At the end of an EnergyPlus simulation DesignBuilder reads the EnergyPlus output file eplusout.eso. The format of this file is described in EnergyPlus documentation. The table below explains how the raw EnergyPlus output is processed to create DesignBuilder output. The Environmental/Comfort Output column refers to the data shown in DesignBuilder output screens. EnergyPlus Report variable column data shows report variable names with the units in square brackets. The units should be omitted when using the report variables in IDF data. The Area column indicates the zone, surface, component etc.
Environmental/Comfort Output |
EnergyPlus Report Variable |
Area |
Notes* |
Internal air temperature |
Zone Mean Air Temperature [C] |
ZoneId |
|
Internal radiant temperature |
Zone Mean Radiant Temperature [C] |
ZoneId |
|
Internal operative temperature |
|
ZoneId |
0.5 x (Zone Mean Air Temperature + Zone Mean Radiant Temperature) |
Relative Humidity |
Zone Air Relative Humidity [%] |
ZoneId |
|
Fanger PMV |
FangerPMV |
PEOPLE ZoneId |
|
Pierce PMV ET |
PiercePMVET |
PEOPLE ZoneId |
|
Pierce PMV SET |
PiercePMVSET |
PEOPLE ZoneId |
|
Pierce Discomfort Index (DISC) |
PierceDISC |
PEOPLE ZoneId |
|
Pierce Thermal Sens. Index (TSENS) |
PierceTSENS |
PEOPLE ZoneId |
|
Kansas Uni TSV |
KsuTSV |
PEOPLE ZoneId |
|
Discomfort hrs (summer clothing) |
Time Not Comfortable Summer Clothes [hr] |
PEOPLE ZoneId |
|
Discomfort hrs (winter clothing) |
Time Not Comfortable Winter Clothes [hr] |
PEOPLE ZoneId |
|
Discomfort hrs (all clothing) |
Time Not Comfortable Summer or Winter Clothes [hr] |
PEOPLE ZoneId |
|
Fabric and ventilation |
|||
Glazing heat gain |
Window Heat Gain [W] - Window Heat Loss [W] - Window Transmitted Solar [W] |
SurfaceId |
Window Transmitted Solar is subtracted so that Glazing heat gain represents the transfer of all heat through the window excluding beam and diffuse short-wave solar heat effects. This makes it more comparable with the opaque surface conduction results.
NB The subtraction of solar from glazing heat gain is done as a post process on the output results and does not affect the simulation itself. |
Walls, Roofs, Ceilings (int), Floors (int), Floors (ext), Ground floors, Partitions (int), Doors and vents |
Opaque Surface Inside Face Conduction [W] |
SurfaceId |
|
External infiltration |
Zone Infiltration Sensible Heat Loss [J] + Zone Infiltration Sensible Heat Gain [J] |
ZoneId |
Scheduled Natural ventilation only
|
External natural ventilation |
Zone Ventilation Sensible Heat Gain [J] + Zone Ventilation Sensible Heat Loss [J] |
ZoneId |
Scheduled Natural ventilation only |
External mechanical ventilation |
Zone Ventilation Sensible Heat Gain [J] + Zone Ventilation Sensible Heat Loss [J] |
ZoneId |
Scheduled Natural ventilation only
|
Internal Air |
AirflowNetwork Mixing Sensible Loss Rate [W] + AirflowNetwork Mixing Sensible Gain Rate [W] |
ZoneId |
Calculated Natural ventilation only |
External Air |
AirflowNetwork Infiltration Sensible Loss Rate [W]+ AirflowNetwork Infiltration Sensible Gain Rate [W] |
ZoneId |
Calculated Natural ventilation only |
Airflow |
|||
Mech Vent + Nat Vent + Infiltration |
Zone Mechanical Ventilation Air Change Rate [ach] |
ZoneId |
Summed across blocks and building using volume-weighted average |
Mech Vent + Nat Vent + Infiltration |
Zone Ventilation Air Change Rate [ach] |
ZoneId |
Summed across blocks and building using volume-weighted average |
Mech Vent + Nat Vent + Infiltration |
Zone Infiltration Air Change Rate [ach] |
ZoneId |
Summed across blocks and building using volume-weighted average |
Internal Gains |
|||
Task lighting gains |
ELECTRIC EQUIPMENT#ZoneId#TaskLights* [J] |
- |
|
General lighting gains |
ELECTRIC EQUIPMENT#ZoneId#GeneralLights* [J] |
- |
The 'GeneralLights' ELECTRIC EQUIPMENT EnergyPlus output is a lighting fuel consumption and is summed to give the Lighting fuel consumption (below). The gain to the zone is calculated from this in each zone by multiplying by (1 - Return air fraction). |
Miscellaneous gains |
ELECTRIC EQUIPMENT#ZoneId#02:InteriorEquipment* [J] |
- |
The '02' ELECTRIC EQUIPMENT EnergyPlus output is the miscellaneous internal gains fuel consumption and is summed to give the Room fuel consumption (below). The gain to the zone is calculated from this in each zone by multiplying by (1 - Fraction lost). |
Process gains |
ELECTRIC EQUIPMENT#ZoneId#03:InteriorEquipment* [J] |
- |
The '03' ELECTRIC EQUIPMENT EnergyPlus output is the process internal gains fuel consumption and is summed to give the Room fuel consumption (below). The gain to the zone is calculated from this in each zone by multiplying by (1 - Fraction lost). |
Catering gains |
ELECTRIC EQUIPMENT#ZoneId#04:InteriorEquipment* [J] |
- |
The '04' ELECTRIC EQUIPMENT EnergyPlus output is the catering internal gains fuel consumption and is summed to give the Room fuel consumption (below). The gain to the zone is calculated from this in each zone by multiplying by (1 - Fraction lost). |
Computer and equipment gains |
ELECTRIC EQUIPMENT#ZoneId#05:InteriorEquipment* [J] |
- |
|
Occupancy gains |
Zone People Sensible Heat Gain [J] |
ZoneId |
|
Solar Gains Exterior Windows |
Zone Transmitted Solar [W] |
ZoneId |
|
Solar Gains Interior Windows |
Zone Diff Solar from Interior Windows [W] + Zone Beam Solar from Interior Windows [W] |
ZoneId |
|
Zone Sensible Cooling |
Zone/Sys Sensible Cooling Rate [W] |
ZoneId |
Cooling energy to the zone from the HVAC system (not energy consumption) |
Zone Sensible Heating |
Zone/Sys Sensible Heating Rate [W] |
ZoneId |
Heating energy to the zone from the HVAC system (not energy consumption) |
System Heat Flows |
|||
Zone Heating |
Total Water Heating Coil Rate [W] |
ZoneId REHEAT COIL |
VAV/CAV Hot water reheat coils |
Zone Heating |
Heating Coil Rate [W] |
ZoneId REHEAT COIL |
VAV/CAV Electric reheat coils |
Zone Heating |
Heating Coil Rate [W] |
ZoneId AHU HEATING COIL |
Unitary single zone |
Zone Heating |
Total Water Heating Coil Rate [W] |
ZoneId HEATING COIL |
Fan coil |
Preheat |
Heating Coil Rate [W] |
AHU PREHEAT COIL |
VAV/CAV Gas/Electric preheat coils |
AHU Heating |
Total Water Heating Coil Rate [W] |
AHU HEATING COIL |
VAV/CAV Hot water coils |
AHU Heating |
Heating Coil Rate [W] |
AHU HEATING COIL |
VAV/CAV with Gas/Electric AHU heating coils and Unitary multizone |
Total Cooling |
Purchased Air Total Cooling Rate [W] |
ZONE ZoneId PURCHASED AIR |
Simple HVAC convective and ASHRAE Cooling design |
Total Cooling |
Total Water Cooling Coil Rate [W] |
AHU COOLING COIL |
VAV/CAV with Chilled water coils |
Total Cooling |
DX Coil Total Cooling Rate [W] |
AHU COOLING COIL |
Unitary Multizone |
Total Cooling |
DX Coil Total Cooling Rate [W] |
ZoneId AHU COOLING COIL |
Unitary single zone |
Total Cooling |
Total Water Cooling Coil Rate [W] |
ZoneId COOLING COIL |
Fan coil |
Sensible Cooling |
Purchased Air Sensible Cooling Rate [W] |
ZONE ZoneId PURCHASED AIR |
Simple HVAC convective and ASHRAE Cooling design |
Sensible Cooling |
Sensible Water Cooling Coil Rate [W] |
AHU COOLING COIL |
VAV/CAV with Chiller water |
Sensible Cooling |
DX Coil Sensible Cooling Rate [W] |
AHU COOLING COIL |
Unitary multizone |
Sensible Cooling |
DX Coil Sensible Cooling Rate [W] |
ZoneId AHU COOLING COIL |
Unitary single zone |
Sensible Cooling |
Sensible Water Cooling Coil Rate [W] |
ZoneId COOLING COIL |
Fan coil |
Fuel breakdown (building level) |
|||
Heat generator |
|
Compact HVAC |
The fuel consumption for each heating load is calculated based on the efficiency of the heat generation and distribution loss:
Heat generator fuel = (Heating Load x Heating distribution loss factor) / Heat generator CoP
Where:
Heating distribution loss factor = 1 + (Heating Distribution Loss) / 100
Note 1: distribution loss is 0 for direct electric and gas heating coils. Note 2: CoP for direct gas coils is assumed to be 0.8 and direct electric coils 1.0. |
Heat generator |
|
Simple HVAC |
Heat generator fuel = Heating load / Heating system CoP
Note: the Heating system CoP is defined separately for each zone. |
Chiller |
|
Compact HVAC |
The fuel consumption for each cooling load is calculated based on the efficiency of the chiller and distribution loss:
Chiller fuel = (Cooling Load x Cooling distribution loss factor) / Chiller CoP
Where:
Cooling distribution loss factor = 1 + (Cooling Distribution Loss) / 100 |
Chiller |
|
Simple HVAC |
Chiller fuel = Cooling load / Cooling system CoP
Note: the Cooling system CoP is defined separately for each zone. |
System fan |
Fan Electric Consumption [J] |
AHU SUPPLY FAN |
VAV/CAV with Chiller water, Unitary multizone |
System fan |
Fan Electric Consumption [J] |
ZoneId AHU SUPPLY FAN |
Unitary single zone |
System fan |
Fan Electric Consumption [J] |
ZoneId SUPPLY FAN |
Fan coil |
System pumps |
Pump Electric Consumption [J] |
HOT WATER LOOP HW SUPPLY PUMP + CHILLED WATER LOOP CHW SUPPLY PUMP + CHILLED WATER LOOP CNDW SUPPLY PUMP |
|
DHW |
Domestic Hot Water Consumption [m3] |
ZoneId DHW 1 |
DHW energy (kWh) = 1000 (kg/m3) x 4.187 (KJ/kg-K) x (Domestic Hot Water Consumption [m3]) x (Delivery water temperature - Mains water temperature) / DHW CoP
Where:
DHW CoP is Heat generator CoP when using 1-Central heating boiler DHW type. |
Preheat energy |
|
|
(Preheat Heating Coil Rate + Distr loss if appropriate) / Preheat CoP |
Lighting |
|
|
|
Room electricity |
|
|
|
Room gas |
|
|
|
Room oil |
|
|
|
Room solid |
|
|
|
Room bottled gas |
|
|
|
Room other |
|
|
|
Fuel totals (building level) |
|||
Electricity |
|
|
1-Electricity from grid |
Gas |
|
|
2-Natural gas |
Oil |
|
|
3-Oil |
Solid |
|
|
4-Coal + 7-Anthracite + 8-Smokeless fuel (including coke) |
Bottled gas |
|
|
5-LPG + 6-Biogas |
Other fuel consumption |
|
|
9-Dual fuel appliances (mineral + wood) + 10-Biomass + 11-Waste heat |
CO2 production (building level) |
|||
CO2 |
|
|
Calculated from Fuel totals above using locally published CO2 emission factors from the Emissions tab on the Legislative regions dialog accessed from the Site level on the Regions model data tab. |
Site Weather data |
|||
Outside dry-bulb temperature |
Outdoor Dry Bulb |
Simulation: Direct from EPW - spot value,
Cooling design: Outdoor Dry Bulb - spot value. |
For Cooling design, value is initialised from user input before calculation is run but is updated with E+ value after the calculation. |
Outside dew-point temperature |
Outdoor Dew Point |
Simulation: Direct from EPW - spot value,
Cooling design: Outdoor Dew Point - spot value. |
|
Direct normal solar |
Direct Solar |
Simulation: Direct from EPW - preceding hour,
Cooling design: Direct Solar - preceding hour. |
|
Diffuse horizontal solar |
Diffuse Solar |
Simulation: Direct from EPW - preceding hour,
Cooling design: Diffuse Solar - preceding hour. |
|
Wind speed |
Wind Speed |
Simulation: Direct from EPW - spot value,
Cooling design: Wind Speed - preceding hour.
|
|
Wind direction |
Wind Direction |
Simulation: Direct from EPW - spot value,
Cooling design: Assumed wind is from North. |
|
Atmospheric pressure |
Outdoor Barometric Pressure |
Simulation: Direct from EPW - spot value,
Cooling design:Outdoor Barometric Pressure - preceding hour. |
Estimated from elevation before cooling design calc is run but E+ value used after calculation. |
Solar altitude |
Solar Altitude Angle |
Simulation: Calculated - spot value,
Cooling design:Solar Altitude Angle - preceding hour. |
For Cooling design, solar positions are initialised with calculated values before calculation is run but are updated with E+ values after the calculation. Calculated simulation data is based on 'spot values' on the hour so in this case the value for 12:00 is the value exactly at midday. |
Solar azimuth |
Solar Azimuth Angle |
Simulation: Calculated - spot value,
Cooling design:Solar Azimuth Angle - preceding hour. |
* Variables shown in green represent EnergyPlus output.
'Direct from EPW' means that the values in the hourly weather file itself are displayed.
EnergyPlus hourly output always represents totals and averages over the preceding hour so data for 12:00 is for the period 11:01 to 12:00.