Quality Check of Global Horizontal Irradiance Time Series

Integrating PV into power systems is challenged by measurement noise and metadata gaps in irradiance series. A quality control procedure (QCP) is presented, it (i) corrects temporal misalignment between measured Global Horizontal Irradiance (GHI) and clear-sky GHIcs via data-driven time-shift optimization, and (ii) evaluates and cleans kt series with explicit, physics-based thresholds. Applied to 2017-2020 SIAR data, 76/94 stations passed QCP after filtering; for LMOPS (France), a datalogger bug (1-min sampling) was identified and fixed, removing non-physical spikes. The QCP improved CSI mean (−0.9 %) and variance (−4.2 %) in a representative site and produced consistent datasets for forecasting and planning.