Sensor-Controlled Corridor Lighting in a High-Rise Residential Tower: Occupancy Patterns, Dimming Energy Savings, and Occupant Acceptance

In six corridors of a high-rise apartment building, light emitting diode (LED) luminaires were installed that dim to a low output when vacant (“bilevel”). Energy impacts were studied for three delay time settings. Occupant acceptance was compared to the conventional, fixed-output fluorescent lighting in use before the retrofit. Occupants had positive feedback and comments about the bilevel dimming of their corridor lighting. Luminaires programmed with the shortest sensor delay time (5 min) operated at high output for less time (22%) compared to those programmed with longer (15 min) delay times (31%). This resulted in 14% less energy use for the short delay time setting compared to the long delay time setting. Regardless of delay times, proximity to elevator lobbies increased the amount of time luminaires were at high output and therefore reduced energy savings. However, even in busy elevator lobbies, use of sensors to create bilevel control required about half as much energy as merely upgrading to fixed-output LEDs.