Natural Comfort

a comparison of the original tool with the adaptation to the INI-C

Abstract

To estimate the fraction of hours occupied in heat discomfort in naturally ventilated commercial buildings, Rackes, Melo and Lamberts developed and made available the Natural Comfort interface developed in Python 2.7.  This interface was later adopted and adapted in the form of a web interface for the new Inmetro Normative Instruction for the Energy Efficiency Classification of Commercial, Service and Public Buildings, INI-C, published in 2021. The present work aims to compare the two tools, as well as to evaluate their results through a case study using Block 3 of the Complex of the School of Engineering of UFMG. The analysis allowed the observation of the limits of application of the tool, as well as to propose ways of adapting characteristics of the buildings in order to enable the analysis by the tools, which are considered to be simpler to use than the thermo energetic simulations. The results showed differences of up to 81% in FHdesc when different climate files were considered. Finally, the results between the original interface and the adapted interface were significantly different in most cases, with addition and decrease of the Fraction of Hours Surplus by Heat, FHdesc, obtained. These differences between methods reached up to 200% for the interfaces as function of the parameter analyzed. Sometimes the results presented values lower than 10% and indicating, therefore, the non-need to install an air conditioning system according to the parameters of the INI-C. However, in most cases, the installation of this system would be necessary.