Experimental Investigation of a Parabolic Solar Trough Collector with Titanium-Coated Receiver to Heat Water in a Tank for Domestic Uses

This study aims to examine the performance of a parabolic solar trough collector (PSTC) for the efficient use of green renewable solar energy. The study investigates the energy taken by water (ETW), receiver efficiency (RE), cumulative heat gain (CHG) by water in the tank, receiver terminal temperature difference (RTTD), and percentage of electric energy saving (PEES) at various mass flow rates (MFR) with and without coating of the receiver. The study found that the PSTC performed best with a coating (WC) of the receiver at a mass flow rate of 18.72 kg/h compared to the case without coating (WOC). At the mass flow rate of 18.72 kg/h, significant increases in ETW, RE, CHG of water in the tank, and RTTD were observed for the case WC compared to WOC, at 25.88, 25.87, 23.96, and 20.56%, respectively. Meanwhile, the maximum PEES of 66.8% was observed at the MFR of 18.72 kg/h for the case WC. There is a 23.45% reduction in the annual cost per kWh of energy used for the case with coating compared to the case without coating. In addition, a substantial amount of CO₂, equivalent to 3,121.03 kg, can be offset by using the PSTC to heat water over its entire useful life. Pure titanium powder was used as the coating material.