A simulation tool for the operation of a hybrid PV/Wind plant coupled with a hydro-pumping storage (HPS) was built; it was used for simulating the behavior of such a system among an energy mix constituted by fuel oil generators and electrical cables in an insular electrical network. Each subsystem is modeled with a variable efficiency depending on the operating regime and on solar and wind sources variability. An optimization of the hydro-pumping system operation was developed using four reversible pumps in parallel. The objective is to shave the electrical peak demand in replacement of costly and polluting combustible turbines. An energy situation like the one in Corsica Island is considered and all the electrical productions are taken into account, not only renewables but also fuel and imported electrical energy. The covered part of the peak demand can reach 80% in an annual basis and the influence of the hybrid system characteristics on the performances were studied. Some hybrid systems configurations were highlighted. (C) 2017 Elsevier Ltd. All rights reserved.