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The present work aimed to examine the performance of a thermoelectric generator (TEG) augmented with a hydronic evacuated tube solar collector heat exchanger used to heat a cold zone. TEGs were operated on the temperature difference between hot water circulated through the heat exchanger and the cold temperature of the surrounding space. The setup model of a heat exchanger with TEGs installed on the outer surface was examined numerically under steady state conditions for natural and forced convection modes. The results obtained show that 1.03 W of electricity could be produced when the temperature differences across the TEG and air velocity are 60 °C and 0.5 m/s, respectively. Also, an increase of 17.47% of TEG power was achieved for each 5 °C drop in surrounding space temperature and by 11% for each 5 °C rise in circulated hot water temperature. Besides the importance of improving TEG efficiencies, the amount of generated electricity may be valuable when large-surface area heat exchanger units are installed in large systems.

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In this article, a single stage ammonia-water absorption refrigeration cycle integrated with thermoelectric power generators driven by evacuated tube solar collectors is presented and investigated. The working fluid is ammonia-water solution, and the hybrid system was modeled, and analyzed using EES software. The system coefficient of performance (COP) was found to increase with increasing the generator temperature. From the results obtained, when the cycle operated with 0.99 ammonia mass fraction, it was found that the best location of the thermoelectric generators is at the rectifier between the generator and the condenser where the value of COP exceeds 0.82 at temperature difference across the TEG of 60℃. The other locations, between condenser-evaporator and evaporator-absorber, show similar performance.