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How can I get the hourly load cooling demands in the EP-Launch 8.7?

asked 2017-07-05 01:56:45 -0500

Esperanza's avatar

updated 2017-07-05 11:44:26 -0500

I am working with the EP-Launch 8.7. I want to see the variable load cooling demand in hourly basis by choosing Output:Meter/Electricity building. I am running the simulation after I have chosen the variable, but the output Meter in not available (Box appears grey). How can I access to this result? How can I active this box?

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answered 2017-07-05 11:43:56 -0500

Output:Meter objects are generally meant to track energy consumption across different categories, while Output:Variable objects are meant to track timestep values of parameters. I would recommend not using the Electricity:Building meter because it will show ALL electricity use for the entire building (lights, receptacles, HVAC, etc.), which won't be helpful to determine cooling demand. You can use the Zone Predicted Sensible Load to Cooling Setpoint Heat Transfer Rate Output:Variable for a thermostat object, and sum all the zone loads together for building demand. Or, you can find the appropriate Output:Variable object related to cooling load provided from the HVAC system you're simulating.

If you are trying to add an Output:Meter object, then you need to select "Output:Meter" in the Class List on the left of IDF Editor first, and then click on the "New Obj" button to add that type of object. Output:Variable objects must match an item from the list shown in the X.RDD output file. If added to the IDF correctly, they will appear in the X.CSV file, linked to the "Variables" button in EP-Launch. Output:Meter objects must match an item from the list shown in the X.MDD output file. If added to the IDF correctly, they will appear in the same X.CSV file as well as a different XMeter.CSV file, linked to the "Meters" button in EP-Launch.

If the "Meters" button is still gray in EP-Launch, you have not correctly added an Output:Meter object. If you examine the EnergyPlus error file named X.err (linked to the "Errors" button in EP-Launch), there will likely be a message similar to this:

 ** Warning ** Output:Meter: invalid Name="BAD NAME" - not found.

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Adding an Output:Meter in IDF Editor

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"Meters" and "Variables" buttons in EP-Launch

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I have selected the object class and the output meter as you indicated @aaron. Still appear a grey box in the meters. How do you exactly mean when you say adding an output. It is supposed if I add object class and output meter in the editor automatically the box is actived in the EP-launch? Thanks a lot!

Esperanza's avatar Esperanza  ( 2017-07-05 12:00:43 -0500 )edit

image description

Esperanza's avatar Esperanza  ( 2017-07-05 12:04:14 -0500 )edit

After adding the Output:Meter object, you will need to save your IDF and run EnergyPlus a second time. Then, the meter CSV file will be created.

Aaron Boranian's avatar Aaron Boranian  ( 2017-07-05 13:11:07 -0500 )edit

@aaron thank you! Now, it is working. I just was forgetting save the IDF.

Esperanza's avatar Esperanza  ( 2017-07-06 02:22:03 -0500 )edit

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Asked: 2017-07-05 01:56:45 -0500

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Last updated: Jul 05 '17