Question-and-Answer Resource for the Building Energy Modeling Community
Get started with the Help page

# Meaning of Zone Energy Transfer in Meter Output?

Can anyone help me interpret the following item of Energyplus meter outputs in mdd?

Output:Meter,Heating:EnergyTransfer:Zone.

Can this be understood as an amount of actual energy delivery from HVAC to a thermal zone?

edit retag close merge delete

Sort by » oldest newest most voted

The short answer is yes. The long answer is that "energy transfer" data is organized on system, zone, facility, building, heating, or cooling meters.

Energy transfer meters refer to air or water energy transfer. The electric meters report electrical energy use. Meters used in a simulation are listed in the meter file (mdd). Each meter is described in more detail in the meter definition file (mtd). At the top of the mtd file is a list of all energy and electricity report variables and on which meters those variables are reported. For example one energy transfer variable shows the multiple meters where this energy data is stored:

 Meters for 306,SPACE1-1:Zone Air System Sensible Heating Energy [J]
OnMeter=EnergyTransfer:Facility [J]
OnMeter=EnergyTransfer:Building [J]
OnMeter=EnergyTransfer:Zone:SPACE1-1 [J]
OnMeter=Heating:EnergyTransfer [J]
OnMeter=Heating:EnergyTransfer:Zone:SPACE1-1 [J]


In the above example, the Zone Air System Sensible Heating Energy is included on meter=Heating:EnergyTransfer as well as four other meters. One could infer that all zones would be included on the same heating energy transfer meter and finding this specific meter in the mtd shows that the Heating:EnergyTransfer meter contains information for each zone.

 For Meter=Heating:EnergyTransfer [J], ResourceType=EnergyTransfer, EndUse=Heating, contents are:
PLENUM-1:Zone Air System Sensible Heating Energy
SPACE1-1:Zone Air System Sensible Heating Energy
SPACE2-1:Zone Air System Sensible Heating Energy
SPACE3-1:Zone Air System Sensible Heating Energy
SPACE4-1:Zone Air System Sensible Heating Energy
SPACE5-1:Zone Air System Sensible Heating Energy


All energy data contained on a single meter is summarized at the bottom of the file. In this example, the energy transfer data for SPACE1-1:

 For Meter=EnergyTransfer:Zone:SPACE1-1 [J], ResourceType=EnergyTransfer, Group=Zone, contents are:
SPACE1-1:Zone Air System Sensible Heating Energy
SPACE1-1:Zone Air System Sensible Cooling Energy

For Meter=Heating:EnergyTransfer:Zone:SPACE1-1 [J], ResourceType=EnergyTransfer, EndUse=Heating, Group=Zone, contents are:
SPACE1-1:Zone Air System Sensible Heating Energy

For Meter=Cooling:EnergyTransfer:Zone:SPACE1-1 [J], ResourceType=EnergyTransfer, EndUse=Cooling, Group=Zone, contents are:
SPACE1-1:Zone Air System Sensible Cooling Energy


From the Input Output Reference document:

"Zone Air System Sensible Heating Energy [J]

This output variable represents the sensible heating energy in Joules that is actually
supplied by the system to that zone for the timestep reported. This is the sensible
heating rate multiplied by the simulation timestep. This is calculated and reported
from the Correct step in the Zone Predictor-Corrector module. This field is not
multiplied by zone or group multipliers. Zone Air System Sensible Heating (and
Cooling) Energy (and Rate) all report the heating or cooling delivered by the HVAC
system to a zone. These values are calculated by multiplying the supply air mass
flow rate by the difference between the supply air temperature and the zone air
temperature. This does not always indicate the operation of heating or cooling coils.
For example, cooling will be reported if the supply air is cooled due to the introduction
of outside air, even ...
more

## Stats

Seen: 782 times

Last updated: Oct 24 '17