- Meteonorm Timeseries
Sonnendach (Swiss solar cadastre) shows higher radiation values than Meteonorm. The reason for this are different data sources and time periods.
The new Swiss solar cadastre www.sonnendach.ch of the Swiss Federal Office of Energy (solar potential analysis by Meteotest) delivers especially in the region between Geneva and Zurich (midland) higher global radiation values than Meteonorm.
The reason for this are different data sources
On one hand the period 2004-2014 shows 4-5% higher radiation values than the older period, on the other hand the satellite data overestimate the radiation by 2-3%. The combination of both lead to differences of up to 5-10% for the Swiss midland.
See also documentation: Publications Sonnendach.ch