When resource grid height is different from tab file, what happens?

[apope0932]

Hey guys,


I have the a wind climate tab file at height of 91m, and I'm intending to create a wind resource grid at height of 84m. WAsP runs without complains but I'm curious about how the process was done.


Does anyone know how exactly WAsP handles the situation when tab file is at different height of the wind resource wind? Any sorts of vertical uncertainty was estimated and reported when the heights are different?


Any thoughts on this topic are appreciated. Thanks.

[elbigkonan]

Hi,

WAsP runs without complaining because what you are doing is exactly what WAsP is meant for, i.e. the prediction of wind resources using measurements which might be at a different location and height.
So if you are estimating a wind resource it means that at least you are doing horizontal extrapolation of the results (in most cases you will do both vertical and horizontal).
In your particular case, all the WAsP models will be used as you first need to estimate a GWC which involves accounting for the topography effects on your tab location. Then you will re-account for topography effects (which will be different as you are at a different location and height) at each of your grid resource nodes and use the GWC to derive the climate/resource. While you do this, WAsP also uses the "background" wind profile, which is used for accounting of the vertical wind shear. So in order to know the uncertainty of all the process you need to know the uncertainty in each of the models of WAsP.

Regards,
WAsP support

[apope0932]

Hey Elbigkonan thanks for the quick turnaround! What exactly is GWC? It feels like you're talking about speed-ups from the context but I'm not hundred-percent sure.


Thanks

[elbigkonan]

GWC: generalized wind climate, i.e. the wind climate where the effects of the topography have been extracted