercial SMRs are at advanced development stages.

Several developers expect the first SMRs to begin commercial operation in 2028-2030. "Once demonstration reactors have been completed and a fleet of SMRs deployed, there is going to be a good return of experience and cost reduction, further strengthening the commercial viability for specific designs," it says.