The LED industry is in the midst of a rapid development cycle. In an effort to lengthen bulb lifetime, intensify colors, and create higher energy efficiencies, manufacturers are developing LEDs at an intense rate.
To help Building Team members sort through the new technological dimensions of LEDs, we asked two top-rated LED experts—John W. Curran, PhD, president of LED Transformations LLC, an LED industry consulting firm based in Stanton, N.J., and Glenn Heinmiller, principal of LAM Partners Inc., an architectural design firm based in Cambridge, Mass.—for their advice.
1. Pencil out the economics of LEDs. Building Teams should evaluate the economics of deploying LED luminaires. Cost savings come from two factors: energy efficiency and long life. The higher the electric utility rate for the application, the faster the payback. A long lifespan provides reduced maintenance costs resulting in additional savings. “The LED fixtures must last as long as assumed in the ROI calculations,” says Curran. “This is often where the economics for LED fixtures falls apart.” According to Curran, Building Teams must also be careful not to assume a lifetime that the fixtures do not deliver due to bad information from the fixture manufacturer or misapplication by the specifier or contractor.
2. Determine if LEDs are the right application for your building. “The answer depends on the specific lighting application, local electricity rates, operating hours, maintenance costs, and availability of utility incentives,” says Heinmiller. Building Teams should help owners explore the length of the payback period versus best energy performance regardless of upfront cost.
3. Consider the physical environment immediately surrounding the LEDs. Very high-temperature environments can present problems for LED technology. For example, installing highbays in an uncooled warehouse in Arizona may result in greatly reduced lifetimes for the LEDs. Those same highbays in a cold storage facility will perform much better.
4. Be aware that dimming is still a major problem with LEDs. Not all LED products can be dimmed, and those that can may not dim smoothly or to a low level. This is due to the widespread use of phase-cut dimmers in concert with conventional incandescent lighting and the drivers—the electronics—that power the LEDs. “It’s not easy to predict how a particular driver will perform against a wide range of dimmers already installed,” says Curran. Currently, there are no standards for LED dimming control, so only certain types of dimmers or dimming protocols will work with a particular LED fixture. “Dimming problems will probably improve some with technology development, but there are no signs the industry is standardizing on a dimming protocol,” says Heinmiller.
5. Test the LED color rendition. “The color rendering performance of white LED sources is generally quite good,” says Heinmiller. “Testing is important, especially for applications where color rendition is crucial, in order to make sure you are satisfied with the results.” Eventually, there will be an improved color metric that will predict quality more accurately from the specifications. Until then, Building Teams should advise clients to test color-critical applications.
6. Check out the fixtures with the manufacturer. Ask the LED manufacturer about their quality control and the type of testing done on their drivers. Deal only with reputable suppliers and manufacturers: What good is a 10-year warranty when the supplier goes out of business in a few years? Ask the supplier how they plan to provide replacement fixtures in 3 to 5 years.
7. Look for the Lighting Facts label. Go to www.lightingfacts.com to learn about a U.S. Department of Energy program that showcases LED products for general illumination from manufacturers who commit to testing products and reporting results according to industry standards. The LED Lighting Facts label can provide Building Teams with essential information for evaluating products and identifying the best options.
8. Go with a pro. For complex projects, engaging the services of a qualified professional architectural lighting designer could save your client—and you—a lot of money and grief. “It is a complex problem to determine the correct light source for the application in order to achieve the best energy efficiency and high lighting quality,” says Heinmiller. If you focus only on lower energy efficiency, you could end up with a lower electric bill but poor lighting in your building—or worse, no savings and poor lighting. For projects such as relamping existing track lighting in a retail store, working with a respected manufacturer’s representative who supports mockups and stands behind the supplier’s LED products is probably sufficient.
What are OLEDs?
Organic light-emitting diodes (OLED) are a separate branch of solid-state lighting that are beginning to have an impact on the architectural lighting industry. “The major performance difference between LEDs and OLEDs is that LEDs are point light sources while OLEDs are area sources,” says Curran, president of LED Transformations. LEDs are much further ahead in regard to cost, higher efficiencies, and longer lifetimes. Currently, OLEDs are used in cell phone displays and a small but growing number of high-end designer lighting fixtures.
Learn more about LED standards
• ANSI C78-377-2008 Specifications for Chromaticity of Solid-State Lighting Products for Electric Lamps. ANSI C78-377-2008 provides a standard for qualifying the range of colors that can be classified a particular color temperatures.
• LM 79-08 Approved Method: Electrical and Photometric Measurements of Solid-State Lighting Products. LM 79-08 gives the proper test procedure to evaluate light distribution and power consumption for an LED fixture. LED fixtures require special testing (using absolute photometry) because LED light sources, unlike traditional sources, cannot be tested independent of the fixture due to thermal effects on performance.
• LM 80-08 Approved Method for Measuring Lumen Depreciation of LED Light Sources; and TM-21-11 Projecting Long-Term Lumen Maintenance of LED Sources. LM-80-08 and TM-21-11 provide guidance on measuring and predicting the lumen depreciation of LED devices, which yields an estimate of useful lifetime.
Related Stories
| Apr 13, 2011
Office interaction was the critical element to Boston buildout
Margulies Perruzzi Architects, Boston, designed the new 11,460-sf offices for consultant Interaction Associates and its nonprofit sister organization, The Interaction Institute for Social Change, inside an old warehouse near Boston’s Seaport Center.
| Apr 13, 2011
Expanded Museum of the Moving Image provides a treat for the eyes
The expansion and renovation of the Museum of the Moving Image in the Astoria section of Queens, N.Y., involved a complete redesign of its first floor and the construction of a three-story 47,000-sf addition.
| Apr 13, 2011
Duke University parking garage driven to LEED certification
People parking their cars inside the new Research Drive garage at Duke University are making history—they’re utilizing the country’s first freestanding LEED-certified parking structure.
| Apr 13, 2011
Red Bull Canada HQ a mix of fluid spaces and high-energy design
The Toronto architecture firm Johnson Chou likes to put a twist on its pared-down interiors, and its work on the headquarters for Red Bull Canada is no exception. The energy drink maker occupies 12,300 sf on the top two floors of a three-story industrial building in Toronto, and the design strategy for its space called for leaving the base building virtually untouched while attention was turned to the interior architecture.
| Apr 13, 2011
Former department store gets new lease on life as MaineHealth HQ
The long-vacant Sears Roebuck building in Portland, Maine, was redeveloped into the corporate headquarters for MaineHealth. Consigli Construction and local firm Harriman Architects + Engineers handled the 14-month fast-track project, transforming the 89,000-sf, four-story facility for just $100/sf.
| Apr 12, 2011
Rutgers students offered choice of food and dining facilities
The Livingston Dining Commons at Rutgers University’s Livingston Campus in New Brunswick, N.J., was designed by Biber Partnership, Summit, N.J., to offer three different dining rooms that connect to a central servery.
| Apr 12, 2011
Retail complex enjoys prime Abu Dhabi location
The Galleria at Sowwah Square in Abu Dhabi will be built in a prime location within Sowwah Island that also includes a five-star Four Seasons Hotel, the healthcare facility Cleveland Clinic Abu Dhabi, and nearly two million sf of Class A office space.
| Apr 12, 2011
Luxury New York high rise adjacent to the High Line
Located adjacent to New York City’s High Line Park, 500 West 23rd Street will offer 111 luxury rental apartments when it opens later this year.
| Apr 12, 2011
College of New Jersey facility will teach teachers how to teach
The College of New Jersey broke ground on its 79,000-sf School of Education building in Ewing, N.J.
| Apr 12, 2011
Mental hospital in Boston redeveloped as healthcare complex
An abandoned state mental health facility in Boston’s prestigious Longwood Medical Area is being transformed into the Mass Mental Health Center, a four-building mixed-use complex that includes a mental health day hospital, a clinical and office building, a medical research facility for Brigham and Women’s Hospital, and a residential facility.