Sizing and location identification for an electrical energy storage system in a renewable microgrid

Abstract

Microgrids are proving themselves viable to address the need for more reliable renewable power systems. They can improve the resilience of the overall system in case of abnormal conditions. The city of Spokane in Washington, is considering establishing a microgrid using existing transmission and distribution infrastructure. This microgrid will be supplied solely from the existing hydroelectric generators and proposed photovoltaic installations. One of the challenges to overcome in a renewable microgrid is the availability of the renewable energy resources. As the hydro generation capability varies seasonally, solar energy varies both seasonally and over the course of a day, it is advantageous to include an energy storage system in the microgrid. This can compensate for variations, and improve the reliability of the microgrid. The main objective of this paper is to identify the energy storage system suitable for this specific microgrid and estimate its size while finding an ideal location to place it in the microgrid. The study system was simulated using Powerworld. Different techniques were evaluated to determine the size and location of the energy storage system.