Fifty percent energy savings with automatic lighting controls

An electronically ballasted lighting control system was demonstrated at an office building in the San Francisco Bay Area. The system was used to demonstrate the energy savings and demand-reduction capabilities of a lighting control system designed to exploit all major control strategies, including scheduling, daylighting, and lumen maintenance. After 9 months of operation, lighting energy savings of approximately 50% relative to previous usage have been consistently achieved. A novel, two-part control photocell that permits successful implementation of daylighting and lumen maintenance strategies was demonstrated