Short- and long-term solar radiation estimation method

Abstract

In this study, Angstrom equation solar radiation estimation values corresponding to the sunshine durations are achieved by a linear equation, which is an improvement over the classical model. The results turn out to be better than the classical Angstrom equation. In the suggested equation, 1–10 days’ solar irradiation values are assumed to affect the present-day values as short-term estimates. The proposed model for summer months (June–July–August) has provided estimations that are in close agreement with observations. Both long- and short-term estimations have been obtained rather successfully. In the proposed methodology there are two extra factors, as dependence coefficients. Finally, the classical Angstrom equation remains as a special case of the model.