Development of a Design Tool for Sizing and Optimizing Thermosyphon Solar Water Heater Systems: A Case Study for Tripoli-Libya

Thermosyphon solar water heaters can be considered the most popular solar technology for supplying households with the needed hot water for domestic purposes. However, sizing these systems is mainly based on experience and trial methods, these methods were established more on intuition instead of scientific approaches. This paper is aimed at studying the sizing of thermosyphon systems through the development of a dedicated generic design tool. The tool can be utilized by manufacturers and engineers to arrive at optimized systems designed according to the operating and weather conditions of certain geographical locations. The design tool is implemented in this study to find the optimum system design that fits households in Libya (as a case study in this work) and accounts for the weather conditions of Tripoli and a simple, but representative, hot water load pattern. Two different sizes of thermosyphon systems covers hot water load of 180 lit and 240 lit, and two different configurations with vertical and horizontal tanks are studied and the best fit designs are obtained. The design tool has shown a great potential, and with further development and validation would be capable of widespread commercial application.