Design of a Stand-Alone Residential Solar Power System: An Integrated Computational Methodology and a Case Study

Abstract

This paper presents a sequential method for sizing a stand-alone photovoltaic (PV) system that supplies the full electrical demand of a residential house. The method computes the daily energy demand, applies a loss margin, and then determines the PV array power, the battery bank capacity, the charge controller current rating, and the inverter power rating. The method is applied to a house with a daily demand of 1160 Wh, a 24 V DC bus, and a design autonomy of two cloudy days. The results give a PV array of 400 W (two 200 W modules), a battery bank of 24 V / 200 Ah formed by two 12 V / 200 Ah batteries in series, a 25 A MPPT charge controller, and a 300 W pure sine wave inverter. The paper also examines how sensitive the result is to peak sun hours, depth of discharge, and load growth, and it states the limits of the calculation, which does not replace a complete design to the applicable standards or field validation.