Transparent Material Analysis

Hi All,

I’m currently doing a quick project study on the use of a transparent canopy for a train station. I want to analyse the outdoor thermal comfort under a large canopy that will either be designed as an opaque metal roof, a 20% transparent integrated glass PV roof or a 100% transparent glass roof.

I seem to have immense difficulty in finding some way of making the shading context transparent! I would like to initially look at the radiation analysis in Ladybug, but I can’t test the 20% transparent option for the context (even in trying to use the HB object shading surface).

I have played around with the example files for the outdoor microclimate map, and the urban microclimate, both of which do not seem to work.

Any help would be greatly appreciated as we are hoping for some preliminary results before the end of the week!!

Kind Regards


PS. below are the files which I am working from - none of which I can get working well.

Solar Radiation (712 KB)
UTCI (525 KB)

Hi Elly,

I just added a transmittance input on Ladybug_Radiation analysis yesterday and this will allow you to account for the transparent canopy in this simple radiation simulation. You can also always use the Honeybee radiation analysis for more detailed transmittance studies with Radiance.

Fianlly, you can model a transparent material in the microclimate maps using the following example file as a guide:
Note that you want to set the transmittance on both the E+ simulation and the view factor component.

As a small note, a glass canopy would still be a different from no canopy at all as clear uncoated glass usually has a transmittance of ~85℅.

Hope this helps,

Hi Chris,

Thank you for your response! These look great, though for some reason I’m throwing up errors with Openstudio. Do you know what might be wrong here with this error message? I have just recently installed OpenStudio and have EnergyPlus 8.5

Hi Chris,

I just want to follow up about the transmittance input on ladybug Radiation analysis. My version is 0.0.66, which version of ladybug include that function? should I download a new one from food4rhino?

Hi Sally @Sally1013 , could you solve the problem? I could not see any component that takes transparency as input when calculating solar irradiance.

Hi Ipek,

The latest version of LBT has these various modifiers that you can apply to say an aperture to simulate transparency. The simplest way to do this would be to use the glass modifier and set a transmittance, although the translucent modifier is the more accurate way to go if you know more about you material properties.

I’m not a radiance expert though, and don’t have a complete grasp on accurate modelling translucent surfaces.

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