Comparison of Methodologies to Estimate Direct Normal Irradiation From Daily Values of Global Horizontal Irradiation

Sara Moreno (1) , Silva Manuel (1) , Carlos M. Fernández-Peruchena (2) , Íñigo Pagola (2)

1 AICIA
2 Department of Solar Thermal Energy [Sevilla]

Daily global horizontal and direct normal irradiation (DNI) measured from the database of the Group of Thermodynamics and Renewable Energies (GTER) of the Seville Engineering School are used to compare three different methodologies to obtain daily DNI values from daily global horizontal irradiation measurements. Methodologies are based on combinations of models to generate hourly radiation series as the one developed by Collares Pereira and Rabl [4] or the Time-dependent Autoregressive Gaussian (TAG) model developed by Aguiar and Collares Pereira [5] with daily and hourly global-to-diffuse or global-todirect decomposition models [6] developed by GTER from their own database. The estimated data are classified by the clearness index to analyze the influence of cloudiness on the different methodologies. Furthermore, the hourly decomposition model developed by Erbs is used to study how the use of different decomposition models affects the results.

Mots clés: solar; irradiation; direct; methodologies; TAG; decomposition models

Domaines: Ingénierie de l'environnement

Sara Moreno, Silva Manuel, Carlos M. Fernández-Peruchena, Íñigo Pagola. Comparison of Methodologies to Estimate Direct Normal Irradiation From Daily Values of Global Horizontal Irradiation. 15th SolarPACES Conference, Sep 2009, Berlin, Germany. pp.16136. ⟨hal-00919055⟩