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How to assign lighting loads by floor in OS?

asked 2016-10-11 15:34:02 -0500

Is there a way to assign lighting definitions in OpenStudio to an entire floor, rather than to a space type or to individual spaces? This would be really useful when using the building area method for lighting power densities where a lighting load is applied to an entire floor across multiple space types, and where other floors have other BAM lighting types. I would like to see a way on the spaces tab to apply a selected lighting definition to multiple space types, rather than have to duplicate space types for each floor level, or manually assign the lighting definitions to 100+ spaces.

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answered 2016-10-12 12:14:00 -0500

Are you using the building area method for lighting, but not for other internal loads and occupancy? If you were using building area method across all internal loads, you could just assign a space type to each Building Story. You would only need to do this if you had a different BAM value for each building story; otherwise you could just assign the space type for the building.

But if you are modeling occupancy and non-lighting internal loads by space type with many unique space types, and want BAM lighting the same across the building or story, you can take another approach. Multiple space types can refer to the same lighting definition. When you change that definition and it affects all space types using it. This would allow you to vary the BAM number easily if you wanted to.

As you mentioned, there is always the option of having space types with no lighting, and then applying lighting individually to each space. This would be a pretty easy measure to write that could be applied with "Apply Measures Now". would look something like this. You could add an argument for LPD for each building story.

model.getBuildingStories.each do |story|
  story.spaces.each do |space|

setLightingPowerPerFloorArea may be heavy handed. It will make space type unique if needed and remove any existing lights. It may work cleanly without altering space type assignments if the space type doesn't have any lights, but I have not tested that. If not you can have code loop through and remove lights and then add new ones. Either approach allows you to run this multiple times without stacking up too many lights in the space.

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The only load I would like to assign by floor type is lighting. People, plug loads, etc need to be assigned by space type. This is for a LEED mixed use building with a ground floor that is primarily retail, several garage floors with core spaces, and several office levels. So I would have lighting loads applied to entire floors based on their primary use according to ASHRAE 90.1-2007 lighting BAM guidelines, but the other loads would not be applied per floor.

kramerica's avatar kramerica  ( 2016-10-12 13:31:14 -0500 )edit

I think the measure would be really useful, unfortunately I haven't written any measures yet and don't know where to start with measure writing.

kramerica's avatar kramerica  ( 2016-10-12 13:35:44 -0500 )edit

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Asked: 2016-10-11 15:34:02 -0500

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Last updated: Oct 12 '16