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
| May 7, 2014
Design competition: $900,000 on the line in Las Vegas revitalization challenge
Las Vegas Mayor Carolyn Goodman wants your economic development ideas for remaking four areas within the city, including the Cashman Center and the Las Vegas Medical District.
| May 6, 2014
'Beyond' is artist's cinematic take on 2.5 years of development in the UAE
Seven-minute video offers a time-lapse trip through the built environments of Abu Dhabi and Dubai.
| May 6, 2014
'Ugliest building in New Jersey' finally getting facelift
After a decade of false starts and mishaps, the American Dream mall in the Meadowlands may finally get built.
| May 5, 2014
Toronto residential tower to feature drawer-like facade scheme
Some of the apartments in the new River City development will protrude from the building at different lengths, creating a drawer-like "push-pull" effect.
| May 5, 2014
Tragic wired glass injury makes headlines yet again
In the story, a high school student pushed open a hallway door glazed with wired glass. His arm not only broke the glass, but penetrated it, causing severe injuries. SPONSORED CONTENT
| May 3, 2014
Health system capital planning for the future: The benefits of master plan portfolio analysis and ambulatory market modeling
Money continues to be scarce, yet U.S. health systems need to invest and re-invest in their physical future. Healthcare facilities planning experts from CBRE Healthcare outline tools and strategies for identifying where to best allocate precious resources.
| May 3, 2014
4 easy steps to being a great project manager
Managing a team of people, especially creative people, is a task that not everyone is up for. Keeping your team on the same page while maintaining a schedule and budget that can keep your corporation happy will take confidence and bountiful people skills. Here are some tips for effectively managing a project. SPONSORED CONTENT
Sponsored | | May 3, 2014
Fire-rated glass floor system captures light in science and engineering infill
In implementing Northwestern University’s Engineering Life Sciences infill design, Flad Architects faced the challenge of ensuring adequate, balanced light given the adjacent, existing building wings. To allow for light penetration from the fifth floor to the ground floor, the design team desired a large, central atrium. One potential setback with drawing light through the atrium was meeting fire and life safety codes.
| May 2, 2014
World's largest outdoor chandelier tops reworked streetscape for Cleveland's PlayhouseSquare
Streetscape project includes monumental gateway portals, LED signage, and a new plaza, fire pit, sidewalk café, and alfresco dining area.
| May 2, 2014
Norwegian modular project set to be world's tallest timber-frame apartment building [slideshow]
A 14-story luxury apartment block in central Bergen, Norway, will be the world's tallest timber-framed multifamily project, at 49 meters (160 feet).