Thermoelectricity for Waste Heat Recovery, Thermal Switching, and Active Cooling

Efficiency in thermoelectric energy conversion is limited by the figure of merit, zT, of available materials and their operating temperature. However, adoption of thermoelectric technology is limited primarily by cost. It is the aim of this work to not only improve zT but describe new ways to integrate thermoelectric materials into practical devices. A composite material based on the commercial standard Bi2Te3 is employed to improve figure of merit by introducing macroscopic pores, where the interfaces are coated with conducting shells. Next, a metal-fin thermoelectric generator is proposed that integrates thermoelectric legs with the heat exchangers. Simulations of convective heat transfer indicate that, in some scenarios, such a generator may be able to produce enough power to replace a conventional alternator. Finally, thermoelectric heat pumping is applied to devices for temperature regulation. Conventional semiconductor materials show promise in thermal switching, where heat is actively regulated, and metals with high thermoelectric power factor provide new opportunities for active heat dissipation.