Electricity:HVAC accounts for all HVAC electric consumption? How to obtain Chiller's consumption?

asked 2021-09-04 19:46:50 -0500

Miguel's avatar

Hello! I'm trying to perform a model calibration. For that I have to try that Measured Electricity Consumption data that was given to me matches the Simulated energy consumption of EnergyPlus. Specifically for this case, I'm trying to approximate measured and simulated HVAC electric energy consumption, since I have data of HVAC measured consumption too. I have 2 questions regarding this issue.

1) The first one is that I'm not sure of what electricity is assigned to Electricity:HVAC in EnergyPlus meter. I made a research in MTD file and saw that, for example, chiller, cooling tower, or exhaust and intake ventilation do not make part of Electricity:HVAC in meter. That way, the simulated HVAC electric consumption is much smaller than the measured. What is the reason for these components (chiller, cooling tower, intake and exhaust ventilation consumptions) do not make part of Electricity:HVAC meter?

2) The second question is: in that case I tried to sum the energy consumption of Electricity:HVAC to the components that were not included. However, I noticed I couldn't obtain the isolated consumption of chillers for example. In meter, chillers' electric consumption is together with other consumptions, in Cooling:Electricity I think. But I only want chillers' consumption separated from the rest. How can I obtain it?


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1) I believe HVAC is only Zone HVAC consumption. 2) I would look into a Custom Meter and only assign the chiller to it.

mattkoch's avatar mattkoch  ( 2021-09-06 06:35:19 -0500 )edit

Hello! Thank you for the help. Regarding the 2 questions: 1) What do you mean by only Zone HVAC consumption? Sorry but I don't know if I completely understand the definition. 2) I tried to do that. I've done this:

Name: Chillers Meter Fuel Type:Electricity Output Variable or Meter Name 1: Chiller Electric Energy

But I don't know how I can see the results of the hourly meter of electricity consumption of chillers I want.

Miguel's avatar Miguel  ( 2021-09-06 10:24:25 -0500 )edit

1) There is HVAC equipment that only serves a single zone, such as a fan coil unit, and there is equipment that serves multiple zones, such as an air handling unit or a chiller. I believe HVAC electricity only covers the power/energy of the fan coil unit‘s fan. 2) I am using OpenStudio measures. It has a report that shows much of what EnergyPlus produces. Among that is a custom meter table with the results. You may also have to add an Output:Table/Monthly for the Meter:Custom if you are using EnergyPlus straight up. It has been a while since I dealt with this.

mattkoch's avatar mattkoch  ( 2021-09-06 10:54:46 -0500 )edit

Meter:Custom, MeterName, Electricity, CH-1, Chiller Electric Energy;

Output:Meter, MeterName, Monthly;

Output:Table:Monthly, TableName, 3, MeterName, SumOrAverage, MeterName, Maximum;

The Output:Meter in the middle may not be required. The SumOrAverage gives monthly kWh, the Maximum gives monthly peak kW. Make sure Chiller Electric Energy exists in the .rdd file, too.

mattkoch's avatar mattkoch  ( 2021-09-06 11:12:34 -0500 )edit

Thanks, it worked! Chillers consumption is now accounted in meters. Regarding question 1), I understand your point and I appreciate the help. Still, exhaust and intake ventilation are zoned and are not accounted in Electricity:HVAC for example and AHU consumption is accounted.

Miguel's avatar Miguel  ( 2021-09-07 08:42:33 -0500 )edit