Techno-economic analysis of off-grid PV-Diesel power generation system for rural electrification: A case study of Chilubi district in Zambia

The study explores the techno-economic feasibility and viability of a Photovoltaic-Diesel Hybrid system for rural electrification in sub-Sahara Africa with a case study of Chilubi island, a remote district without access to electricity in the Northern Province of Zambia. Using HOMER (Hybrid Optimization of Multiple Electric Renewables) Pro software, the best and most feasible technical solutions through different hybrid system configurations, combinations and the district's rate of access to electricity were considered based on the least Levelized Cost of Energy (LCoE) and life cycle costs of the project. The results show that operating diesel generators as stand-alone is not economically sustainable and has a high LCoE. Influencing factors include variability in diesel pump prices, high fuel transportation costs, high cost of operation and maintenance, among other factors of concern. 100% photovoltaic (PV) with a battery system gave the lowest LCoE. However, the initial capital cost of solar energy projects in Zambia is relatively high compared to the equivalent diesel-based plants, as shown herein. It explains why diesel power plants are favoured for off-grid settlements. On the hand, the low operational cost and LCoE of PV power plants favour rural districts as they offset the high initial capital costs. Additionally, the continued downward trend in the cost of PV installations per kWp has opened discussions among policymakers and energy planners in Zambia to favour rural electrification with renewable energy-based power generation. This study contributes to this discussion.