Statistical analysis of solar radiation data

Solar radiation is the most important parameter in the design and study of solar energy conversion devices. In this study, statistical methods were used to analyze the solar radiation data for the city of Konya in the Mediterranean region of Turkey. Experimental data were obtained from the State Meteorological Station in Konya over a 9 year period from 1990 to 1998. The empirical coefficients a and b of the modified Angstrom-type regression equation were determined, while the values of the monthly average-daily clearness index (K-T) were calculated. A nonlinear model was also developed between the monthly average daily global radiation (H) and ambient temperature. The values of the monthly average-daily hours of bright sunshine (S) varied between 9.41 and 14.58. The values of K-T ranged from 0.54 to 0.60, averaged for the period studied. It may be concluded that the present model estimates the values of H for Konya reasonably well.