Optimization of a reliable grid-connected PV-based power plant with/without energy storage system by a heuristic approach

•A grid-connected photovoltaic power plant is optimized.•Portion of purchased power and area of the installed photovoltaic are optimized.•The effect of the electricity price is modelled and studied on the results.•When the electricity price increases, use of PV system is more beneficial.

Accurate and consistent evaluations of PV system performance are critical for the continuing development of the PV industry. This paper focuses on optimization of a grid-connected PV-based power plant. For this aim, the portion of the purchased power from the utility grid and the area of the installed PV system are optimized in order to have a cost-effective and reliable energy system. The optimization problem is solved with/without consideration of the storage system. Since it is expected that the electricity price is increased during the coming years, the optimization of the grid-connected PV-based power plant is done in different electricity prices. The goal of the optimization problem is to minimize the net present value (NPV) of the system subject to the reliability constraint which is defined by the loss of power supply probability (LPSP). Harmony search which is an easy to implement and efficient heuristic algorithm has been used for solving the optimization problem. Simulation results reveal that at the current electricity price of Iran, it is not beneficial to use PV system. However, when the electricity price increases, there is a point at which investment in PV system will be cost-effective.