Offshore wind prediction. (2008-11-20)

[Old Forum Archivist]

Hi,

I need to calculate the offshore wind prediction with the sofware WAsP 8.3 and I would like to know what is the methodology to realise this calculation.

Is it the same method that for an onshore calculation?

What parameters are different?

Thank you for your consideration.

Best regards

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It's not a good idea. There are a lot of limits regarding the extension of WAsP calculation offshore (for example, wake decay constant...). I have heard something about GeoWAsP but I think it's not a commercial software...Let's invest 1 million euro for a mast in the sea!

Bye

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In principle, WAsP is adequate for simulating offshore or nearshore wind resources - if the classical 'WAsPological' requirements are met: nearby met. mast in same regional wind climate, etc. etc. There exist several papers on this, try Google "wasp offshore". However, the climatology and topography are often rather complicated near to shorelines, so in such cases the uncertainty may be higher than usual.



If you are estimating the AEP from very large offshore wind farms, the present WAsP wake model may not be adequate; this model was designed for small and medium sized wind farms (by today's standards).



You might want to try to change the WAsP heat flux values for offshore (and onshore) conditions depending on where your site is located. It's difficult to find data for the heat fluxes, but we sometimes consult with the NCEP Reanalysis Electronic Atlas (http://www.cdc.noaa.gov/ncep_reanalysis/) to get an idea of the mean (offset) values. To get the RMS values, one has (unfortunately) to download the data themselves and make the calculation - or make an educated guess.



And, yes, an offshore mast is good to have too.

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