Spectral irradiance effects on the outdoor performance of photovoltaic modules

The outdoor performance of photovoltaic modules is influenced by spectrum. Even if the irradiance level and the operating temperature is the same, performance difference of photovoltaic modules between the seasons can be increase up to 15% depending on the photovoltaic module type. In this paper, seasonal spectral irradiance effects on the outdoor photovoltaic module performance and previous studies has been summarised thoroughly. The spectrum indicators which are used for spectra characteristics, Useful Fraction and Average Photon Energy are described in detail. This study also indicates spectrum effects on PV performance and outlines the present studies investigating this effect.