Study of the Performance of a Thermosiphon Solar Water Heater in the Rainy Season

In this work, we conducted a study of the performance of a solar thermosiphon solar water heater (SWH) during the rainy season. This system is installed in a private home in Ouagadougou, Burkina Faso (12˚19'12.4"N, 001˚27'00.1"W) and has been operating for 10 years. It consists of a flat collector with a surface area of 2 m2, a storage tank with a capacity of 200 liters and two hydraulic circuits (primary and secondary). The collector and the tank are each insulated with 15 cm thick glass wool. The overall objective of this work is to study the influence of the rainy season on the performance of the device. The methodology used is based on the acquisition and analysis of system operating data (temperatures and solar radiation) for 10 consecutive days. Finally, with the data obtained, the SWH efficiency was calculated. The results showed that the performance of the SWH is poor in the rainy season due not only to the variability of solar radiation but also to water infiltration into the collector. Furthermore, the duration of hot water production as well as the final temperatures reached in the tank depend on the intensity and the degree of variability of solar radiation. Finally, the results also showed that the storage tank is well insulated and that nighttime losses are relatively low.