Monitoring manual control of electric lighting and blinds

This paper reviews, validates and extends present knowledge of the degree and kind of manual control strategies of blinds and electric lighting systems that are used in private and two-person offices. A new monitoring setup was applied from March to December 2000 in 10 daylit offices in Germany that featured manually operated electric lighting and automatically controlled external venetian blinds with manual override. The data shows that individuals consistently followed the same control strategy for their electric lighting and blinds. Groups of individuals tended to activate their electric lighting according to Hunt’s probability function, although there was a large spread between individual control levels. All subjects used their blinds to avoid direct sunlight above 50 W/m 2 , and incoming solar gains above 50 klux (~450 W/m 2 ). They also were more willing to accept automatic blind opening than closing.