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Where can i find something study about that? -------- "Confidence level estimation - Where can i find something study about that?" There's a brief article in DEWI Magazin Nr. 28, Februar 2006- h-tp://www.dewi.de/dewi/fileadmin/pdf/publications/Magazin_28/07.pdf with references to other work. --------

I would like to know if is available any newer version or upgrades to WAsP after 8.1 version. If it is how can I buy it? Thanks for your time. Vander Apollinario . -------- I would like to know if is available any newer version or upgrades to WAsP after 8.1 version. If it is how can I buy it?" If you run WAsP 8, you should at least install the final version 8.3. You may download this from http://www.wasp.dk/Download/WAsP/PreviousInstallations.html. Current version is 9.0, see http://www.wasp.dk/Order/OrderForm.html --------

Site effects page of met stations and turbine sites has a column "speed up" for each of roughness, obstacle and orography. According to help file, roughness speed-up gives an increase of the wind speed as compared to a terrain with constant roughness equal to the reference roughness. For orography speed-up I can find no explanation, and I guess it gives an increase as compared to a completely flat terrain with constant roughness equal to the reference roughness . Could WAsP team or someone advise if I am correct or not? --------

Hi! On some projects, the time needed to compute the grid WRG is pretty big. I noticed that on multi-core computers, Wasp only uses one core to do the computing. If the software was able to take advantage of more than one CPU at the same time, the speed-up would be significant. So I was wondering if such a version is planned in the near future? Thanks a lot, Eve-Line --------

Where can i found more turbine in my library?? I need turbine characteristics for the small wind turbines from 10 to 20KW?? --------

How can i make wind atlas and predicted wind climate for one region wich contains more(14) met stations in different places. I have map of the region and datas from that met stations?? PLEAS HELp -------- Maybe you have to use the LIB-interpolator... --------

Hello ! I am trying to estimate the wake hours incident on the wind turbines. My aim is to compute the % velocity (energy) deficit. I have the mean wind speed & weibull info for all WTGs in all the sectors from the energy report. Kindly guide on this. Vinod .. --------

Can we inser a and k parameters in WAsP? --------

Hi WAsP team, I am trying to compare a 2D CFD solution to WAsP. To do this, I defined an average wind speed using Weibull parameters in a .tab file. When I run WAsP, the average wind speed of the met. station self-prediction is different than the wind speed specified in the .tab file for the same height (15m). How can I get the .tab file and the met. station self-prediction to have the same average wind speed? Thank you for your help. --------

Dear WAsP team: And I have a question that, if this wind farm is covering a large area (with a relative flat terrain) say, 20kmx20km, and will have 150 WTG. Will Wasp still give good, reasonalbe result.Or there should be some other way around, or special concerns, I mean devided the big wind farm into several one and calcualte on each? The Park wake model will work well or not under such circumstance? Do I need to consider some more roughness changes because too many wind turbines in this case? I don't know whether you could catch my and looking forward to your kind answer! Wang Yang --------

Hello WAsP team, The assumption of a perfect linear relationship between log(Up/Um) and dRIX confirms the prevalence of identical wind regimes at the reference & predicted sites. 1. How can I compute the uncertainties in my AEP results once this linear relationship starts deviating ? 2. As a special case, if both the sites are extremely but equally rugged (i.e. when dRIX ~ 0), will WAsP still operate in it's defined envelopes ? Plz explain. Thanks. --------

WAsP over-estimates AEP in the urban environment, i.e. actual production is nearer 3/4 of the WAsP result. Are there any tricks learned to correct for this ? e.g. I've tried increasing roughness and obstacles with limited success. Perhaps the urban area should be included as an increased height of orography ? Would it be appropriate to consider the city (turbine on edge of) in terms of displacement (like WAsP in the forest) ? --------

Hello, I have realized a wind mapping and I would like to use RIX factor and I have read all documentation. I am sure to type the right command? RIX file.map file.wrg Moreover, how can I write results directly into an ascci file. Thanks, Sandrine BOUISSET -------- Hello, Are you talking about the RIX command line program: part of the WAsP Utility package? Did you know that you can get the RIX values directly from the resource grid inside the main WAsP 8 program? --------

Hi, my I´m a young professor at technical university of Havana . Cuba. I´ve benn working with WAsP 8.2, along with the metheorological institute of Cuba, for to obtain the wind resource map of Cuba, I supose you´ve heard of it (Rolando Soltura). I must present next month the subject for my PhD. degree, and I want to know if a possible one might be the recalculation of some WAsP default parameters according Caribbean climathology, ´cause I´ve found some contradictions between WAsP results and microscale measurments using NRG systems, and the team thinks that might be caused, these contradictions, due to lack of accuracy of some defult parameters. So, the point is if you think that this subject is possible to be strong enough for a PhD. Thanks Andres -------- Dear Andres, greet Soltura from me! I've been there some years ago and gave a WAsP course. To your question: I do not think it would be enough for a PhD to look at the tropical stability questions in WAsP. This is partly because WAsP only supports two parameters where to fiddle with the stability, one of which just needs to be lowered, and the other one is then a parameter of choice. The problem grows to four parameters, if you also look offshore. However, you need very good measurements in different heights, presumably with heat flux measurements (or at least temperature differences), and from a number of masts. Once you have that though, it would be enough for a journal paper (and quite interesting, I might add!), but hardly enough for a full PhD. There might be some more atmospheric research to be done with that kind of dataset, but I'm not the expert there. For inspiration, Sven-Erik Gryning and I did a paper for the conference in Delft in 2004- w-ere we looked at the influence of the heat flux on WAsP. See the Literature part of this website for the paper (http://www.wasp.dk/Support/Literature.html). The short of the long is that within reasonable variation of the parameters, the profile of WAsP is changed only little. Hope this helps, Best regards, Gregor --------

Dear wasp team and forum users, I've read that it is possible to edit the wasp registry file and print a Dump-txt file for the wake model. I'd like to know if it is possible to extract other type of sector-wise and/or bin-wise information. thanks in advance reagrds Andrea -------- The answer was provided in an earlier post on this forum, entitled 'Wind Farm Model / Registry'. It's on the previous page (2005-09-30). Here it is: The wind farm wake model can produce a dump file (as it could in version 7). The GUI does not offer support for this yet, but a registry key is used: HKEY_CURRENT_USER\Software\Risoe National Laboratory\Wasp\Version 8\Application administration\Dump If this is an empty string (default) then no dump file is written. If it says "temp" then a file called "WfDump.txt" is generated in the current users' temp folder. It it says "app" then a file called "WfDump.txt" is generated in the application binary path. If a fully-qualified path name is provided (eg. c:\foobar\windymiller.txt), then that file will be used. If you are not familiar with editing the Windows registry, it is strongly recommended that you have someone help you, who are! The WAsP Team @ Risø --------

Hi i`d like to know if there`s some criteria for to know haow far can i go with grids calculation for one metheorological station? i mean, how many kilometers away can i go in calculation for the same type of landscape? Thanks -------- If I understand well, you would like to know the resources of a site, which is let's say 100 km away from a met. stat. Your question is: the data collected by a met. stat. is applicable this far as well? I would like to know this too. The only thing I've found: http://www.wasp.dk/Support/FAQ/Maps/SRTM2MAP.html In this document at Step 5 it says: 'For a met. station site one might choose to make a 20 by 20 km2 map with 50-m contours, a 10 by 10 km2 map with 10-m contours and a 2 by 2 km2 map with 5-m contours - all centered around the met. station.' I'm not sure, but out of this I drew a conclusion that the range of a met. stat. is no more than 10 kilometers (20 kms in diameter).-------- -------- The criteria itself is simple: The met. station and the turbine site should be subject to the same overall weather regime, i.e. they should have the same regional wind climate (same wind atlas). But how to determine the distance is not so easy... The distance is determined by the change in weather regime with distance; this again depends on the type of dominating weather systems (e.g. Westerlies, Trade winds, etc.) and how these are influenced by the large-scale terrain (mesoscale effects). For simple terrain and cyclonic-type weather regimes (e.g. many places in NW Europe) the distance could be of the order of 50 km, but in places with more complex topography/climatology it might be only 5 km or even less. So, the distance can only be estimated from analyses of the actual place and situation. The WAsP Team -------- This conclusion is not right! The size of the map is determined by the model employed: the WAsP models take the terrain within a distance of about 10 km in to account. So, terrain features further away would influence the model results very little, if at all. Also, the two sites need not be in the same map: You could have one 20x20 km map at the met. station and another 20x20 km map at the turbine site and the distance between the two sites could be anywhere between 0 and, say, 50 km, depending on the topographical/climatological situation. As long as the two sites have the same regional wind climate (wind atlas) then this would be alright. The WAsP Team --------

Hello, Do you have further explanations, than those found in European Wind Atlas, in what extend we can modify the values of average heat flux and root-mean-square heat flux and in which conditions is the most important? Do you know the values typical for North America regions and are they similar to those used in WAsP? Thank you in advance -------- You could consult the paper of Giebel and Gryning on the WAsP web site to learn more about this. The heat flux values are important for the extrapolation of the wind climate to higher heights, i.e. the vertical wind profile. I do not know the values typical for North America (which is also a huge area!), but would imagine that the national or state met. service would have this information. The default values used in WAsP were determined when constructing the European Wind Atlas, so they should be typical for (most of) Europe. The WAsP Team -------- The reference is http://www.wasp.dk/Support/Literature.html. The WAsP Team --------

Hello everybody, can anyone tell me what is the meaning of the function/graph in the "predicted wind climate- PRODUCTION" -window. I first guessed, it is the weibull density function f(u) multiplied by the power curve P(u), but the values don't fit. I am trying to find out for quite some time so it would be great if someone could help me.. byebye Melanie -------- ps: my version is wasp 7.1 -------- Melanie, You are hinting at the right point. The AEP-distribution is basically the Weibull distribution value mulitplied by the production from the power-curve, both as functions of the wind speed. But then there are two additional factors: the sector frequency, and the number of hours per year (24*365.25) to get at an AEP. Remark the the unit is in fact no just MWh - but MWh/(m/s), i.e. per unit wind speed since it is the production distribution and not the total production. --------

Hi Wasp team, if the wind vertical profile is defined with the formula: V = Vref ( ln(h/z0) / ln(href/z0)) where z0 is the roughness length, why, for a given z0, the mean wind speeds given by the Wasp atlas do not match with the formula ? Thank you Regards P.Dauguet -------- You can see the same thing when plotting the predicted wind profile over flat uniform terrain: the WAsP wind profile does not follow the logarithmic law exactly. This is caused by the fact that WAsP employs a simple stability correction, based on the mean and RMS values of the heat flux values over land and sea. If you 'kill' this stability correction - by setting the heat flux parameters to zero - the wind profile should be logarithmic. The default heat flux values in WAsP were chosen as part of the analyses leading to the European Wind Atlas. In general, one could choose values that are representative of the site/region in question. The WAsP Team --------

There are three main methods for estimating weibull parameters. Least Squares, maximum likelyhood and method of moments. The european atlas makes reference to method of moments, but I can find no direct reference anywhere that this is the method that WASP uses - Can anyone confirm the method of weibull estimation used and whether there are any special approaches taken by WASP in the estimation? Thanks -------- WAsP uses the moment fitting method for estimating the Weibull parameters. The method is described further on page 583 in the European Wind Atlas. The WAsP Team @ Risø --------

Dear WAsP team I got the information that by changing the WAsP registry (at Risoe/WAsP/Version8/Application Administration/Dump in the regedit) one could gain access to the possibility of "extrating" Wind Farm models. I couldn't do it. Is this true ? If so, can you explain me how ? Thanks in advance... -------- The wind farm wake model can produce a dump file (as it could in version 7). The GUI does not offer support for this yet, but a registry key is used: HKEY_CURRENT_USER\Software\Risoe National Laboratory\Wasp\Version 8\Application administration\Dump If this is an empty string (default) then no dump file is written. If it says "temp" then a file called "WfDump.txt" is generated in the current users' temp folder. It it says "app" then a file called "WfDump.txt" is generated in the application binary path. If a fully-qualified path name is provided (eg. c:\foobar\windymiller.txt), then that file will be used. If you are not familiar with editing the Windows registry, it is strongly recommended that you have someone help you, who are! The WAsP Team @ Risø --------

I have a little problem regarding a 40m mast, because the mean wind at 40m is a little lower than the mean at 30m (for all the directions...we have just checked the instruments...): it happens with 2 different masts located on 2 different sites. How I can model this "negative wind shear" in WAsP? I have to suppose a roughness 0.00001? Thank you very much Bye -------- The mean wind speed profile is the result of the effects of the terrain (elevation differences and roughness changes) and the site climatology. We have seen 'negative wind shears' over hills even with a roughness much higher than the one you mention. So, first of all, you need to examine your terrain descriptions, ie elevation map and roughness map. Once you are confident that the terrain descriptions are sufficiently detailed and accurate, you may look into other effects - such as the climatological values of the mean heat flux and RMS heat flux. These can be changed in the projects parameter settings and will change the shape of the wind profile. You may enter new values in the WAsP project, corresponding to the climatology at your site, or you can also simply experiment a little - by changing the values - to see the effects on the wind profile. Not knowing your particular site and project, it is difficult to say exactly what should be done, but in general the effects described above are the most important for the wind shear. The WAsP Team @ Risø --------

Dear Is there any paper containing a numerical formula to calculate RWC from measured wind data ?? Can I know the title of the papers or.. would you let me know the formula ??? I can't find nothing but some explanation for this process to calculate RWC. -------- How to calculate/estimate the Regional Wind Climate from the Observed Wind Climate and the topographical descriptions of the met. station is described in the European Wind Atlas. It is not a simple equation, but rather a fairly complicated procedure which involves among other things modelling of the terrain effects at the met. station. The WAsP Team @ Risoe --------

Dear I tried to find the XML editor shown in the wasp help file to read RWC file. So, I got a program which one of XML editor but it doesn't seem to be different with ordinary text editor except some functions. The XML editor shown in wasp help file is designed by risoe ??? Do I need to purchase it from risoe ??? ---------------- Thanks. Vinod. -------- The XML editor shown in several places in the WAsP help file is the Microsoft XML Notepad. Try search the Microsoft web site for more information (our original link does not work anymore...) The WAsP Team @ Risoe --------

Hello WAsP team & respected members, I am Vinod from GEITC (Bangalore, India). Recently I did a roughness digitization of a topographical map for forests, water bodies & settlements. Becoz the map was quite big & especially the forested areas were quite small & fragmented (lying on a part of the map), it took a big time to digitize them all. My question is - 1. If I had opted to digitize the nearby lying fragmented forests altogether (in one shot) instead of doing them separately one-by-one, what % of deviation can I expect when I am to calculate my resource grid & hence the energy output ? 2. The *.map file (which contains height & roughness contours as well) exhibits the losing of roughness info when I load my WindPRO project everytime. So, I have to load the *.map file again. As a result, I converted *.map file into *.WPO format. Why does this happen ? ---------------- Thanks. Vinod. -------- For an area with a large number of small fragmented forest areas we usually recommend to treat the area as one large roughness area with an average roughness. This will be correct within a few per cent (wind speed prediction). Regarding loading orographic and roughness maps in Windpro: I think that Windpro - contrary to WAsP - requires that orographic and roughness are always loaded separately. You will have to ask the Windpro people for the details. --------