Choice of battery energy storage for a hybrid renewable energy system

There are certain unelectrified villages across the Indian subcontinent where providing supply through the grid is difficult due to forest cover or mountainous terrain. The most feasible option is to provide off-grid electrification through renewable energy resources such as solar or wind energy. These intermittent sources do not promise a 24 x 7 supply system. Thus, along with solar or wind energy systems, it becomes important to use a renewable resource, such as biomass, which is available in abundance in rural areas. The need for battery energy storage becomes mandatory in order to store the surplus energy produced by renewable resources and supply it at a time of insufficiency. Currently, many battery technologies are evolving with better characteristics than conventional battery systems in terms of efficiency, response time, deep cycle discharge, lifecycle, etc. The aim of this study is, firstly, to design and model a hybrid renewable energy system (HRES), using photovoltaic (PV)-Biogas (BG) system with HOMER software. Secondly, we aim to test this model using three different battery types: advanced lead acid (LA) batteries, lithium ion (LI) batteries, and zinc-bromine (Zn-Br) flow batteries (FB), used individually. Using these three battery technologies, the HRESs are then compared in terms of system sizing, economy, technical performance, and environmental stability. A case study for the unelectrified village of Madhya Pradesh (MP) is discussed to suggest the practical aspect of the comparative analysis. The results demonstrate that the HRES using LI batteries is the most favorable choice. Using this configuration, the economic parameters, including total net present cost (NPC) and levelized cost of energy (LCOE), are found to be lowest. The technical parameters, including battery state of charge (SOC), capacity shortage, and environmental parameters (CO2 emissions) are found to be optimum.