Modelling and analysis of decentralized energy systems with photovoltaic, micro-hydro, battery and diesel technology for remote areas of Nepal

Abstract

Abstract Remote areas of Nepal suffer from limited or no access to electricity. Providing electricity access in remote areas is one of the foremost challenges of any developing country. The purpose of this study is to develop and propose a reliable and low-cost model for electrification. The study presents an optimized choice between decentralized renewable-energy systems and grid expansion. Opting for an analytical method for the modelling and analysis of electrification options based on life-cycle cost (LCC) and economic distance limit, each energy system for varied load conditions is compared for a better option. A framework for energy-system selection based on available resources is proposed. It compares the grid-expansion option with potential isolated renewable-energy systems to ensure energy access to the area under consideration. Additionally, off-grid configurations that rely on renewable energy sources are also considered for the necessity of backup supply to ensure continuous power to the research area. Techno-economic assessment is carried out for different off-grid and hybrid configurations proposed in this study and their feasibility checks are carefully examined. Commercial efficacy of the proposed hybrid energy systems is assessed by comparing the life cycle and energy cost and by performing different additional sensitivity analyses. The study concludes that reduced generation cost supports the increasing penetration of electrification. The LCC for grid expansion is the most economical under high-load conditions, whereas for the isolated and sparsely settled populations with low-load conditions, photovoltaic power backed up with a diesel generator is the most economical.