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daylighting and energy plus

asked 2015-02-23 21:52:05 -0600

T.Galanos's avatar

Is it possible to simulate one cooling zone with multiple lighting zones, under different daylighting schedules?

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Gonna need a little more info on this one. Short answer is "yes" on the multiple lighting zones piece, but with caveats. Not sure what yo mean by "different daylighting schedules", though. Could you give us a little more detail on what you're trying to do?

rpg777's avatar rpg777  ( 2015-02-24 09:01:02 -0600 )edit

Hey Rpg777,

Sorry I thought I'd be laconic my first time here. Workflow is this:

First, I am using Honeybee, with the help of daysim and radiance, to do rough daylight calculations for a zone (open office type), although it can be any type or number of zones. Second, I analyze the results and I select only the fraction of the floor area that is above 3.5% Daylight Factor. That is my daylight zone. Third, I refine the daylight calculations in the daylight zone. I then use those results to create a lighting profile through Daysim. I then input this profile as a lighting schedule for my zone.

T.Galanos's avatar T.Galanos  ( 2015-02-24 19:50:09 -0600 )edit

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answered 2015-02-24 09:49:03 -0600

The Daylighting:Controls object in EnergyPlus allows two different reference points to be used within a zone and the fraction of the total zone lighting that is controlled by each reference point and each reference point can have different illuminance setpoints. This allows some of the flexibility you may be looking for but the two reference points must be controlled the same way (continuous or stepped or continuous/off) and both share the same glare controls as well as the same schedule for what times of the day or year that daylighting controls are active (usually all the time anyway). A second option in EnergyPlus to do daylighting is available with the DElight daylighting objects which allows more reference points but it comes with several limitations described in the InputOutputReference that you should review before trying them.

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Thanks Jason. I must admit I don't really have deep understanding of EnergyPlus workings. I will look into both options you mentioned. It looks as if EnergyPlus can allow me to do what I want, at least for 2 'zones'.

T.Galanos's avatar T.Galanos  ( 2015-02-24 19:51:57 -0600 )edit

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Asked: 2015-02-23 21:52:05 -0600

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Last updated: Feb 24 '15