- DoE Completes Latest Round of Testing of Solid-State Lighting
Anne L. Fischer
As solid-state lighting products begin to arrive on the market, standards-setting organizations, industry groups and the US Department of Energy (DoE) are concerned about standards and test procedures for the new products. The DoE recently changed the name of its Solid-State Lighting Commercial Product Testing Program to the Commercially Available LED Product Evaluation and Reporting Program (CALiPER) and announced the completion in August of a third round of test procedures and product measurements.
Tests were performed on 24 solid-state lighting products with a variety of general-illumination applications, designs and manufacturers represented. Products were sent to independent testing laboratories, where spectroradiometry and goniophotometry were used whenever possible. Surface temperatures were recorded at the hottest accessible spots on each luminaire, and off-state power consumption was measured.
In addition, energy use and light output were tested, with a wide range of performance levels noted, even in products that were designed for the same application and made with the same power level. The LM-79 draft standard for electrical and photometric measurement of solid-state lighting products — which the New York-based Illuminating Engineering Society of North America expected to finalize by the end of 2007 — was used for the tests.
Despite variations, the DoE report concluded that progress has been made since earlier rounds of testing. In the first two rounds, for example, major discrepancies were found between the light output as tested and what the manufacturers claimed it to be. This discrepancy was less apparent in round three, with only a few of the manufacturers overstating performance by 35 to 90 percent.
Data gathered through the CALiPER program will guide DoE planning for solid-state lighting research and development. For example, after the DoE tests a group of products and determines how they are performing, it may discover that a certain heat transfer design is a mistake. According to James Brodrick, solid-state lighting portfolio manager, the department can use that information to put more emphasis on funding that area of research and development. In addition, the data generated by the test program provides benchmarks with respect to other light-source technologies, providing a baseline that can be used for the Energy Star program.
Manufacturers of the tested products receive a report on their own product before the data is published to the project’s Web site (www.netl.doe.gov/ssl/comm_testing.htm). Available on the Web site are three summary reports with no manufacturer names. Full versions of the round-three report can be requested from a link on the site.
The product-testing program is one of the many ways that the DoE is helping to increase availability and use of energy-efficient products. The department also is working on an Energy Star labeling program for solid-state lighting luminaries, is running a design competition for energy-efficient residential light fixtures and is offering a technology procurement process that links products to volume buyers and market influencers.
Although the DoE does not set industry standards, it does work with the seven major standards organizations in a role that Brodrick describes as facilitating collaboration and offering the technical assistance necessary to get standards adopted more quickly.
The department also runs solid-state lighting technology demonstrations, where people in the residential and commercial building industries can tour installations and view selected solid-state lighting products at work. At the same time, measurement data is gathered on energy consumption, light output, color consistency, and interface and control issues so that buyers are provided with up-to-date and reliable data on product performance.
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