Design and modelling of PV power plant for rural electrification in Kayonza, Rwanda

Abstract

An off-grid Solar Photovoltaic system is an effective option to solve the power supply problem for rural and detached areas from the national grid. Electrical energy from solar radiation indicates that various combination of components with storage system as backup of system are being used. In this thesis, PV modules, inverter, Charge controller and Batteries have been designed, reproduced/simulated and optimized for the rural area of Rwisirabo village in Kayonza district, eastern province of Rwanda. There is no any tracking system considered in this work. Based on the load assessment and the design of SPV system, primary AC load of village were 551.718 kWh/day with peak load of 85.10 kW, deferrable load was about 9.99 kWh/day and deferrable peak load of 2.00 kW with COE $0.200/kWh were involved during optimization of the power plant. To model and simulate the most favorable off-grid system the HOMER software has been used. Electrical energy from SPV power plant supply power directly to the Ac load and the storage battery charged when there were excess energy production from PV panels. However, either in peak load time or low generation storage batteries are discharged so that load remain connected to the power electricity. The load has been suggested for households, small businesses, secondary school, health post, police post, community church and deferrable load as water pumping. During designing and sizing of this SPV, the simulation and optimization was carried out based on the daily consumption, weather parameters like solar irradiance and temperature, economics of integrated system elements and other parameters in which the total Net Present Cost and Levelized COE have to be minimized to select economically feasible and technically capable solar PV power plant. The data from design is used for simulation as input of HOMER software to figure out the total energy production per year. There is no any tracking system considered in simulating and modelling this SPV power plant.