| Keywords |
Daylight dimming control ; Perimeter zone ; Office ; Radiance ; Lighting energy savings ; Prediction model ; Correlation |
| Abstract |
This study examines the application of a daylight dimming control system to four perimeter zones in openplan office space. Computer simulations using Radiance were performed for each space under overcast sky conditions. Results indicate that the differences between maximum and minimum daylight illuminance on desktop ranged from 30.9 lx to 79.8 lx due to the effect of sky surface under overcast sky. The differences at photosensor illuminances varied from 95.2 lx to 175.3 lx. Overall, insufficient light output was provided by lighting fixtures in all zones and a target illuminance was not achieved. The control system applied under overcast sky succeeded to provide 600 lx of desktop illuminance. In this case, the lighting energy savings ranged from 32.76% to 68.93%. Prediction models indicate that strong linear correlations existed between desktop illuminances and desktop illuminances by daylight. The coefficients of determination for the models ranged from 0.8693 to 0.9625. The models were effective under the significance level of 0.01. |