An Empirical Study on the Thermal Performance and Dynamic Behavior of Wall Integrated Thermosiphon Solar Water Heater

Abstract

In this study, the evaluation of the dynamic behavior and thermal performance of the “Façade integrated Natural circulation Solar Water Heating System” installed in the residential house was carried out. Experimental tests were performed during the all year around in the rural houses of 166 m2 in size. Facade integrated solar collector of 5 m2 were installed on the south-facing. Electrical heater of 1 kW capacity as an auxiliary heater was installed at the upper part of the heat storage tank. The analyzing results are as follows. (1) Monthly average solar fraction was 51 to 87% and yearly average value is 64%. (2) Hot water supply temperature in December which has the lowest solar altitude is 37 to 76℃. The highest working fluid temperature of solar collector in this period was below 84℃. The temperature difference of working fluid between the collector inlet and outlet has been shown to be around 9 to 26℃. (3) Overheating which is one of the biggest problems during summer did not appear at all, but rather had hot water supply temperature is rather low as 30~47℃ in summer than winter, which is supplied by a small solar load. The solar collecting temperature has been shown to maintain below 55℃. (5) The thermal performance of Facade integrated solar collector can be increase due to the reduction of heat loss to the back of the collector wall integration of the collector is reduced. As a conclusion, Facade integrated natural circulation type Solar Water Heating System is a well-functioning without any pumps or controllers, and it was found that the disadvantages of conventional solar water heaters, hot water or hot water system can be greatly improved.