DOE Testing for LEDs Offers Some Surprises

Aug. 14, 2009
The CALiPER test results for LED lighting products recently published by the Department of Energy (DOE) provide an interesting status check of the state of the fledgling solid-state lighting industry.

The CALiPER test results for LED lighting products recently published by the Department of Energy (DOE) provide an interesting status check of the state of the fledgling solid-state lighting industry.

Some LEDs in the DOE Energy Efficiency & Renewable Energy program’s CALiPER tests outperformed existing light sources like compact fluorescents and incandescent PAR lamps, while an amazing 50 percent didn’t even meet their manufacturers’ published marketing claims.

The fact that the lighting industry needs a performance testing program like its CALiPER testing standards says something about some of the history of product development in the lighting industry. Burned by poor performance of some compact fluorescent lamps (CFLs) and electronic ballasts when they were introduced approximately 15 to 20 years ago, responsible lighting manufacturers want to make sure the first wave of LED products don’t turn off potential customers with poor performance, and are having their products tested under the tough DOE CALiPER testing standards as well as the additional EnergyStar standards.

The CALiPER report said some of the solid-state lighting sources tested in Round 8 — which included replacement lamps, downlights, track lighting, undercabinet fixtures and outdoor fixtures — are “now approaching, matching, and sometimes exceeding the light output levels, distribution, and color quality of similar lamps and luminaires that use traditional sources such as incandescent, halogen, and CFLs. Unfortunately, more than half of the products tested in this round have inaccurate or misleading product literature. Most severely, equivalency claims in product literature for replacement lamps are almost always false and misleading.”

This round of CALiPER testing was particularly interesting because some of the lamps tested are designed to be direct replacements for MR16, PAR and “R” lamps, some of the more common lamps used in the commercial and residential markets. Said the CALiPER report, “Taken as a whole, a wide range of performance is observed among these SSL replacement lamps, with some clearly representing viable replacements for incandescent, halogen, or CFLs and some performing clearly far below manufacturer claims. In general they perform quite well with respect to efficacy, color quality and intensity, but not necessarily so well with respect to total light output, power factors and accuracy of product ratings.”

It was also interesting to note the manufacturers that scored high in this round of testing. Some, like Juno Lighting and Cree and are well-known in the mainstream lighting market; others like Marktech and Lighting Science Group are not yet household names in the lighting business.

An issue related to the performance claims of some manufacturers is the environment in which they test their products. Seminar panelists at the DOE’s Solid-State Lighting Market Introduction Workshop held last month in Chicago, (see EM’s July 17 issue), said some manufacturers make the mistake of not testing their LED lamps in the types of fixtures in which they will be used. Heat buildup in some lighting fixtures not designed for use with LEDs can dramatically shorten the life of the LED light source.

These test results also reflect the fact that LED technology is improving month-by-month and that many if not most of the best-known names in the lighting business are doing their best to develop quality lighting products. But the test results also touch upon the fact that product quality is a huge issue in the LED market and that some new players are rushing into the business with no track record in the market, get-rich quick schemes and little concern for the long-term viability of the products they are now marketing.

Analyzing all of these changes is Jim Brodrick, the DOE’s Solid-State Lighting Program manager. His popular e-mail newsletter, “Postings from Jim Brodrick,” has quickly become a must-read for lighting professionals who want to keep up with the pace of R&D in the solid-state lighting market. In his most recent posting Brodrick said that overall, Round 8 of the CALiPER testing confirmed the continuous upward trend in performance since DOE began the testing program in 2006. But it will take time before LEDs can compete with all conventional light sources.

“Last fall, CALiPER benchmark tested conventional and SSL MR16 lamps from the buyer perspective,” he wrote. “We found wide variations in performance, and the CALiPER MR16 Benchmark Report published in November 2008 concluded that then current MR16s did not meet 20W halogen levels, much less 35W or 50W halogen lamps. Now, just eight months later, the results for SSL MR16 lamps tested in Round 8 are quite encouraging. With respect to color, all have CRI over 70, with the best at 93. All have warm white or neutral white CCT levels, which is fairly similar to the most common halogen replacement lamps. And as for total light output, one of the warm-white SSL MR16 lamps clearly meets and exceeds what a buyer would expect of a 20W Halogen MR16 lamp, and delivers over three times the average efficacy of halogens.”

Brodrick also said some LED replacements for common varieties of floodlights such as PAR20, PAR30 and PAR38 can meet “light output levels and beam characteristics of 35W to 50W incandescent and halogen lamps, with efficacy levels similar to lower wattage CFL products.”

Regarding the accuracy of suppliers’ performance claims, Brodrick said, “Equivalency claims are often solely for the replacement lamp and not for the actual measured performance when integrated into a luminaire. This reflects the learning curve many product integrators face as they begin to better understand how to measure, report and assess LED products.”

One LED manufacturer that exemplifies that potential and challenges that confront LED manufacturers is C.C. Crane Co. Inc., Fortuna, Calif., which markets the GeoBulb as a direct replacement for 60W screw-in incandescent at Priced at $99.95, the bulb is quite expensive, particularly when one considers that a 60W incandescent can be purchased at home centers for less than one dollar.

The GeoBulb also had mixed results in the recent CALiPER tests. It did very well on the tests’ Color Rendering Index (CRI) (a measure of lighting quality) with a score of 80. But its test result for lumens (a measure of how much light reached the intended area or subject to be lit) and lumens per watt (how many lumens are produced compared to how much energy is consumed) were measured by DOE as being under its published claims.

— Jim Lucy