Modelling and Optimized Placement of a Grid Scale Energy Storage System Based on Li-ion Batteries for the Kenyan Grid

Abstract

Grid Scale Energy Storage (GSES) is attracting significant attention in the electrical power investment sector. While we have an understanding of the technical and economic limits of Renewable Energy Sources (RES) integration, such an understanding is limited with GSES, more so on the Kenyan grid. This study aimed at deepening knowledge on the potential benefits of GSES particularly arbitrage and peaking capacity. The study modelled the Kenyan grid based on the IEEE 14-Bus system and applied load flow analysis, simulation tools (on DigSilent Power Factory) together with analysis for different test cases to equip policy makers, regulators and investors on the technical and economic limits of GSES and also the interaction between GSES and grids integrated with RES. From analysis and simulation, specific knowledge was gained on where to optimally place grid-scale Battery Energy Storage Systems (BESS) in Kenya that was based on the Lithium-Ion chemistry. For best results, the Li-Ion BESS was optimally placed on the 33kV distribution buses of the 4 regions in Kenya: Nairobi, West, Mt. Kenya and Coast Regions. Further, the potential for Arbitrage and Peaking Service Provision was demonstrated and both were found viable, having an ROI of 109.35% and 104.51% respectively on the Kenyan grid. Other consequential benefits of having the BESS on the Kenyan grid were: the possibility of having the BESS act as spinning reserve and the de-loading of lines that are highly loaded at peak times.