Longer battery lifetime provided by a priority load control algorithm on stand-alone photovoltaic system

Access to electricity has a positive impact on the socio-economic activity in rural livelihoods. Stand-alone photovoltaic (SAPV) systems are the most popular PV application for rural electrification in areas nonconnected to the grid, but it is still relatively expensive. Batteries are considered as a weak component of the system, comprising an important part of the total cost and are usually replaced multiple times during PV system lifetime. A priority load control algorithm has been developed in order to gain a better energy management over system loads and the battery storage, and therefore guarantee the energy supply for critical loads and extends the battery service lifetime. This will increase the reliability of the system and the end-user satisfaction. This article describes a stand-alone PV system model used for the development of a priority load control algorithm and explains and implements the algorithm. The results of several test scenario simulations are shown and discussed.