Desempenho térmico e eficiência energética em ambiente Hospitalar: estudo da fachada do setor de internação do Hospital do Coração, localizado na cidade de Maceió

Abstract

In Maceió, a city characterized by its wet and hot climate, artificial air conditioning is needed in view of the use and occupancy features of certain indoor spaces. However, this strategy must be combined with efficient energy use and with the possibility of employing passive thermal conditioning strategies. The work herein is aimed at assessing the thermal performance and energy efficiency of the facade of the Hospital do Coração, located in the city of Maceió-AL. Computer simulations were carried out using the Energyplus 8.3 program, starting with the current situation and after alterations to the construction parameters of the facades, in order to evaluate the effect on energy consumption. The results were then compared to those for current thermal and energy performance. Such modifications consisted of adjustments to the ratio of window area on the facade, the installation of a brise-soleil, different windows, changes to the COP (Coefficient of Performance) of the air conditioner and to the external color; ultimately, an analysis of the integrated changes was conducted. The results obtained have shown that the parameters chosen for the computer simulation led to a significant reduction of power consumption of the air conditioner of up to 31% in the case of double pane airfilled windows with a green reflective film, window frame opening ratio of 25%, COP of 3.23 W/W, horizontal brise-soleil, and external white painting. As to thermal performance, the results of the simplified method have demonstrated that the building meets the minimum requirements for thermal performance found in NBR 15.575-4 (2013) when it comes to external walls and to the size of the ventilation opening; yet, the roof has a transmittance greater than what is required by NBR 15.575-5 (2013). Thermal balance of the suite indicated a decrease in the energy necessary to cool the air when carrying out the following simulations: placement of all-around solar protection, painting the roof white, and diminishing the glazed area of the facade to window opening ratio of 25%. Replacing the current single pane glass windows covered with a green reflective film with double pane air-filled windows also covered with a green reflective film led to a similar result, a reduction of just 6.63 kWh/year. The two other types of windows – single pane with no film and double pane air-filled with no film – had a 21% lower performance when compared to the current window. It may be concluded that studies and simple measures can mean significant lowering of power consumption. An architectural project that employs the available means to reduce heat gains by making changes to the exterior will surely help in reducing the power consumption of the artificial air conditioning.