Sizing of A Hybrid Solar PV-Wind-Fuel Cell Power System for Isolated Location

Abstract

At 23%, Rwanda electrification rate is still very low. Most of remote and rural areas are not connected to the grid network due to the insufficient power production and high capital cost for grid network extension. A large number of the population living in rural areas uses diesel generators to provide energy for different services, whereas an even greater number are still living without electricity. This strongly affects the provision of fundamental services such as education, social services and economic services. Many of these areas continue to experience low rates of development and livelihood improvement. In order, to change this trend, renewable off-grid power systems are a suitable option for the provision of a solution to institutions located in these regions with a sustainable, affordable and environment benefits. This research was focused on the sizing of the fully-renewable hybrid power system (solar PV-wind and fuel cell) for a high school, (Groupe scolaire Mukondo) located in Rubavu district in the western province. The system sizing was based on climatic data of Rubavu district given by the Rwanda Meteorology Agency. The goal was to meet the electricity demand load of the school, while taking into consideration the environmental effects. The system sizing of the school was divided into two cases. The first case considered the present situation for which the school is not boarding and has no laboratory facilities. For this case, the primary load demand of 21kWh/day with a peak load of 91kW is considered. The second considered case, proposed the future of the school with laboratories, and where the primary load was calculated at 102kWh/day with a peak load of 15kW. Solar and wind resources were considered to power the demand with a share of 60% and 30% respectively. The fuel cell was used as a backup system for excess energy production to be used later when the demand goes high or when there no power production by the primary source. HOMER software was used to size the system. After the data simulation, a system of 8kW PV system, 4 wind turbines and 1kW of fuel cell was proposed for the first case, and for the second case, a 12kW PV system, 9 wind turbines and 1kW system was proposed.