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Daylight control

asked 2015-01-20 12:29:37 -0500

Antop's avatar

updated 2015-08-10 03:47:20 -0500

Please, look at the picture attached. Sketchup model

The model has 5 thermal zones. Currently, the 4 external ones have exterior window. The central zone has no window. The sizes of the model are (72 x72) m2 The internal zone has 3900 mq more or less.

I would like to place a daylight controls within the central zone. I would like to calculate the light energy consumption.

The questions are:

  1. For these dimensions how many daylight controls do I have to place?
  2. Do I have to do a division in smaller zones?
  3. To allow the daylight passage through the internal wall, which features do internal walls have? I thought to consider them as a glazed wall. is it right ?

If you have other suggestion for me, please share it

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Question: Did you use air walls to separate your core and perimeter zones?

ljbrackney's avatar ljbrackney  ( 2015-01-20 14:30:57 -0500 )edit

No. I am using internal wall

Antop's avatar Antop  ( 2015-01-21 05:12:12 -0500 )edit

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answered 2015-01-20 21:11:52 -0500

Hi @Antop with the size of your model it is likely that the interior core of your building won't receive sufficient daylight without top lighting (skylights). If you only want to study daylighting controls in your perimeter zones then a daylighting point in each perimeter zone is probably sufficient. There are a few things to note:

  • If you are using EnergyPlus's daylighting engine then you do need to create and match interior windows between the perimeter and core zones, OpenStudio does not pass light through air walls when simulated with EnergyPlus
  • If you are using Radiance for the daylighting engine then light will pass through the air walls. However, the distribution of light in the core of the building will be poor without top lights. You can use illuminance maps in each zone to study the distribution of daylighting in each zone. You can view the illuminance map data using ResultsViewer to see which points in the space are most appropriate for daylighting controls.
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thank you. I will use EnergyPlus's daylighting engine with just one daylighting control placed in the center of core space and create interior windows (as you suggest).

This study case is part of a large experiment. There are other model also with more storeys, so i can't use skylights.

I just need to calculate the reduction of light energy consumption due to daylighting, even if it is very little. What you think about? How can I see the results from daylighting control?

Antop's avatar Antop  ( 2015-01-21 09:48:29 -0500 )edit

You will see the results of daylighting in reduced lighting energy in the annual tabular results. You can also look at illuminance map data or timeseries from the daylighting control using ResultsViewer to see more detail about the available daylighting.

macumber's avatar macumber  ( 2015-01-21 10:40:43 -0500 )edit

I am sorry, I can't find the "annual tabular results" Please, could you show me where to find it? If I use a daylighting control, do I have to set other parameters in energyplus? thanks

Antop's avatar Antop  ( 2015-01-23 06:10:01 -0500 )edit

The annual tabular results can be found on the Results Tab of the OpenStudio Application after a successful simulation. It's the last tab on the left side of the applicaiton interface; you'll see a couple of plots at the top for electricity and natural gas consumption, and if you scroll down you'll see tables of the same data.

rpg777's avatar rpg777  ( 2015-01-23 10:37:52 -0500 )edit

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Asked: 2015-01-20 12:29:37 -0500

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Last updated: Aug 10 '15