Recent conflicts have focused attention on the need for secure and affordable electricity supply, while the increased extreme weather events associated with the climate change phenomenon requires low carbon generation. The 1990s saw a significant number of renewable technologies come forward to stake a claim in the energy market. As with all new markets some technologies did not make it past the design phase while others failed in the development phase. Thirty years later we can see that wind and solar energy have been hugely successful having emerged from the pack, and their deployment has gone beyond what was envisaged in those early years. The sector benefited hugely from the fact that many countries recognised the importance of renewables going forward and were involved in the development of the sector, with China prominent in the large-scale manufacture of both wind turbines and solar photovoltaic cells.
The small modular rector (SMR) sector in the 2020s is not unlike that of the renewables in 1990s insofar as there are many technology designs being explored, some of which are now being actively developed. There are micro reactors (<50 MW electric, MWe), standard reactors (50-300 MWe) and upper‑range SMRs (300-470 MWe). It is envisaged that there will be multiple reactors on a site, the number dependent on the needs of local industry and communities, and beyond that to support the national electricity supply industry.
Many countries have SMR programmes, for example, the USA, UK, Russia and China are major developers, Canada are early deployers and Lithuania and UAE are emerging deployment markets. There are a reported 7 SMRs either operating or in construction and more are in the development phase.
A key question is under what conditions might this fledgling market grow, and what might success for this sector look like over the next few decades. The basic drivers for this technology are growing electricity demand and security of supply, and to a lesser extent its low carbon attributes; key enablers are technology proof of concept and a well-formed policy and regulation framework. projects:t will need to encourage investment in the form of capital grants or generous subsidies, at least for the early projects; a shift by the World Bank and regional development banks to fund nuclear will also help and encourage other investors once they have confidence in the technology. Societal acceptance, particularly in local communities where such projects will be deployed, is also vital, as it has always been in nuclear projects. A convergence of these elements provides an environment for SMRs to be deployed in increasing numbers.
A common evolution of technology markets is in the form of an s-curve which begins with an initial period of experimentation, low adoption and slow improvement followed by a growth period with rapid improvement, scaling, and strong adoption of the winning technologies; the evolution enters a plateau brought about by slowing improvement, saturation in some markets, and certain limits are reached. Such a curve is evident for the mainstream civil nuclear programmes in the period 1955 to 2025 and it is possible then to adopt a similar s-curve to explore the likely future market for SMRs.
Using a starting point of 7 SMRs that are operating or under construction and applying the s-curve for the mainstream industry results in a sector with about 480 reactors operating worldwide in 2050. If the average SMR is 250 MW, then the equivalent total world capacity is about 120 GW; going a step further, if the load factor is 95% then the annual production of the global SMR fleet will be over 1000 TWh in 2050.
There is a second, more ambitious scenario possible in which a more pronounced s-curve is followed, brought about by fast maturing SMR technologies, easier and efficient deployment of multiple reactors on each site, and wider applications such as servicing the needs of date centres. In this scenario, about 820 reactors are operating worldwide in 2050. Again, if the average size of SMR reactor is 250 MW, then the worldwide capacity is about 200 GW delivering a production of 1700 TWh in 2050. By comparison, global wind and solar electricity generation reached a combined total of over 4,600 TWh in 2024, with solar generation reaching over 2,100 TWh and wind generating about 2,500 TWh.
This global fleet of reactors will likely be deployed in countries that already have the experience of using nuclear in their electricity generation mix, at least in the early decades: USA, China, Russia, Canada, UK, Japan, South Korea, India, France, and Germany; certain Middle East countries have also shown a strong interest in deploying this technology, to provide electricity for their domestic, business and industrial needs. SMRs, by virtue of their scale and utility, are more likely than the traditional nuclear plants to enter new markets.
The SMR sector, then, is set to grow significantly over the next few decades, and the market will offer many opportunities for investment and employment. For this to occur, Government, working with the nuclear and wider industries involved, must ensure that similar safeguards will be in place for the SMR sector as that for the mainstream industry, including a strong regulator. It is incumbent on the global nuclear community and its institutions to continue to offer support and guidance to countries new to the nuclear sector.
My book, Who Needs Nuclear Power, provides a holistic view of the current and potential role of civil nuclear power, including SMRs, in the world’s energy mix.
Published in April 2026.