Evaluation and analysis of transmitted daylight color quality for different colored semi-transparent PV glazing

Abstract

Windows are one of the minor energy-efficient building elements, and PV windows can replace conventional windows to improve building energy performance. This study explored the color quality of transmitted light from 24 types of semi-transparent PV glazing, considering the color rendering index (CRI-Ra), gamut index (Rg), color fidelity index (Rf), and correlated color temperature (CCT). PV glazing in this study had four different transparencies (i.e., 20 %, 40 %, 60 % and 80 %) and six colors. The results indicate that different transparencies have little impact on the color quality of the transmitted light, but there are variations in PV glazing with different colors. PV glazing with different colors Ra ranging from 48.5 to 98.1, Rf ranging from 0.9 to 98.4, Rg ranging from 76.4 to 170.8, and CCT ranging from 1036.8 to 7948.8 K. This study summarized the feasible application scenarios of different colored semi-transparent PV glazing from indoor visual activities and human-centric point of view. The energy savings of PV glazing ranged from −43.88 % to 35.55 % in five climate zones in China. Lower PV transmittance leads to higher building energy consumption. The most energy-efficient PV glazing is PV-Regular 40 %, and the least is PV-Green 20 %.