The greenhouse effect is becoming more serious, affected by the release of exhaust gas of internal combustion engine vehicles. The waste thermal energy from the exhaust gases seems to have no use but it can be used for other purposes. The thermal energy can be converted into potential difference when there is a temperature difference between two conductors of different conductivity, explained by Seebeck’s effect. The presence of a heat sinkHeat sink is important to avoid thermal throttling while harvesting the heat energy released. In this study, a heat sinkHeat sink for the application of thermal energy harvestingEnergy harvesting using a thermoelectric generatorThermoelectric generator (TEG) is investigated. The material selected for the heat sinkHeat sink was aluminium. The heat sinkHeat sink and TEG model were developed using the ANSYS Fluent software. The temperature profile was collected from the energy source to the TEG module until the end of the heat sinkHeat sink. Different profiles of heat sinkHeat sink, circular and rectangular finsRectangular fin were employed to investigate the effect of fin shape on the temperature profile. From the analysis, it was found that the circular finCircular fin heat sinkHeat sink produced the highest temperature difference compared to the rectangular finRectangular fin and flat fin heat sinkHeat sink.