Study Shows Value of Sensor-controlled, Bi-Level Lighting

February 8, 2019

Considerable energy savings can be achieved with sensor-controlled, bi-level corridor lighting, according to results of a field demonstration led by the Lighting Research Center (LRC) at Rensselaer Polytechnic Institute.

The field demonstration looked at sensor-controlled, bi-level corridor lighting in a multi-family apartment building. 

“Saving lighting energy in multi-family corridors is becoming more feasible,” says Jennifer Brons, who authored a report on the field demonstration. “LED luminaires can easily dim light output when corridors are vacant, rather than turning off entirely. Most importantly, the occupants had positive comments about safety and comfort with sensor-controlled, bi-level lighting.”

Dimming light output when corridors are vacant, rather than turning off entirely, is referred to as “bi-level” or “adaptive” lighting. Sensors can be mounted in each luminaire, or can be wirelessly linked to multiple luminaires. 

Project background

With support from the New York State Energy Research and Development Authority, the LRC and Taitem Engineering collaborated with Albany Housing Authority to upgrade 60 corridor lights on six floors of a below-market-rate apartment building in Albany, New York, known as Lincoln Square Two. Monitoring results from 14 other apartment buildings enabled energy savings calculations comparing market rate vs. below market rate buildings.

Lincoln Square Two is part of a complex of high-rise apartments built in the 1960s. The project involved upgrading 60 corridor lights (6 floors, 10 per floor). 

Previous lighting consisted of linear T8 fluorescent lamps4 in surface-mounted luminaires spaced typically 13 feet
(4 m) apart. Although lamps were in good working order, plastic cube louvers had yellowed with age, thus distorting colours and reducing luminaire light output. Before the retrofit, average illuminance on the floor was 106 lux (10 fc). 

For this research, each of the previous fluorescent luminaires were replaced one-for-one with LED luminaires controlled by integrated ultrasonic occupancy sensors. Luminaires were rotated to orient parallel to the corridor to improve light distribution on the walls. Each of the new luminaires was set to operate at 100% output when occupied (average 303 lux at floor level); when vacant, luminaires dimmed independently to 20% of full output. Twenty of the new luminaires were set for each of the three delay time settings: 5, 10, or 15 minutes.

Resident feedback

The LRC administered a questionnaire to compare occupant acceptance to the conventional, fixed-output fluorescent lighting in use before the retrofit. Despite the higher light levels with the new lighting, most occupants did not consider the hallways too bright after retrofit. Over three-quarters (78%) of the occupants approve of the new bi-level lighting. More of the occupants had positive ratings after retrofit than before retrofit.

The occupants also offered positive comments about the retrofit. Multiple people commented that they like how the individually controlled luminaires ramp up light output successively as they walk through the corridor. One person likes that the sensors act as a notification that others are present. Several people simply prefer having more light in the corridors, independent of sensor features. There were no negative comments about the sensors. 

Estimated annual energy use 

Energy impacts were studied for the three delay time settings. Luminaires programmed with the shortest sensor delay time (5 minutes) operated at high output for less time (22%) compared to those programmed with longer (15 minute) delay times (31%). This resulted in 14% less annual energy use for the short delay time setting compared to the long delay time setting. 

Proximity to elevator lobbies increased the amount of time luminaires were at high output, and therefore reduced energy savings in these areas. However, even in busy elevator lobbies, bi-level lighting used about half as much energy as only upgrading to fixed-output LEDs. 

The LRC calculated annual energy use for 48 luminaires comparing the previous T8 fluorescent luminaires to two conditions: LED luminaires without sensors, and bi-level lighting programmed with a 5-minute time delay. At this high-rise residential site, use of sensors to create bi-level lighting more than doubled energy savings compared to upgrading to fixed-output LEDs.

Key findings

The Lincoln Square bi-level lighting demonstration showed that

  • over three-quarters (78%) of the occupants approved of the new bi-level lighting
  • 5-minute delay time was not objectionable
  • dimming to 20% light output when vacant was not objectionable
  • use of sensors to create bi-level lighting more than doubled energy savings compared to upgrading to fixed-output LEDs
  • the lower the dim setting when vacant, the greater the energy savings due to bi-level lighting

Read the full study here.

Related Articles


Changing Scene

  • LEDVANCE Expands Ontario Presence with New Specification Agent

    LEDVANCE Expands Ontario Presence with New Specification Agent

    LEDVANCE is pleased to announce the appointment of Sterling Architectural Products Ltd. (Sterling Lights) as their new specification agent in Ontario. This partnership strengthens LEDVANCE’s presence in the region and reinforces their commitment to serving the professional lighting design and specification community with innovative, reliable lighting solutions. With decades of experience and a service-driven mindset,… Read More…

  • May 29, 2025 - Eureka Wins Three 2025 Red Dot Awards for Product Design

    Eureka Wins Three 2025 Red Dot Awards for Product Design

    Eureka is pleased to announce that its Velia, Cirra, and Junction luminaires have each received a 2025 Red Dot Design Award for Product Design. It is the 11th consecutive year that Eureka products have been honored with this prestigious award, which is a testament to the company’s consistency and relentless drive to design exceptional luminaires.… Read More…


Design

  • The Difference Between Accent, Ambient & Task Lighting: Ultimate Guide

    The Difference Between Accent, Ambient & Task Lighting: Ultimate Guide

    In interior design, lighting is not just about brightening the room. Sensitive lighting layout is the key in the whole aesthetic atmosphere. An outstanding lighting solution will not rely on one type of fixture. Rather, it is through the combination of different types of lighting. Accent, ambient, and task lighting are three basic types of… Read More…

  • Graphic Office Interiors Enhance Their Office Space, Incorporating State-Of-The-Art Lighting Solutions

    Graphic Office Interiors Enhance Their Office Space, Incorporating State-Of-The-Art Lighting Solutions

    Graphic Office Interiors, a renowned office design and furnishings company serving Vancouver Island since 1966, embarked on a unique lighting project for their personal office in Saanichton, BC. This project marked the first collaboration between Kelly Inglis of Mac’s II Agencies and Graphic Office Interiors’ in-house registered interior designer, Laura Harlos. Known for their exclusive Steelcase furniture line, modular moveable… Read More…


New Products

  • SATCO|NUVO: LED T8 With Integrated Emergency Backup

    SATCO|NUVO: LED T8 With Integrated Emergency Backup

    SATCO|NUVO’s LED T8 Lamps with Emergency Battery Backup are UL924 listed for use in emergency lighting applications. Custom lamp holders and set screws lock the lamp in place for a secure installation, and lamps feature red endcaps so they can be easily identified when inspected and maintained. The test button allows for easy testing of… Read More…

  • Eureka Announces New Accessories for Scout Luminaire

    Eureka Announces New Accessories for Scout Luminaire

    Eureka has announced the enhancement of its Scout luminaire family with the introduction of new accessories and a new color palette. Three new diffusers have been introduced. Bell is minimalist, translucent and cloche-shaped. Pebble introduces a soft touch and an ambient glow in a distinct, oval-shaped diffuser. Orb is sleek and dome-shaped, adding a touch… Read More…