Passively Cooled BiTe Thermoelectric Generator for Operation in Harsh Environments

Energy harvesting from waste heat is becoming more prevalent as energy conservation efforts continue to increase worldwide. thermoelectric generators (TEGs) are devices that can harvest such waste heat and convert it into useful electrical power. Traditionally, active cooling methods are used to maximize the thermal gradient across a TEG module in order to optimize the energy conversion process. However, active cooling is impractical for a significant number of industrial harsh-environment applications. To examine the feasibility of using passively cooled TEG devices for producing useful electrical power, a bismuth telluride (BiTe) TEG device was fabricated and tested from 200°C to 290°C on the hot side, without active cooling on the cold side. As such, the temperature difference across the TEG device remained consistent at approximately 50°C over the range of hot-side temperatures tested. Under these conditions, the BiTe TEG device produced a single-couple average voltage of 8 mV over the range of test temperatures, and single-couple powers up to 0.10 mW at 290°C, despite the lack of active cooling. These results show the capability of TEG module integration to power electrical circuits for high-temperature harsh-environment applications operating under passive cooling.