Lighting controls increase energy performance
Engineers should look at the specific lighting control requirements in the latest versions of ASHRAE Standard 90.1 and IECC and review some best practices and insights on how incorporating lighting controls influences a building’s energy performance.
Daylight zone control
The use of natural daylighting compares favorably to most artificial lighting systems, and the codes are written to take advantage of daylight as a supplemental lighting source. In spaces with plenty of daylight, this strategy is inherently one of the best ways to reduce lighting energy consumption by controlling the amount of time the fixtures are on during occupied hours. The energy codes define various “daylight zones” based on side- or top-lighted areas and require that these zones are separately controlled.
Specialty and parking garage controls
The code also mandates that additional controls are required to automatically reduce lighting levels of fixtures located with 20 ft of a perimeter opening exposed to daylight. Similar to the indoor application of daylight control, garage daylight sensors must be installed to reduce the light output in response to daylight.
Total building lighting control solution
lighting control system is a digital architecture that integrates occupancy-, schedule-, and daylight-based controls into one networked system (see Figure 2). The network control system includes addressable light fixtures, switches, occupancy/vacancy sensors, relay panels/time switches, and photosensors, and when implemented in a facility, it not only meets the current energy code requirements, it also reduces energy consumption and enhances occupant convenience. The system provides the ability to modify any number of parameters such as adjusting time delays in specific occupancy sensors, recalibrating setpoints for daylight controls, and adjusting maximum power consumption on any device in the network from a single location. As the system is calibrated to more accurately react to occupant schedules and the presence of natural light, the overall building lighting power consumption may reduce significantly.
Danna Jensen has 14 years of experience at ccrd in Dallas, where she became associate principal in 2012. Most of her work consists of designing electrical distribution for hospitals. She also designs electrical systems for office and retail facilities. She is the project manager for major hospital projects, which includes knowledge of all mechanical, electrical, plumbing (MEP), and fire protection systems, as well as commissioning. Jensen was a 2009 Consulting-Specifying Engineer 40 Under 40 winner and is a member of the Consulting-Specifying Engineer editorial advisory board. Jason Jullie has 10 years of experience with ccrd in Dallas as an electrical engineer and associate. He works mainly in the health care field designing electrical distribution systems. He is a 2014 Consulting-Specifying Engineer 40 Under 40 winner.