HB Series Cut Energy Usage in Half,
Improve Visibility for Naval Facilities
With operating costs continuing to soar, government facilities are always interested in ways to reduce their energy bills. When Naval Base Ventura County began to develop a plan to retrofit the lighting in several warehouses, hangars and a port gymnasium, the goal was to decrease energy costs as much as possible while enhancing visibility for individuals performing tasks within each facility.
The lighting retrofit was planned for 10 buildings at Port Hueneme, a large supply center and the only deep water port between San Diego and San Francisco, and Point Mugu Air Station near Oxnard, California. Nine of the buildings are warehouses ranging in size from 30,000 to 125,000 square feet. Two of the structures are 29,041 and 110,788 square-foot hangars, with a 24,743-square-foot gymnasium.
All of the structures were previously illuminated by mercury vapor, standard metal halide and high pressure sodium luminaires, with the most recent installation completed about 12 years ago. According to Tom Santoianni, LC, CEM, Energy Manager, Naval Base Ventura County, improving color rendition was essential to increasing visibility.
“Individuals working in hangar facilities must be able to identify the color of wires used in the electrical components of aircraft and missiles,” Santoianni said. “In the past, workers often had to take the components outdoors so they could correctly identify colors.”
Workers also need sufficient horizontal and vertical illumination so they can quickly and accurately identify products stored in warehouses—and especially in rack storage areas. So many dark areas and hot spots existed under the previous lighting systems that workers often had to take flashlights into rack areas to locate specific items.
Because Naval Base Ventura County is a government facility, the lighting project had to be put out for bid. Fixtures selected were Holophane HB Series high bay fluorescent luminaires with specular optical reflectors. Holophane performed a detailed lighting audit of the buildings included in the first phase of the retrofit and provided the Navy with recommendations and specifications.
During the selection process, Sempra Energy Ltd. was named general contractor for the project, which was administered through the Southern California Gas Company’s Energy Conservation Incentive Program. Amtech Lighting Services installed the HB Series luminaires and F32T8/850 lamps.
“We selected the Holophane high bay fluorescent luminaires because they are high quality and represent the best value,” Santoianni said. “The fixtures are available with a variety of beam spreads for optimal and efficient light distribution.”
Santoianni indicated he was interested in using luminaires with spectrally enhanced lamps because he had worked with the U.S. Department of Energy to field test spectrally enhanced lighting technology. Studies confirmed this lighting technique has the potential to save 20 percent more energy than commonly used T8/electronic ballasted fluorescent lighting systems and up to 50 percent more than T12 and magnetically ballasted lighting fixtures. Energy savings result from the naturally occurring visual efficiencies gained by lighting with a color spectrum that is more like daylight than most commonly used fluorescent lamps.
The F32T8/850 lamp used in the naval facilities has a color temperature of 5000K and a Color Rendering Index of 85. The lamp is often referred to as a Scotopic lamp because it produces light in the wavelengths of the color spectrum, which allows the human eye to see more acutely. A space will appear brighter with a Scotopic lamp than it will if it is illuminated by the common 4100K lamp with the same wattage and lumen output.
Luminaire spacing varies in the naval buildings, with luminaire placement determined by the mounting heights and illumination requirements. Mounting heights range from 11 to 24 feet above the finished floor in the warehouses and up to 32 feet in the hangars.
Individual sensors are used in about 90 percent of the high bay fixtures to shut the units off when an area is unoccupied or to take advantage of the natural light provided by skylights installed in some buildings. Photosensors are incorporated into luminaires installed near any of the large roll up doors that can be opened to allow daylight to come into the facility. All photosensors are programmed to override the occupancy sensors so the facility can use natural illumination whenever possible.
Light levels in all of the retrofit buildings meet Illuminating Engineering Society (IES) recommendations and range from 5 to 10 footcandles in warehouse storage areas and 50 footcandles in shop facilities. Light levels in the hangars are 10 to 75 footcandles, depending on the application.
HB Series high bay fluorescent fixtures with T8 lamps are also installed above the main floor in the gymnasium at Port Hueneme with light levels of 30 footcandles. Payback on the lighting system varies by building and ranges from four to 12 years.
“The HB Series fluorescent fixtures allowed us to meet specific application needs within each building while cutting energy usage by more than half,” Santoianni said. “The Holophane luminaires provide high quality, uniform illumination with sufficient vertical footcandles. Even though the fixtures cost more initially, their operational costs are lower over the long term than every competitive luminaire we considered.”