1.    Potential for inferior product quality compared to other illumination alternatives if sufficient scientific breakthroughs are delayed;

2.    Bulky and heavy product designs due to SSL heat sink requirements;

3.    Uncertain product lifetime, insufficient warranties, and lack of expedited testing procedures;

4.    Costly product design and engineering, including choice of rare earths, wafer, and substrate design; and

5.    Costly packaging and components and product manufacturing.

For uniform and consistent adoption of SSL, improvements need to occur upstream quickly to ensure that the market is not tainted early with inferior products and that SSL products continue to come down the cost curve.

Research and Development

Several upstream R&D needs must be addressed if widespread adoption is to occur. For example, LED R&D support is needed for improving the yield, efficiency, and operation at high power and high temperatures. One specific development, discussed in Chapter 3, is the development of low-cost, highquality substrates for GaN for the growth of lattice-matched LED structures. The removal of such defects as would occur due to lattice mismatch in LEDs should increase reliability, yield, and efficiency. Improving LED light output and color is also important because most LED lamps currently available do not have the same light output and color rendering properties as incandescent lamps, and those that do have lower efficacies.

New dimming switches (“dimmers”) will need to be developed. As is the case with some CFLs, existing dimmers used with incandescent luminaires may not work with LED replacement lamps because of perceptible flicker, no smooth dimming, radio interference, and insufficient loading (dimmers require a minimum load). Even though LED lamps are labeled “dimmable” they are not universally dimmable by the myriad of dimming systems currently available. Consumers accustomed to incandescent dimming might notice and be bothered by the fact that LED lights do not get warmer in color as they dim.

LED lamp heat management needs to be improved. Even though heat management requirements are much less for LEDs than for incandescent lighting, both the point heat source nature of LEDs and the thermal sensitivity of the device create a thermal management challenge. If LEDs and OLEDs are to compete with fluorescent lamps and other light forms, particularly in the commercial sector, efficacy must be improved. And because many applications require an omni-directional lamp, the unidirectional emission from the LED must be modified by lamp design to become more omni-directional.


Midstream market activities, as defined for the SSL industry and depicted in Figure 6.1, include all of the means and processes for moving products from R&D and smaller-scale manufacturing to full-scale manufacturing and, ultimately, to architects, engineers, lighting designers, contractors, and retailers for sale to and use by consumers. This definition is broader than what might typically be defined as midstream because of the heavy emphasis in the SSL industry value chain on continued R&D and smaller-scale manufacturing, which in this case is included as an upstream activity. Midstream activities are also defined to include product labeling for consumer information and for marketing and advertising, which includes ENERGY STAR® and related labeling systems, such as the Northeast Energy Efficiency Partnership’s DesignLights™ Consortium, established outside of the federal government.

Midstream market actors principally include distributors, designers, and contractors responsible for designing and installing lighting in commercial and industrial buildings, and lighting contractors and electricians serving the residential sector. Midstream labeling efforts help facilitate and inform decision-making by these market actors. The barriers and challenges to widespread adoption in residential, commercial, and industrial sectors, while generally similar, can also be quite different. The lighting systems design and product decision makers are different for each sector, and decision makers in each sector have a different level of knowledge and experience with SSL technology. Bringing information to all lighting decision makers uniformly and consistently through ENERGY STAR® or other labeling programs has proved valuable in deploying new lighting technologies, whether for CFLs in recent years or SSL today. Examples highlighting the success and value of labeling programs are discussed below and later in this chapter.

General midstream barriers include, but are not limited to, the following:

1.    Risks associated with moving from demonstrations and niche market product manufacturing to full-scale standardized product manufacturing;

2.    Availability of SSL products on the market in retail and other outlets with still uncertain product demand;

3.    Lack of availability of some SSL products and light forms (not a full array of lighting solutions yet available);

4.    Lack of awareness of applications and benefits of SSL by architects, design engineers, building professionals, and consumers; and

5.    Lack of information and training of wholesalers and retailers on various SSL light forms, product applications, performance, and costs, which impede stocking decisions, product placements, and sales emphasis.

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