Combined Efficiency Calculation of Bismuth Telluride and Lead Telluride in Thermoelectric Module

Abstract

The heat rejected from an internal combustion engine is dumped into the atmosphere as waste heat. If this waste heat energy is tapped and converted into usable energy, the overall efficiency of an engine can be improved. The percentage of energy rejected to the environment through exhaust gas is approximately 30-40%.The thermoelectric generators are used for power generation . Thermoelectric modules which are used in thermoelectric generators are solid state devices that are used to convert thermal energy from a temperature gradient to electrical energy and it works on basic principle of Seebeck effect. The objective of this project is to include fin effect to increase cooling rate , to reduce the temperature by increasing the temperature difference and to use long fin and avoid accumulation of heat in between fins . The TEG system is directly connected to the exhaust pipe and the amount of electricity generated by the thermoelectric material is directly proportional to their heated area . The materials used in TEG are Bi2Te3 - Bismuth Telluride and PbTe - Lead Telluride . Bi2Te3 module TEG is highly efficient in room temperature , but heat withstanding capacity of Bi2Te3 is less than PbTe.The combination of these thermoelectric materials are used for better efficiency . The testing is done for above conditions and experimental results with this setup are performed and presented. 

Keywords: thermoelectric generator, bismuth telluride, lead telluride, Seebeck effect, waste heat recovery, thermoelectric module, internal combustion engine, thermoelectric materials, fuel efficiency, energy conversion, thermal energy, power generation, figure of merit, nanostructured materials, exhaust systems, heat exchanger, semiconductor alloys, energy efficiency, harmful emissions