61. Statistical Analysis of Short-Term Solar Radiation Data over Aligarh (India)

This study aims at exploring solar radiation in the Aligarh region of India (latitude, 27.88°N; longitude, 78.08°E), due to the fact that measured solar radiation data for this region is scarce. A new set of regression coefficients for the Angström-type correlation for estimation of monthly average daily solar radiation on horizontal surfaces in Aligarh (India) has been presented. The regression coefficients were applied to the data of bright sunshine hours obtained from the Solar Energy Laboratory, Department of Mechanical Engineering, Aligarh Muslim University, during the period of September 2013 to February 2014. The results were compared with the correlations of other researchers available in literature and solar radiation data obtained from measurements. Correlation for the estimation of monthly average diffuse solar radiation is also developed in terms of the ratio of diffuse to global radiation. The performances of the proposed correlations were analyzed by mean bias error and root mean square error. A good agreement was found between the estimated and measured values following the application of the new proposed correlations. Thus, monthly average global, diffuse, and direct solar radiation on a horizontal surface in the Aligarh region of India has been obtained.