Progress in Thermoelectricity

Of the several processes by which heat is directly transformed to useful electric power thermoelectricity offers unique advantages for several areas of application. The absence of moving parts and the simplicity promise high reliability, silence, and long-lived, maintenance-free operation both as a power source and as a heat pump for refrigeration and temperature control. A substantial effort devoted to materials development has produced new semiconductors with an integrated theoretical efficiency of about 20 per cent. Further progress in materials development is needed to achieve major goals in both military and commercial applications, but important uses can already be visualized. Small power plants for remote areas and auxiliary power supplies for space vehicles are awaiting engineering improvements, some of which again require improved materials for use as electrical contacts and electrical and thermal insulators. Similarly in refrigeration, important military applications and special commercial devices can be produced with existing thermoelectric materials when engineering problems and the auxiliary materials problems are solved.