Thermogenerators are electronic components that convert heat into electrical energy. They are based on the thermoelectric Peltier effect and the Seebeck effect, named after their discoverers, or use the heat pipe principle. The effects mentioned can be used to convert heat and temperature differences into electrical energy.
The effects have been known since the beginning of the 19th century, but because of their low efficiency they were mainly used in cooling components for electronic components and integrated circuits. Thanks to new compound semiconductors replacing the classic metal alloys, it has been possible to increase the efficiency and use the effects to generate energy from heat. Bismuth telluride and lead telluride are used as composite materials.
Thermogenerators are used in micro energy harvesting( MEH) and are therefore also called energy harvesters. They can be used instead of batteries and provide a self-sufficient power supply for wireless sensors. They generate voltages of a few hundred millivolts (mV), have the advantage of being maintenance-free and are not dependent on battery life.