Thermoelectricity is the technical discipline concerned with the conversion of heat into electrical energy. One important area within thermoelectricity is the recovery of waste heat from technical systems such as engines, power plants, industrial facilities, and motor vehicles—as well as from environmental heat sources, in applications such as energy harvesting. Similar to other forms of alternative energy, thermoelectricity has the potential to contribute meaningfully to power generation from waste heat and ambient temperature differentials.
The science of thermoelectricity is based on two key effects discovered in the 19th century: the Seebeck effect and the Peltier effect. These two effects are closely related and often occur simultaneously, but they can be harnessed independently. In both cases, a temperature difference can generate an electrical voltage—or, conversely, an applied voltage can produce heating or cooling.