Think about how you feel when you walk into Best Buy, Home Depot or Target, compared to when you walk into Victoria’s Secret, Nordstrom or Crate & Barrel. Lighting plays a key role in creating the desired atmosphere.
Dramatic retail spaces use point sources, usually incandescent lamps with an integral reflector. They provide well-defined, high-contrast beams of light that can create focal points on merchandise, manikins, artwork and signage. The light should be between 10 and 40 times the surrounding brightness. High-end retailers keep the general light levels low and use point sources for visual cues.
Discount retailers use few or no incandescent lamps. Instead of high-contrast “pools” of light, they use bright uniform spaces to convey that they are discounters. Big-box stores, warehouse-style home centers, grocery stores and discount department store chains rely on fluorescent and metal halide lamps to create this effect.
New technology is now available to enhance quality and save energy costs.
• 24-Volt MR16 and MR11 lamps are miniature point sources that have been modified from the 12-Volt standard. The higher voltage means that more lamps can be placed on a transformer or longer runs can be achieved while maintaining even illumination. These are used in miniature track systems.
• MR8 (1-inch) lamps are miniaturized products.
• Halogen infrared technology offers reduced-wattage halogen infrared MR16s with equal or better life and lumens while saving 20 percent in operating cost, compared to standard halogen lamps. These halogen infrared parabolic aluminized reflector (PAR) lamps offer energy savings or extended life.
• AR111 lamps offer the most dramatic architectural source with beam distributions as tight as a 4 degrees distribution. This allows for very small, intense focal points or the ability to project light long distances with a bright, controlled beam.
• Lamp life of 100,000 hours is available. These lamps will operate 12 hours per day for 22 years. Applications include hard-to-maintain areas such as under high ceilings and over escalators. Downlights that use the QL lamps are also available. Both types have also been designed into decorative chandeliers, parking garage and street lighting products. These are often called electrodeless lamps because the electrode used to start the fluorescent arc stream has been removed to improve lamp life.
• T8 (1-inch diameter) lamps are now the best-selling fluorescent type. They offer up to a 40 percent system energy advantage over the old T12 (1½-inch) style. The magnetic T12 ballasts will not be available for commercial use after 2005. Premium 4-foot T8 lamps offer extended life (reduced maintenance) of 24,000 hours and a 30,000-hour lamp and ballast system has been introduced. Fluorescent ballasts are also changing with universal voltage, smaller-size housings and improvements in dimming capabilities.
• T5 (5/8-inch) lamps are being used in many of the new “indirect” linear fixtures designed for light to project on the ceiling and bounce through the space. Indirect fixtures are increasingly popular for retail use, offices and other commercial applications. These lamps offer about 12 percent energy savings over T8 and their small shape and high-lumen output allow for smaller-fixture designs. Such small lamps tend to glare, so they work well in the indirect design, where the lamps are not visible.
• Compact fluorescent lamps (CFLs) continue to become smaller and brighter. CFL lamps of 57, 70 and 80 watts are now available. Triple-tube CFL lamps feature “amalgam” technology to minimize the effect of temperature on light output. When operated in very cold or warm environments, light output is reduced dramatically with all linear and most other fluorescent products. The triple-tube lamps on the market now minimize temperature problems if you are using them in very cold or warm spaces.
Pulse-start metal halide has addressed the major concerns associated with the retailers that use high-intensity discharge (HID) lamps. This lamp-and-ballast system provides increased light output allowing for either fewer fixtures or reduced energy consumption. Standard metal halide lamps color shift dramatically but pulse-start products have improved color consistency. Pulse-start lamps hold their light output longer over life and in some applications offer up to 30,000-hour lamp life.
• Solid-state sources, such as LED products, continue to improve in lumen output and color rendering. All of the major lamp manufacturers have been jockeying for position in the architectural LED market in addition to the current automotive, exit sign and traffic signal applications. As these sources continue to mature and more luminaires are developed around them, they will have an increased effect on retailing and the lighting industry.
• Vertical cavity surface emitting lasers (VCSELs) are compact laser sources that excite phosphors with UV energy. The UV produced in fluorescent lamps excites the phosphor lining of the tubes and the phosphor glows. VCSELs are predicted to replace fluorescent tubes with the emitters having five to 10 times’ longer life, improved durability and smaller luminaire size.
The Optoelectronics Industry Development Association in Washington, D.C., predicts that LED/VCSEL technology by 2025 “should translate [globally] into cost savings of $100 billion a year.” Their white paper concludes that “No other major electricity application (motors, heating, refrigeration) represents such a large energy savings potential.” EC
LIEN is a senior market specialist at SOURCE/Cooper Lighting Training Center. He can be reached at firstname.lastname@example.org.