Comparative Analysis of Photosynthetically Active Radiation Models Based on Radiometric Attributes in Mainland Spain

The aims of this work are to present an analysis quality solar radiation data and develop several hourly models photosynthetically active (PAR) using combinations radiometric variables such as global horizontal irradiance (GHI), diffuse (DHI), direct normal (DNI) from their dimensionless indices atmospheric clearness index (kt), fraction (kd), (kb) together with elevation angle (?). GHI, DHI, DNI 1-minute frequencies in the period 2016 2021 CEDER-CIEMAT, a northern plateau, PSA-CIEMAT southeast Iberian Peninsula, were used compare two locations very different climates according Köppen—Geiger classification. A total 15 multilinear fitted validated (with independent training validation data) first whole dataset then by kt intervals. In most cases, including showed better performance, among them, that also use variable obtained remarkable results. Additionally, statistical validation, these presented good results when they compared bibliography. Finally, model statistics indicate performance interval than complete models.