Estimating the Regression Coefficients in the Formula Relating Solar Radiation to Sunshine Duration and Its Applicability to Indian Locations

Abstract

By assuming a quadratic relationship between elevation (h) and the regression coefficients a and b of Angstrom type correlation, a procedure is suggested for estimating the monthly mean daily global radiation for locations in India. Data from six locations, spread all around India, are analysed to obtain the coefficients of the quadratic equation connecting a and b to elevation of the locations above sea level. The procedure for estimating global radiation is tested by calculating monthly mean daily global radiation values for these six locations. The estimated and reported experimental values agree well and the procedure is accurate for any location in India, with altitude less than 600 m.