Preliminary experimental evaluation of electrotropic windows in a full scale test facility

This paper reports the results of a preliminary study aimed to evaluate the visual performances of an electrotropic switchable glazing using a south oriented full scale experimental station. The internal daylight illuminance and luminance distribution acquired with electrotropic glazing in clear state have been compared with those in milk state. At the same time, quantities able to characterize the external weather conditions were measured. The results highlight that: (1) the milk state helps to prevent areas with high luminance peaks as well as to reduce the maximum luminance values at the observer’s eyes, (2) the milk state allows to increase illuminance values in the points farthest from the window and (3) in terms of mean luminance values of the window, there are no remarkable differences between glazing states.