Duncan

Hi Bruno, I'm a bit confused by what you mean when you say a "roughness class of 3.1-3.2" can you explain?

Hello, Sorry to disappoint you but no, WAsP 10 does not let you get any data *from* Google Earth. GE is used only as an alternative way of displaying spatial data from your projects. Google Earth has an internal elevation map (I think these are grid data from the Shuttle, but I'm not sure). WAsP can't read those data, and even if it could, the format would be wrong.

Of course, I would very much like to rectify this bug. We have never heard of it before, so we need to reproduce it. Do you notice the same with other workspaces or projects? If not, then could you please send me your workspace so that I can try to reproduce the problem?

http://www.wasp.dk/Support/FAQ/SRTM.html (Remove the terminating full stop.)

Try this: http://www.wasp.dk/Support/FAQ/SRTM.htm

I think I understand now. Note that the WRG RSF formats are export formats from WAsP, and are not useful internally. The idea is that if you want to use the WAsP results in WindFarmer or OpenWind (or some legacy application which depends on those formats), then you can dump some part of the grid results out to file and take it from there. There's no way to open a WRG/RSF in WAsP 10 again. If someone wants to share a grid with you, then they should probably send you the workspace file, or maybe the project. But that advice doesn't help your situation, because someone has sent you a bunch of WRG files and you want to examine the data which they contain. Each WRG actually contains about 40 interesting grid maps, I think (elevation; all-sector a, k, P/AEP; sectorwise a,k,f ). Which do you need? The format is simple and well-documented. Could you write a script or simple program to extract what you need from them?

In the last couple of days, the British OS has made a lot of map data freely available for download under an initiative called OpenData, see (http://www.ordnancesurvey.co.uk/oswebsite/opendata/index.html) The licencing seems very open and reasonable (http://www.ordnancesurvey.co.uk/oswebsite/opendata/licence/docs/licence.pdf. I just downloaded the whole Land-Form Panorama data set (10m elevation contours) in DXF format, and was able to load it to the WAsP Map Editor with no problem.

I should add that you need a WAsP 10 licence for this application to work.

WAsP is a single-threaded application which can use only one processor core. For a few years, we've been getting occasional disappointed emails from users who find that their brand-new multiple-processor PC doesn't speed up the WAsP calculations. We have usually advised them to split the grid into several different workspaces and launch several instances of WAsP, which is not much fun. In some future version of WAsP, we'll address this problem directly. Meanwhile, we decided to put together a little utility program which would do this split/calculate/recombine procedure automatically. The working name for this program is GridWhizz. It seems to be working fairly well. Now we'd like to invite some users to help us with testing. Any volunteers? We'll take the first dozen or so people who express an interest. Post a reply here, or email me.

Hi HPJ, Sorry not to have replied before. If I understand right what you want to achieve, then the most elegant solution is probably to use site groups under the wind farm. Each site group can have a different WTG (in this case WTG/Performance Table selection). Then you can move the turbine sites in and out of the different groups between calculations. Does that help? Or does it just leave you wondering how to move the sites around in a script? Duncan.

No, sorry, I don't think that we have a script like that. What kind of output would you prefer? Excel? Word, HTML?

Hello, sorry you haven't received a proper answer to this yet. I wonder if this paper offers any help? http://www.wasp.dk/Support/DownloadFiles/GiebelGryning-ShearAndStabInHighMetMastsAndWAsP_Delft2004.pdf

WAsP takes the histograms as input and then fits Weibull distributions to them. For a predicted wind climate, Weibull distribtions are all you get. So there's nothing in WAsP which will give you a predicted wind histogram: you haven't missed a hidden feature! If you need to generate a histogram to match the Weibull PDF, then doing it in Excel seems like a smart move. But it sounds as though you need to tweak your algorithm slightly to handle speed bins of 1 m/s. Can you post the algorithm here? Maybe someone can suggest a change that will give you what you need. Is this a common requirement? Are other people doing this as post-processing to WAsP calculations? Maybe we could hack up a script for that.

Sorry. That's not supported. But why would you want to re-open the same precalculated data in another project? It would be immediately invalidated: you would need to recalculate it anyway.

WAsP does not ship with data, other than a few simple examples. There are some notes here http://www.wasp.dk/Support/FAQ.html A possible source of map data is http://dataforwind.com/. You could also contact your national mapping agency. There's some software called GlobalMapper which might be useful in finding, converting and preparing your own data. http://www.globalmapper.com/ Maybe there are some other forum users who might know how to obtain Korean maps? Please contribute suggestions.

In order to perform a site assessment, WAsP checks the entire map. Bigger maps take longer. A complete site assessment is performed for each node, so if the number of nodes stays the same and the map data grows, the job will take longer. For this reason, if you care about the calculation time, it's well worth constraining the vector map to be only as big as you need for your assessments. Don't underestimate the calculation time cost of including irrelevant map data in the vector map. Three tricks can help. 1) Cut the map, so that it does not extend further than you need for your calculations. This extension depends on the height of calculation and the kind of terrain. Generally, roughness changes further away are more significant than elevation changes. 2) Use the map editor to cut a circular map, since the corner data are irrelevant 3) Use the map editor to thin the contour density further from your sites. For example, if you've got a map with 10m contour intervals, then you could make a local map from that extending 1km in all directions, and then make a larger map and thin the contours to 50m. Recombining these maps will give you a map which WAsP can use efficiently.

Not really. Do you mean saving and re-opening the resource grid configuration, height and (if relevant) mask?

Argh! We know that this is needed, but it's a matter of how we spend our available time. The WEng2 scripting documentation was quite a big effort and we still don't really know whether it was worthwhile (because we could just handle individual requests like this instead whenever they arise). WAsP would be a bigger job by far because the architecture is designed to support a much more interactive and flexible workspace GUI. But these are excuses. To be honest we no plans to produce this documentation in the near future. If this is something that lots of people need, then please let us know by posting here to say do, or emailing us directly. Meanwhile, the existing scripting documents do include a list of the common interface library interfaces (Rvea0027). Have you discovered that? I have also run an automatic tool on the WAsP programatic DLL which produces an HTML file with all the interfaces available to WAsP. The DLL is called Rvea0134 in WAsP 10. You can get that HTML file using the following link: http://wasptechnical.dk/Services/Redirect.aspx?token=b1809813-815b-4805-9fab-25f966b37915 Sorry I can't offer more at this stage, but keep asking specific questions here as they arise and we'll try to help

This is a quick reply, rather than a slow, well-researched one, so let me know if it's not useful. The SelectedPerformanceTable property is readonly, and returns a reference to the table object (IRveaWtgPerformanceTable). But the SelectedPerformanceTable index property is read/write, and you can use this to change the currently selected table for calculations. So you need a loop to increment the index from 1 to 6 and perform and record the calculations for the wind farm within that loop. HTH, Duncan.

Hi again Jose, thanks for sending me the workspace. I see what you mean about this problem. But as far as I can tell the calculations are performed twice, not 'at least three times'. This is an error in our code housekeeping (made by me I must confess). It was fixed properly in WAsP 10, but this change has not been carried back to WAsP 9. I'll sort this out ASAP.

Is the default extension for that method really *.map or is it actually *.lib? If it's map then we've got a bug in there somewhere. There is no method on that object (or anywhere else) to get the name of some other type of file. You could use the VBScript call 'Inputbox' to retrieve a string from the user, but that's a bit ugly. We could add a method like this to the next WEng 2.0 release if you think it would be useful. Duncan.

Off the top of my head, I guess that the program is failing to allocate enough memory to handle the results set which would be calculated. This is an huge grid you've defined. Are you hoping to use it in WindFarmer? For now I suggest that you try splitting the grid into four. You will also get some significant calculation time savings by cutting a different map for each sub-grid. Hope that helps, Duncan.

Hi Jose, this doesn't sound right at all. I can't think of any reason for what you see, but I'm surprised that we haven't noticed it ourselves. I have emailed you directly to ask for an example workspace. Has anyone else noticed anything like this with the new WAsP 9.1 release? Duncan.

Hello, WAsP doesn't extract or use any information from Google Earth. GE is only used as a display medium to present the data which are already loaded and calculated in the workspace. Roughness and elevation data are read from the map file. If there's a mismatch with the WAsP data (aerial imagery and 3-D terrain, respectively) displayed in GE, then you will probably notice. All you can do, though, is to revise the data inputs to WAsP yourself. Does that help? Duncan.

WAsP does not calculate shadow maps. But some compatible products do. EMD Windpro has a module for that :(http://www.emd.dk/WindPRO/WindPRO%20Modules,%20shadow) and Garrad Hassan's WindFarmer offers something simlar: (http://www.garradhassan.com/products/ghwindfarmer/flicker.php) Hope that helps. Duncan.