Design and optimization of an off-grid integrated renewable energy system for remote rural electrification in India

This study aims to design the best off-grid integrated renewable energy (IRE) system for the electrification of twelve villages located in the Munsyari Block of district Pithoragarh, Uttarakhand state (India). Three off-grid IRE systems consisting of a solar photovoltaic (SPV) system/micro-hydro power (MHP)/biogas generator (BGG) and various battery energy storage (BES) devices like Lead-Acid (LA), Lithium-Ion (Li-Ion), and Sodium-Sulfur (NAS) have been proposed and optimized on the MATLAB to meet 8760-hour load demand. According to the simulation results, the total life cycle cost (LCC) and cost of energy (COE) of the SPV/MHP/BGG/NAS (base case) are INR 68.77 million and 16.77 INR/kWh, respectively. It offers approximately 20% and 100% lower LCCs than LA and Li-Ion battery-based IRE systems, respectively. The proposed system includes 676 SPV panels (NSPV), 648 BES devices (NBES), micro-hydro power of 25 kW capacity, biogas generator of 40 kW capacity, and power converter of 114 kW. Furthermore, the performance of the IRE system was evaluated by taking into account the load-resource associated uncertainties, and it was discovered that the LCC, COE, NSPV, NBES, and excess energy are increased by approximately 66%, 75%, 17%, 318%, and 373%, respectively, when compared to the base case. Finally, the sensitivity analysis has been conducted with the variable input parameters, such as inflation rate, discount rate, solar radiation, and dung collection efficiency. It is found that the variation in inflation rate significantly reduces the system LCC by 21.81 million INR. Whereas, variation in discount rate significantly increases the system COE by 5.72 INR/kWh.