An unglazed metallic roof panel solar water heater with a natural circulation

Abstract

The purpose of this research was to design, construct, and test the performance of simple solar water heater. The concept of this work was applied to the metallic roof panel. Widely used in rural of Thailand. To construct this system, seven copper tubes with diameter 12.7 mm were weld to a 1.67 m² metallic roof panel. The volume of storage tank is 90 liters circulated by thermosyohonic force. The experimental results, conducted in February, showed that the system constructed in this study yields maximum water temperature of 53ºC. It should be noted that this system is suitable for domestic hot water system. Additionally, the economical analysis reveled that cost of hot water per liter is 0.03 Baht.