Determination And Analysis Of Total Solar Spectral Radiation Falling On Horizontal Surface

The knowledge of the amount of total solar spectral irradiance (TSSI) falling on horizontal surface is essential requirements for designing solar energy systems, especially for photovoltaic system. The main purpose of this paper is to study and analyze the total spectral irradiance in Baghdad (Lat.33º ٢١ N 44º ١٤ ◌َ E Long . and 34m above MSL). Measurements were made by Epply spectral pyranometer using Schott filters WG7, OG1, RG2 and RG8 with the wavelength intervals [(280-2800), (530-2800),(630-2800) and (695-2800)]nm, respectively. The study include the monthly average of the hour, and daily solar spectral irradiance and the correlation between the solar altitude and sunshine duration with different solar spectral irradiance