Thin-film thermoelectric energy harvesting for security and sensing applications

The past decade has seen significant advances in distributed sensors and sensor networks. Many of these advances have been driven by programs that support national intelligence and security interests. With these advances have come an increased interest in energy harvesting to provide continuous power sources to replace or augment existing power storage systems. 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. This presentation will review the key performance factors and considerations required to optimize each element of the system to achieve the required I-V characteristics for output power.