High Temperature Thermoelectric Materials for Waste Heat Regeneration

Motivated by non-renewable petroleum consumption and the perceived climate change due to carbon dioxide CO2 and other greenhouse gases, effort has been focused on recuperating lost energy from hot exhaust gases. Automobiles using thermoelectric generators TEGs are possible solutions due to the potential for high regenerative rates associated with the amount of waste heat and the corresponding high temperature. TEGs are solid-state heat engines that contain no moving parts, and are compact, silent, and extremely scalable. This brief review covers basic thermoelectric material principles, discusses the performance of several candidate thermoelectric materials, and concludes with reliability concerns exacerbated by the high temperatures associated with automotive exhaust.