Influence of Glazed Façades on Energy Consumption for Air Conditioning of Office Buildings in Brazilian Climates

The energy performance of buildings is defined by their electrical systems and thermal exchanges through the envelope, mainly by glazing systems. This study evaluates, through computer simulation, the influence of glazing façades in the energy consumption of the air conditioning system of an office building in five Brazilian cities with different climate conditions. A computer model was developed to analyze the influence of windowto-wall ratio, type of glass and façade configuration in the energy need for air conditioning. The results show that the energy performance of the building is highly influenced by the configurations of the façade, mainly by glazed elements. In cold climates, high thermal transmittance of the envelope helps the dissipation of internal heat gains, reducing energy consumption for air conditioning. In this case, the use of insulated glass unit can be unhelpful. Furthermore, the opening area causes energy consumption variation up to 27.5% depending on climate and type of glass. But the use of a high selective glazing system can decrease the energy need for cooling when the window area is increased