Solar Access Analysis error

[road619runner]

I have a little problem with the solar access analysis, I create a model with sketch up, exportrted in DXF and tryied the solar access analysis.

All worked well, only one problem, some surface  reiceve the sun from the wrong direction and it give me a wrong result...

How can I resolve this problem?

Is like if the sun try to illuminate surfaces in the internal part of the building.

thx a lot

[Pennetier1 · Accepted solution]

Hi road619runner, 

The reason some of your surfaces are not receiving solar radiation is indeed because their surface normals are not pointing out to ward the sun.

It is difficult for Ecotect to always figure this out from an import from another CAD file, and it is very common for import from Sketchup to have the surface normals of the WALLS objects to all be reversed.

Often time, that is an easy fix.  You can go to the Select menu > By Element Type > Walls.  This should select all the WALL objects.  Press Crtl + F9 to display the surface normals.  They are probably pointing inward.  Press Crtl + R to reverse all these selected surface normals so that they now point outward.

If the surface normals are all over the place (some inward, some outward), then it will take a bit more work to go through each ones. You can also use the Select menu > By Orientation to help you select the objects that need to be reversed.

I hope that helps.

Let me know if you have more questions on this topic, otherwise please accept as a solution so that others can benefit from this information.

Cheers,

[road619runner]

I'm in the situatin. Some surfaces have the right orientation, but only few surfaces are at the reverse.
So I have to' go on orientation and add 180 grados to' the orientation?

[Pennetier1 · Accepted solution]

road619runner, 

You can simply select these objects and press crtl + R.

Cheers,

[road619runner]

Now can I control the orientation of the surfaces before the simulation?
After the simulation I put "show vectors" and all the arrorw are from the surfaces to' outside the building. I'll attach you a picture.
Is it right?

[Pennetier1]

Hi road619runner, 

Yes, you can always control the orientation of your surfaces, whether through reversing its surface normal, or under the Selection Information control panel > Orientation > Azimuth/Altitude.

The vectors that are displayed after the calculation do not represent surface orientation; they are only a graphic representation of the results from the Object Attribute.  So if one object receives 2,000 Wh of radiation, it will show a longer vector arrow than another surface receiving 1,500 Wh of radiation.  It has nothing to do with surface orientation. The feature can be useful to quickly see what area of a surface has the highest value of the calculation.

I hope that helps.

Let me know if you have more questions on this topic, otherwise please accept as a solution so that others can benefit from this information.

Cheers,

[road619runner]

Thx for the reply, when I go on azimuth, orientation, it doesn't show me the orientation with an arrow...only with a number, there is a way to show it?

Inviato da iPad

[Pennetier1]

Hi, 

To show the orientation of the surface normals, press Crtl + F9.

Also, there is an option under User Preferences (Crtl + Shift + P) > Options > Display Directional Arrow for Selected Objects;  so that any selected object in your model always show their surface normal.

I hope that is what you are after.

Cheers,

[road619runner]

thx for all the answer.

It was a very clear explication, and most important confirmed that I made the thing in the right way... following a different way

the last thing that I have to ask to you is that. when I use copy as image JPG I can save only the model without the legend?

I explain better: in the solar access every color has a value, I put show legend but I print only the mode without the text...

I have to print it as PDF file? And instal a PDF plotter? (retoric question)

[road619runner]

what should appear,

 what I capture with the JPG.

No appear the legend and the text

[Pennetier1 · Accepted solution]

Hello road619runner, 

I am aware of this issue. Back a few versions, Ecotect had to create a "Disable Aero Theme" to be able to capture the image.  That was when Windows came up with Vista and its Aero Theme.  Now with Windows 8, the Aero Theme is automatic and so Ecotect cannot disable it (the button is still in Ecotect under the Tool menu > Create Animation > Disable the Aero Theme button.)

Unfortunately, there isn't much you can do, as far as I know.

What I do is capture a screen shot using Alt + Print Scrn.  I am then able to edit the image in an image editor if I need to.

Maybe someone has another option?

Cheers,

[road619runner]

I capture the image twice only to know the scale of the model...
With alt+print the quality is not so high... So I think I'll copy the scale on the jpg o bmp

[road619runner]

Could the winter solar radiaton to be higher than the summer solar radiation?

In Italy

[Pennetier1]

Hello road619runner, 

Typically, summer radiation will be higher than winter radiation, not because the sun is farthest from the earth (it is actually further in the summer), but because of the angle of the earth.

With that said, there might be some cases where winter radiation could be higher if summers are particularly cloudy.  Also, interestingly, some locations receive their highest electrical output from solar panels in the winter time, when the skies are clear, such as high elevation locations, and the snow reflects extra radiation on the panels.

You may want to double check your weather file in the Weather Tool, and compare it to known meteorological data to make sure it is accurate.

What is your particular location? Where did you get the weather file from?

Cheers,

[road619runner]

I used a wether file download from the  link suggested by ecotect...

I know that  the summer radiation should be higer in summer that in winter, I tried 2 times

[road619runner]

weather file

I uesed that archive to do the simulation, some of this is not in the right format and I had to convert in a wea file...

[Pennetier1]

Hello road619runner, 

I can only see that it is a weather file for a French city; if you attach your .wea or send it to me via email, I can have a look at it to see what might be off with the file.

Thanks,

[road619runner]

i can't attach here the .wea file. but i convert the epw file into a wea with ecotect

[road619runner]

how can i put here the wea file? or the zip file?

[Pennetier1]

Hi road619runner, 

You can either attached a zipped file to this post or email me at olivier@symphysis.net.

Cheers,