materials for sustainability & efficiency, thermoelectrics, waste-heat recovery, technology cost
Interest in thermoelectrics for waste-heat recovery has flourished in recent years, but questions about cost and scalability remain unanswered. Prior work investigated the materials, manufacturing, and system costs and thermal and electrical transport factors that govern device efficiency and commercial feasibility. This work applied a power generation cost metric in $/W. The metric enabled an assessment of which materials are most promising for heat recovery. The analysis included thirty thermoelectric materials as well as novel structures such as nanowire, superlattice, and nanostructured bulk. Above 275 °C, many bulk thermoelectric materials can achieve costs below $1/W. The major barrier to economical thermoelectric power generation at higher temperatures results from costs for heat exchangers and ceramic plates. In this work, we apply the cost-performance metric to determine how thermoelectric generators can be designed and implemented for three example waste-heat sources: gas turbines, aluminum smelters, and household water heaters. The results demonstrate thermoelectric waste-heat recovery can be a viable option to improve these energy systems and indicate which thermoelectric materials are most promising for these thermoelectric generators.