Experimental Investigation of Passive Water Cooling in Solar Heating Thermoelectric Generator

Abstract

In this study, a thermoelectric generator (TEG) system is designed to produce electricity from solar energy. Solar powered two-phase closed thermosiphon (TPCT) type heat pipe is used to heat the hot surface of the TEG, and a 1200 cc capacity passive water-cooled system is designed and manufactured to cool the cold side. The cooling system has two sections as primary and secondary sections which provide a natural water circulation to achieve an efficient cooling. A single TEG is used in most studies in the literature while 5 TEGs are used in this study to obtain a simple, easy and cheap design to generate more electricity. Not only the effect of passive water cooling, but also the effect of using a reflector on the system efficiency is tested experimentally. The system is operated by solar power under three different conditions as non-reflector, semi-reflector and full-reflector. Electrical and thermal data are recorded in a computer and data obtained from 08:00 to 15:00 is used for comparison and calculations. Maximum output power, electrical efficiency and Seebeck coefficient calculations are made for only TEG-1 in which the maximum open-circuit voltage is reached. Results showed that using a heat pipe with a small capacity passive water-cooling, the temperature difference for five TEGs can be reached to generate electricity.