Study of the energy performance of a combined system: Solar thermal collector – Storage tank – Floor heating, for the heating needs of a room in Maghreb climate

Abstract

This paper presents the study of the energy performance of a solar thermal combined system (STCS) composed of: a solar thermal collector; a storage tank with double heat exchangers and a floor heating system to meet the heating needs of a local taken in the Maghreb climate context. The original idea of this study is the consideration of a storage tank with integrated double exchangers allowing on the one hand the accumulation of heat under the action of the exchanger1 connected to the circuit of the collector, to receive the surplus of solar thermal energy during the day and on the other hand to supply it under the action of the exchanger2 as auxiliary heating in the evening to the heating floor. A numerical model of the STCS system was developed under the TRNSYS simulation program. For the validation of the model of the heating floor coupled with the solar thermal collector (DSF), the results obtained by simulation were compared to those from the experiment conducted on a test cell equipped with a heating floor in the climatic conditions of the city of Oran. Other simulations of the STCS system were performed by integrating the storage tank and considering a function regulation strategy, in two stages of the storage tank, between day and night where the efficiency of the tank as a back-up heater was evaluated. The results obtained by simulation show the reliability of the model and the efficiency of the storage tank used as a back-up heater with a coverage rate of 91%. The combined solar thermal system STCS provides energy savings by substituting electric or gas back-up with active solar storage, under the application of an energy management strategy.