Development of an economical model for a hybrid system of grid, PV and Energy Storage Systems

Major concerns associated with renewable energy resources are uncertainty and unpredictability. Energy Storage Systems (ESSs) can help create more reliable and dispatchable systems by adjusting charging and discharging time and rate. In this study, an economic model is developed for a hybrid system of grid-connected solar photovoltaic (PV), Compressed Air Energy Storage (CAES), and batteries. PV generation depends on solar irradiance. CAES can store energy in large amounts and for longer periods and at lower cost than other storage systems. Batteries are integrated with CAES in the developed model mainly to operate for lower demand and shorter periods. Optimal planning for generation and storage is derived based on the developed model for each day using Dynamic Programming (DP) or simulation methods. The original non-linear model of the system is converted to a linear model in this study. The results of the model are different for each period and are highly dependent on the load demand.