ABSTRACT
Energy consumption has been rapidly growing with the increase in the worldwide human population and technological development. There is an urgent need for a higher magnitude of energy production to meet industrial needs while considering the global crisis. Currently, most of the required electrical energy is produced from fossil fuels at the cost of enormous waste heat and carbonaceous gas emissions. For eco-friendly and sustainable advancements, there is significant emphasis on finding alternative sources of renewable and clean energies. One of the solutions for converting waste heat into electricity is using thermoelectric phenomenon. Since the discovery of the Seebeck effect about two centuries ago, the fundamental physics for understanding the transport mechanisms, materials modeling, characterizations, and device designs have progressed, resulting in the demonstration of practical thermoelectric generators.
In this chapter, we describe thermal energy harvesting and thermal management methods based on thermoelectric, thermomagnetic, and thermal diode phenomena. Initially, the constructive approach and recent advancements in the design of thermoelectric materials and devices are reviewed. Detailed discussion is provided on understanding thermoelectric materials, mechanisms involved in controlling transport properties, and strategies utilized to improve the thermoelectric performance, and an overview of the characterization techniques of thermoelectric properties is explained. Further, we describe the design of a thermoelectric device using finite-element-based modeling. The challenges in identifying high-performance thermoelectric materials and potential solutions are mentioned. A discussion on correlations between the computational modeling and experimental results in terms of obtained output power from the thermoelectric generator is provided. We also discuss the advancements made in the design and development of thermal diodes and thermomagnetic generators. These topics are included to provide exposure to various alternative approaches being developed to further expand the impact of solid-state thermal energy conversion approaches.
