Consider a building in Dammam. Calculate the total solar radiation incident on a south facing, vertical surface at solar noon on June 21st. givens : Latitude = 26,4 Reflectivity of the ground = 0.6 Assume the sky to be cloudless. Helps to answer: Find the following : Latitude angle (I), Hour angle (h), Declination (d), altitude angle (B), Tilt angle (2), surface (wall) azimuth angle (), solar azimuth angle (y), solar azimuth angle (a) Then calculate the direct, diffuse and reflected radiation intensities.