The supplied energy from these resources is predictable and as a result the power of these power plants and their storage systems will be considered much more than the amount of load power demand, to increase load reliability and availability. In hybrid systems, the generation predictability with combining the several resources is increased and in fact these resources cover each other’s deficits. From this perspective wind and the sun have presented suitable overlap for each other, so the power of units and also necessary storages in combining wind-sun units compared to only wind unites or sun units have been significantly reduced.