Energy storage systems and distribution grids: A real case study in Italy

The present paper deals with the topic of the integration of Energy Storage Systems (ESSs) in Medium Voltage (MV) distribution grids, managed by Distribution System Operators (DSOs), in case of significant presence of Dispersed Generation (DG), typically based on Renewable Energy Sources (RESs). A real case of installation of a Li-Ion Batteries ESS, by the Italian DSO Enel Distribuzione, in a High Voltage (HV) / Medium Voltage (MV) station in the Italian power system, has been object of study. For this purpose, a MatLab software, made up of more tools, has been implemented. It allows interfacing a proprietary database of Enel Distribuzione to MatPower tool and performing multi-period Power Flow (PF) analyses. The software has been used to evaluate the performance of the real ESS in the real MV grid, for active power peak shaving and reactive power compensation functions, in respect to the HV grid. With a critical analysis of the results, the effectiveness of the installation of the ESS on the real network has been tested.