Temperature Control for Residential Solar Water Heating Systems

The demand for solar water heating systems has increased significantly throughout the world considering that solar energy is a renewable source able to decrease the reliance on scarce resources. However, the excess of sun radiations (especially during summer) has resulted in an overheating problem which reduces the unit lifespan, causes premature component failure, and reduces the system's performance. This paper presents a design for a temperature control system that can reduce the overheating of residential solar water heating systems, thus protecting the unit. The system accounts for weather conditions as well as household demand. The automated protection method controls most types and models of solar water heating systems, so that it can attain a safe desired temperature without influencing hot water availability. The developed prototype was tested on a full-scale solar water heater with promising results.