Is it possible to create light shelves using the openstudio or sketchup interface instead of energyplus?

I have created exterior overhangs, and I would like to turn them into exterior light shelves. I've tried searching the BCL and Sketchup for measures/user scripts, but have had no luck. I've also reviewed the E+ documentation, and have a general understanding of the "DaylightingDevice:Shelf" object and its fields. However, I am still fairly new to OS and E+, and I'm not very comfortable with using the IDF editor and switching back to OS. Is there a way to create the shelves in OS or the SketchUp plugin instead? I have found the "Daylighting Shelves" section under "Subsurfaces" on the "Spaces" tab in OS, but there are no objects in the library that I can drag into my model. Thanks!

drnnjhnsn

asked 2017-08-24 10:48:38 -0500

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Just out of interest, what exactly is an "exterior light shelf", as opposed to an "exterior overhang"?

rpg777 (2017-08-25 12:33:35 -0500) edit

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@drnnjhnsn There isn't a way to manually DaylightingDeviceShelf objects in the SketchUp Plugin or OpenStudio application but there is a surface method applyViewAndDaylightingGlassRatios that takes view and daylight window ratios and constructions, as well as an exterior shading projection factor and and interior shelf projection factor as arguments. In a measure it would look like this.

surface.applyViewAndDaylightingGlassRatios(viewWwrNS_s,daylightWwrS_s,sill,header,shadingProjectionFactor,lightShelfProjectionFactor,viewConstructionSouth.to_ConstructionBase,daylightConstructionSouth.to_ConstructionBase)

It is used in the School and Office AEDG Fenestration and Daylighting Controls Measures on BCL.

Once a DaylightingDeviceShelf has been added by a measure, you can see the interior partition surface that is used as the light shelf in the SketchUp Plugin, and you can the DaylightingDeviceShelf object in the Subsurfaces sub-tab in the OpenStudio application. You can re-assign a different interior partition surface to the light shelf object, or you can manually alter the existing surface or the construction assigned to it.

image description
View of interior partition surface assigned to DaylightingDeviceShelf after running applyViewAndDaylightingGlassRatios

image description
View of OpenStudio application subsurfaces sub-tab after DaylightingDeviceShelf has been added.

As a note, the "Library" has template objects that can be dragged into a model for Shading Controls and Frame and Divider, but not for DaylightingDevice Shelf.

It is a bit in the weeds, but the reason DaylightingDeviceShelf wasn't added to the Library is that the object can't exist without also having a SubSurface, and the SubSurface can't be re-assigned later on. It is possible this functionality could be added on the future, but I'm not aware of any plans. It would be pretty easy to write a simple measure to use in "Apply Measures Now" that takes a specific sub-surface, or construction, or maybe string search for the sub-surface name, to batch add light shelfs to the model for a subset of existing windows.