An option for the integration of solar photovoltaics into small nuclear power plant with thermal energy storage

Abstract This paper is concerned with a concept for integration of solar photovoltaics into a small nuclear power plant. The photovoltaic electricity is firstly converted into heat that subsequently is used for nuclear steam superheating. The hybrid plant is equipped with thermal energy storage. The storage technology under evaluation in this study is borrowed by the concentrated solar power plants. When photovoltaic electricity is available, electric heaters heat molten salts. The steam that is generated in a small modular nuclear reactor is heated with hot molten salts in the external superheater. The hybrid plants and its PV section are modelled and simulated with appropriate software tools. As a result of the higher turbine inlet temperature, the hybrid configuration is more efficient than ordinary NPP. The efficiency of the hybrid nuclear plant can be considerably increased up to the effectiveness level of the modern thermal power plants. The additional power generated by the PV-nuclear plant is approaching the capacity of the standalone NPP. The integrated thermal storage acts as indirect and large electricity storage. Regarding round-trip efficiency and installation costs it surpasses compressed air storage and is competitive with the pumped hydro storage in the absence their geographical and environmental constraints.