Illuminance Map

radiance-openstudio
1

Hi All

In EnergyPlus , by the use of “ Daylighting:Controls “, daylighting illuminance levels are calculated and then used to determine how much the electric lighting can be reduced.

Estimating daylight will not be affected by the size of illuminance map. However, by the use of radiance I noticed that Illuminance map size will have an effect on the results of the energy consumption of a building (Energy Per Conditioned Building Area). I did not understand why the illuminance map will affect such results ….

Thanks all

Khalid

2

Hi Khalid,

Nope, size of the illuminance map should not affect the reported energy savings. The savings in the latest OpenStudio versions are based on the illuminance at the daylighting control point, and of course the setpoint.

What version of OpenStudio are you using? I am happy to look at your model and your test process so we can see what's going on there. I'm on vacation this week but have access to email, just sporadically. Let me know how I can help!

Rob

Rob Guglielmetti
NREL Commercial Buildings Research Group
Golden, CO 80401
[email protected]

···

-----Original Message-----
From: Khalid [[email protected]<mailto:[email protected]>]
Sent: Tuesday, March 26, 2013 03:13 PM Mountain Standard Time
To: 'Discussion of Radiance with OpenStudio'
Subject: [Radiance-openstudio] Illuminance Map

Hi All
In EnergyPlus , by the use of “ Daylighting:Controls “, daylighting illuminance levels are calculated and then used to determine how much the electric lighting can be reduced.
Estimating daylight will not be affected by the size of illuminance map. However, by the use of radiance I noticed that Illuminance map size will have an effect on the results of the energy consumption of a building (Energy Per Conditioned Building Area). I did not understand why the illuminance map will affect such results ….

Thanks all

Khalid

3

Thanks Rob,

I think I’m not opening the right results files … the first result will come from this location: … /AppData/Local/Temp/qt_temp.gg4416/radout

… I did run several models by using Openstudio 10.3 … but for some reasons, the folder: “0-Ruby” disappear from the ‘Run’ folder ….

I do not knew why when opening the results from the result viewer in openstudio .. I did not get the results directly from the same folder of the model.

One more question Rob, is it possible now to run Radiance for a selected period of the year, or not yet. …..Thanks

Khalid

···

From: Guglielmetti, Robert [mailto:[email protected]]
Sent: 27 March 2013 18:07
To: 'Discussion of Radiance with OpenStudio'
Subject: Re: [Radiance-openstudio] Illuminance Map

Hi Khalid,

Nope, size of the illuminance map should not affect the reported energy savings. The savings in the latest OpenStudio versions are based on the illuminance at the daylighting control point, and of course the setpoint.

What version of OpenStudio are you using? I am happy to look at your model and your test process so we can see what's going on there. I'm on vacation this week but have access to email, just sporadically. Let me know how I can help!

Rob

Rob Guglielmetti
NREL Commercial Buildings Research Group
Golden, CO 80401
[email protected]

-----Original Message-----
From: Khalid [[email protected]]
Sent: Tuesday, March 26, 2013 03:13 PM Mountain Standard Time
To: 'Discussion of Radiance with OpenStudio'
Subject: [Radiance-openstudio] Illuminance Map

Hi All

In EnergyPlus , by the use of “ Daylighting:Controls “, daylighting illuminance levels are calculated and then used to determine how much the electric lighting can be reduced.

Estimating daylight will not be affected by the size of illuminance map. However, by the use of radiance I noticed that Illuminance map size will have an effect on the results of the energy consumption of a building (Energy Per Conditioned Building Area). I did not understand why the illuminance map will affect such results ….

Thanks all

Khalid