N E W I N V E S T I G A T I O N O N T H E A P P L I C A T I O N S A N D C O M P U T E R S I M U L A T I O N O F P H O T O V O L T A I C C E L L S A N D S T O R A G E S Y S T E M S

A complete model is proposed as a tool to simulate and optimize photovoltaic cells and storage systems. The normalized form of the equations with respect to the battery capacity allows us to gen eralize its use for any type and size of batteries. The validity of t h is mo del t o represent t he bat t er y vo lt age evo lut io n dur ing charge, overcharge and discharge proces ses and to predict the per formance of solar systems under different operational conditions is analyzed. Moreover, the battery efficiency losses are presented as a function of the upper regulation thresholds of the charge controllers and the size of the ar ray and storage systems in a domestic application in the climate of Egypt