Possibility to define mast-map in WAsP

[MarkHerskind]

Hi..

I am currently working on a project including nine masts. In this project I have forestry(/roughness) maps for 2010, 2020 and 2030..

The hassle is, that I need to add the current map (2010) for all wind-atlasses and another map for the turbines.. In all, I end up adding 10 maps to the file.. This results in a large .wwh file and, which is more annoying, a heavily increased save-time..

As the mast-map normally is the same for all masts, it would be a great feature if you could add a mast-map, that is to be used for all wind-atlasses in the project..

I should probably add, that I'm using WAsP 9, so please have me excused if the feature has been implemented in WAsP 10..

Yours
Mark Herskind

[Duncan]

I'm sure that WAsP 10 doesn't add support for what you need, so don't worry about that!

But I'm intrigued by your problem, and I'm not sure I understand the workspace arrangement. WAsP doesn't offer any automatic way to reconcile multiple atlases generated by multiple masts.

If you have multiple atlases, then you probably have multiple projects in one workspace. Is that right? Do you have the same arrangement of turbine sites in each of several projects: one for each atlas?

Maybe I'm confused, but I think you could do it this way..

Create a workspace with a project in which you have your 2010 map. Then add an atlas, with a met station and OWC. This is one of your masts.

Then insert your turbine sites as a wind farm. Right-click the wind farm, and select 'Extract locations and copy to clipboard'. Then right-click the project and choose 'insert turbine sites from the clipboard'. Do this twice to set up three wind farms with identical sites and heights. Now, under the new wind farms you can insert different maps (2020,2030). The original wind farm will use the project map, but these other maps will override the project-level map for the other wind farms. So your project can give you predictions for each decade.

But so far you're only using one mast. If you drag out the current wind atlas to the workspace level the met station and OWC will go with it. They can just sit there peacefully until you need them again. Now you can insert a new atlas, and use the second mast location and data. It will pick up and use the project-level 2010 map. You can keep doing this until you've got all nine atlases and masts in the workspace, and all three decade predictions in the project. To use different masts, just drag the relevant wind atlas into the project. The one it replaces will be automatically bumped out to the workspace level, so that's a fairly convenient way to switch between different masts.

Does that help/make sense? Would you actually like direct support in the software for roughness length evolution over time? How are you going to choose which of the nine mast locations to use for your AEP predictions?

[MarkHerskind]

Thank you for your answer..

They structure of my project is as follows:
Project
- Wind farm
- - Map
- - WTG
- - Turbine group (Mast1)
- - -
- - - Wind atlas
- - - - Met station
- - - - - Observed wind climate (mast1)
- - - - - Map 2010

- - Turbine group (mast2)
- - -
- - - Wind atlas
- - - - Met station
- - - - - Observed wind climate (mast2)
- - - - - Map 2010

etc...


In my project I have 9 masts, and therefore 9 mast groups..

My point is, that for every mast i have the 2010 map added.. This allows me to change the map in the parent Wind Farm, to let simulate the flow seen by the turbines with other future maps (other forestry)

This results in that I have 10 maps in the file.. (1 for every mast and 1 in the parent wind farm)..

My suggestion is, as all mast uses the same 2010 map, to make a function that will allow a mast-map, so that all nine masts uses the same map, so that it is only necessary to save 2 maps to the file..

Regarding AEP calculations, the AEP for the turbines in "Turbine Group (mast1)" will be calculated from mast1 and so on..


The program works as it's is supposed to, the only thing I'm talking about is, that when WAsP has to save 10 maps to a file it takes quite a while and the .wwh will be quite big.. So the idea is, that if you only need to save 2 maps to the .wwh, the save time could be reduced dramatically..

Yours
Mark Herskind

[Duncan]

OK I think I understand better now.

Whatever the workspace arrangement, there might sometimes be cases where it's convenient to have the same map appearing in two different places. So saving that workspace will always mean compressing and saving redundant information. I guess we could introduce some kind of equivalence check and save just one map to file. That would be quite straightforward.

Your particular case can't really be avoided by re-organising the hierarchy. WAsP rather assumes that one project/one atlas is the normal use case. But I wonder if you could pre-calculate the wind atlases, and then remove their OWCs and maps? Unless you're going to update the data, the atlases won't change.