Below is an article about induction lighting I contributed to the July issue of TED Magazine. Reprinted with permission.
Induction lighting offers a longer-lasting alternative to HID and a potentially more cost-effective alternative to LED for high-intensity applications such as street, area, high-bay, industrial and sports lighting.
Induction lamps operate without electrodes, eliminating wiring connections between the lamp and its generator or driver. Most wear and tear on the system occurs at this point, so its absence significantly extends lamp life.
Currently, there are two types of electrodeless lighting. Plasma lighting, which will be the subject of this column next month, is essentially an electrodeless metal halide system. Induction lighting consists of a fluorescent lamp with electromagnets wrapped around a section of the tube. High-frequency energy emitted by an electronic ballast (generator) is guided into an electromagnetic field around the lamp, which excites the mercury atoms provided by an amalgam pellet and produces light. The phosphor coating on the bulb wall converts this light energy into visible light through the typical process of fluorescence. The light output exits the lamp from the surface of the bulb.
“Induction is fluorescent technology,” says Jodi Vallante, product manager, ICETRON Systems for OSRAM SYLVANIA. “However, it does not utilize a cathode or coil, which is the principal failure mode in a fluorescent lamp. This helps allow for very long operating life.”
The result is a solution that offers several significant advantages. First is longer life and associated maintenance benefits due to the absence of electrodes. Induction lamps are rated at 100,000 hours. Service life for typical fluorescent lamps is based on mortality, the point at which 50 percent of a large population of lamps will be expected to fail based on the operating cycle expressed in hours/start. Though the light source produces light through fluorescence, induction is rated similarly to LED and based on average lumen depreciation. For example, if the lamp is rated at 100,000 hours at L75, that is the point prior to which one-half of a sampling of induction lamps will be producing 75 percent of their original full light output. As with LED, it’s up to the owner to decide when the induction system should actually be replaced based on their light level needs.
Additionally, the system offers up to 65 percent lower energy consumption than HID, high color rendering, a range of color temperatures, higher lumen maintenance and virtually instant starting and restrike capability. Induction systems are available ranging from 35-400W and producing 2,450-36,000 lumens, with a CRI of 80+ and 2200K-6500K color temperatures.
The lamps are available in circular, linear and bulb shapes of various sizes to satisfy different application needs, with some circular and bulb-shaped lamps available with a mogul or medium screw-in base. Cold-start and remote-mounting options are also available. The solution may be purchased as a system for retrofit of existing luminaires or as complete luminaires ready for installation. More utilities now recognize induction lighting in their commercial lighting incentive programs. According to Briteswitch, LLC, the average rebate for an induction high-bay luminaire ranges widely but is currently $84.50.
Image courtesy of 1st Source Lighting.
Induction lighting is typically controlled in exterior applications with photocells for dusk-to-dawn operation. However, some systems can be dimmed using step dimming or 0-10V continuous dimming from 100-40 percent of lamp power, allowing induction systems to be specified in projects complying with commercial building energy codes requiring bilevel control. Add-on components can be used to achieve wireless lighting control. When dimmed, induction lamps do not have the same color shift issues as HID and plasma lamps.
“Induction is always an attractive option relative to HID, even in the medium term for new construction, given both its swift payback from energy savings and the maintenance savings available from its 100,000-hour long life,” says Jay Matsueda, director of marketing for Fulham Co., Inc. “For existing buildings, induction is relatively easy to use for retrofitting as well, thus preserving one’s investment in existing fixtures and increasing induction’s demand.”
Induction competes with HID and also with LED, which presents another long-lasting alternative. Ironically, it appears that the proliferation of LED technology may have spurred growth in demand for induction lighting as a lower-cost alternative.
“Induction saw a surge in demand in the past three years mainly in retrofit applications and especially in street and area,” says Vallante. “LED systems gave induction a surge as induction price points tend to be lower than their LED equivalents. Induction will continue to have its place in the lighting market where customers desire high-quality fluorescent performance over a very long operating cycle. The opportunities going forward with induction will mainly be in the high-wattage, high-lumen packages and 100W dimming.”
“While LED has gained a recent foothold in down, track, sign and display lighting applications,” says Matsueda, “LED lighting remains relatively expensive compared with induction, translating into a longer payback period. Additionally, current LED technology does not yet perform well in applications with high ambient temperatures.”
Vallante adds: “Induction will always be the long-life, white light leader or alternative. Customers always like choices, and induction has proven installations of over 10 years without having to do a chip or driver change.”
Image courtesy of 1st Source Lighting.
She and Matsueda caution that thermal measurements should be taken when retrofitting existing luminaires to induction. “Heat is the enemy of any lighting system, and retrofit systems sold as kits through authorized distributors have been tested to perform under specific conditions,” Matsueda says. “One simply cannot install induction without proper thermal testing, just as one cannot responsibly use any other type of technology without doing so either.”
The final word: “Electrical distributors can count on induction lighting because it is a proven, reliable operation that delivers high-quality, long-life light where and when needed,” Vallante says. “For electrical contractors, this means satisfied customers.”
You must be logged in to post a comment.