Testing SSL Products for Energy Star Qualification: LSI Explains DOE Requirements

The DOE has issued Manufacturer Guidelines for qualifying both interior and exterior lighting products for the coveted Energy Star label. Very significantly, the program focuses on lighting quality as opposed to simple lumen output. Marketable light quality in Energy Star for SSL is now defined by the photometric distribution, color characteristics, and efficacy of the lighting fixture.

The reason for this focus on lighting quality is that a successful application of a lighting product will meet consumer’s expectations not just for lumen output, but for safety and comfort factors as well. For example, outdoor pole-mounted luminaires require certain intensity values (candlepower) in specific angular zones to provide the desired light patterns on the pavement. Similarly, indoor downlights require a certain percentage of lumens to be emitted in a specified angular range, so that the application is both useful and comfortable to the consumer.

Procedurally, the DOE’s 2008 definition of light quality means to lighting product manufacturers that SSL products must be tested in both an Integrating Sphere and on a Moving Mirror Goniophotometer. The requirement that SSL fixtures be tested on a goniophotometer for intensity distribution represents an informed change in the DOE’s view on lighting products, which stems from its CALiPER program results.

An additional shift in test procedures must occur to test SSL products accurately, because the LED in an SSL fixture cannot be conveniently removed for testing it in a bare state. Since testing cannot be based on manufacturer’s ratings of standard test lamps, relative testing procedures are inapplicable for SSL. Please see CEO Ian Lewin Ph.D.’s article in LEDs Magazine, “Absolute Photometry has Relative Benefits for LED and SSL Performance Evaluation” of August 2008, for more information on the subject of absolute photometry for SSL.

At just ten days, LSI’s CALiPER-approved testing laboratories offer one of the fastest turn-around times in the industry. Please contact Vice President Ryder Tunney (rtunney@lightingsciences.com or 480.991.9260, ext. 305) if you have further questions regarding Energy Star for SSL.