The goal of this thesis is to model and evaluate the dynamic behaviour and performances of a power-to-power (P2P) energy storage system installed in remote area, where there is no connection with the electrical grid and power is supplied by renewable energy sources (RES). The model has been developed in MATLAB-Simulink® environment, starting from single components and then constructing the whole system, also introducing control strategies. Single component models have been developed relying on an extensive research in literature, studying mass and energy balance equations, in addition to mass transport, thermal, electrical and electrochemical phenomena. The modelled system is composed by a proton exchange membrane water electrolyzer (PEMWE), a pressurized hydrogen storage tank, a proton exchange membrane fuel cell (PEMFC).