A Study on Optimal ESS Discharging Scheduling to Reduce Seasonal Peak Demand in PV Power Plant

Energy Storage System (ESS) installed in photovoltaics (PV) power plants has been operated to alleviate the shortage of connection capacity and to reduce peak demand. Therefore, the REC weight of 5.0 was given until 2020 for the PV power output through the ESS charged at specified time (10:00-16:00) and discharged at other times (16:00 similar to). Meanwhile, the peak demand of this summer is occurring between 15:00 and 17:00 when the PV power output gradually decreases. However, the existing installed ESS is operated with a simple pattern that discharges from 17:00 to 24:00 with a fixed PCS output without considering seasonal peak demand. Therefore, this paper presents an ESS discharging scheduling that can respond to peak demand by introducing incentives. For irregular PV power output, the proposed ESS discharging scheduling is determined to maximize the expected total daily benefit of the PV power plant by applying k-means clustering and scenario techniques (sunny, cloudy, and rainy). As a result of the simulation, the ESS was discharged to the maximum during the winter peak time (09:00-10:00) and the expected total daily benefit increased by 10% compared to the previous one.

Automated summary

This study proposes an ESS discharging scheduling for photovoltaic power plants that can respond to seasonal peak demand. By introducing incentives, considering irregular photovoltaic power output, and applying clustering and scenario techniques, the scheduling aims to maximize the daily total benefit.