LBNL Report Number
This paper discusses the unique features of a multistory office building that successfully permit most of the space to be daylighted and the electric lights to be dimmed by a cost-effective centralized system. This system includes: the use of light shelves, sloped ceilings, and proper building orientation and symmetry, and supplies only the ambient illumination. Measurements of the daylight illumination levels and the performance of the lighting control system indicate that daylighting can provide over 70% of the required ambient illumination through the year. Based on the installed cost of the lighting control system, its payback period is 2.21 years.