Clear Sky file generation

From the Knowm format weather import, you have the possibility to generate a full year *.MET file of clear sky conditions.

The clear sky model mainly describes the absorption of the atmosphere without any clouds. This file should not be used for a system yield yearly evaluation of course ! But it could be useful for example:

• For some sizing checks of a system behavior during full sunny conditions,

The clear sky model is only based on the location coordinates (Latitude, Longitude, Altitude). However it may be slightly modulated by an atmospheric trouble index, named the Linke Turbidity Coefficient, describing the water vapor contents and the aerosols. This coefficient may vary from 2.0 (very dry and clean sky) to 5 or 6 (humid and/or polluted conditions). The default value of 3.5 is well representative of most of the sites.

The Linke coefficient is present in geographical sites created with data from Meteonorm 9.0.