DOE provides update on Solid State Lighting program
The Fourth International Conference on Solid State Lighting, held in the first week of August 2004, opened with an update from Jim Brodrick of the US Department of Energy (DOE) on the Solid State Lighting program, which is seeking to improve the performance of both LED and OLED technologies for lighting applications.
The goal of the program is "By 2015, to develop advanced solid-state lighting technologies that compared with conventional lighting technologies are much more energy efficient, longer lasting and cost competitive, by targeting a product system efficient of over 50% with lighting that accurately reproduces sunlight spectrum."
DOE has also appointed the Next Generation Lighting Industry Alliance (NGLIA) to act as its industrial partner and to assist with planning and agenda-setting.
The purpose of the DOE program is to benefit from the energy savings that potentially could be achieved by replacing current lighting sources such as incandescent and fluorescent lamps with LED-based lighting. Figure 1 compares current lighting technologies.
A recent study suggested that solid-state lighting could reduce energy consumption for lighting in the US by around 30% by 2025, saving more than $125 billon in consumer electric bills (link). These figures represent the predicted level of progress with an investment of $100 million per year, which the DOE is still hoping to secure from Congress, but at present around $6-7 million is directed annually to the solid-state lighting program.
Brodrick outlined some of the successes of the program, including a project involving Lumileds and Sandia that has achieved quantum efficiencies of 76% using quantum dots for downconversion in white LEDs (see Innovative materials, processes, and tools improve performance, quality of white LEDs).
DOE has also funded work at Cree Lighting to improve LED packaging efficiency and brightness through the development of new structures and materials, resulting in a white LED demonstrator with an efficacy of 74 lm/W.
This is an extract from a longer article originally published in the October 2004 issue of Compound Semiconductor magazine.