Techno Economic Assessment of solar PV/wind and diesel generator hybrid off grid power systems for rural community

Abstract

Electrification to rural areas, those with no electric access or detached from national grid, is one of the most challenging issues in developing countries like Ethiopia. Due to the recent concerns about the global climatic change and diminishing fuel prices, searching for reliable, environmental friendly and renewable energy sources to satisfy the rising electrical energy demand has become vital. The main objective of this study was to obtain an optimal suited configuration of hybrid electricity generation system using various renewables/alternative energy sources to meet the village load requirement reliably, economically, continuously and sustainably. The solar potential and wind speed were taken from NASA, the cost of associated hybrid components are collected from different sources and the electric load data was estimated for community and public service’s needs. Hybrid Optimization Model for Electric Renewable (HOMER) was used to perform techno-economic analysis to meet the load requirement using solar PV-wind turbinediesel generator-battery hybrid off-grid configuration. Based on the resources, load, hybrid system and the component cost input data considered and running the simulation HOMER gives optimization, sensitivity and grid comparison results. The optimization result of the simulation demonstrates that the hybrid configuration (solar PVwind turbine-diesel generator-battery) that achieves total NPC of $1,506,689 and COE of 0.360$/kWh at a renewable fraction of 0.6 as the best optimal hybrid configuration considering economic and environmental point of view. From environmental stand point of view, the system is characterized with a minimum percentage of carbon dioxide and other GHG emission of about 195,974 kg/year. The sensitivity analysis examines the consistency of the optimal system under different sensitivity inputs such as load, wind speed, diesel price and PVcapital cost multiplier and it reveals that the multiple hybrid systems (PV-wind-generator-battery) system is more favorable. The grid comparison reveals that hybrid off-grid power generating systems is feasible for electrification of rural community beyond the 3.66 km breakeven grid extension distance. The selected hybrid configuration system is an excellent solution to guarantee a reliable and affordable electric power supply without interruption of the load for the village of Deleta when compared with grid extension under certain conditions of the high capital cost of grid-extension, sparsely populated and low energy demand of the rural community.