10106785PV system Degradation Assessment using Statistical MetrologyClosedCollaborative R&DInnovate UKThis project is a collaboration between Statkraft and the National Physical Laboratory (NPL). It aims to develop a methodology to measure accurately the photovoltaic (PV) power degradation rate within a large-scale solar PV power plant. Degradation rate is a core parameter for solar project's financial models, which are used to forecast long-term revenues, perform project valuation, etc. This key rate represents the yearly loss in capability of generating energy. In summary, it is how much your power installed capacity degrades per year. Historically, industry bases its rate on research institute papers and manufacturer rates. However, such rates are based on previous iterations of technologies and different operating conditions, leading to considerable uncertainty in the actual rate. Measuring degradation rates on operational solar PV power plants is not a trivial task. There are multiple uncertainty factors involved. In academic research, degradation rates are measured in a device-per-device basis, which is not commercially feasible at scale. In industry, a common alternative is to use long-term datasets (\>5 years) of the PV system performance collected at system or inverter (subsystem) level. However, such an approach can be problematic, as data may not be properly curated throughout time, causing significant amount of data to be filtered out, reducing the sample representativeness. PV systems also operate in an uncontrolled environment. It is a challenge to disentangle genuine degradation from variable weather and seasonal effects. This project presents a unique intersection of Metrology and Statistics challenge. On successful completion, it will provide commercial means of accurately assessing the power degradation of solar PV power plants.