Residential lighting market needs its own Energy Star criteria

Nov. 5, 2008
Alex Baker, EPA’s Lighting Program Manager for Energy Star, discusses some of the issues surrounding the addition of LEDs to the EPA’s Residential Lighting Fixture program.
[Background: On June 2, 2008, EPA announced a technical amendment to its Energy Star Residential Light Fixtures specification (RLF version 4.2) to enable LED light engines to be used in this type of fixture. The Department of Energy (DOE) has also developed Energy Star criteria for solid-state lighting (SSL V1.0), which became effective on September 30, 2008.]

Residential/decorative is a special case

The SSL V1.0 specification [the Energy Star specification introduced by the Department of Energy] is fully appropriate for commercial, industrial and architectural lighting because it employs fixture photometric data that these manufacturers already gather in the normal course of doing business.

However, the residential segment of the market has never conducted full fixture photometry; this type of testing is inappropriate and overly burdensome for decorative residential fixture manufacturers, who operate within much tighter cost constraints than those in the commercial segment (recall in San Diego my comparison of the $200+ commercial downlight to the $10 residential downlight).

For residential fixtures, data resulting from these tests is of dubious value; for instance, would luminous intensity distribution data for a Tiffany style fixture assist a consumer with a purchasing decision?

Performance thresholds

The RLF V4.2 specification is equally as stringent as the SSL V1.0 specification; in fact, it was a stated goal of the SSL program to require performance rivaling that of the long-standing Residential Light Fixture (RLF) program. Since its inception in 1997 the approach of Energy Star’s oldest lighting program has been to evaluate the photometric performance and efficacy of the fixture source (and other fixture-related criteria).

This approach - comparing measured source performance against performance thresholds applicable to all technologies - ensures that Energy Star qualified residential light fixtures provide 75% energy savings over incandescent products, without sacrificing quality or lifetime, and also enables consumers to make apples-to-apples product comparisons. EPA so far has held two comment periods regarding the V4.2 amendment (our latest closed on October 20), and remains open to further industry input and discussion.

Test procedures for LED light engines

Working with the American Lighting Association and the National Electrical Manufacturers Association, the program has maintained a database of lamps and ballasts which exceed the program’s minimum performance thresholds. The simplicity of using these off-the-shelf components to earn the Energy Star is what has kept residential fixture manufacturers engaged with the program for the past eleven years, resulting in nearly 16,000 fixtures currently qualified.

The LED light engine is a natural extension to the program's source-based testing philosophy, represents the type of off-the-shelf solution that residential fixture manufacturers are seeking, and is the approach that some RLF Partners and LED solution providers have already embraced.

The ASSIST Recommends test procedure referenced in RLF V4.2 was developed by LED manufacturers, and is currently under review for IESNA standardization, similar to the development of LM-79 or LM-80. EPA, working with the Lighting Research Center (LRC), has trained several labs to perform the testing procedure; a list of labs is available upon request.

EPA is confident in the strength of this testing procedure, and working with the LRC has tested several of the most promising fixture designs from our Partners. To date, we have found no fixtures capable of meeting the long-established 50 lumens per watt efficacy requirement (one of many requirements of the specification, which also includes stringent color requirements).

Future developments

Confusion about the two specifications is generally clarified by reviewing the scope and specification for the Residential Light Fixture program, available for download on the Energy Star website. Version 4.2 represents years of refinements to the specification, borrowing from lessons learned working with consumers and retailers, and from mistakes made with early CFL products.

Going forward, EPA will be monitoring which fixtures qualify under each program and will have a robust stakeholder process for further improvements to the specification once there are useful experiences to reference. EPA anticipates meeting with DOE in the near future to clarify larger programmatic issues.