The zenith angle w is given by Eq. (6.72) and depends on the latitude of the
location, the solar declination and solar angle, h, as
cosw ¼ sin/sind þ cos/cosdcosh ¼ sinb
ð6:72Þ
where b is the solar height angle, complementary to the zenith angle.
At 12 h, the solar hour angle h is calculated with Eqs. (6.74), (7.6), and (7.7).
Repeating the above, we get
h ¼ 15ð12 À tÞ
ð 6:74Þ
where t, the apparent solar hour, is given by Eq. (7.6):
t ¼ t uc þ CL þ ET
ð7:6Þ
Fig. 7.8 Diagram of a 3D building (A) and its total shadowed area in horizontal projection (B)
7.11 Example 10: Calculation of the Solar Radiation Intensity Components …
257