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Indulging the Control Freaks

April 1, 2003
Being able to control the lighting in your office may not seem like a big deal to you. But in a time when good people are hard to come by and hard to

Being able to control the lighting in your office may not seem like a big deal to you. But in a time when good people are hard to come by and hard to keep around, a little employee satisfaction can make a big competitive difference. Often what employees need is not so much more money or more recognition but a stronger sense of control over their surroundings.

Recent research in lighting controls suggests that workers who have the power to control their lighting will tailor it to their surroundings and their activities. This can enhance productivity while saving on electricity bills. By learning about the benefits of lighting controls and some of the latest thinking in their use, distributors can put themselves in a position to help customers develop a competitive edge in productivity and employee satisfaction. Not that many really good employees are going to stick around just to play with the dimmer, but any little bit can help. Anyway, the tight labor market is just one of several factors at work in the market today that suggest distributors and their customers could get more out of lighting controls.

Overall, these are good times in the office lighting market. The U.S. economy's construction boom of the past few years has been strong enough to resuscitate commercial office construction, a market sector that had tanked in the 1980s and early '90s because of overbuilding by speculators. As companies expand and new firms start up, the demand for new office space employing the latest technology in energy efficiency, communications and convenience is now driving new office construction in metropolitan markets throughout the country.

Beyond the new-construction trend, the boom of interest in energy-efficient retrofits has been the biggest story in office lighting. Energy crusaders may be disappointed about the pace of retrofits, but a lot of these projects are being done.

Energy conservation is perhaps the most powerful factor driving current demand for lighting controls. Lighting controls play an expanding role in the energy conservation market, primarily because they pick up where other lighting technologies leave off (or leave on, as the case may be). Energy-efficient lamps and ballasts can do a lot to cut energy costs, but lighting controls such as dimmers, timers, occupancy sensors and photosensors that dim or turn off the lights when a space is not being used can make a lot of difference. Occupancy sensors alone can account for energy cost savings of 40%. Lighting controls have a central role to play in maximizing the energy efficiency of offices, but their impact goes far beyond lower utility bills.

The contributions T-8 fluorescent tubes, electronic ballasts, specular reflectors and the like can make in energy savings are well documented. Fewer and further between, though, have been studies that document how lighting controls affect the energy consumption of a building and how people use these controls.

Last summer, researchers from the Lighting Research Center (LRC) at Rensselaer Polytechnic Institute, Troy, N.Y., reported on a study they had done of lighting controls in an office building. The intent of the study was to put some numbers on the intangible aspects of office lighting control, says Dorene Maniccia, LRC's manager of Lighting Applications, who led the research team.

The LRC researchers spent about four months at the offices of the National Center for Atmospheric Research (NCAR) in Boulder, Colo., watching how often and under what circumstances workers adjusted their blinds, turned their lights on and off, or dimmed their office lighting. The 58 offices studied, each of them lit by two three-tube fluorescent troffers equipped with T-8 lamps and electronic ballasts, had lighting controls in the form of window blinds for sunlight, and for electric light they had manual dimmers, occupancy sensors and photosensors. Some offices had dimmers on their desks. Some of the dimming systems were equipped with an auto-restore feature that, when an occupant returned to his office, would reset the lighting to the level where the occupant had previously set it. Occupants were also given questionnaires to explore their response to the technologies and the reasons behind their lighting adjustments. The study showed that individuals varied in their use of dimming. Some adjusted their lighting levels several times a week, but on average, they adjusted their lighting once a week. Their first move was to adjust window blinds to block the sunlight; then they would adjust the electric lighting levels. None of them adjusted their lighting to save energy.

The study's conclusions suggest some ideas you could use to help customers optimize lighting control applications. The data suggest that auto-restore motion sensors and manual switching and dimming maximizes occupant satisfaction and minimizes wasted energy in private offices. Motion sensors reduced wasted lighting energy by turning lights off when no one occupied the office, and a shorter delay time would further reduce wasted energy, but it may also cause occupant dissatisfaction.

The use and acceptance of these technologies is on the rise, according to manufacturers, though sophisticated lighting controls are still far from becoming the norm in new construction. Companies keeping an eye on energy efficiency and total operating costs have already embraced lighting control technologies, says Jerry Mix, president of The Watt Stopper, Inc., San Jose, Calif. "For the companies looking at it and saying, 'What is our return on investment?' the acceptance level is there. But the companies that say, 'What is the lowest-cost way I can build my building?'-the acceptance doesn't exist." Manufacturers are promoting the benefits of lighting controls. more heavily than ever and are campaining for standardized testing and evaluation of their products. The National Electrical Manufacturers Association (NEMA), Rosslyn, Va., has a group called the Lighting Controls Council which is not a standards-making body, but is a forum for sharing information of common interest. The council is pursuing an occupancy-sensor standard test procedure and an international dimming-ballast standard as well as promotional efforts to raise awareness of lighting controls' benefits.

The sales potential in lighting controls certainly has captured the awareness of manufacturers. Over the past three years, some major wiring device companies have expanded their lighting control business through acquisitions. For example, Pass & Seymour/Legrand, Syracuse, N.Y., bought The Watt Stopper in January 1996, and Leviton Manufacturing Co., Little Neck, N.Y., in July 1997 bought a company called Macro Electronics Corp., Austin, Texas, a specialist in architectural dimming systems.

Here are some of the latest developments for each of the product categories in the dimming market:

Time controls. Timers may be the oldest form of automatic lighting control, and their function has been taken over by newer technologies in many applications, but they still have a role to play in the commercial market. They're used primarily for outdoor lighting where on/off cycles are predictable. Where the mechanical timers of old had to be adjusted periodically, the introduction of digital technology has made timers more versatile, opening up new possibilities for programming scenarios and scheduling.

Dimming controls. Technology for dimming fluorescent lamps is full of technical difficulties having to do with the need to keep enough power going to the electrodes to keep the phosphors active. While dimming ballasts have been on the market for several years, only recently have manufacturers offered the levels of functionality and reliability that users want. Now that the technology is there, it's still fairly expensive-a dimming ballast can be twice the cost of a non-dimming ballast-and because of the cost it's difficult to sell dimmers on the energy savings alone.

However, other benefits exist with dimming, as is suggested by the LRC's research at the NCAR building. Manufacturers with interests in dimming are mounting a new campaign to boost awareness of the benefits of dimming. Along with most of the rest of the technological world, dimming controls have made atransition from analog to digital, giving them broader and finer functionality. While the brain of the dimmer will remain digitally controlled, though, there is a trend back toward analog interfaces because of their intuitive simplicity, says David Harrison, vice president of Leviton's Lighting Controls division.

Anyone who has tried to adjust the lighting in a conference room with a digital control panel knows they are far from intuitive. For that reason, Leviton is designing more controls with easily understood analog controls such as sliders that operate digital innards.

Occupancy sensors. Two general technologies are used in occupancy sensors-infrared and ultrasonic. Each has its strengths and weaknesses. Roughly speaking, infrared is good at detecting large motions, such as a person moving about in an office, but is not as good at detecting fine motions such as hand and wrist movements. Therefore it is more likely to shut off the lights if an office's only occupant is sitting still in front of a computer. Ultrasonic sensors are good at detecting fine motions, but are more susceptible to false trips. Some companies have developed dual-technology sensors that use both infrared and ultrasonic to double-check one another, including desktop sensors that can control an individual's lighting with more accuracy.

Thus far, the industry has developed no standards for testing occupancy sensors, though the NEMA Lighting Controls Council is laying the groundwork. Maniccia of the LRC has done some research on testing occupancy sensors using a robot arm to ensure repeatable tests in terms of speed and motion.

Photosensors. Photosensors are often used with dimmers to coordinate electric lighting with daylighting from windows and skylights. This approach has the benefit of maximizing natural light, to which many people attribute healthful benefits, as well as efficiency. Photosensors are only beginning to scratch the surface of their possible applications in lighting control, especially as daylighting becomes a more popular and effective lighting technique.

Photosensors have many applications in open-office lighting systems and public spaces, but they turned out not to be very practical in the enclosed offices at the NCAR building, according to Maniccia. The building managers installed them and commissioned them, but occupants objected to the automatic control and said they preferred to set their own light levels, she says. In response, NCAR paid to have the sensors recommissioned to dim so slightly they were basically disabled.

One of the tricks with photosensors that distributors need to be aware of is that they're not universally compatible with dimming ballasts. The signals sent out by some sensors are not effective with some ballasts. LRC is currently doing research on the problem and looking at ways to identify compatible systems. Building management systems. The spread of building management systems is another major factor driving the commercial lighting controls market. The ability of these systems to track and report on lighting and other systems such as heating and cooling makes them powerful tools for customers wanting to optimize their energy usage.

Building mangement systems that control lighting as well as other systems such as heating, ventilation and air conditioning (HVAC), security and so forth, allow tracking of events, creation of scenarios based on use of the space or utility billing rates or what have you, troubleshooting and maintenance scheduling and remote diagnostics.

At the current stage of the technology's development, whole-building management systems are good as macro controllers, but typically won't control lighting at the desktop level, because it's expensive and too cumbersome to control so many small devices, says Harold Jepsen, product line manager for lighting control panels at Watt Stopper. "It's usually not worth the added cost to have a controller manipulate every individual sensor and fixture in a system," he says. "Occupancy sensors on the other hand are a good micro controller." Often a smaller lighting control system will let users handle lighting, and that system will be integrated with the building management system.

One major sticking point is the conflict over communications protocols used in these systems. A number of proprietary protocols have evolved, and there are two competing standards that are more or less open-BACNet and LONWorks-plus a handful of proprietary standards. BACNet, also known as ANSI/ASHRAE standard 135-1995, is an open standard developed by the American Society of Heating, Refrigerating and Air-conditioning Engineers (ASHRAE). LONWorks is a distributed-control standard developed by Echelon Corp., Palo Alto, Calif., that has gained widespread support in various automation areas, including home, factory and building automation.

The conflict in standards makes problems for manufacturers, who must design their devices to interact with one or the other, and finding the solution that will support the broadest market segment is difficult. Everyone contacted for this story agreed that the industry needs to work out a solution to the standards problem, but thus far there seems to be little movement.

Overall trends. Products are becoming more intelligent. "Anything that goes in a wall is changing from something that does not have intelligence to something that does," says Harrison of Leviton. "I see things leaning more toward the system. Hopefully, anything that we design that goes into a wall will ultimately be part of a system." He believes end users and installers want dimming equipment that easily integrates into a system.

Customers are becoming more intelligent, too. Historically there has been a widespread aversion to lighting controls. In some people's minds, devices such as occupancy sensors, photosensors and building management systems are still unreliable technologies that are little more than fancy add-on toys that drive up the cost of a building. A central bank of on-off switches operated by the janitor worked just fine for generations, and the money saved helped the builder make more profit.

For those customers who remain stubbornly unconvinced about the benefits of lighting controls, there's the long arm of regulatory law to help out. Energy efficiency requirements written into building codes and regulations in some states offer some. help in promoting the more rudimentary controls such as timers. Several states require every commercial building to have a system to automatically shut off the lights after the close of business. In some cases, the systems must also have the ability to be overridden by occupants if they're working late.

Distributors can capture several advantages by focusing more attention on lighting controls. For one thing, lighting controls and other energy management products tend to do well in a down economic cycle. When construction work dries up, contractors and distributors need to make as much incremental money on each project as they can, and lighting control systems are good add-on sales. They also help the end-users control their costs.

Distributors who creatively sell lighting jobs can capture add-on sales. For instance, if a distributor gets a contractor to install a dimming ballast in one office, co-workers may want to know why that person got the dimmer and they didn't, driving follow-up sales.

Lighting controls are a growth market for distributors, say manufacturers. In projects that don't have controls in the original specs, it's an opportunity for wholesalers to add value by helping customers save money and improve productivity.

About the Author

Doug Chandler | Senior Staff Writer

Doug has been reporting and writing on the electrical industry for Electrical Wholesaling and Electrical Marketing since 1992 and still finds the industry’s evolution and the characters who inhabit its companies endlessly fascinating. That was true even before e-commerce, LED lighting and distributed generation began to disrupt so many of the electrical industry’s traditional practices.

Doug earned a BA in English Literature from the University of Kansas after spending a few years in KU’s William Allen White School of Journalism, then deciding he absolutely did not want to be a journalist. In the company of his wife, two kids, two dogs and two cats, he spends a lot of time in the garden and the kitchen – growing food, cooking, brewing beer – and helping to run the family coffee shop.

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