Influence of shading devices on incident solar radiation on horizontal indoor surfaces in Brasília

Abstract

This article estimates the influence of different solar protection systems on incident solar radiation in horizontal internal surface of computational models representing residential spaces in Brasília. Both insufficient and excessive exposure to solar radiation can pose risks to building occupants, ranging from acute and severe respiratory illnesses to thermal discomfort and a consequent reduction in energy efficiency. Eight different azimuths (N, NE, E, SE, S, SW, W, NW) and five shading scenarios were considered: (1) no solar shading, (2) alpha shading/eave 50 cm, (3) alpha shading/fins 10 cm, (4) beta shading on both right and left sides 50 cm, and (5) beta shading/fins 10 cm. The analysis aimed to identify the influence of these scenarios on the area of incident solar radiation (Wh average annual daily), including its maximum and minimum ranges, and the reduction of peak radiation levels. The results indicate that horizontal shading elements (alpha types) are the most effective in reducing incident thermal load (up to 50% reduction) and in increasing the area exposed to solar radiation (up to 45 times greater) compared to the no-shading scenario.