Small modular reactors for nuclear-renewable synergies: Prospects and impediments

Conventional energy systems in both developed and developing economies are currently run by fossil-fueled power plants. Many of them are ageing and are now being considered for the replacement to reduce the carbon intensity in electricity generation. One of the main routes to achieve this goal is by scaling-up the deployment of the renewable energy system (RES). However, the increasing share of variable RES tends to affect the electrical grid operation. Hence, the need for reliable and flexible energy sources has emerged to cope with the variability in electricity and energy markets. Small modular reactors (SMRs) are emerging as alternatives to baseload fossil fuel systems and retiring large nuclear plants, primarily due to their small capacity and less-capital intensive characteristics. The intermittency of power generation in the grid with a higher share of RES can be coped with in synergetic and effective way by adopting SMRs that form a nuclear-renewable synergy in fulfilling the electricity demand. Furthermore, SMRs are designed to operate in load-following mode adjusting the power output as demand of electricity fluctuates. SMRs feature modularity intended to enable enhanced constructability and phased-deployment, adapting to the increased share of renewable energy in a distributed energy system, as energy demand increases. This paper will highlight the main outcomes of miscellaneous recent studies on the integrated energy systems carried out by international experts under the aegis of the International Atomic Energy Agency. The final publication of the study discusses the potential synergy of SMRs with RES for electric power production, as well as for other clean-energy applications including seawater desalination, district heating, and hydrogen production.