On three faces of the new downtown Los Angeles headquarters of the California Department of Transportation (Caltrans), 2,000 innovative outdoor metal panel scrim louvers open and close in vertical banks. With the arrival of employees at 8 a.m., west- and north-facing louvers open, providing the maximum amount of daylight for inside work spaces, before the rays of the sun hit and warm the western face. The east-facing scrim louvers stay closed. The louvers provide a chimney effect for heat from the sun to be drawn up and out the top between the scrim and building glass. When afternoon sun strikes the western face, its scrim closes and those on the east face open, reversing the process. This programmed design allows for the harvesting of daylight, while minimizing the impact of sun-generated heat, thus decreasing the need for air conditioning.
Inside the $200 million, 750,000-square-foot building, which opened in September 2004, fixtures above work cubicles respond to light-sensor levels; these lighting fixtures automatically turn on, dim or turn off depending on ambient daylight. Motion sensors control the lights depending on occupancy. On the southern side of the 13-story building is a large photovoltaic array that sends power back to the building. All the features result in a 20 percent decrease in energy costs-a savings of $140,000 annually.
New energy standards
The Caltrans building complies with the Leadership in Energy and Environmental Design (LEED) Green Building Rating System-a voluntary, consensus-based national standard for developing high-performance sustainable buildings-and in doing so gains LEED points by exceeding the Energy Star base set by the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE). As such it incorporates some of the latest trends in the commercial lighting industry: harvesting of daylight, use of efficient products and control systems that monitor occupancy and light, and ongoing contributions back to the power grid.
“The biggest change in commercial lighting is energy conservation,” said Henry Turner, project manager, Dynalectric, the Caltrans building's electrical contractor.
And that also amounts to cost savings. Yet, while LEED standards are voluntary, it is legislation-the energy standard known popularly as ASHRAE 90.1, which takes full effect in 2005 for all 50 states-that is really pushing the trends. The standard calls for more stringent lighting power requirements, required use of lighting controls for many situations, and ballasts for certain lamps to be electronic types only. Initiatives, like that of International Dark-Sky Association, are also influencing the trends.
With the call for energy savings on a per-square-foot basis, many businesses are reconsidering use of different technologies. In retail settings, some but not all retailers can live with restrictions.
“Some large retailers use fluorescents for a uniform light and can achieve it using 1.9W psf [per square foot]. But you walk in a mall and some stores are using incandescent lights, 6 to 8W psf to get the drama they need for mannequin heads and end-counter displays,” said Mark Lien, manager, Specification Marketing, Cooper Lighting/SOURCE. “They give you a narrow focus for drama. Yet the trend in the last two years for national chains is to switch out those incandescent to a new metal halide source called a T4 lamp in track and down-lighting, because it is operating at three times the efficiency while generating one-third to one-fourth of the heat. The AC then works better and is less expensive.”
In industrial settings, metal halide has been the dominant source.
“There's now a movement toward use of linear fluorescent in warehousing and assembling areas,” said Phil Henry, VP, marketing, Genlyte Supply Division, “because the color-rendering properties of metal halide is 65, while the T5HO is 85. The closer it is to daylight , there's a perception that it's a better light, even if it is not any brighter. Another reason is because it's an instant-on. A HID source requires five minutes to come up to full brightness and 15 [if] it has been turned off. So you can use the linear fluorescent to turn the lights on and off with motion sensors if the warehouse is not being used. And linear fluorescents have a higher lumen maintenance factor over the life of the lamp. The T5 loses only 5 percent over 20,000 hours while the metal halide loses 35 percent of the rated lumen over the life of the lamp.
“Another trend,” Henry added, “is adoption of more efficient bulbs. Years ago it was T12, then T8 and now T5.”
Lithonia has recently released the RT5-a new fixture for use in commercial structures designed to replace parabolic louvers-which uses T5 technology and only two lamps, providing a 33 percent savings in energy over a standard 18 cell, three-lamp T8 parabolic. Ushio America Inc. released the first T15 pulse start lamp in its PulseStrike T15 Metal Halide Lamp.
Keith Hartman, of Public Energy Solutions, said, “T5 and T8 high-bay fixtures can achieve savings of 25 percent to 50 percent from existing systems with improved light levels and aesthetics.”
Eye-pleasing and nonpolluting
Aesthetically pleasing fixtures are now in high demand.
“The appearance of outdoor lighting … has taken on an architectural look,” added Henry. “People don't want traditional-looking fixtures.”
Tied into that is a push for increased awareness of the effect of light pollution, which is being led by the International Dark-Sky Association-a tax-exempt, nonprofit organization formed in 1988.
“Light fixtures that throw light up are being legislated out of existence in the U.S. and other countries,” said Lien. “That creates problems since the light doesn't spread out, so we have to use more energy, which conflicts with ASHRAE. It's changed the way we design fixtures. Fixtures in our new InVue line are almost all dark-sky compliant. It's a challenge for our optical engineers to make the light spread out but not up.”
Henry concurred, adding: “People don't want to waste light because energy costs are high and because of concern with light pollution.”
One product, Stonco's FloodPak, addresses both the architectural issue and the light issue, directing light below 90 degrees by allowing for different rotations-a semi-cutoff luminaire at a 22.5-degree rotation or a 45-degree rotation for floodlighting or reversed for indirect/accent lighting.
As businesses implement changes, some are also realizing the economic value of the changes. “As recently as a year ago most of our installations were Code-driven,” said David Wilson, president, Lighting Control & Design. “Now, even when not required by Code, clients are ordering controls because they see they are saving money. By installing both energy-efficient lights and controls that ensure they are only on when they need to be, they can save money and help the environment. It's really an attitude change.
“On a bright, sunny day most daylight harvesting systems work without problem,” said Wilson, whose company won a Lightfair 2004 award for its lumen maintenance photocell (LMPC). “On an overcast day, there's complexity to control. A light change can be jarring to customers, and some clients respond by bypassing the system. That upsets management who has invested in a system but doesn't get the expected savings. With LMPC, we were aiming to give more control of the setup and calibration of the system.”
However, this market is changing quickly, and Lighting Control & Design has since replaced LMPC with a more advanced product, the GR 2404-iDim and the iPC, a digital solution. With no change in hardware or price, it incorporates a software change and gives 10 more parameters of control.
Electrical contractors are being asked to stay abreast of changing technology. That can be a challenge.
“With control systems, the issue for the electrical contractor is often where to put the photocell,” said Wilson. “Sometimes it is on the plans, but most frequently it isn't because it is a fairly new area and electrical engineers are not yet familiar with where to best place them. And even if they are placed correctly, there can be unexpected changes. The company lays a new carpet, it's a dark color and then everything is wrong. With our new system, we can reprogram it remotely for free. That gets around the problem of the electrician having to go back and recalibrate.”
As the technology changes, so does the job of the electrical contractor. Old jobs go, yet new jobs emerge. For the Caltrans building, the scrim louvers were architectural features used to harvest daylight. To implement the system, Dynalectric was called on to help design the pneumatic cylinders and the catch and release system, something never done before.
Electrical contractors can also create their own job opportunities by staying abreast of new products and advances; by noting the awards given by lighting designers at Lightfair, an annual lighting trade show (http://www.lightfair.com/); and by viewing the annual progress report of IESNA, which awards products for progressive technology (http://www.iesna.org/programs/progress_report.cfm). (See box on page 75.)
One Lightfair 2004 best of category winner was GE Lighting's Value Light tool, a product that allows one to analyze the cost of operating and owning a lighting system by comparing different systems and pointing out the best alternatives.
According to Dynalectric's Turner: “We can go into a facility that does have existing light, look at the provided light, measure light levels and provide information on how the facility can be retrofitted and how the retrofit can save the end-user energy by getting rid of the old lights and bringing them into the new technology. That's a job avenue that can be explored by the electrical contractor.”
So what's next?
“Millions of dollars of government grants are being invested in LED research,” said Lien.
It shows. At Lightfair, the number of LED and LED-based product exhibitors more than doubled from 2003 to 2004.
“Electrode-less lamps are becoming more affordable and research is being done in how to make light with sound waves, in architectural lighting with lasers, and there's techniques being used to try to generate light with light-emitting polymers,” said Lien. “Photobiology, the effect of light, is another area. The Lighting Research Center says this is the future for all lighting research. It's a serious area that's going to drive a lot of new fixtures.”
And then there's globalization.
“There's no one player that dominates the worldwide lighting market,” added Lien. “One of the reasons is that standards used in different countries vary dramatically, so we are trying to get to a point where we have international standards. Once we do, American players will compete in the global marketplace and other companies will come into our market.” EC
CASEY, author of "Kids Inventing! A Handbook for Young Inventors" and "Women Invent! Two Centuries of Discoveries that have Changed Our World," can be reached at email@example.com or www.susancaseybooks.com.