STTR Phase I: Sustainable Thermo-electric Conversion of Waste Heat

This Small Business Technology Transfer Phase I project will demonstrate and evaluate a novel film-based proof-of-concept Thermoelectric Energy Conversion (TEC) device. This research will advance the energy landscape through an innovative technology with a superior combination of efficiency, power density, and cost. TEC devices represent a zero emissions and zero operating cost technology. About 60-70 quadrillion British thermal units (BTUs) of domestic heat energy are wasted per year. Harvesting even 20% of this waste heat will supply as much power as 10-20 new nuclear power plants. By scavenging waste heat from residential and industrial sectors (such as chemicals, manufacturing, oil and gas, refrigeration, transportation, and power plants), the technology will have a resounding impact on the energy sector and the economy. Finally, this effort will expand the current TEC market of $350 million to encompass a much greater share of the total $4 billion energy harvesting market. Compared to traditional thermoelectric devices, the proposed design produces orders of magnitude higher temperature differentials utilizing micron-scale films, with a highly scalable manufacturing process. This is a transformative shift from the current design practice with bulk (millimeter-scale) materials. Even with inferior values of ZT (0.15, compared to the bulk figures of 0.5-1.0), the proposed design yields 9.8% efficiency at 200 degrees C, triple that of conventional designs. At 600 degrees C (the temperature of typical engine exhausts), the efficiency (28%) becomes viable and the power-to-weight performance is superior to competing devices. Unlike conventional TEC devices, no forced cooling of the cold end is needed to maintain the temperature differential. The most promising aspect is that this innovation will replace today's serial and laborious manufacturing process with a scalable and high-throughput method. This will increase power density and lower product cost in a similar fashion as has occurred in the semiconductor industry.