Experimental Evaluation of Solar Water Heater with Trickle Flow using Polymethyl-Methacrylate (PMMA) - Galvalum: Collector Orientation Study

Abstract This study aimed to evaluate the thermal performance of solar water heater system with the trickle flow method using a combination of PMMA (polymethyl-methacrylate) as cover and galvalume as an absorber plate. The flat plate type collector was designed with a closed flow system, where water trickled directly on the surface of the absorber and was recirculated through the storage tank. The experiment was conducted in tropical area in Indonesia with four variations of collector orientation, namely south, north, east, and east tilted at 30°. Furthermore, the parameters measured included solar radiation intensity, wind speed, and water temperature at the inlet, outlet, and in the tank. Collector efficiency was also calculated based on the useful thermal energy absorbed by the plate, while system efficiency was reviewed from the heat energy transferred to the water. The results showed that collector direction had a significant effect on system performance. Collector with east orientation produced the highest total efficiency of 32.7%, with a maximum water temperature of 45.8°C. These results indicate that east orientation is more effective for trickle flow-based solar water heater system in tropical areas. Additionally, PMMA–galvalume material shows potential as a lightweight and efficient alternative for household applications.