How to create WRG Files and Wind Mast (.tab) files

Hi,

I have a domain set up which I can load all my shape files into openwind. I now face the task of populating it with a wind resource grid and mast data. My question is how can I create a WRG and TAB file, that will load into open wind? I don't have acess to WAsP, but I do know the wind resource and mast data at given lat and lon. So I have the data but I require the know how to implement it. Do you have a short script or any ideas

thanks

Luke

Hi Luke,

I am still debugging the new windflow model in openWind but once that is ready and released you will be able to do everything that you describe in openWind. In the meantime, you could keep yourself out of mischief by finding some terrain elevation data and ground cover data for your site as you'll need these to run the windflow

Also, you'll need to get your wind data into WAsP TAB file format (hint: check out the Risoe site for a handy free app).

I intend to release something in the coming two weeks (i.e. before EWEC 2009 in Marseilles).

Cheers,

Nick

Great, I have managed to create WAsP Tab files form my mast data, I also have some terrain and ground cover data. I am now stuck on the point wrg file. I look forward to the new release

Thanks

You don't need point WRG files to use the windmap. Point WRGs are used with WAsP to represent the TAB file. The WindMap in openWind does not use Weibulls as it is a map of mean wind speeds by direction and so there is no need to use point WRGs. We simply compare the mean wind speeds in the TAB files to the mean wind speeds in the wind map. This means that we avoid the errors associated with weibull curve fitting. I presume that the reasoning behind the Garrad Hassan method of comparing the weibull values in the point WRG with the weibull values in the site WRG is that the weibull curve fitting errors will tend to cancel each other.

Anyway, in short you're good to go.

See my posting on how to create wind maps.

Nick

Hi Nick,

Openwind seems like a great piece of software.  I am still trying to get to grips with it though.  I have met mast data and shapefiles etc but I am stuck at creating a TAB file so I can use the windflow part of the program.  You mention above a smll executable that will translate my mast data to a tab file being on the Risoe website but unfortunately it looks like they have incorporated that feature into the latest edition of WASP so the program is gone.  Can you help?  This is the last piece of the puzzle  I need so I can use openwind.

Thanks

Steve

Previously nick wrote:

You don't need point WRG files to use the windmap. Point WRGs are used with WAsP to represent the TAB file. The WindMap in openWind does not use Weibulls as it is a map of mean wind speeds by direction and so there is no need to use point WRGs. We simply compare the mean wind speeds in the TAB files to the mean wind speeds in the wind map. This means that we avoid the errors associated with weibull curve fitting. I presume that the reasoning behind the Garrad Hassan method of comparing the weibull values in the point WRG with the weibull values in the site WRG is that the weibull curve fitting errors will tend to cancel each other.

Anyway, in short you're good to go.

See my posting on how to create wind maps.

Nick