Here is the abstract you requested from the Thermal_2011 technical program page. This is the original abstract submitted by the author. Any changes to the technical content of the final manuscript published by IMAPS or the presentation that is given during the event is done by the author, not IMAPS.
|Concentrated Solar Thermoelectric Co-Generation Systems|
|Keywords: solar, thermoelectric, cogeneration|
|In an endeavor to harness and convert a fraction of the sun's heat radiation into useful energy, we present our experimental studies on concentrated solar thermoelectric and hot water co-generation systems. The main idea of our studies is to extract unused waste heat energy from a power generator while maintaining an effective temperature difference across the generator. The studied systems utilize optics to concentrate solar radiation onto the top surface of a thermoelectric (TE) device used for power generation. We use two off-the-shelf Fresnel lenses with varying concentration ratios of 86X and 32X and a commercial TE power generator consisting of series-connected elements of p-type and n-type bismuth telluride alloys between two ceramic plates. The surface of the TE exposed to solar radiation, called the hot side, is painted black to maximize the absorption of incoming heat energy at infrared (IR) range wave length. The studied systems also employ a heat exchanger unit which uses a flowing supply of water to draw out unused heat energy from the opposite surface of the TE called the cold side. This heated water is then stored into a hot reservoir, which is useful for residential houses and small buildings. We use an off-the-shelf water flowing CPU cooler as the heat exchanger, the water flow rate of which determines the temperature of the TE's cold side. High thermal conductive silicone paste is applied between the TE module and the CPU cooler to minimize the contact heat dissipation. Figure 1 shows the concept of design and the final construction of the studied systems. It can be seen a Fresnel lens focuses solar radiation onto the hot side of the TE while a supply of water flows though a CPU cooler receiving heat from the cold side of the TE. The temperature gradient produced across the TE is converted into useful thermoelectric power measured across an optimal load resistor.|
|Vernon K. Wong, Student
University of California, Santa Cruz
Mountain View, CA