Multi-zone control of daylight-responsive lighting control systems

Open Access
Author:
Subramaniam, Sarith
Graduate Program:
Architectural Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
December 04, 2013
Committee Members:
  • Richard George Mistrick, Thesis Advisor
Keywords:
  • Daylighting
  • Lighting control systems
  • Energy
  • Illumination
Abstract:
Daylight responsive lighting control systems are employed to optimize the use of electric lighting in a daylit space. Although the potential of daylight-responsive lighting controls systems is widely acknowledged, the present-day performance of such systems is far from optimized. Several studies have reported discrepancies between their promised and actual performance. Most contemporary daylight-responsive lighting control systems, whether based on switching or dimming control, are single-zone systems. While single-zone systems may perform satisfactorily in small spaces, expanding their scope to spaces with large spatial depth results in an uneconomical expenditure of electric energy. This thesis examines the potential of multi-zone control for improving the performance of daylight-responsive dimming systems. Preliminary studies conducted on multi-zone systems focused on investigating the performance of such systems in optimized conditions. The optimized control algorithms for multi-zone systems demonstrated up to 14% greater energy savings than the optimized algorithms for single-zone system. A sequentially optimized multi-zone algorithm was developed on the basis of the dimming trends observed with a fully optimized multi-zone algorithm. The savings obtained through the sequential algorithm were comparable to those obtained through a fully optimized algorithm. The performance of the multi-zone sequential algorithm was compared to that of a conventional single-zone algorithm in a quasi-real world application where workplane-based photosensors were used to dim electric lighting in a daylit room. The application of a multi-zone sequential algorithm provided up to 14% greater annual energy savings than the single-zone algorithm. The accuracy of both single and multi-zone algorithms was shown to be dependent on the quantity and positioning of workplane-based photosensors. The author recommends further research to comprehensively evaluate the potential of multi-zone systems and their application to real-world dimming systems.