Using broad-band irradiance data to model the short circuit response of aSi modules

aSi modules show large variations in their response to the incoming irradiance as measured by broad-band irradiance sensors, making the check and prediction of their performance difficult when only broad-band data are available. One approach to overcome this difficulty is given by the use of detailed models to estimate the irradiance spectra from the broad-band data. Here, it is tested to what degree the detailed modeling could be substituted by a semi-empirical approach to reflect the modules response based on but the information on direct and diffuse irradiance and solar geometry. The model performance is measured by its capability to give the correct monthly mean short-circuit current together with a reasonable R² value of the scatter of modeled and measured data. A first test of a respective model has shown reasonable results.