Development of Low-Cost Solar Water Heater Using Recycled Solid Waste for Domestic Hot Water Supply

Faculty of Mechanical Engineering, Universiti Teknikal Malaysia Melaka, Malaysia

Abstract

This research is focused on the development of a low-cost solar water heater (SWH) system by utilizing solid waste material as part of system elements. Available technologies of the solar water heater systems, heat collectors and its components were reviewed and the best system combinations for low cost design were chosen. The passive-thermosiphon system have been chosen due to its simplicity and independency on external power as well as conventional pump. For the heat collector, flat plate type was identified as the most suitable collector for low cost design and suits with Malaysia climate. Detail study on the flat plate collector components found that the heat absorber is the main component that can significantly reduce the solar collector price if it is replaced with recycled solid waste material. Review on common solid wastes concluded that crushed glass is a non-metal material that has potential to either enhance or become the main heat absorber in solar collector. A collector prototype were then designed and fabricated based on crashed glass heat collector media. Thermal performance test were conducted for three configurations where configuration A (black painted aluminum absorber) used as benchmark, configuration B (crushed glass added partially) that use glass for improvement, and lastly configuration C (black colored crushed glass) that use colored glass as main absorber. Result for configuration B have shown a negative effect where the maximum collector efficiency is 26.8% lower than configuration A. Nevertheless, configuration C which use black crushed glass as main heat absorber shown a comparable maximum efficiency which is at 82.5% of the maximum efficiency for configuration A and furthermore have shown quite impressive increment of efficiency at the end of the experiment. Hence, black colored crushed glass is said to have quite a good potential as the heat absorber material and therefore turn out to be a new contender to other non-metal heat absorber such as plastic and rubber.