Validating an Angular of Incidence Losses Model with Different PV Technologies and Soiling Conditions

Abstract

The purpose of this work is to validate an analytical model for the angle of incidence losses in PV modules, with different current photovoltaic (PV) technologies and soiling degrees. For that purpose it has been developed an outdoor testing facility, with which the electrical characteristics of different current PV modules under direct solar radiation at any incident angle can be measured. The experimental data of the angular losses have been fitted to the analytical model, formerly developed by some of the authors, which describes the angular losses (AL) of PV modules as a function of the angle of incidence of solar radiation. The model also considers the possible existence of soiling on PV modules’ surfaces. As a result, the model has proven to be in good agreement with the data of all the considered PV modules in the case of flat covers. The PV technology has not a significant influence on the angular losses coefficient. The results improve the precision of energy rating models and will contribute to the understanding and quantification of the soiling influence in PV plants. This work is funded by the Spanish national programme Plan Nacional de I+D+i, project CALENER-FV (ENE2009-14333-C03-01).