STTR Phase I: Post-Peltier Thermoelectrics for Power Generation

This Small Business Technology Transfer (STTR) Phase I project will develop a new class of heat engines that can be used for electrical generation. These heat engines, which are based on thin films of pyroelectric materials, perform all the functions of conventional thermoelectrics, but are not constrained by the competition between thermal and electrical conductivity that has hampered the development of high-efficiency Peltier devices. These "post-Peltier thermoelectrics" or thin-film pyroelectric generators have the potential to improve the efficiency and lower the costs for harvesting electrical power from waste heat. The flexible, low-weight and durable thin-film format opens many new opportunities for exploiting a wide range of heat sources from sunlight to automobile engines. Additionally, similar devices can be used for energy efficient refrigeration and cooling. A thin-film pyroelectric generator has a layer of pyroelectric material sandwiched between two thin-film heat switches. The thin-film heat switches are an essential, new technology that is a major focus of this Phase I program. Switches with high-thermal-conductivity contrasts would enable thin-film pyroelectric generators to outperform conventional technologies that rely on the Peltier effect or on vapor compression.
The broader impact/commercial potential of this project is that its success would launch an entirely new approach to energy harvesting. While many technology sectors benefit from advanced materials and the use of information processing, progress in thermal management and the exploitation of waste heat lags far behind. Today's cooling devices, for example, largely rely on decades-old vapor compression systems or Peltier thermoelectric devices. Thin-film pyroelectric electrical generation is a new approach to heat engines that has the potential to far outperform conventional Peltier devices while capturing their advantages, such as being compact and having no moving parts. The thin-film format of these "post-Peltier thermoelectrics" allows low-cost manufacturing and engenders countless new applications that would be impossible with conventional devices. Ultimately, this technology could create substantial new industries, well-paying jobs, and huge economic and environmental savings. Carmakers could incorporate thin-film energy scavenging devices into automobile radiators, generating enough power to increase the overall efficiency by more than 5% and reducing our dependence on foreign oil by 100 million barrels each year. Electric power plants could extract extra electrical energy from hot wastewater, increasing total power production by about 1% and cutting our annual carbon emissions by 800 million tons.