With 108,887 passengers arriving on 1,486 airplanes during a typical day at Phoenix's Sky Harbor International Airport, engineers that maintain the airport facilities are always concerned that its various lighting systems provide a safe, pleasant environment 24 hours a day, while saving energy whenever possible.

To maintain the lighting installed in millions of square feet of buildings spread over the 285-acre airport, the engineers carefully follow lamp and ballast manufacturers' recommendations for duty cycles, and schedule off times for as much of the lighting as possible to maximize component life. They rely on Watt Stopper/Legrand lighting controls to manage these parameters and to harvest the energy savings of daylighting whenever possible. The Skybridges retail area (shown above) and other parts of the airport with large windows, as well as perimeter areas of the parking structures rely at least in part on natural lighting whenever possible.

To do this, the airport's scheduled control is made possible by more than 140 lighting control panels installed over 17 years throughout the complex. Many of the panels were retrofitted onto existing electrical circuits. Networked control makes the scattered panels accessible from either of two central locations.

The Aviation Department's user technology specialist responsible for the system has developed a control schedule for each area that periodically cycles the lighting off during a time that will least impact operations to extend lamp and ballast life. He also relies on status reports from Watt Stopper/Legrand's WinControl software to alert him of possible failures within the lighting systems. He can then dispatch a technician to check out a specific relay in a specific location if a failure is reported, saving hours of manpower that might otherwise be needed to locate the problem. More information on this installation is available at www.wattstopper.com.