Thermal energy harvesting system is an electronic power generation system based on thermoelectric sensor technology. Thermoelectric sensor technology is usually applicable for harvesting smaller amounts waste heat in the order of micro watts to a few watts. Thermal energy harvesting using micro-scale thermoelectric generators is a promising approach to alleviate the power supply challenge in ultra low power systems. In thermal energy harvesting systems, energy is extracted from the thermoelectric sensor transducer using an interface circuitry, which plays a key role in the determining the energy extraction efficiency.

Thermoelectric Sensors & Thermoelectric Power Conversion System

Thermoelectric sensors are also used for micro-scale power generation based on the principle that they can sense heat energy and output an equivalent electric current. The use of waste heat is an attractive source of energy for many applications where μW-mW power is required. The implementation of a thermoelectric power conversion system requires several basic elements in addition to an assumed heat source. These elements are: 1) a thermoelectric device, 2) a heat sink, 3) voltage regulation, 4) an energy storage device and 5) load management. The design and optimization of the system (and each element within the system) is highly dependent on the thermal boundary conditions and the power load.

Applications of Thermoelectric Energy Harvesting Systems

  • Vehicle Waste Heat Energy Harvesting: At least two-thirds of the energy in gasoline used in cars and trucks is wasted as heat. Thermoelectric energy harvesting semiconductor materials can convert waste heat into electricity, could capture this waste heat, reducing the fuel needs of the vehicle and improving fuel economy by at least 5 percent. But the low efficiency and high cost of existing thermoelectric materials has kept such devices from becoming practical in vehicles.
  • PCB Motherboard Thermal Energy Harvesting: Thermoelectric Microconverters are used for energy microgeneration through energy harvesting by taking advantage of temperature differences that are converted into electrical energy using the Seebeck effect. Thermoelectric Microconverters are attached to high heat releasing components on printed circuit boards (PCB) such as microprocessor, power-supply ICs.
  • Human Body Heat Energy Harvesting: Micro-scale thermoelectric generators with thermoelectric energy harvesting interface circuit are used to extract electrical energy from human body heat, for powering batteryless self-powered portable healthcare monitoring devices.
  • Self-Powered Batteryless Wireless Sensor Network: Micro-scale thermoelectric generators are used to harvest the ambient thermal energy in the air, to power the batteryless wireless sensor networks.