Daylighting Control Performance and Subject Responses to Electrochromic Windows in a Meeting Room

Electrochromic (EC) windows are installed in a window system testbed in Minhang, Shanghai which consists of two side-by-side meeting rooms. In one room, twelve EC windows with a visible transmittance Tv range of 0.01–0.59 were installed. In the other room, low-e glass windows with inside shade were installed as reference. Eight-four subjects worked in those two rooms. This study analysis subjects responses and physical data in the room with EC windows and compares it with them in the other room. The results show that light level control, color of the glass and glare control have strong and significantly positive correlation with overall satisfaction with EC windows. The rating in light level, feel of space luminance and glare sensation are significant difference between two rooms. EC windows in Room A did very well in control indoor glare, but reduced the indoor brightness.