A novel management strategy for Electric Vehicles (EVs) storage systems is proposed in this paper. It aims to enhance the Renewable Energy Sources (RES) exploitation hour by hour, but prioritizing the EV mobility requirements. A mathematical modelling of the mobility system is firstly developed in order to estimate, hour by hour, the amount of EVs available to exchange energy with the electric grid, together with the average state of charge of their corresponding batteries. Then, a management strategy is properly introduced in order to increase the RES hourly energy production as much as possible, providing ancillary services too. The proposed management system is properly validated by means of a simulation study referred to a weakly interconnected power system, which is characterized by a strong RES penetration level too. The simulation results highlight the effectiveness of the proposed management strategy and the potentiality of the EVs storage systems in enhancing the RES exploitation.