Solid-State Lighting: An Opportunity for Nanotechnologists to Address the Energy Challenge
| Category | Online Presentations |
|---|---|
| Abstract | More than one-fifth of the electrical power consumed in the U.S. is used for general illumination. Much of this energy is wasted to heat filaments in incandescent lamps, a century-old technology with an efficiency of about 5%. Fluorescent lighting is more efficient, but problems of color quality, temperature sensitivity and the toxicity of mercury present problems in disposal and consumer acceptance. Rapid advances in light emitting diode (LED) technology promise to offer a solid-state alternative with superior lifetime, efficiency and color quality. The U.S. Department of Energy has set a goal for 2025 to develop a solid-state lamp that is more efficient, longer lasting and cost competitive compared to conventional technologies, targeting a system efficiency of 50% and the color quality of sunlight. Success will bring the potential for reducing the energy consumed for general illumination in the U.S. by 33% in 2025, equivalent to avoiding the construction of 41 1000 MW power plants (Navigant Consulting, 2003). In this tutorial, I will define the common metrics used to evaluate lamp performance, including luminous efficacy, color temperature, and color rendering index. The principal features of a hypothetical device that would meet the DOE goals will be outlined and compared with today's R&D approaches, including blue (In,Ga,Al)N LEDs combined with partially absorbing yellow phosphors, uv (Ga,Al)N LEDs exciting multiple phosphors, and organic LEDs. Finally, I will highlight several approaches to achieving the ultimate solid-state white lamp, including strain-engineered nanostructures, nanoplasmonics, dislocation filtering, and transitioning to alternative low-cost substrates. |
| Bio | Dr. Sands received his Ph.D. in Materials Science at the University of California, Berkeley in 1984. Following nine years as a Member of Technical Staff and as a research group Director with Bell Communications Research, Inc. (Bellcore) in Red Bank, NJ, Sands joined the faculty at the University of California, Berkeley in the Department of Materials Science and Engineering. In 2002, he became the Basil S. Turner Professor of Engineering at Purdue University in West Lafayette, IN, with a joint appointment in the Schools of Materials Engineering and Electrical & Computer Engineering. Sands has published over 200 papers and has been granted 12 patents in the areas of metal/semiconductor contacts, heteroepitaxy, thermo-electric materials, ferroelectric and piezoelectric materials and devices, semiconductor nanostructures, laser processing and heterogeneous integration. His present research efforts are directed toward the development of novel nanocomposite materials for applications in solid-state lighting, direct conversion of heat to electrical power, and thermoelectric refrigeration. In November of 2006, Sands became Director of the Birck Nanotechnology Center in Purdue’s Discovery Park. |
| Sponsored by | NCN@Purdue Student Leadership Team |
| Cite this work | Researchers should cite this work as follows: |
| Time | 02:00 PM, April 04, 2007 |
| Location | EE Building, Room 317 |
| Tags |