The duck curve phenomenon is a grid challenge observed with high solar energy integration, against the daily electricity demand curve’s shape. However, as solar installations grow, it could become a concern for grid operators for maintaining stability and economic dispatch. This paper utilizes dynamic optimization workflow offered by Modelon Impact to size the Battery based energy storage (BESS) for mitigating the duck curve. Optimization is applied on a system level simulation model of Mumbai power system where the battery capacity is a degree of freedom with photovoltaic penetrations. The model then optimizes the operation of Indian grid, effectively mitigating the duck curve, and calculates the optimal size of the battery.