Experimental development of a hybrid solar-gas heating system

The hybrid solar heating systems help in increasing energy savings. However, an optimal configuration along with suitable control strategies will be required to enhance the thermal performance of the system. In the present work, a hybrid solar-gas heating system is built up in Algiers, Algeria, to investigate its thermal performances and thus highlight the annual solar coverage rate. The system consists essentially of two flat plate solar collectors, a gas boiler, and a hot water storage tank. The operation of the installation is controlled by data acquisition card through LabVIEW software. For this purpose, experiment tests have been conducted for different weather conditions on which the hybrid system was operating under three different scenarios simulating working days and weekends. It has been found that temperatures of the storage tank water can reach 36, 34 and 27 °C for days with a global horizontal irradiation of 390, 400 and 533 W/m2, respectively. These preliminary results showed that temperatures of the tank under the steady state operating modes might contribute to the reduction of energy consumption for a given space heating application.