DEVELOPING A DYNAMIC ENVELOPE LIGHTING CONTROL-SYSTEM WITH FIELD-MEASUREMENTS/

The feasibility of an intelligent venetian blind/lighting control syst em was tested in a 1:3 scale model outdoors under variable sun and sky conditions. The control algorithm, direct sun block, and meeting the design workplane illuminance level, was implemented using commercially available and custom designed blind and lighting systems hardware. Wh ile blocking direct sunlight, the blinds were properly controlled to m aintain the design workplane illuminance within a tolerance of -10 per cent, +25 percent when there was sufficient daylight. When daylight le vels alone were inadequate, the electric lighting control system maint ained the design workplane illuminance. The electric lighting could be turned off if a user-specified time period at minimum power was excee ded. Lighting energy savings of 51-71 percent (southwest) and 37-75 pe rcent (south) were attained for the period from 8:00 to 17:00 on clear sunny days, compared to a fixed, partially closed blind with the same lighting system. Practical details for implementation and commissioni ng are discussed. The impact of control variations such as profile ang le, time step interval, and control area on energy demand is investiga ted.