Smart Corridor Bi-Level Lighting for Office Applications

The objective of the Smart Corridor project is to quantify the potential energy savings in corridor lighting by implementing bi-level lighting technologies in commercial spaces such as office, hospitality, and educational buildings while also evaluating the market potential for the bi-level lighting strategy. The energy savings data gathered from this project is crucial to the large-scale implementation of bi-level strategies, as it will support the inclusion of bilevel lighting practices for secondary spaces in utility incentive programs and, eventually, building code language. Bi-level lighting strategies for secondary spaces, such as corridors and stairwells, reduce light levels and power consumption during periods of vacancy. Two commercialized bi-level lighting systems are evaluated in this study. The Lutron Electronics, Inc. system was installed at the Landmark Square office building in Long Beach, California. This site represents ‘Class A’ office buildings. The Redwood Systems solution was installed in the Natural Sciences 1 building at the University of California, Irvine. This site represents educational office buildings. These sites have low occupancy rates in secondary spaces, making them ideally suited for bi-level lighting strategies. Based on today’s commercialized product offerings, the typical installation of bi-level lighting strategies is calculated to save 25-49% energy use. There is potential for even higher savings in areas with lower occupancy rates. To vet this estimation, field installations were conducted in Southern California Edison (SCE) service territory to demonstrate commercially available advanced control systems in retrofit applications. Data gathered by ADM Associates, Inc. demonstrates that the bi-level systems installed in office and educational building retrofit settings saved 46-65% annual energy use (kilowatts per hour (kWh)) per fixture. Survey results show 25% of the total commercial lighting energy use in the education sector is attributed to corridors.1 By reducing lighting energy consumption in secondary spaces through bi-level lighting strategies, commercial buildings are estimated to reduce their lighting energy use by 12-16%. In contrast to the demonstrated energy savings summarized in Table 1, long payback periods shown in the demonstrations implemented for this study confirm that the combination of material, installation, and commissioning costs for these systems must come down in price for these systems to be within an acceptable payback range for the typical end user. Calculated paybacks for installed systems range from 25 to 220 years, varying based on occupancy rate and installed fixture wattage compared to pre-existing fixture and control mode (i.e., on/off switches, time clock, etc.).