In this paper, we present a Stand-alone Power system (SPS). The goal of this system is the ensuring of the electricity production without interruption in remote areas. It consists generally of a five components which are a solar energy, an energy storage that combines a water electrolyze and a storage gas tank, an energy conversion based on a proton exchange membrane fuel cell (PEMFC), an ultra-capacitor storage (UCap) and a suitable energy management unit to manage and to supervise the system operation of the hybrid system. This combination can ensure the optimal behavior of the load with the respect of the slow dynamics of the PEMFC. The integration UCap ensures the elimination of the slow dynamics of the PEMFC during the transient event. A Novel supervisory command is proposed. The modeling of the overall system is given and the obtained results are presented and discussed.