According to the U.S. Environmental Protection Agency’s (EPA) Energy Star program, lighting consumes 25 to 40 percent of the energy used in commercial buildings and is a primary source of waste heat. In addition, lighting within buildings accounts for 23 percent of national electrical consumption and, of the total national lighting energy used, commercial lighting accounts for 60 percent, residential 20 percent, industrial 16 percent, and outdoor (street) and other uses make up the last four percent.
Concerns over rising energy costs and conservation needs have owners of commercial buildings, industrial plants and residential homes demanding more energy-efficient lighting selections.
According to David Weigand, product manager for energy management controls at Leviton Manufacturing Co. Inc., Little Neck, N.Y., the most major advancement in energy-efficient lighting is in the area of communication between lighting controls and other building systems.
“Improved software is being written to provide increased integration between lighting and HVAC and security systems, allowing occupants to better control their personal environments,” he said.
Communication protocols, such as digital addressable lighting interface (DALI), allow occupants to control every light fixture separately, either through computer or manual controls, thereby easily identifying patterns of use and increasing energy savings.
“In applications such as multitenant buildings, DALI provides building owners and tenants with the ultimate flexibility for their lighting requirements without rewiring the space,” Weigand said.
Lamp sources, such as compact fluorescent lamps (CFLs) have gotten small enough to fit into the same footprint as regular incandescent bulbs. They have also become bright enough to provide bright light, warm colors and near-perfect color rendition, said Tim Wyatt, marketing manager for Maxlite, Pine Brook, N.J.
“A 15-watt CFL will generally produce as much light as a 60-watt incandescent bulb, which provides up to 75 percent in energy costs,” Wyatt said.
CFLs last up to 10,000 hours, thus reducing replacement costs and further increasing overall savings.
Cold cathode light sources are increasingly being used for decorative, marquee and outdoor lighting applications. Instead of having a filament that needs to warm up, cold cathode lights have a single rod of metal with instant starting capabilities.
According to Jeff McDonald, national sales for linear fluorescent at Technical Consumer Products Inc. (TCP), Aurora, Ohio, cold cathode lights currently do have lower efficacy than either CFL or fluorescent sources.
“They are, however, extremely efficient compared to incandescent lights, with an only 3-watt cold cathode light required to replace a 15- to 20-watt incandescent bulb,” he said.
The latest iteration of T8 lamps, including the T8HO, are now providing the same light output as their predecessors for less energy, or even more light output for the same energy consumption levels as before.
“The lighting industry is focusing on creating more efficient lamps, rather than on lamp size,” said Ken Walma, marketing manager for Lutron Electronics Inc., Coopersburg, Pa.
The new T4 and T6 metal halide lamps are low-wattage alternatives to incandescent or halogen lights in a small package.
“These lights have smaller apertures and can be used in smaller fixtures, while saving up to three times as much energy as incandescent lights,” said Melissa Hertel, specification marketing manager for Lightolier Inc., a Genlyte Group company in Fall River, Mass.
Light emitting diodes (LEDs) have come a long way since first used as indicator lights in cars or in consumer electronics. Newly developed white LEDs are increasingly being used in some general lighting applications.
“White LEDs are now producing warm light in a consistent manner,” Wyatt said.
One problem with LEDs, however, is that they don’t throw much light. Manufacturers are currently working with the reflectors and the glass lenses to overcome this particular characteristic.
“By shaping the light with the reflector and the lens, manufacturers are trying to provide diffusion to create general, rather than high-beam, intense-focus light,” Wyatt said.
In general illumination, white LEDs have important significance for the future because they last up to 50,000 hours, use very little power to operate and have reduced maintenance and replacement costs.
Ballasts and controls
According to McDonald, the continued expansion of electronic ballasts has allowed electrical contractors to maximize energy savings or light output, depending on the ballast factor chosen for the application.
“Electronic ballasts give the contractor more flexibility to provide the lighting environment required by the end-user while meeting both energy and illumination goals,” he said.
Digital controllable ballasts are the next step and are being seriously discussed, said Walma.
“Where DALI was the first generation of digital ballast technology in the U.S., new products with more enhanced digital ballasts will allow greater flexibility and the ability to incorporate energy efficient-lighting in a space, while eliminating hardware such as dimmers, dimming panels and interfaces,” he said.
According to Wyatt, the next big breakthrough for CFL ballasts, will be the development of ballasts with components that have high-heat resistance.
“CFLs are high-heat light sources. Sometimes the resistor is the weak link and sometimes it is the shielding. The most successful heat reduction method will probably be cooling the air flow,” Wyatt said.
Ballasts will get lighter and smaller, while universal ballasts for linear fluorescent lighting, which will operate at either 120- or 277-volts, will drive multiple combinations of fluorescent lamps.
Lighting fixtures are becoming intelligent, with state-of-the art, digital technology that allows them to control, as well as monitor, lamp and ballast performance and energy consumption through existing LANs, without complicated component parts and no custom software interfaces.
“This will allow control of the environment to be put into the hands of individual users, since each ballast will be addressed separately,” Hertel said.
Although the technology has existed for almost a decade, wireless lighting controls (WLCs) have really started to make major inroads in the last two years, particularly in residential applications.
“The awareness of the benefits of lighting controls has increased as customers try to save energy and improve the aesthetics of their homes,” Walma said.
Using wireless control devices allows homeowners to retrofit their lighting controls more easily. Even in new construction, WLC technology allows homeowners to add additional lighting control features without making any changes to the wiring design.
The amount of light per watt that can be produced for a space has been pushed to the limit in national and regional energy codes across the nation. The way to save energy will now be the more efficient use of the light being produced, Weigand said.
“This will most likely be accomplished through the development of more sophisticated occupant-responsive controls that reduce lighting according to ambient conditions, “he said.
California’s Title 24 became effective in October 2005 and requires dimmers or occupancy sensors for incandescent fixtures. These building standards were developed to respond to California’s energy crisis, reduce energy bills, increase energy-delivery system reliability and improve the state’s economic condition. For many of the same reasons, other jurisdictions are beginning to require occupancy sensors in buildings of various sizes.
The primary goals of energy-efficient lighting are energy management, high performance and sustainability. Building owners, architects and engineers are incorporating energy-efficient lighting sources into their designs that are controlled through dimming ballasts, daylight harvesting and occupancy sensor technology, as these are the methods of saving energy that are being awarded by Leadership in Energy and Environmental Design (LEED) -directives.
The most proactive electrical contractors, according to Walma, are the ones that learn the most they can about controls in order to properly incorporate and install energy-efficient lighting.
“As LEED and new energy codes drive us toward more efficient buildings, electrical contractors that embrace these technologies and that understand their applications will be the ones that are best able to differentiate themselves in the market,” Walma said.
Electrical contractors should also know about the various incentive and rebate programs that are in their area so that they can encourage their customers to consider energy-efficient lighting.
“But they have to have the necessary knowledge to demonstrate the benefits and cost savings,” Wyatt said.
There are, of course, trade-offs between energy efficiency and light levels. McDonald said contractors need to understand exactly what the equipment is designed to deliver to better counsel and guide the end-user in making their choices.
“Contractors should try to get customers to actually come and see the lighting being considered in operation, whether at the site or in a trial installation,” he said.
Such service could help the contractor gain an advantage in the market, estimate jobs more efficiently and allow the customer to appreciate what the particular lighting system will actually -deliver.
Finally, electrical contractors need to have a firm grasp on the available options for energy-efficient lighting that manufacturers offer and what the design community tends to include in their plans and specifications.
“It’s extremely helpful to ensure proper start-up and commissioning of a lighting project to understand what the particular products and systems are intended to accomplish and what their overall capabilities are,” Weigand said.
Future developments in areas such as organic LEDs, integrated LED lighting systems, and intelligent and wireless controls will provide electrical contractors with the opportunity to ensure that their customers receive the most efficient and cost-effective lighting possible. EC
BREMER, a freelance writer based in Solomons, Md., contributes frequently to ELECTRICAL CONTRACTOR. She can be reached at 410.394.6966 or firstname.lastname@example.org.