Variability in global and direct irradiation series generation: scope and limitations

Carlos M. Fernández-Peruchena (1) , Lourdes Ramírez (1) , Manuel Blanco (1) , Ana Bernardos (1)

1 Department of Solar Thermal Energy [Sevilla]

The synthetic generation of hourly global horizontal irradiation (GHI) series allows the estimation of solar radiation potential by allowing the filling of gaps in records of daily or hourly values. In addition, synthetic generation of GHI can provide an increase of the time resolution of measured (or estimated) GHI series. Unfortunately, since GHI synthetic generation schemes are based on the use of random numbers, they provide different global irradiation values in each generation. Consequently, synthetic GHI series generated from the same set of initial data can exhibit different annual values. This variation is transferred and amplified in the estimation of direct normal irradiation (DNI) through synthetically generated GHI series. In this article, generation of a number of artificial series of hourly GHI and DNI is carried out to investigate and quantify their annual variability. Annual values of GHI and DNI generated series are compared with measured ones provided by the Spanish Agency for Meteorology (AEMET) in Madrid, Murcia, Valladolid and Coruña (Spain). The results of this study indicates that synthetic generation of solar irradiation series must be used as a procedure to obtain hourly-frequency series which presents statistical properties consistent to those observed, not as a procedure to predict precise DNI values.

Mots clés: resource assessment; global irradiation; direct irradiation; synthetic generation; variability

Domaines: Ingénierie de l'environnement

Carlos M. Fernández-Peruchena, Lourdes Ramírez, Manuel Blanco, Ana Bernardos. Variability in global and direct irradiation series generation: scope and limitations. XVI Concentrating Solar Power and Chemical Energy Systems Symposium, Sep 2010, Perpignan, France. pp.041. ⟨hal-00919447⟩