Field-performance of daylight-linked lighting controls and window blinds: a pilot study

Anca D. Galasiu and Morad R. Atif, National Research Council Canada, Canada

Keywords

daylighting, lighting controls, window blinds, lighting, energy savings, dimming, automatic on/off, office buildings, monitoring, measured performance, daylight-linked control systems, photocontrolled lighting

Abstract

This paper presents the monitoring results of a field experiment conducted over the course of one year in two side-by-side occupied offices to investigate the impact of various configurations of manually-operated venetian blinds on the performance of a commercial photocontrolled continuous dimming lighting control system. The performance indicators considered were the electric energy consumption and the space illumination as a function of blind slat angle and retraction area. The results showed that under clear sky and with no blinds the lighting control system reduced the lighting consumption on average by 50 to 60 % when compared to lights fully on from 6 AM to 6 PM. These savings were however, reduced by 5 to 45 % based on the window blinds’ configuration tested. The impact of the blinds on the lighting consumption depended greatly on the variability of daylight levels and the sky condition and did not vary significantly from one season to another.