Water cooled lithium lead balance of plant indirectly coupled with power conversion system operated with small energy storage in EU DEMO

European DEMOnstration fusion power plant (EU-DEMO) has the main goal of demonstrating the possibility of producing hundreds of MWe of electrical power from fusion by the end of the century. In this sense an important role is played by the Balance of Plant (BoP). BoP includes, at least, the Power Conversion System (PCS) that converts thermal power into electricity. PCS is thermally connected to the Primary Heat Transfer System (PHTS) which collects the thermal power generated in the reactor. In case of DEMO equipped by a Water Cooled Lithium Lead Breeding Blanket (WCLL BB), three different architectures of BoP are under development. In this work will be analyzed the Indirect BoP architecture, so called ICD (Indirect Concept Design) PCS, characterized by an Intermediate Heat Transport System (IHTS) installed between PHTS and PCS and equipped with a Small Energy Storage (molten salt) to operate, during Dwell, the Steam Turbine at around 10 % nominal steam load, as in the reference cycle. In this work it will be highlighted: i) the PCS layout and the relative Heat&Mass balance, ii) the cycle performance analysis and iii) the performance comparison with the other "pulsed" PCS architectures above mentioned. Some hints on the concept design of the interfacing Intermediate Heat Transfer Circuit with Small Energy Storage will be also provided.