TY - JOUR
TI - Fenestration peak solar heat gain: A review of the cloudless day condition as conservative hypothesis
AU - Fontana Lucia
AU - Quintino Alessandro
JN - Thermal Science
PY - 2011
VL - 15
IS - 1
SP - 223
EP - 234
PT - Article
AB - Peak solar heat gain through fenestration, particularly for clear and cloudy  day conditions, was estimated, using an approach based on the ASHRAE  methodology and considering the correlation between hourly clearness index kT  and diffuse ratio of the total radiation. Hourly SHGCLEAR and SHGCLOUDY  values for surfaces facing the basic cardinal orientations and the horizontal  surface, at different latitudes, on the 21st day of each month, have been  computed and compared. Results show that in many cases solar heat gain for  cloudy day may exceed that for clear day. For wall exposures near the North  the clear day condition could not be the most conservative condition for the  peak SHG evaluation.