Experimental verification of some clear-sky insolation models

Autor: G. Simonnot, M. Mermier, A. Louche, M. Iqbal
Rok vydání: 1988
Předmět:
Zdroj: Solar Energy. 41:273-279
ISSN: 0038-092X
DOI: 10.1016/0038-092x(88)90145-4
Popis: Clear-sky solar irradiance can be predicted when a number of essential atmospheric parameters are known. A number of parameterization methods to predict solar irradiance with various degrees of difficulty are available in the literature. In this study, three models called model A, model B and model C, with medium degree of difficulty, have been examined. In these models, the solar transmittance due to each atmospheric parameter is available in simple algebraic form. Based on these algebraic equations, the direct normal, diffuse, and global horizontal irradiance can be predicted. These models have been compared with measured data from Carpentras, a French radiometric station. At this station, several daily observations of the clear-sky irradiance are carried out. Corresponding instantaneous values of the Angstrom turbidity coefficient β and several other necessary surface meteorological observations are also made. For diffuse irradiance, a value of 0.95 is assumed for the single-scattering albedo of the aerosols. Based on the calculation of the mean bias error and root mean square error, model C has the best correspondance with the measurements as for as direct irradiance is concerned. Model B appears to be more accurate for prediction of diffuse and global irradiance. Regression equations are provided to help the user of any one of the three models for better prediction of solar irradiance.
Databáze: OpenAIRE