Design and feasibility analysis of an off-grid hybrid energy system to fulfill electricity and freshwater demand: a case study

The stand-alone hybrid renewable energy system has emerged as a promising route toward reliable and sustainable electrification of isolated islands where grid power cannot be supplied due to techno-economic limitations. In this regard, this article focuses on the design of a system with renewable energy sources and storage facilities to meet the need for freshwater and electricity on Kavaratti Island, Lakshadweep, India. The principal objective of the research is to decrease reliance on the expensive and ecologically detrimental diesel generator (DIG) with the installation of solar-photovoltaic (SPV), wind-energy system (WES), battery-bank (BB), and fuel-cell (FC). In compliance with the Indian government's recent proposal to build desalination plants (DP) to satisfy the freshwater demands of the islands, this study considers the power consumption of DP. The stochastic load demand of electric vehicle (EV) charging stations is also taken into consideration. Moreover, considering all scenarios that might occur in a real-world system, a smart energy scheduling technique is suggested to maintain energy balance. Furthermore, five different planning configurations are analyzed in detail to identify the most desirable one. The hybrid SPV/WES/BB/FC/DIG system with 1815 kW SPV, 2288 kW WES, 1400 kWh BB, 781 kW FC, and 1003 kW DIG is obtained as the optimal configuration. According to research findings, this system has a cost of energy of 0. 186 /kWh, net present cost of 2. 68 × 108, and pollutants emission of 53, 902. 7 tons, which are 80. 11%, 76. 89%, and 79. 14% less than the DIG-only system, respectively. Furthermore, dump energy is found to be the lowest when both BB and FC are installed together, which highlights the importance of combining storage elements to maximize the utilization of renewable energy. Overall, the proposed study recommends LED to design a hybrid energy system with renewable energy sources and storage elements to make considerable financial gains and preserve the ecological diversity of the island.