Correlating Partial Shading and Operating Conditions to the Performance of PV Panels

Abstract

Harvesting solar energy as a renewable source to meet the expanding energy demand is essential for sustainable growth and a greener planet. The performance of the photovoltaic panels is affected by factors such as partial shading, elevated temperature, mismatch between the cell parameters, etc., which contribute to the loss in an inter-correlated manner. In the current study, we isolate the contribution from each factor through experiments. The partial shading is configured through distributed paper chips in different patterns keeping the overall shaded area constant. The isolation of shading loss from the total loss allows us to find out the total contribution from the mismatch and temperature factors. In a further set of experiments, we isolate these two factors as well. We find that the major contribution comes from the shading loss. We also observe that not only the fraction of the partial shading but also the shading pattern has a crucial bearing on the panel performance. For equal fraction of the partial shading, the more distributed the shade, the less the loss. The next major contributor is the temperature loss for which we find out empirical formulae to predict the performance under different operating conditions. The overall effort is aimed at estimating the operational efficiency of the PV panels under soiled or partially shaded conditions.