Electrical Performance Study of Colored c-Si Building-Integrated PV Modules
Min Hsian Saw, Jai Prakash Singh, Yan Wang, Erik Birgersson, Yong Sheng Khoo
Abstract
Digital ceramic printing on glass is explored as a solution to “camouflage” crystalline silicon-based solar cells in order to improve the visual appearance of c-Si PV modules for building-integrated photovoltaics; however, printing on the front glass reduces the light transmittance and, thus, affects the module performance. By combining experiments and regression modeling, we quantify the effect of six different colors with varying print opacities on module electrical parameters under standard test conditions. Our experimental results reveal that print opacity and color have a significant detrimental impact on the module short-circuit current (Isc) and maximum module power (Pmpp), but minimally affects the module open-circuit voltage (Voc) and fill factor (FF). Taking black print with 100% opacity as an example, the monochromatic module shows 75% Isc-loss, 74% Pmpp-loss, 6% Voc-loss, and 5% FF-gain compared to a nonprinted glass. Furthermore, it is observed that at any given print opacity, black print results in the highest performance loss, whereas blue print shows the lowest loss. Our regression analysis shows that the effect of print opacity on module-Isc is color dependent. The fitted regression models for the six colors under study are able to predict the Isc-loss for any given opacity level with a root mean square error of less than 1%.