Instrumentation And Evaluation Of Commercial And Homemade Passive Solar Panels

The purpose of this project was to compare water-heating capacities of a commercial passive solar panel and a home designed passive solar panel. The home made solar panel consisted of six, 10 ft long parallel, 1⁄2 in. diameter PVC pipes with two headers and with no insulation. Both panels were placed on the east side roof of the author’s house, therefore they received solar radiation during part of the day. The instrumentation consisted of seven thermocouples and a computer data acquisition system. Two identical, 20-gallon plastic tanks, one tank on each panel, were used for water storage. Two sets of comparative measurements were carried out. For the first set, the PVC solar panel pipes were white; for the second set, the PVC solar panel pipes were painted in black. For the white PVC system the maximum water temperature in the tank was slightly lower than the commercial solar panel tank water temperature. For the painted PVC system, the maximum water temperature in the tank was slightly higher than the commercial solar panel tank water temperature. In conclusion it can be stated that a simple homemade sixpipe, black PVC solar panel is superior to an expensive commercial solar panel. Although water tanks were not insulated, water temperatures in them have reached to about 100 deg-F in September. Such a system may be incorporated into one of the MET courses as a laboratory exercise to demonstrate basic principles of passive solar heating, calculation of heat losses, optimization, manufacturing techniques, creativity, etc.