Thermoelectricity for Energy Harvesting

Abstract

Thermoelectricity (TE) is the conversion of heat into electricity (Seebeck effect), or of electricity into heat or refrigeration (Peltier effect). The use of the Seebeck effect could allow heat to be saved which would be otherwise lost. Although the conversion efficiency is very low, it has been enjoying renewed favour for several years, and novel research and development leads have been investigated, such as new materials and the structuring of matter at the nanoscale. This combination has led to active investigations worldwide, but without achieving the decisive breakthrough, which will give TE a prominent place among energy harvesting technologies. The most promising applications of TE, in the context of energy saving, concern thermal engine heat recovery (particularly in transport applications), and human body heat scavenging to power portable devices. TE for energy harvesting has several barriers to overcome: low conversion ef‐ ficiency; toxicity; and low availability of chemical elements constituting part of the most inter‐ esting thermoelectric materials. In this context, the main challenges for nanotechnology are to demonstrate high efficiency improvement, and to display low cost implementation in thermoe‐ lectric materials