Feasibility Analysis of Battery Energy Storage Systems in Nepal: A Techno-economic Case Study of Chanauli 33 kV Substation

Abstract

Nepal’s electricity system is dominated by RoR hydropower which leads to significant seasonal imbalances and transmission and distribution networks are also operating with congestion due to not having effective implementation of transmission and distribution expansion plan. Conventional grid reinforcement options such as line upgrading or new transmission construction has many limitations like high capital costs, long implementation periods and environmental and social challenges. In this scenario, Battery Energy Storage Systems (BESS) could be a promising alternative for enhancing grid flexibility and reliability. This study highlights a techno-economic analysis of BESS placement at the Chanauli 33/11 kV substation in Nepal. The analysis is based on actual hourly load data obtained from the Nepal Electricity Authority, projected load growth and transmission line loading limit. MATLAB based iterative optimization approach is used to determine BESS Size and capacity considering operational constraints and battery degradation over a 2 year planning horizon. The results demonstrated that BESS with rated capacity of 1.9 MW / 9.1 MWh is sufficient enough to mitigate projected summer peak overloads through effective peak shaving within depth of discharge and state of charge design limits.