Contribuição termo-energética dos fechamentos transparentes em edifícios comerciais climatizados artificalmente em Santa Maria - RS

Abstract

This paper analyzes the influence of the penetration of solar radiation through the transparent closure in consumption of energy for conditioning of the office buildings in the region of Santa Maria-RS, located in the bioclimatic Brazilian zone 2. To do this, simulations were performed in the computational program Design Builder, in a typical office environment in order to evaluate the comparative results obtained with the use of different types of glass (Solar Factor) by different percentages of area of windows and surface guidelines. The glasses used had solar factor ranging from 0.85, 0.70, 0.56 and 0.29, an opening percentage area of 20%, 50% and 80%, while the solar orientation ranged from 0° to 315° at an interval of 45°. It was observed that for the climate of the city of Santa Maria-RS, considering the daytime use of the building, the consumption of energy for cooling process has higher values compared to the heating and that this difference is directly proportional to the solar factor of the glass and the percentage of openings in the facade. Changes that contribute to a reduction of one of these lead to an increased consumption of the other, these should be analyzed jointly in the process of defining the openings, in order to obtain the lowest annual energy consumption. The simulations indicated higher expenditure of energy with heating on the facades oriented to the south, southeast, and southwest, while the higher cost for cooling occurred on facades oriented to the north, northeast, northwest, regardless of the solar factor or percentages of openings in façade. It was observed that, when established constructive guidelines regarding apertures in construction performance standards for buildings, should be considered together the percentage of area openings, Factor Solar glass and solar orientation of the facade, as the exchanges of heat and entry lighting are naturally associated with these factors in an integrated manner.