In most isolated regions, the diesel generator is the main source of electrical power. The price of the extension of the electrical network for these regions is difficult and costly. These regions suffer from the fuel supply and its high cost, which drastically increases their isolation. In this context, the integration of one or more renewable energy sources can have a beneficial impact on the production of electrical energy, in terms of cost and availability. However, improvements in the design and operation are always necessary to make this technology more competitive in isolated regions. The objective of this work is elaborate of models in view to the sizing of hybrid photovoltaic-wind energy system with storage, to reach this stage of sizing we treat all system parts photovoltaic, wind and diesel; for each subsystem a detailed model was developed followed by validation in the PSIM environment. To maximize the performance of renewable energy systems it is necessary to track the maximum power point MPPT. The sizing of a hybrid system using Homer software is also treated in this work.