WRG point file + energy calculation

Hi Nick, I am a newby of OpenWind. I need to make an energy calculation I loaded an wrg file created by WASP (I don't own WASP), after that I loaded an tab file, also this created by WASP. At this point I imported my turbine site lay-out using open vector layer command. I don't remember the way how I ordered the layer, but I made the energy calculation, with-out I had loaded any WRG-point file into the must layer. 

Can you explain this ?

Can I avoid to load a wrg point file to run an energy calculation ?

If don't, how can I obtain an wrg point file without have any licence of other wind calculation softwares ?

Why should I use an opensource software if I need other software to make it work?

Thanks in advance

Giuseppe

Hi Guiseppe,

Several questions there. First, you don't need a point WRG if you're WRG is created using correct values for the mean wind speeds. SiteWind (an AWS Truewind product) fits this description and I believe most other wind-flow software does too. However, those people at Risoe are cleverer than the rest of us and so they do not always make their Weibulls so that they conserve mean wind speed. This is why you should use a point WRG when using WAsP wind to make your wind-flows. It isn't mandatory in openWind though because other software doesn't need it and anyway, we assume that you know what you're doing.

Second point is that openWind has a built-in wind-flow model so you can always use that. We don't recommend it but it means you can continue to be a cheap-ass and not pay for any software which I believe was your question

Third point is that whether it's free (as in beer) or really expensive, I would choose to use openWind over any of the other products out there due to the ease and speed with which it lets you work. If you're only using openWind because it costs you nothing then please do me the favour of not telling me that.

Have fun using openWind and the user-manual is coming soon.

Nick

All clear, but still I can't run the energy calculation. My hierarchies is this one :

WRG file -- TAB (child)

              -- WIND SPEED (checked) ----- Site Layer (child)

              -- POWER DENSITY (unchecked)

              -- ELEVATION (unchecked)

I have tried many kind hierarchies, but always appears the same error message :

"turbine 1 of Site Layer(xxxxxxxxxxxx) doesn't have access to an appropriate WRG.

What should I do Nick ?

Thany you

What is the hub height of your WRG? What is the hub height of your chosen turbine? I just tried that hierarchy and it works fine for me so it must be something else.

Nick

mmm strange. My turbine hub eight is 100 mt and the must id 40 mt.

Thank you Nick.

Giuseppe