Solar spectral irradiance measurements relevant to photovoltaic applications

Recently, two spectroradiometers from EKO have been added to the instrumentation available at the ESTER outdoor station of the University of Rome Tor Vergata, with the aim to characterize the spectral irradiance at the site and evaluate its influence on the performances of photovoltaic modules, especially thin films and third generation devices as Dye Sensitized Solar Cells (DSSC). The paper will present the results of more than six months monitoring activity where the spectral solar irradiance in the range 350 nm – 1,700 nm has been measured continuously with a time interval of 10 minutes on a horizontal plane. A wide variety of spectra have been acquired in various weather conditions and first indications about the spectra behaviour on a daily and seasonal basis have been obtained. Moreover also some information about the effect of the weather conditions on the solar radiation spectral distribution will be presented.