Optimal Sizing Strategy and Economic Analysis of PV-ESS for Demand Side Management

We propose a method to determine the optimal capacity of a photovoltaic generator (PV) and energy storage system (ESS) for demand side management (DSM) and review its economic revenues. The calculation procedure for determining the optimal capacity of PV-ESS is complicated because it includes the estimation of load and power generation patterns, selection of candidate capacities, simulation of PV-ESS operation, calculation of revenue and cost, economic analysis, and selection of optimal capacity. Therefore, we address and generalize the methods which are the entire procedure for selecting the optimal capacity of PV-ESS, the method for selecting the initial candidate capacity of PV-ESS and the method for selecting the optimal capacity of PV-ESS. In numerical simulation, we applied this methodology to four real industrial customers in South Korea. When we analyzed the optimal capacity results calculated for customers with different load patterns, the ESS c-rate differed depending on the load pattern. Under the simulation conditions, the economic efficiency tended to improve when there was a peak reduction, the ESS capacity was small, and the PV capacity was large. This is because the peak rate is high, and the cost of PV-ESS is expensive compared to the electricity rate. Under the current electricity rate and PV-ESS cost conditions, we determined the optimal capacity of PV-ESS for DSM of actual industrial customers. We confirmed that it is an effective method that can be applied generally.