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I am trying to model a coastal site. We have 2 masts one 200m-fr-m the sea and another 1km from the sea. The mast correlate well but it looks like the wind speed drops quicker as yuo travel in land. Is WAsP good at modelling coastal sites andd can you recommend any WAsP settings or extra measurements that would improve the modelling. jon -------- For coastal and offshore sites, it is really important that you use the latest versions of WAsP: i.e. WAsP 8.4, 9.1 or 10.0. The stability correction for over-water conditions has been changed in these versions, compared to all previous versions. --------

When can we expect version 10? In other words, how soon is soon? :D Thanks in advance -------- Hello, How soon is soon? Not soon enough, is surely the answer! We're really keen to get WAsP 10 out at last. Our sincere goal is to release it before the end of August. -------- That's GREAT NEWS!!! Hardly waiting the new release , I read about new capabilities of WAsP 10 in DTU 2009, and was amazed. Cheers -------- Just a quick update on the release. Sorry to say that it's going to be a couple of weeks more. Our plan to release in August was derailed. We're working on it, though. --------

Hello, how to overlaying resources grid results using google earth including WAsP wind turbines symbols (logo/icon)?. Thankyou -------- WAsP 10 has some new features which will support this kind of thing. The release will be soon. -------- I have ever done overlay result of resource grid in google earth, but the file must converted using global mapper then export the file as kml/kmz and the turbine site must be create one by one in google earth. -------- In WAsP 10, all you need to do is choose the map projection settings and press a button. --------

Hello all, I have received a new desktop (dell Optiplex 960) with a different model video card (ATI Radeon HD 3470) and am now running WAsP 9.1. When I open a workspace, double-click on a resource grid, select "Spatial Grid" tab and choose AEP from the drop down, and then maximize the window and zoom, often only the upper left-hand quadrant of the grid will have any color, and the rest will not. Has anyone seen this issue before? It is very urgent that I receive some guidance on this error. thank you, Vijayant -------- Hello, Was this resource grid was previously calculated? Was it displaying correctly on your old computer? Does it display correctly on another computer? Does it display correctly if you don't have the window maximised? Can you try using the standard WAsP sample workspaces. Do you see the same phenomenon? --------

How can I merge a WRG from several wind atlas (several masts on a large site)? -------- Hello Cathy, There are no easy ways to do this, but can you say whether the grids overlap each other? -------- I can make the grids bigger enough to overlap, but those are large grid, in complex terrain, and the masts used to generate WRG can give noticeable difference on mean wind speed on the overlapping areas. My wind farm extension is 20 km wide minimum, with 3 masts (on a row for exemple) to make 3 differents WRG of about 7 km wide. -------- Hi Cathy, Sounds like you have two questions/problems. One is technical: how can I merge several resource grids? The other is scientific: is it OK to merge several grids in this case? We don't have a tool that lets you merge the grids, but if this is something that you and others are needing to do quite often, then we could write something that does that (it could be a utility script). The question about overlap arises because if they do overlap (or have gaps, or have different resolutions) then a decision is needed about what to do when merging. If you have four square grids which together neatly form a larger grid, then merging is technically quite straightforward. As for the scientific question, I'm not really qualified to advise. For what it's worth, though, I would say that if the different atlases are giving different results for the same location, you've got to work out why and what you want to do about it, before thinking about the technicalities of merging. It's probably more correct to handle the differences at the wind atlas level than at the site level: I think you should not average or interpolate the site results, but go back to the wind atlases and work out which is the right one to use for the overlap area. You could use the lib interpolator tool to interpolate new wind atlases from your original three, and use these to generate more grids until the edge overlap results look more similar. Again, I offer these remarks as an unqualified WAsP user, not as a WAsP scientist. Perhaps others here have experienced this situation and can suggest some ways to handle it. --------

Hello, does grid validity resources assessment analysist using observed wind climate from a location for other location apart distance of 50 kms? if yes, does enough by changing its(the map of vector is only? --------

does grid validity resources assessment analysist using observed wind climate (24*50 a.g.l) for area wide 200--00-sq km? -------- Are you asking whether you can calculate site resource estimates using a lib file derived from data collected 22km away? -------- Yes. -------- Hello, I guess it depends on how uniform the area is. How different is the measurement site from the resource assessment site? Have you checked out the latest 'Best practices' sheet from the WAsP scientists? http://www.wasp.dk/Support/DownloadFiles/WAsP_best_practices_27Mar09.pdf Maybe there are some pointers there --------

when l used the resource grid of wasp ,the window always shows "the system reported that: the divisor is zero,who can help me to solve the problem! -------- This sounds like a technical support question. I have responded to you directly by email. --------

Good morning, I have a couple of questions i'd like to ask. To beguin with i don't know if there's a limit on the number of data/files that the OWC Wizard can handle. I'm trying to analyse up to 17 years of wind raw data, and i positively know the wizard it's not reading all data. Besides, i have one year of readings wich has a maximun speed of 45,7 m/s,(287º) the next higher speed it's 31,4 m/s(83º).Once i pass this file through the OWC Wizard, the report shows 2 readings at 46 m/s (290º), and six readings at 32m/s (80º). Finally i'm aplying the delta-RIX method, i would like some bibliography about it, but i haven't found it, maybe you know about some. Thanks so much for your time. Diego -------- Hello. It's going to be hard for us to investigate this without the data. In fact the OWC Wizard is a rather limited utility program and has been replaced by the WAsP Climate Analyst, which is more powerful. It's not a perfect program by any means, but it should be much more straightforward to manage 17 data files than with the OWC Wizard. Could you try using that instead? If you still have problems, email us at waspsupport@risoe.dk and we'll look at it in more detail. -------- Literature about the delta-RIX method is listed on http://www.wasp.dk/Support/Literature.html. --------

I did simulation on field with hills and forest. The anemometer data are measured at 40 m. The estrapolated wind speed at 85 m is overestimated. Why do WAsP overstimate the speed? Can I correct the wind shear only changing roughness or height of displacement? Is it a WAsP limit? -------- The wind profile depends on the quality of your elevation and roughness descriptions, and the exact prediction also on the quality of your data. In addition, the heat flux settings will influence the profile. Without looking at your project in some detail, it would be difficult to say something sensible about the predicted wind shear - including whether it is too large. --------

Hello; I have the license for WAsP 8.1, it's an educational one. The problem is that new computers don't have anymore a place to attach dongles, and using a tranformer into USB just don't work. Is there anything i can do? Thanks in advance Diego -------- You have one of the old parallel port dongles, I guess? So if your new PC can't work with that, then you need to arrange an exchange (to USB dongle). Email wasplicence@risoe.dk and ask for pricing and instructions. --------

What is the WAsp Correction factor of 2~3 % used in arriving at the final Capacity utilization Factor. Is it to take care of abnormalities in the software? -------- I have no idea what you refer to - could you be a bit more specific, please? --------

I am a WAsP 9 user. Can I convert a file .rrd version 6 to my version 9 or can I use this file in my WAsP 9? -------- AFAIK, you can open an RRD file straight into WAsP 9. Let me know if you have any problems. --------

I need to predict the production of a windfarm with a power limitation of 10MW but has 12MW installed. This means that at any time there is enough wind for the wtg's to produce more than 10MW, the power would stay at 10MW. Does anybody know if it is possible to do this with WASP? -------- You will need to constrain some of the WTG's, consult the turbine manufacturer, they may oblige to provide you with a constrained power curve. Cutting the respective power curve at a certain point is another option. In practice the turbines would be "tuned" down slowly, with the rated power at a each given wind speed being reduced. --------

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 -------- 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 -------- 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. --------

I have also a question about self prediction: is it possible to correct this effect when the difference between measured wind speed in .tab file (OWC wizard) and the self prediction exist? If yes, how? In some cases the difference is as large as 0.2, 0.3 m/s and this will affect the entire .wrg file or .rsf estimations because wind speed at mast position will be higher then measured wind speed. --------

Hi, i have a very basic question on WAsP: when i make the self-prediction of the wind on a met station, why do i have an error on the wind speed? i.e. If my measured wind speed is 5.00 m/s, why do i have a self-prediction of, say, 4.95 or 5.02 m/s? I understand it's the result of "going up" to the wind atlas and then back to the met station site, but what's the technical reason of this? If i don't obtain the same numbers, it means that the "uopgoing" transfer function and the "downgoing" transfer function are not the inverse of each other, right? Is it a binning effect or something? Thanks a lot. Alessandro Palma --------

Hi, I am a new user of WAsP v8 and I am a bit lost. I have two different projects to solve: 1) I have loads of data (4 million readings) from a met. station, in access. What do I have to do with this in order to create a valid .tab for WAsP? Which values are important...? 2) The other project I do not have measurements but I do have some results from a nearby wind farm (total mean speed,1&2 main directions(most frequent),1&2 frequency of main direction, 1$2 mean speed of main direction, max speed, direction max speed, weibull factors: A & K ......) The question is: Is there a way of using some of these data instead of all the measurements? if it is, how? Thank you very much, Lucas -------- It doesn't sound like you can use the readings from the wind farm, but the data from a met station should be OK. 4 million points? Is that 76 years worth of data? Or from multiple heights, or is the stride quite short? From Access, you should dump them to a text file of some kind.I urge you to use ISO Date formats for the export, with four digit years and leading zeros, and I suggest using TAB as a delimiter. With WAsP 8, you don't get the ClimateAnalyst program, but you can download it and use it from http://www.wasp.dk/Download/WAsP.html. Then you could use it to load and examine the data. Your WAsP 8 licence will not let you calculate a TAB file from these data, though. WAsP 8 comes with the trusty old Observed Wind Climate Wizard program which you should be able to use to import the ASCII time series data and calcuate an OWC (Tab) file. -------- Ok, so I can´t use the readings from the WindFarm! :( The 4 million measurements correspond to bat. level, wind speed1, wind speed 2, wind direction1, wind direction2, and air temp. taken every 10 minutes for 5.5 years. About the way of dumping te data on to a text file, could you please give me an example, i.e how many columns? what data in eac column, and what data in each line? Do I have to make any previous calculations with an excell sheat?Like mean wind speed every so many hours or something like that? Sorry, but as you can see I am totally new in this. thank you so much, Lucas -------- So there are no time-stamps in your logger output? For simplicity, I suggest that you simply export windspeed1 and winddirection1 to a text file in two columns, separated by a space or tab. Then fire up the OWC wizard and start importing the data. Look in the WAsP 8 help file for instructions (Section: WAsP tools and more... The OWC Wizard.) -------- HI, I´ve tryed that and I think it works, but comparing with another result, the speeds are higher than what should be. When I treat data to paste on to a .txt, which data should I be treating with, average, max, min, or sigma(I suppose that is desviation). I´ve used average, should I use minimum? Thanks -------- For WAsP energy predictions, you should be using the mean wind speed. -------- Ok, I found the problem. The speed was scaled to E:0,1. Now, next step: I have a map with .dxf extention. How do I convert it into a valid .map? Thank you once again!!! -------- I suggest that you open the WAsP help file and search for 'dxf'. --------

The WAsP elaboration, for 1 met. station, is function of the vector map extension? I mean the feasible calculations near met. station change with map dimension? Regards, Marco -------- I'm not sure that I understand what you are asking. The WAsP help file says... "An adequate height contour map should cover an area of at least 10 by 10 km, i.e. the map should extend to at least 5 km from any calculation site. The height contour interval should be less than about 20 m. The extreme elevation points in the terrain, hill tops and crests, should be specified as well." This is from the 'orographic flow model' section. Does that help? -------- Yes, thank you. --------

Hello, I want to calculate the ruggedness index but I don't know how I could start this calculation. Could anybody plese give me a few instructions? Thank you Philipp -------- If you want a grid map of RIX, then just open a new project, insert your vector map and then add a resource grid and calculate it. One of the available results is RIX. --------

Hello, I would like to prepare Wind Atlas for one licalisation. I have already prepared a vector map and Observed wind climate (made by other person), so I'm following these steps: 1. file --> New workspace, 2. a right mouse's button and insert new --> wind atlas, and there is a problem here: "calculation constraint; there is no observed wind climate associate with the wind atlas", and "the met. station should be located in a map, but it is not", hmm... I know what to do next, but I'm not sure how to get rid off that problem. Thank U in advance for Your help. -------- I would suggest that you run through the step-by-step exercise in the Quick start tutorial section of the help file. It's really very quick. Otherwise, you could open the sample Waspdale workspace and see how the hierarchy is arranged in order to calculate a wind atlas. -------- I was repeating the step-by-step example of the tutorial.and I found a cramped detail in the waspdale airport obstacle group map.I noticed that the 8th obstacle's bearings of the 2 corners are 304.9276 and 305,and the depth is 147,which are totally different from the 6th and the 7th. I want to know whether the data input in this way will influence the result of the wind assessment or not.Thank you! -------- Helo Xiaolan Lee, I don't recognise the numbers you reported there. I expect that there is a problem. I'll email you directly to ask more about this. Here is the correct list of values for Airport.obs Obstacle ID angle 1 [°] radius 1 [m] angle 2 [°] radius 2 [m] height [m] depth [m] porosity 1 11 134 26 120 6 30 0,00 2 26 120 43 110 6 60 0,00 3 112 500 146 74 5 16 0,40 4 200 -0 -48 76 4 26 0,00 5 215 154 237 144 6 46 0,00 6 278 116 352 150 6 6 0,70 7 295 150 345 196 6 6 0,70 8 305 196 341 250 6 6 0,70 Duncan. -------- But I downloaded the demo this morning. I have replied your letter several minutes ago,and I attached the requisite files also. Good luck. -------- There is an anomaly in the airport.obs data set, where the first visible face of the eighth obstacle is actually the very short one at the end of the line, rather than the long one which seems to be facing the origin of the group. So the strange numbers you see are a correct way of expressing the same information. When the obstacle is translated to cartesian coordinates for the shelter model, the same obstacle is represented, and the results are the same.

Hello, I usualy plot a basic "WAsP wind shear" at the met mast. For this, I create a wind farm with different wind turbines at different height (every 5 meters). I have done this for many sites , and I have always noticed a little bump in the wind shear at 50m exactly (not always visible just by ploting). The mean problem with this bump is, if i compute with an anemometer under 50 meters I m going to overestimate the wind (and the production) So, Is someone know something about that, is it due to the heat flux? Thanks --------

Hello WASP-Team, I think a lot of people had the same problem than me in the past. Will it be possible in the future to create a LIB out of two TABs? Sometimes it happens that the wind profile on the site cannot be fitted with WASP compared with the results of a met mast measuring at two different heights (vertical distance > 20 m). In this case it would be a great advantage if the regional climate may be calculated with these two results of the met mast. Thank you for your response Thomas Arnold -------- No, this is not likely to happen anytime soon... If WAsP cannot predict the vertical wind profile at your mast, it is better to try to understand why this is so - rather than mixing all the data in the same pot and stirr... The elevation and roughness descriptions should be checked (and maybe changed), and you might also look into the stability effects (heat flux values at the site). --------

The entire programe of WASP is already installed. However, I cannot find the sample data at my computer. Why? Thank you for helping. -------- We know this is a bit confusing. We're trying to follow the XP/Vista guidelines about where to install application data. Unfortunately it goes to a hidden folder! On an English language XP, it goes to C:\Documents and Settings\All Users\Application Data You can navigate there by entering the path to the explorer bar. You can also use the find tool with the option to include hidden files and folders switched on. Any suggestions about where would be the most appropriate place to install these sample data? --------

Hi, I'm running Wasp 8.1. I have put in a dummy roughness line on top of a map containing height contours (imported via .dxf file) but when I try to calculate a resource grid, I get an error saying: Could not do the calculation because ... failed to calculate the resource grid results because ... could not perform a resource grid calculation because ... could not perform a resource grid calculation because ... a problem arose while calculating the grid site with co-ordinates (3633000,3358400) because ... could not accept new sector frequency for a Weibull wind because ... failed to handle the toolbar click because ... failed to calculate the resource grid results because ... could not perform a resource grid calculation because ... could not perform a resource grid calculation because ... a problem arose while calculating the grid site with co-ordinates (3633000,3358400) because ... could not accept new sector frequency for a Weibull wind because ... the system reported that: 'Local exception: The frequency must range from 0 to 1.' If the roughness line is in a circle or runs from east to west it works fine, but if I put the line from north to south (along a coastline) it throws up this error. Can anyone help? Thanks, Lucy --------