In autonomous islands, the wind penetration is restricted due to technical reasons related with the safe operation of the electrical systems. The combined use of wind power with pumped storage (WPS) systems is considered as a means to exploit the abundant wind potential, increase the wind installed capacity and substitute conventional peak supply. An approach for the simulation of the autonomous electrical systems is proposed and applied in three islands. The simulation is based on the non-dynamic analysis of the electrical system, in order to calculate the energy contribution of the different power units. The aim is to analyse the prospects of WPS systems to decrease the electrical system's cost. The results show that the integration of WPS in autonomous islands may decrease the system's electricity production cost.