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
| Jun 30, 2014
Research finds continued growth of design-build throughout United States
New research findings indicate that for the first time more than half of projects above $10 million are being completed through design-build project delivery.
| Jun 30, 2014
Narrow San Francisco lots to be developed into micro-units
As a solution to San Francisco’s density and low housing supply compared to demand, local firms Build Inc. and Macy Architecture each are to build micro-unit housing in a small parcel of land in Hayes Valley.
| Jun 30, 2014
Arup's vision of the future of rail: driverless trains, maintenance drones, and automatic freight delivery
In its Future of Rail 2050 report, Arup reveals a vision of the future of rail travel in light of trends such as urban population growth, climate change, and emerging technologies.
| Jun 30, 2014
4 design concepts that remake the urban farmer's market
The American Institute of Architects held a competition to solve the farmer's markets' biggest design dilemma: lightweight, bland canopies that although convenient, does not protect much from the elements.
| Jun 30, 2014
Harvard releases the State of the Nation’s Housing 2014
Although the housing industry saw notable increases in construction, home prices, and sales in 2013, household growth has yet to fully recover from the effects of the recession, according to a new Harvard University report.
| Jun 30, 2014
OMA's The Interlace honored as one of the world's most 'community-friendly' high-rises
The 1,040-unit apartment complex in Singapore has won the inaugural Urban Habitat award from the Council on Tall Buildings and Urban Habitat, which highlights projects that demonstrate a positive contribution to the surrounding environment.
| Jun 30, 2014
Work starts on Jean Nouvel-designed European Patent Office in the Netherlands [slideshow]
With around 80,000 sm and a budget of €205 million self-financed by the EPO, the complex will be one of the biggest office construction sites ever in the Netherlands.
| Jun 30, 2014
Growth of crowdfunding, public-private partnerships among top trends in architecture marketplace
A new report by the American Institute of Architects highlights several emerging trends in the architecture marketplace, including the growth of the P3 project delivery model and designing for health.
| Jun 30, 2014
Report recommends making infrastructure upgrades a cabinet-level priority
The ASCE estimates that $3.6 trillion must be invested by 2020 to make critically needed upgrades and expansions of national infrastructure—and avoid trillions of dollars in lost business sales, exports, disposable income, and GDP.
| Jun 30, 2014
Gen X, not Baby Boomers, spending the most money on homes [infographic]
It turns out that Generation X, who have the highest incomes of the three generations surveyed, are paying the highest home payments and tend to have the largest households.