Residential Lighting Energy Use Reduction Study

This project studied the potential of vacancy sensors to reduce residential lighting energy use. Vacancy sensors turn off lights when spaces are unoccupied for anywhere from five to 30 minutes, depending on the programmed setting.

A key distinction between vacancy sensors and occupancy sensors is that with vacancy sensors the lights are manually turned on and will not coming on automatically when the room is entered. The study monitored lighting use in designated rooms within 30 townhouses and flats for one year.

During the first six months, utilization monitors tracked when the lights were on and when the rooms were occupied or not. This established the baseline of lighting use. After six months, vacancy sensors were installed in the monitored rooms. Following the 12 month monitoring period, data analysis will show the difference in lighting use before and after the installation of the vacancy sensors.  

This research was intended to serve as a basis for a potential vacancy sensor utility incentive program.  Final analysis and project results are in process, but preliminary results show that savings can be significant.