SSL and Energy Star

On June 2, EPA released a revised Energy Star (TM) requirement for residential light fixtures, with immediate effectivity. This standard allows LEDs to be used in residential light fixtures with an Energy Star label. Great right?

Well, not so fast. DOE has been working with the Solid State Lighting (SSL) community since 2000 to advance the SSL industry. In the process, legislation was passed authorizing DOE to work with an industry group, the Next Generation Lighting Initiative Association (NGLIA), to develop programs to assist SSL technology development and deployment. From this collaboration have come programs that ensure better measurements of the light quality 'on task', funding for developments of technology, workshops and conferences on the issues associated with integrating this technology into the existing value chain for lighting, etc. DOE also developed, in long concert with the industry, an Energy Star Criteria, released in September 2007 for effectivity in September 2008. Note, this was developed over the course of a couple of years, was intended to promote real energy savings, and built on the standards and test methods developed with industry. In contrast, the EPA "technical ammendment" was developed in relative secrecy with little outside input and uses unproven test methods.

So why is this important? In the 1980s the first compact flourescent bulbs hit the market. Unfortunately, these products suffered from a variety of problems which we all probably remember. The colors were often too harsh, some complained of flicker, light generated by the devices was often less bright or less useful that similarly-rated incandescent bulbs, etc. These problems had the effect of slowing down the adoption of CFL bulbs, increasing energy consumption, and slowing the change of the industry. In the end, if the product doesn't provide satisfactory results to consumers, it will not be adopted.

Energy Star (TM) is not only an efficiency label, but also a de-facto quality label. Products carrying this rating are assumed by consumers to at a minimum meet the expectations for performance of traditional products. However, in the case of LEDs, there are significant issues related to the nature of the light generated in order to make that light useful. If you were to take an emitter (light engine) and test its light output vs. energy input, you could have an erroneous representation of the actual useful light generated. This is because light emits from the top of the chip, and from the sides, and the radiation pattern may not be well used by the fixture into which the light engine is installed.

Unfortunately, the EPA only chose to measure the efficiency of the light engine. DOE's CALIBER program which performs calibrated measurements of LED lighting products has shown repeatably that this is insufficient for determining useful light and thus useful efficiency. If you had to replace a fixture with two LED fixtures to get the same amount of light, it would halve the efficiency. Furthermore, other characteristics of the light have not been considered or are very loosely specified. For instance, 'color temperature' or the apparent color of the white light is acceptable up to a rating of 6500 deg-K. This is a very harsh bluish color, familiar if you have one of those early LED flashlights, and, per the CFL experience, totally unacceptable to consumers. By comparison the warm yellowish light of a 100W bulb is about 2800 deg-K.

By contrast, DOE's Energy Star criteria include a wide variety of quality metrics including actual light on tast, acceptable color temperature ranges, and efficiency metrics that improve over time. This last is especially important because LEDs are getting better every year, and fixture design is improving rapidly as well. While the standards are more explicit, they are not onerous, and should serve to provide at least a minimum qulaity level to product bearing the Energy Star label. Furthermore, with the one-year run-up to the standard release, manufacturers have time to bring their products into compliance and have them tested at a certified lab.

So why is EPA doing this? It isn't clear, but one problem with the Energy Star program all along has been the dual ownership of the program between EPA and DOE. DOE would seem to be the better stakeholder since its interest are in energy conservation, even though the pollution impact is also important. This could be, then, a classic 'turf war' between the two departments. Ultimately, programs mean money and power for a Department.

The Solid State Lighting Industry Trade Association (SSLITA), under the auspices of the Optoelectronics Industry Development Association (OIDA) filed a grievance with the EPA Office fo Inspector General, claiming that the duplication of effort side-stepped protocol and wasted government resources.