The internal combustion engine used in majority of cars at the present time do not use their fuel input
very efficiently. A majority of this energy is dissipated as heat in the exhaust. The related problems of
global warming and dwindling fossil fuel supplies has led to improving the efficiency of the internal
combustion engine being a priority. One method to improve the efficiency is to develop methods to
utilise heat in car exhausts that is usually wasted. Two promising technologies that were found to be
useful for this purpose were thermoelectric cells (TECs) and heat pipes. Therefore this project involved
making a bench type, proof of concept model of power production by thermoelectric cells using heat
pipes and hot engine exhaust gases. 8 cells were used and managed to produce 6.03 W when charging
the battery. The system operated with a heat to electricity conversion efficiency of 1.43%. The discrepancy
between the actual efficiency and the predicted efficiency of 2.31% is most likely due to the cells not
operating at their optimum voltage. The predicted efficiency is approximately 1/9 of the Carnot efficiency
and the actual efficiency is approximately 1/15 of the Carnot efficiency.
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