Experimental investigations of a 1 kW solar photovoltaic plant in standalone and grid mode at different loading conditions

Abstract

Decentralized energy generation at community level is the need of the hour for meeting the increasing load demands. A pilot-scale 1 kW photovoltaic (PV) system was installed at Auniati Satra near IIT Guwahati for studying the effects of its operating parameters at different loading conditions corresponding to the environmental conditions prevalent in Guwahati, Assam (India). The PV system was subjected to constant electrical load both in standalone mode and grid-connected mode during the daytime at eight different loading conditions viz. 20%, 30%, 40%, 45%, 50%, 60%, 70% and 80% and half-hourly data of different parameters like solar insolation, PV energy, PV charge, temperature, and battery capacity were analysed. Optimum loading condition in standalone mode was found to be at 45% − 50% load under normal solar insolation without much burden on the battery bank and can be extended to a maximum load of 70% during the daytime at high solar insolation. In grid-connected mode, load application upto 45% was economically beneficial as less power was utilized from local grid. Though it can be subjected to almost its full rated capacity with input from the ac supply.