Sun elevation and azimut

pvbuero · 6 Jun 2010, 17:47

Hello,

recently I found out, that there are some ways to figure out the current direction of a vector pointing to the sun, the sun elevation and the azimut angle of the sun in a sketchup model using dynamic components.
Now my question is if there are methods to retrieve those values in a rubyscript. I couldn't find anything like this in the shadowinfo class... Is there another class which I didn't find yet ?

As always ... thanks for your help.
MD

thomthom · 6 Jun 2010, 18:24

The API docs are incomplete.
For a complete list:

Sketchup.active_model.shadow_info.each { |k,v| puts "#{k} - #{v}" } City - Boulder (CO) Country - USA Dark - 45 DayOfYear - 312 DaylightSavings - false DisplayNorth - false DisplayOnAllFaces - true DisplayOnGroundPlane - true DisplayShadows - false EdgesCastShadows - false Latitude - 40.017 Light - 80 Longitude - -105.283 NorthAngle - 0.0 ShadowTime - Fri Nov 08 14:30:00 W. Europe Standard Time 2002 ShadowTime_time_t - 1036762200 SunDirection - (-0.423824071310226, -0.772439983723215, 0.472979521886207) SunRise - Fri Nov 08 07:43:14 W. Europe Standard Time 2002 SunRise_time_t - 1036737794 SunSet - Fri Nov 08 17:46:34 W. Europe Standard Time 2002 SunSet_time_t - 1036773994 TZOffset - -7.0 UseSunForAllShading - false

Word of advice: never trust the docs.

pvbuero · 7 Jun 2010, 13:00

Hello Thomas,

that's great. What would I do without your help ...
I guess there's no function for the azimut- and the elevation-angle ?
... because it can be calculated with some pythagoras and the SunDirection.
Another question:

Is there a way to find out whether a face is shaded or in the sun ?

Best Matthias

DavidBoulder · 7 Jun 2010, 19:50

Matthias, asking if a face is shaded or in the sun is tricky, because it may be partially shaded.

If you query all of the verticies you could put it into one of these groups.
A . mostly sun exposed
B. partially sun exposed
C. mostly shaded

The reason A and C are not complete is that even if all of the vertices are in sun or shade, there may still be points along an edge or in the middle of the face where there is a different sun condition.

Loosely related to this question, if you choose to do an energy simulation with EnergyPlus (using the OpenStudio plugin or another tool) you can run the "Shading Summary" report to return the fraction of each window that is sunlit at 9am, noon, and 3pm on (March 21, June, 21, December 21st). Here is a link to PDF with a sample of that report. Again this isn't direct out of SketchUp, but is processed through EnergyPlus
http://apps1.eere.energy.gov/buildings/energyplus/pdfs/OutputDetailsAndExamples.pdf#page=140

pvbuero · 21 Jun 2010, 20:21

David,
what I' m looking for is a tool to create something like it's shown in this diagramm.

.. is there any Sketchup Plugin to achieve this ?

Best Matthias

DavidBoulder · 21 Jun 2010, 20:51

There are a number of energy simulation plugins that can probably give you this information. OpenStudio mentioned above which is a plugin that works with EnergyPlus would work, although you would need to edit the file externally to setup surfaces as PV systems. We plan to add that in directly to the plugin in a future release.

You can see the link above directly to the OpenStudio site, and below I have a post showing some screenshots from OpenStudio.
http://forums.sketchucation.com/viewtopic.php?f=323&t=27908&p=241905&hilit=OpenStudio#p241905

wind-borne · 21 Jun 2010, 22:01

LightUp shows similar to your example. here's example I posted awhile back.

http://forums.sketchucation.com/viewtopic.php?p=226729#p226729

pvbuero · 23 Jun 2010, 07:55

@wind-borne said:

LightUp shows similar to your example. here's example I posted awhile back.
http://forums.sketchucation.com/viewtopic.php?p=226729#p226729

Hello,
I checked Lightup sometimes ago but there were to many functions I don't need and I wasn't able to figure out how I could create a diagramm as it's shown above. I usually don't need rendering software. I only need the solar simulation part ...
Is there a tutorial somewhere how to do that with Lightup ?

I will also take a look at open studio...

Thanks to all of you
Matthias

danbig · 25 Jun 2010, 05:39

Regarding the solar elevation (I'm guessing you mean the "incident" angle of the sun with respect to the ground) and azimuth angle... I believe these values could be derived from the SunDirection as described by thomthom.

AdamB · 25 Jun 2010, 06:35

@pvbuero said:

@wind-borne said:

LightUp shows similar to your example. here's example I posted awhile back.
http://forums.sketchucation.com/viewtopic.php?p=226729#p226729

Hello,
I checked Lightup sometimes ago but there were to many functions I don't need and I wasn't able to figure out how I could create a diagramm as it's shown above. I usually don't need rendering software. I only need the solar simulation part ...
Is there a tutorial somewhere how to do that with Lightup ?

I will also take a look at open studio...

Thanks to all of you
Matthias

Matthias,

Its pretty simple to do in LightUp.

Set the geo-location and date for your model using SketchUp "Model Info.."
Choose "Lux Contours" + "Insolation" in LightUp preferences.
Click on Tourtool.

You can use Apple/Alt + mouse click to take exact readings on any part of your model.

Adam

pvbuero · 28 Jun 2010, 10:03

Adam,

I tried it. It is very close to what I need.
I give you a PM with further details.

Matthias