Study on the impact of window shades’ physical characteristics and opening modes on air conditioning energy consumption in China

•A shading schedule of residential buildings is obtained through 949 questionnaires.•Two opening modes of window shades were considered.•Analyzed the six physical characteristics of window shades on energy consumption.•The results could allow design guidelines for developing the performance of window shades. This paper focused on the impact of window shades’ physical characteristics and opening modes on annual air conditioning energy consumption of residential buildings in China. Three building models with different window layouts were proposed initially, and then validated by the dimensionless indicator annual energy performance (AEP) to determine the final building model adopted in this study. Harbin, Beijing, Guangzhou, Changsha and Kunming were selected to represent five different climate zones in China. The shading model has taken six physical characteristics of window shades, viz. outer emissivity, inner emissivity, solar transmittance, solar reflectance, thermal infrared transmittance, conductivity and two opening modes, viz. up & down mode as well as left & right mode, into consideration. Besides, the window shades operation schedule was summarized through 949 valid questionnaires. The annual air conditioning energy consumption was calculated via EnergyPlus software, and then the impact of the above different opening modes and parameters on energy use were investigated. The analysis results indicated that the top & bottom opening mode is better than the left & right mode when used in Harbin, and the effect of two different modes in air conditioning energy consumption in Kunming is similar. But in the other three cities, the left and right mode is preferred. Besides, the analysis results of the impact of different physical characteristics on air conditioning energy use in different climate zones could help improve the energy performance of window shades.