Cost-effective waste heat recovery using thermoelectric systems

Optimizing thermoelectric (TE) materials and modules are important factors, which can lead to widespread adoption of waste heat recovery systems. The analytic co-optimization of the TE leg, heat sink, and the load resistance shows that all parameters entering the figure-of-merit (Z) do not have the same impact on cost/performance trade-off. Thermal conductivity of the TE material plays a more important role than the power factor. This study also explores the impact of heat losses and the required contact resistances. Finally, we present the theoretical cost performance ($/W) of TE waste heat recovery systems for vehicle waste heat recovery application, assuming hot side gas temperature of 600 °C and a cooling water temperature of 60 °C.