Thermoelectric Generators: Principles, Materials, and Emerging Applications

Thermoelectric generators (TEGs) are solid-state devices that convert thermal energy into electrical power using the Seebeck effect, offering a sustainable solution to mitigate rising energy costs, environmental pollution, and global warming. These generators are advantageous due to their lack of moving parts, silent operation, long lifespan, and compatibility with various substrates such as silicon, ceramics, and polymers. TEGs are categorized based on their design—planar, vertical, and mixed—and can be enhanced through different configurations like conventional, segmented, and cascaded arrangements. The performance of TEGs is often evaluated using the figure of merit (ZT), which considers the Seebeck coefficient, electrical conductivity, and thermal conductivity. Advances in thermoelectric materials, including bismuth telluride (Bi₂Te₃), lead telluride (PbTe), and silver selenide (Ag₂Se), have improved efficiency, making TEGs suitable for a range of applications. In low-power domains, they are utilized in medical devices, wearable technologies, and wireless sensor networks, while in high-power sectors, they contribute to energy recovery in automotive engines, industrial electronics, and aerospace systems. The integration of TEGs into various technologies underscores their potential in energy harvesting and sustainable power generation.