Hybrid Model for Solar Irradiation Estimation Using Polynomial and Angstr？m-Prescott Equation

The world’s most important energy source, solar energy, is being investigated in a variety of areas under different fields. Especially since the decline of fossil fuel resources, the importance of the solar energy has increased even more. Initial researches on solar energy started in the first quarter of the 20th century and solar irradiation was estimated versus sunshine duration. This study suggests similar procedure to harmonic analysis application to solar irradiation and sunshine duration data. Basis of the methodology is combined application of the POlynomial and classical LINear regression analysis. Therefore, it is referred to PoLin model as a hybrid model. It isolates first the periodicity from the daily values, and then linear regression analysis is applied first to order stationary data. PoLin results are compared with the classical Angstr？m-Prescott, HarLin, and ANFIS models. In the application, solar irradiation site is considered from solar energy potential location in Turkey, namely, at Diyarbak？r. Estimations by PoLin model appears more successful than ANFIS, HarLin and Angstr？m-Prescott approaches