Nvestigation of the lifecyclye of buildings used for different purposes in terms of energy and exergy analysis

The main goal of the present study is to analyze of the ratio of the exergy to the energy consumption (REXE) during the lifecycle of the four different buildings used for various purposes comparatively. This ratio, which is used for better understanding of the lifecycle of buildings, is utilized in this study as a new thermodynamic parameter to evaluate the energy efficiency of the building lifecycle. The building lifecycle parameter, named as REXELC, gives an opinion regarding the energy consumption of buildings during their lifecycle. It is also used as a simplified way of calculating exergy consumption during building lifecycle. In addition, the cost, energy and exergy consumption per construction area of the selected buildings are employed as variables in the REXELC analysis. REXELC is mainly calculated considering REXE values for five different stages of building lifecycle. These are as follows: building materials' production, building maintenance, building construction, building demolition, and building running. As a result of economic analysis, it is concluded that buildings having too large or too small REXELC values are not economical. Moreover, four different regression models are utilized in order to determine the relationship between REXELC and the energy consumption of the building lifecycle. The best results were obtained in quadratic and power-2 models, thereby; the selected buildings were evaluated in four regions. Finally, REXELC values would be a substantial instruction in optimizing of the building envelope design.