High Bay OptionsSeveral new choices are now available for industrial and other high-bay environments (e.g., gymnasiums, exhibition halls) where high intensity discharge (HID) lamps are in heavy use.
Some new high-bay fixtures instead use several (up to eight) large, compact fluorescent lamps (CFL) in each fixture, surrounded by a computer-designed reflector to concentrate their output. A single fixture using multiple 42-W CFLs provides the same output as a single 250-W metal halide fixture using the same total wattage. It does so, however, without the long startup/restart period, major lumen depreciation over time, color shift, or safety hazard inherent in many HID lamps.
For products from one of the early developers of this option, check out www.sportlite.com.
While high-pressure sodium (HPS) was long considered the front runner in the lighting efficiency department due to its high lumens/watt rating, recent findings show that higher quality (i.e., color rendering index, or CRI) light may achieve the same visibility at lower foot-candle levels.
To painlessly make the switch from HPS to metal halide (MH), which has a much higher CRI, Venture Lighting now offers its White Lux MH lamps, which run on HPS ballasts. In some applications, one may shift to a MH lamp with a wattage lower than that of the existing HPS lamp while providing the same (or better) visibility. For details, go to www.venturelighting.com.
Older HID fixtures can be converted to the new pulse-start HID lamp technology by changing out just their lamps and ballasts. This system provides the same (or better) light output with a 15% to 25% wattage reduction, faster startup/restart, and better lumen maintenance than standard HID. Find a quick explanation of this technology at http://www.advancetransformer.com/literature/pdf/HI-4060-R01.pdf.
Fluorescent Dimming For Fun And ProfitIn public areas (e.g., hallways) containing many watts of fluorescent lighting, replacing standard electronic ballasts with dimming ballasts may now make economic sense. Where power costs are high (the Northeast and parts of the western United States), reducing load during certain times of the day (or when one's power supplier asks) may offer major financial returns.
In most public spaces, few people will notice temporary reductions in normal light levels (up to 35%), especially when done gradually (e.g., over a 3-min period). Low-cost dimming ballasts (i.e., less than $100) and power line control (PLC) systems are available that provide this option. Dimming may also be cost effective in other spaces when full light levels are not needed, such as cleaning, restocking, security, etc. Check out one vendor's PLC dimming ballast, at http://www.advancetransformer.com/literature/pdf/EL-2020-R01.pdf.
Accent Lighting With HIDWhile CFLs have replaced many incandescent lamps, spot and accent lighting have resisted that change. Focused light may be needed to produce sparkle and high contrast (such as on artwork and jewelry) but CFL output is hard to concentrate due to the emission of its light from a surface instead of a small filament.
For several years, electronically-ballasted mini-MH lamps (such as the Philips MasterColor series, and similar units from Osram and Philips) have been available for track and spotlighting. It is now common to find them in new retail outlets in areas with high electric rates. For details on the MasterColor HID lamps, go to: http://www.lighting.philips.com/nam/prodinfo/hid/mastercolor/p5433a.shtml.
Test Before You InvestBefore buying into any new technology, set up an isolated test location for it. If the new system fails, the problem can be addressed without the usual distress that occurs in someone's workspace.
New lighting systems continue to appear every year. If you manage or consult to large facilities, it is worth your time to annually refresh your knowledge in this area. The dual impacts of high-tech controls and low-cost chips continue to raise the bar for energy-efficient lighting. ES