Modelling the Performance of Simple Off-Grid PV Systems

27th European Photovoltaic Solar Energy Conference and Exhibition; 4254-4259 A new model is presented for the detailed simulation of a simple off-grid PV system with battery storage. The model is based on detailed laboratory measurements of the performance of the module and battery combined with a mathematical model for the interaction between the module and battery under varying conditions of irradiance and temperature. The model has been validated against experimental data on a small PV-battery system with a power load, with results showing that the model is able to predict the total energy delivered to the load with an error of <2.5%. The model has been implemented in GIS software to make it possible to apply it to large geographical areas. A study for Africa is presented, calculating the optimum size of PV module and battery for a given desired energy consumption and maximum reliability of power availability. The model will be implemented in the PVGIS web application for PV performance estimation.