There is a recent interest in the small modular reactors (SMRs) that support a plant electricity generating capacity of up to 300 MWe. There are over 70 reactor designs at various stages of development. Because of their small size, they can be constructed in clusters at a power plant site; and because of their modular nature, they can be built in a factory environment that facilitates economy and quality.

They also reduce the demand for cooling, hence permitting plant operations at remote inland locations. Some of their adopted technologies enable reactor operations at temperatures above 800°C; this supports process heat and hydrogen production. Those SMRs constructed in succession to match a large nuclear power plant of the same generation capacity will have the advantage of shorter construction time per unit. This will lead to earlier electricity generation, hence earlier investment returns.

Proponents have suggested that the SMRs will be accepted for their merits and will open up a market furthering their competitiveness.

Although the SMRs (which have embraced the latest technologies) have certain technical merits over reactors currently in operations, their market growth will require the following: standardisation in design, modularisation in manufacture and construction, and experience learning over time. These support their competitiveness by the economy of volume in contrast to the economy of scale, which has supported today’s commercial reactors which typically have a capacity of 1000 MWe.

A new approach often faces a new set of challenges. Firstly, regulatory acceptance of novel reactor features is required. Secondly, new supply chains are needed for an innovative design to enable commercial competitiveness. The need for initial setup will imply a higher cost for the first-of-a-kind reactor project; and to become competitive, a fleet of reactors with a total capacity comparable to some of the nuclear power programmes in the West needs to be built.

However, the need for nuclear power to mitigate climate change has been recognised at the 2023 United Nations Climate Change Conference (COP28). During it, several major nuclear power countries have entered a ministerial declaration to triple global nuclear power capacity by 2050. It is hoped that this will provide the room needed for the SMRs to flourish.

This article is contributed by Ir Richard Fung with the coordination of the Nuclear Division.