Grid-connected photovoltaics prosumers to support smart city development in Rwanda: A case study for Ayabaraya Village

Abstract

Access to electricity is among the important targets in Rwanda as in other regions. The grid-connected photovoltaic (PV) prosumers market segment can contribute to the rate of access to electricity in Rwanda. Grid connected PV prosumers contribute in not only increasing electricity generation capacity but also producing affordable and reliable electrical energy. Therefore, the current research analyzes the possibilities of interconnection of small-scale prosumers with a national grid. In addition, the bidirectional flow of electricity either from prosumer grid and vice versa, aiming at monitoring the continuous power supply of the load is analyzed. The study is conducted in Ayabaraya village in Rwanda and the load profile for residential, commercial and industrial prosumers are analyzed. In this research, meteorological data from Photovoltaic Geographical Information System (PVGIS) up to 2016 is used to give global horizontal irradiation and ambient temperature. The amount of energy imported from and exported to the grid is determined by the connected appliances, the capacity of the PV system, and the amount of available irradiance at the time. The Home Energy Management System (HEMS), inverter control strategies, and prosumer load types are considered. The simulation reveals that available irradiance less than 30W/m2 at a time is below the grid-tie inverter's threshold power thus, the prosumer imports electricity from the grid. At irradiance larger than 30W/m2, the prosumer may optimize self-consumption and injects the surplus into grid.