Unpredicted and intermittent nature of renewable energy makes them difficult for grid integration and operation. Battery storage systems have thus been indispensable in rendering these systems dispatchable by improving their reliability and quality. Hybrid renewable energy systems combining the wind and solar power generation are rapidly gaining popularity due to the complementary nature of the respective natural energy sources. This study attempts to propose a sizing of Vanadium Redox flow battery based on min-max dispatch method while considering peak demand periods in a power grid. Further exploration of battery performance studied by observing its State-of-Charge shows an effective utilization of battery capacity and improved cycle periods for an extended cell life. © 2015 IEEE.