In the last years, the electricity system has been subject to a paradigm change, due to increasing share of installed renewable energy sources-based power plants. This fact is leading electrical system-which proper operation was however affected by the intermittent nature of renewables-to become more "green". The union of energy chain de-carbonization with service reliability opens new opportunities for storage systems, although their relatively high cost highlighted the importance of optimal decisions in sizing, placing and operation of such systems. For addressing these aspects, appropriate mathematical models and optimization methods are needed: in this paper, a novel and efficient hybrid optimization algorithm is introduced, to solve i) sizing, ii) placement and iii) operation of arbitrary storage systems. This method is then applied to a low voltage grid, to demonstrate the effectiveness of the proposed methodology.