Typical Meteorological Year methodologies applied to solar spectral irradiance for PV applications

A Typical Meteorological Year (TMY) is frequently used in solar power for long-term energy yield analysis. Different approaches have been reported focusing on concentrating solar power or photovoltaic power plants that have established different relative contributions of the involved variables (mainly solar irradiance components and temperature) according to the application. For PV applications the estimation of the spectral gains and losses requires of on-site spectral measurements. Long-term analysis of the spectral influence on PV technologies has been performed for over seven years of measured spectral global tilted irradiance in Madrid. The experimental spectra were measured with an EKO spectroradiometer in the wavelength range of 300–1100 nm. The TMY methodology has been used to create a typical spectral year of global tilted irradiance that can be used for computing the spectral factor. This paper shows the different steps in applying the TMY methodology to spectral irradiance and the resulting spectral factors computed for seven different PV technologies. Thus, this approach can effectively be used to characterize the long-term spectral influence of PV technologies in a selected site.