Evaluation and thermal analysis of energy production of thermoelectric system using thermosiphon heat pipes and nanoparticle (Al2O3) working fluid

Abstract This study presents the experimental design of a new solar-based thermoelectric generator with heat sinks. The system presented consists of heat pipes, evacuated solar glass tubes, thermoelectric generators (TEGs), and heat sinks. The system utilized five TEGs connected in series on the head of the heat pipe, with five heat sinks integrated into these five TEGs. In the experimental system, pure water and the nanofluid Al 2 O 3 were used as working fluids in the heat pipes. The purpose of this experimentally tested system is to demonstrate that thermoelectric power generation is possible using solar energy. To assess the performance of the proposed generator, measurements of open circuit voltage, wind speed, and temperature at selected locations of the designed system were collected. Based on these measurements, the maximum output power, electrical efficiency, and Seebeck coefficient were subsequently determined. The experimental study was carried out at location 41 $$^\circ$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mmultiscripts> <mml:mrow/> <mml:mrow/> <mml:mo>∘</mml:mo> </mml:mmultiscripts> </mml:math> 14’N—36 $$^\circ$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mmultiscripts> <mml:mrow/> <mml:mrow/> <mml:mo>∘</mml:mo> </mml:mmultiscripts> </mml:math> 26’E on September 6, when weather conditions were suitable. The data collection was performed from 9 a.m. to 2 p.m. The highest open circuit voltage obtained from the systems was 1.41 V, which was achieved in the heat pipe system containing nanofluid Al 2 O 3 in its structure. In addition to the experimental study, the electrical outputs of the TEG system under various operating conditions were also investigated by incorporating numerical and ANN models into the study.