Investigating the Value of Energy Storage Systems on a Utility Distribution Network

Abstract

South African’s own monopoly utility company is experiencing huge energy crises, and this directly affects both consumers the indigent and the privileged. Therefore, radical action must be taken to consider diverse alternative energy sources. This paper presents a method used in modelling and simulating an Energy Storage System (ESS) for an industrial customer connected on a Utility Distribution Network. This paper used Digsilent Power Factory simulation software. The functionality used of the software was the Quasi-Dynamic Simulation Language (QDSL). Furthermore, the programmable logic enables the author to define how the energy storage system operates, including setting limits and measurements that are calculated autonomously. A simple example is the coding of how the State of Charge (SOC) of the battery is determined, including the charging/discharging operation status of the battery and how it should behave. This paper analysed the existing network and identified network violations and constraints and proposed the Energy Storage System (BESS and FC) as the preferred solution. Moreover, to exploit the benefits offered by the energy storage sources when working in parallel. These benefits include peak shaving, reducing electrical line losses, maintaining balanced voltage levels and the desired fault levels. The purpose of this study was to evaluate the value of energy storage for an industrial customer by seeking to achieve the following: alleviating thermal loading on transformers, achieve peak shaving, reducing electrical losses and operating the network within the voltage limits.