Weather Data Sources for Performance Modeling

Obtaining high quality weather and irradiance data for performance modeling studies is one of the most important steps in PV performance modeling, since the uncertainty in the irradiance data usually accounts a large amount of the total uncertainty.  The modeler usually starts with historical data that has been compiled especially for solar applications (e.g., NSRDB, TMY).  However, when the results of the model are being used for large investment decisions, additional data is usually used (e.g., satellite data and site specific ground measurements).