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More than $640 million could be saved annually nationwide if only a small percentage of businesses updated their lighting to more energy-efficient systems. According to a recent study by Venture Lighting International and the American Council for an Energy Efficient Economy, lighting accounts for approximately 40 percent of commercial electric bills.
High-intensity discharge (HID) lighting, featuring metal halide (MH) and high-pressure sodium technology, is commonly used in commercial, industrial, retail and municipal applications. According to Wayne Hellman, chairman and CEO of Advanced Lighting Technologies Inc., new technology MH lighting has provided high-intensity white light offering longer life, improved color uniformity and significant energy savings.
“New formed body arc tube lamps give improved lamp-to-lamp color consistency, higher lamp efficiency and faster warm-up,” Hellman said. “The lamps also give a faster hot restrike––typically 60 percent faster than a traditional metal halide lamp.” Arc tube geometry is a major factor in controlling a lamp’s thermal characteristics. A formed body tube allows the lamp designer to optimize the thermal profile of the arc tube to achieve the desired lamp performance characteristics.
“Geometric inconsistencies are reduced even more in the recently introduced 300W and 320W pulse-start lamps because of the shaped arc tube’s tipless design,” Hellman said. “The manufacturing process that injects the halides and gases through the arc tube’s end eliminates the need for an exhaust tube. The halides distribute evenly along the arc tube wall, resulting in further color quality improvement.”
Arc tube design performance characteristics often are misconstrued, especially the heating patterns of cylindrical and formed body arc tubes. “One myth says because the shaped design is hotter on the ends, this causes poor lamp performance and shorter lamp life,” Hellman said. “Formed arc tubes are designed to be hotter in the end regions, resulting in more heating of the halide salts in the ends.”
MH lamp designers create arc tubes that heat halides to the highest possible temperature without exceeding the thermal limits of arc tube materials. These shaped arc tubes optimize lamp performance by controlling temperature, which, in turn, increases efficiency and improves color uniformity. The result is a high quality and quantity of light from the pulse-start lamp.
HID lighting sources have improved significantly. Increased energy-efficient models have succeeded lighting systems once thought to be energy efficient. Unfortunately, businesses have not moved as quickly as technology. Currently, more than 40 million 400W metal halide and 10 million high-pressure sodium energy-wasting fixtures are being used.
In an attempt to lower initial start-up costs, manufacturers such as Venture Lighting International, a subsidiary of Advanced Lighting Technologies Inc., have created retrofit solutions to allow companies to change out of their old technology lamps and ballasts without changing their current fixtures. The return on investment of switching to newer energy-saving technology could pay off in less than two years with substantial savings in years to come.
Venture Lighting calculates that retrofitting a new 300W MH system to replace the common 400W MH technology will save up to 135 system watts, while producing the same light––with faster warm-up, faster re-strike, longer life and superior color uniformity.
• The 300W lamp saves approximately 810 kWh of electricity per year (based on 6,000 kWh annual usage).
• At 10 cents per kWh, the savings equals $81 per year per fixture.
In a typical warehouse, big-box retailer or assembly operation with an average of 400 fixtures, energy savings could be $32,000 per year.
Venture Lighting’s tipless process injects the halides and gases through the end of arc tubes, thus eliminating the exhaust tube tip. “This distributes halides evenly along the arc tube wall, resulting in color uniformity equal to ceramic metal halide lamps,” said Donna Bard, product manager, Venture Lighting International. Currently available in 300W and 320W lamps, the tipless process will be in 175W through 450W by the end of this year.
Ron Newbold, light fixture manager, Progress Lighting, said the Genura lamp is like the incandescent BR30, but has a much longer life. It is a medium-base, electronic self-ballasted lamp that lasts 15,000 hours. The 23W lamp gives same output as 65W BR30, the standard lamp used in residential recessed lighting.
More emphasis is placed on color-enhanced bulbs. GE’s Reveal bulbs filter out yellow rays to produce a crisper light, which reportedly enhances the richness of walls, artwork, fabrics and clothing in homes. Mary Beth Gotti, manager of GE’s Lighting Institute, said different shapes of halogen bulbs, particularly reflectorized types including parabolic aluminized reflector (PAR) bulbs, make them popular for downlights and tracklights. EC
WOODS is a freelance writer based in the Phoenix area. She can be reached at [email protected].