Wind values: Are they computed?

[tecnun]

Hello,

I m about to upgrade my older version to the current 6.39. So far I am introducing hourly values of these 3 meteo variables: Irradiance global, irradiance difusse, temperature. The fact is that when i simulate the project, in order to compute an accurate temperature loss result, i have a tool (based on experience) to set conductivity numbers depending on each case. Now, if I am not wrong, the model computes wind speed!. We expect, for instance, fewer losses when the climate is very windy am i right? but i go further...now if the model computes that, how can i make use of the conductivity number, when the modules are free, roof mounted (with more or less backsheet air conduction etc)? Any help would be very useful

Thanks Best Regards

[André Mermoud]

The model doesn't "compute" wind speed of course, but it can use wind speed data if present in the meteo data.

This is taken into accout through the parameter Uv in the Heat transfer parameters ("Detailed losses > Thermal parameters").

Now the Wind velocity values may be read in hourly values in your imported data when available (including from Meteonorm).

If they are specified only in monthly values, PVsyst is not able to generate synthetic hourly values (we don't know any model for that). In this case de specified monthly values (averages) will be used during the simulation.

But sorry, we don't have really reliable values to propose for the Uv parameter.