Design and thermal performance optimization of a forced collective solar hot water production system in Morocco for energy saving in residential buildings

Abstract

This paper presents a comprehensive study that aims to assess the energetic performances of a solar hot water collective system under a realistic load consumption profile in Morocco. The case study which has been considered in this work is a residential building located in Fez city. Several parameters are involved into the performance assessment of the collective system. Hence, it was essential to identify the parameters on which we will act in order to carry out the parametric study. In fact, the technology of evacuated tube collectors (ETC) with heat pipes were selected as a fixed study parameter, while a set of other indicators were investigated contributing to the collective hot water system design and optimization, such as the solar collector panel total area, the connecting methods between the collector’s field which could be serial, parallel or mixed connection, the collective hot water storing volume configurations in addition to the intrinsic optical efficiencies of the world’s manufacturers solar collectors. In order to achieve the assessment of the energetic performances of the collective system, four parametric studies were described and carried out to ensure its design and optimization during the dynamic mode operation.The most relevant findings from this research paper are presented as follows. Incrementing the collector’s field area to 120 m2 optimizes the thermal efficiency of the collective system, and the hydraulic booster consumption is reduced. Besides, it would be advantageous to use a total area of 80 m2 to satisfy the hot water need demand over the four seasons, since the overall collective system thermal efficiency remain above 60%. Moreover, is was possible to ensure a seasonal solar fraction which is greater than 50% by connecting a collective storage tank with a volume of 1500 l and a solar collector panel with an area of 100 m2. Last but not least, the effect of the row’s number as well as the number of collectors connected per row on the overall collective system’s solar fraction was also investigated through this study.