New daylighting retrofits for Army facilities in Hawaii include skylights in a hangar at Wheeler Army Airfield. Photo by Scott Bly, NREL PIX 07625. USAG-HI accepted the unsolicited proposal from Hawaiian Electric after completing two previous daylighting test projects. The fixtures replace conventional electric lighting during the day, bringing daylight into the building via an enhanced skylight system. When direct and ambient sunlight strikes an impact-resistant acrylic dome, it is directed through a reflective light shaft and transmitted onto an interior diffusing lens that spreads the light evenly below.
Automatic controls turn off the electric lights in the building as daylight levels rise.
Warehouse lighting illumination levels are designed to be about 10 foot-candles. Daylighting increases that level by approximately 500 percent during most of the day. It also improves building occupants' productivity and morale, and reduces building maintenance costs. The skylights are estimated to reduce total lighting costs by 85 percent, and have a simple payback period of about 10 years. Daylighting fixtures are now in place in warehouses at East Range, a gym at Schofield Barracks, and an aircraft hangar at Wheeler Army Airfield, Hawaii.