Evaluating the benefit of smart windows in retrofit of residential buildings in hot-humid area

This study evaluates the energy-saving potential, economic feasibility, and environmental impact of smart glazing in residential retrofits in China’s hot-humid regions. By comparing thermochromic glazing (TC) with electrochromic glazing (EC) under three different control strategies and incorporating measured occupant behavior data and future climate scenarios into energy modeling, the study explores the overall performance of smart glazing across various household behavior patterns and climatic conditions. Results indicate that the energy-saving benefits of smart glazing are highly sensitive to occupant presence patterns – households with longer occupancy durations experience greater energy savings and shorter payback periods. Additionally, the hotter the climate, the more pronounced the energy-saving and peak-load reduction effects of smart glazing, with median annual savings reaching up to 3500 kWh under the RCP8.5 2090 scenario. Although EC exhibits superior performance, its high cost and complex maintenance requirements may hinder large-scale adoption. This study highlights the importance of incorporating user behavior and climate adaptability in high-rise residential retrofits, offering scientific guidance for the optimal selection and regional deployment of smart window technologies.