After Jeff McCullough's talk at Intertech’s LEDs October 2007 conference, an audience member declared that McCullough’s employer, the U.S. Department of Energy (DOE), is “taming the Wild West” and suggested that he wear a cowboy hat.
McCullough, LC, CLEP, is a senior research engineer for the DOE’s Pacific Northwest National Laboratory. His presentation detailed a new Energy Star specification that will become effective Sept. 30, 2008, covering certain light emitting diode (LED) fixtures. The “Wild West” being referred to is the market and technology that have evolved more rapidly than critical standards for testing and representing products could, resulting in inaccurate product information and an associated lack of confidence.
The Wild West
Widespread adoption of rapidly developing LED technology requires a level of confidence that, in turn, requires industry standards that, in some cases, take years to create. Many new standards are needed because LEDs behave differently than other light sources and, therefore, must be tested and represented differently. Without these standards, manufacturers may knowingly or unknowingly overstate the performance of their products.
For example, the DOE tested 50 LED downlights, task lights, undercabinet fixtures, outdoor fixtures, replacement lamps and other products in 2007, using the Illuminating Engineering Society of North America (IESNA) LM-79 testing standard (a draft standard at the time), and found wide variations in performance and manufacturers overstating light output and efficacy (lumens/watt). The literature of half of the tested LED downlights presented inaccurate information. On average, 70 percent overstated. And many products exhibited performance that was equal to or only marginally better than incandescent, proving the characteristic of being an LED does not qualify it as energy efficient.
Replacement lamps fared the worst. One LED A-lamp promised 80–90 percent energy savings but emitted less than 5 percent of the light output of a typical A17 or A19 incandescent that it was intended to replace.
Fortunately for the LED market, much-needed infrastructure now is being introduced. At press time, the IESNA was in the final stages of publishing LM-79, which will establish a method for performing reproducible measurements of total light output, input watts, efficacy and color quality in LED fixtures and replacement lamps. The IESNA still was formally reviewing LM-80, which addresses lumen depreciation and service life of LED light sources, but the IESNA has not released a concrete publication date.
As manufacturers adopt these standards, electrical professionals will, over time, be able to trust performance claims and compare LED products on an apples-to-apples basis. But these standards do not set efficiency or performance benchmarks. That’s where the Energy Star spec, effective in September 2008, shows its value.
Energy Star is a voluntary labeling program created by the U.S. Environmental Protection Agency (EPA) and the DOE to help consumers identify products that meet minimum efficiency and performance criteria, thereby promoting confidence and acceptance. Products that verify they meet the new Energy Star LED fixtures spec will qualify for Energy Star, a well-recognized and regarded quality brand.
“Energy Star is a valuable mark for helping drive sales toward products that perform well and truly save energy,” McCullough said.
The Energy Star mark will verify that a given fixture provides a minimum efficacy, service life, light output and distribution, color qualities, thermal management, a three-year warranty, and no power draw while off. Initially covered are niche general lighting applications. Products include undercabinet kitchen and shelf-mounted, portable task, recessed downlight (commercial and residential), and outdoor wall-mounted porch, step and pathway fixtures. The Energy Star spec initially does not include other general lighting types or organic LEDs (OLEDs), replacement lamps, or fixtures with a decorative purpose.
The Energy Star spec focuses on luminaire (fixture) efficacy—the amount of light leaving the fixture divided by the input power—not light source efficacy, a departure from how energy efficiency typically is measured. Compact fluorescent fixture (CFL) efficacies are used as the benchmark. For example, to receive the Energy Star mark, an LED commercial recessed downlight would have to exhibit luminaire efficacy >35 lumens/watt—the estimated efficacy of a typical CFL downlight.
Energy Star-labeled LED fixtures, which could be introduced as soon as late 2008, will mean that each product:
“We hear almost daily claims of new performance records being set, and as more time elapses, solid-state lighting technology will begin to make sense for more and more applications. The Energy Star mark is your best assurance that products will perform as advertised, and your customers’ experience will be positive,” McCullough said.
DILOUIE, a lighting industry journalist, analyst and marketing consultant, is principal of ZING Communications. He can be reached at www.zinginc.com.