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As the price of energy climbs and the specter of deregulated energy looms large, property managers around the country are considering the benefits of retrofitting their facilities with energy-efficient indoor and outdoor lighting. Energy costs account for about 86% of the life cycle of lighting. Opportunities for quick and long-term payback abound for both indoor and outdoor lighting. One widely recommended quick fix is the replacement of incandescent lamps with compact fluorescent lamps which screw into the same socket. Another retrofit with short payback is the replacement of linear fluorescent T12s with T8s. Metal halide is an economical option for outdoor commercial installations. Timers and occupancy sensors can achieve savings indoors and outdoors.

As the price of energy climbs and the specter of deregulated energy looms large in many states today, property managers around the country are considering the benefits of retrofitting their facilities with energy-efficient indoor and outdoor lighting. Given the new technologies available for commercial and industrial lighting, an installation that might have seemed perfect five years ago could be wasting a lot of energy today.

While the national media has focused on California's ongoing energy problems these past several months, higher energy prices are a reality for many areas of the country. Every facility that has not yet optimized energy conservation in lighting installations can benefit from a retrofit with energy-efficient lighting products (lamps, fixtures, and controls) or using those elements in new construction. Indeed, energy costs account for about 86 percent of the life cycle cost of lighting. The balance is a result of future maintenance and the purchase of the fixture. Opportunities for quick and long-term payback abound for both indoor and outdoor lighting.

To help identify these opportunities, some manufacturers of lighting products offer free facility energy audits pinpointing areas where energy expenditures can be reduced or provide free software and comparison charts that demonstrate product value over time.

One widely recommended quick fix is the replacement of incandescent lamps with compact fluorescent lamps (CFLs), which screw into the same socket. CFLs typically offer the same amount of light for about 75 percent less energy. Likely locations for this speedy retrofit include lobbies, reception areas, private offices, and restrooms.

Another relatively easy retrofit with short payback is the replacement of linear fluorescent T12s, the long-time workhorse of commercial and industrial facilities, with TBs, which offer more lumens per watt and a longer rated life. A 32-watt T8 (which is 8/8ths in diameter) yields 92 lumens per watt, while a 40-watt T12 (12/8s in diameter) yields between 45 and 74 lumens per watt.

"When paired with electronic ballasts, which are more efficient than magnetic ballasts, T8s can save about 43 percent in energy costs right off the bat, for that part of the installation," points out Steve Goldmacher, Director of Public Affairs, Philips Lighting Company, North America.

Whether as a total retrofit solution or for new construction where fluorescent lighting is the lighting of choice, it is worth considering to downsize further to the newer linear fluorescent T5 lamps, which require special T5 fixtures. Just 5/8 of an inch in diameter, T5 lamps fit into fixtures that are 40 percent smaller than T8 fixtures and 60 percent smaller than T12 fixtures. The lamps are available in two versions, the standard TS (high efficiency) and the TS HO (high output), which yields up to 70 percent higher light output than the standard T5. Manufacturers typically offer the lamps in a range of lengths and wattages. Philips Lighting's Silhouette TSs, for example, are available in 22-, 34-, 46- and 58-inch nominal lengths and at 14, 21, 28 and 35 watts for the standard T5 and at 24, 39, and 54 watts for the T5 HO.

The size of the T5 lamp has afforded future manufacturers more leeway in creating smaller fixtures that, using baffles, louvers, or cutouts, can shield varying amounts of light, reducing glare while improving the quality of light. Because the lighting is more effective, TS lamps can be used at lower levels. And because the fixtures are smaller than TBs, they can be used as sources of indirect lighting in areas where ceilings are relatively low. TSs are viable choices not only for surface- or pendant-mounted row lighting across a ceiling but also for cove or perimeter lighting and task lighting.

Goldmacher also suggests using some types of metal halide lamps as another energy-saving option for general (ambient) lighting in new construction of commercial and industrial facilities. Philips MasterColor Metal Halide Lamps, for example, offer a high degree of efficacy (lumens-or amount of light achieved-per watt) and excellent color stability over the life of the lamp.

For areas with white or off-white ceilings that reflect light well, lighting designers are often able to use metal halide lamps for indirect ambient lighting along with floor or desk fixtures fitted with CFLs for supplemental task lighting at the local level. The overall effect can be pleasing, aesthetically. "Combining lighting sources can be a great energy saving option that takes away that cold office look," notes Goldmacher.

Outdoor Lighting Savings

Metal halide is also an economical option for outdoor commercial installations, such as parking facilities, where good coloring rendering is desired after dark. Metal halide provides good visual performance at lower light levels than high-pressure sodium (yellow) lamps. Pulse start metal halide, incorporating special pulse start ballasts, yield more light per watt than standard metal halide, further reducing energy expenditures and extending lamp life.

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Fixture manufacturers have developed a variety of solutions for outdoor lighting featuring better optics that take advantage of the new energ-efficient lamps. Luminaires that distribute light in a more efficient fashion, in turn, can utilize a lower wattage bulb, with no compromise in amount of light.

The style and positioning of outdoor fixtures contribute to energy savings. Full cut-off fixtures, which can mount horizontally or vertically, concentrate all lighting down, rather than wasting any energy lighting up the sky. Vertically mounted lamps yield 10 percent more light than horizontally mounted lamps, provide more uniform light, and last up to 66 percent longer.

GE Lighting's new Criterion series of integrated modular lighting wall- and pole-mountable fixtures, available for horizontal and vertical mounting and accepting high pressure sodium, metal halide and pulse start metal halide lamps, is an example of how well-designed outdoor fixtures can help achieve energy savings across a facility installation. All fixtures are available with improved photometry which, notes Tony Burns, Manager-Marketing Programs, GE Lighting Systems, allows properties to use less wattage for the same effective light as well as fewer fixtures across an installation. This leads to fewer poles and lower installation costs as well as long-term energy savings.

Criterion features plug-in replaceable parts and upgradeable components that snap onto or off of a universal footprint platform. The series incorporates several technologies that can help minimize power consumption throughout an installation, including the ability to add a snap-on module that offers bi-level 400 watt/250 watt lighting from the same 400 watt horizontal, vertical or flood luminaire. This energy-saving feature is currently available for HPS lamps and, notes the company, will soon be available for metal halide lighting as well.

By incorporating a programmable timer, you can set up an outdoor lighting installation that will automatically run the 400-watt lamps during active evening hours and run the 250-watt lamps at other times. During the lower wattage hours, you could incorporate an occupancy sensor, to activate the higher wattage lamps as soon as motion is detected, providing energy efficient security lighting when needed, points out Burns.

Lighting Control

Timers and occupancy sensors can achieve savings indoors and outdoors, 24/7. Programmable scheduled controls, for example, are costeffective solutions for saving on lighting in various public areas where there is not likely to be usage at particular times. Occupancy-based controls, which switch lights on in response to perceived movement in an area, "should be prime considerations in common areas where there is no ownership, such as lobbies, hallways, stairwells, and restrooms" notes Jerry Mix, President of The Watt Stopper. They are also well suited to storage areas, copy rooms, and offices. "There are, in fact, higher savings possible in the more frequently used areas, such as individual offices, where people don't think to turn lights off when they walk out, " he adds.

There are three types of occupancy sensors-passive infrared (PIR), ultrasonic, and dual technology, which combine both types. PIRs react to movement of a heat source in direct line of sight and work best in small offices and other enclosed spaces.

Ultrasonic sensors rely on (inaudible) changes in sound frequency and can detect very minor motion. They are well suited to spaces with infrequent occupancy, such as restrooms or warehouses, and would also work well as part of a bilevel lighting strategy for hallways and stairwells. You can use fluorescents or compact fluorescents at a lower lighting level when the space is unoccupied and at another level when an occupancy sensor detects activity.

All three types generally feature time-delay shut-off and can be used with dimming controls to lower the light level in areas such as conference rooms, where you may want to maintain lights at a low level rather than off, for safety or security.

Manual and automatic dimmers and other light level controls adjust the light output either according to user need at the moment or in accordance with a pre-determined schedule that can take into consideration daylight harvesting in areas with access to natural light. You might want to give employees in perimeter offices control of their own ambient and desk-top lighting loads, suggests Mix.

Centralized controls that activate or deactivate, dim or brighten various loads throughout a facility under pre-specified conditions are also available. Featuring local override capability and the ability to work with stand-alone controls such as occupancy sensors and dimmers, they offer a great deal of flexibility for retail stores, manufacturing facilities, and convention centers. For example, centralized controls may be set to accommodate various presumed and actual levels of activity throughout a 24-hour cycle.

To help end users sort out the choices and understand the potential savings, several lighting controls manufacturers offer onsite energy audits that help identify areas where specific types of controls would be effective. Some companies, including The Watt Stopper, use occupancy loggers to indicate areas where appreciable amounts of energy are lost lighting empty space. The Watt Stopper also utilizes a desktop plug load analyzer to incorporate data on desktop plug loads. One very easy way to capture energy savings throughout a facility, notes Mix, is to supply each desk-bound worker with a plug load control operable at the local level. For optimized savings, the company's Isole Power Strip also incorporates an infrared motion sensor that turns the loads on and off based on the presence of people inside the cubicle.