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how to define the location of lights in Openstudio

asked 2016-05-09 14:54:20 -0600

updated 2016-05-10 05:46:03 -0600

So far I have found " light definitions" in OS, And I would like to know how can I define the location and position of my lights in my model (Sketchup or even OS)? for this purpose radiance should I use or energyplus is enough? Thanks in advance for any guidance.

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answered 2016-05-10 09:51:58 -0600

updated 2016-05-10 10:03:09 -0600

@OS_4design, unfortunately -- and contrary to appearances in the SketchUp plugin -- you cannot spatially define luminaires in OpenStudio. Well, you can, but all that gets rolled up to the actual simulation models is a load schedule. We regret this confusing presentation.

The plan was to leverage Radiance for spatially honest lighting layout representations, and to answer your question Radiance would be required for this; EnergyPlus is completely unaware of spatial luminous distribution. The plan was to be able to support this in OpenStudio by placing luminaires, associating a photometric distribution (IES) file to each one, and doing an electric lighting simulation with Radiance. We just never got there.

The OS:Luminaire object is still useful in the sense that you can use them to define your lighting loads at that level, but they are "flattened out" to these simple space-level lighting loads. An ambitious user could use the API to write some sort of luminaire-to-Radiance exporter, just sayin'. ;)

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@rpg777, Thank you for your informative response.

4Designer's avatar 4Designer  ( 2016-05-14 05:38:44 -0600 )edit

Do you know if anyone ever integrated this with radiance?

Ski90Moo's avatar Ski90Moo  ( 2021-02-26 13:12:27 -0600 )edit

answered 2016-05-10 08:50:21 -0600

If you're talking about the 3-D placement of luminaire objects in the model, this can be done in Sketchup as shown here. As that page mentions, these should refer to OS:Luminaire:Definition objects instead of Lights:Definition.

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@Eric Ringold, Thank you for your response.

4Designer's avatar 4Designer  ( 2016-05-14 05:43:16 -0600 )edit

answered 2016-05-10 06:05:32 -0600

There are two places where you can do that:

  • At the SpaceType level Light Space Type

  • At the space level (what you see in green is because it's inherited from the space type that I have defined) image description

See the Inheritance diagram here

You'll notice that the internal loads (people, lights, etc) are the only things that are actually summed between what's defined at the spaceType and the space itself.

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@Julien Marrec,Thank you for your response.

4Designer's avatar 4Designer  ( 2016-05-14 05:43:49 -0600 )edit

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Asked: 2016-05-09 14:54:20 -0600

Seen: 711 times

Last updated: May 10 '16