Small to medium sized battery storage required to address the intermittency challenge of the energy of solar radiation could be achieved by appropriate sizing of the photovoltaic system parameters like photovoltaic module (PVM) number and battery capacity. This paper presents the results of evaluation of the optimum parameter values in sizing of stand-alone photovoltaic (PV) system that satisfies building energy demand, with almost zero Loss of Power Supply Probability (LPSP). A time step simulation of system performance based on energy balance for various combinations of PV numbers and battery capacities was employed. (Three seasons of operation were considered; rainy, hot and hot/dry). The rainy season result indicating high storage capacity requirement of about (2500-Ah), is of highest cost compared to other seasons. Stand-alone photovoltaic system size that will assuage the intermittency challenge; mitigate peak demand costs and provide near zero LPSP was determined. Keywords: loss of power supply probability, photovoltaic, energy demand, parameter sizing, stand-alon
