Spectroradiometer comparison under outdoor direct normal irradiance and indoor highpower AM0-like conditions

Intercomparisons of primary instruments are of paramount importance to guarantee reproducibility and equivalence of calibration and are expressly required for laboratories applying the quality scheme outlined in IEC/ISO 17025 standard. The correct and reliable measurement of the spectral content of the used light source(s) is one of the main tasks in the process of a generic photovoltaic (PV) device calibration; this requirement has become more and more important since the technology biodiversity has increased in the PV world. The two afore mentioned issues were among the main driving forces to establish a network of European and International PV laboratories and industries willing to share good practices in spectroradiometric calibration and measurements, and to periodically check their equivalence-of-result in measuring the spectral content of the sun or of solar simulators. This paper will report on the preliminary results from a spectroradiometers intercomparison performed measuring solar direct normal incidence spectral irradiance and global normal incidence spectral irradiance under an indoor high-power AM0-like source.