Case 2. Fixed Horizontal Shade

In the second case study, we consider a fixed shade that is installed to block radiation during the cooling season in Milan, i.e. June 1st to September 15th. We would like the dimension of the shading to be so that it would start blocking radiation from 10:00 am June 1st when the 5 years median of incident radiation on the surface is 360 W/m2. In this case, we are eliminating direct and diffuse solar radiation when the solar altitude reaches 49 degrees, however, we will keep the reflected radiation from the ground. Fig. 8 displays the incident radiation on the wall when the horizontal shading is deployed. It is observed that the designed shading cannot adequately block the radiation, as we have values higher than 500 W/m2. This is due to the fact that in September the solar elevation is low; however, the incident radiation can reach as high as 500 W/m2. Therefore, we decreased the threshold of solar altitude to 38, where it can block the direct solar radiation for approximately 99% of the time during the cooling season (Fig. 9).