Measurements and models to evaluate diffuse solar irradiation over tilted surfaces in spain

摘要

This paper shows a comparative assessment of tilted diffuse solar irradiation models using hourly horizontal diffuse solar irradiation measurements. Detailed measurements on inclined and horizontal surfaces are carried out at the C.I.B.A. Laboratory of Valladolid (Spain) and are unique in the Castile and Leon region. Ten sky diffuse models are used to estimate diffuse irradiation on tilted surfaces. Root mean square and mean bias errors are used to determine the performance of each tilted diffuse model and a comparison among the results has been made. From the results it can be seen that Reindl and Perez's models are better than the others and they are both recommended for predicting diffuse solar irradiation on tilted surfaces.