Outputs

Upon completion of the ERI calculation, summary output files and simulation files are available. See the sample_results directory for examples of these outputs.

Summary Files

Several summary files described below are found in the results directory.

ERI_Results.csv

The ERI_Results.csv file includes the ERI result as well as the high-level components (e.g., REUL, EC_r, EC_x, IAD_Save) that comprise the ERI calculation. The file reflects the format of the Results tab of the HERS Method Test spreadsheet.

Note that multiple comma-separated values will be reported for many of these outputs if there are multiple heating, cooling, or hot water systems.

See the example ERI_Results.csv.

ERI_Worksheet.csv

The ERI_Worksheet.csv file includes more detailed components that feed into the ERI_Results.csv values. The file reflects the formate of the Worksheet tab of the HERS Method Test spreadsheet.

Note that multiple comma-separated values will be reported for many of these outputs if there are multiple heating, cooling, or hot water systems.

See the example ERI_Worksheet.csv.

ERI______Home.csv

A CSV file is written for each of the homes simulated (e.g., ERIReferenceHome.csv for the Reference home). The CSV file includes the following sections of output.

See the example ERIRatedHome.csv.

Annual Energy Consumption by Fuel Type

Current fuel types are:

Type Notes
Electricity: Total (MBtu)  
Electricity: Net (MBtu) Excludes any PV generation.
Natural Gas: Total (MBtu)  
Fuel Oil: Total (MBtu)  
Propane: Total (MBtu)  
Wood: Total (MBtu) Currently unused for ERI.
Wood Pellets: Total (MBtu) Currently unused for ERI.

Annual Energy Consumption By Fuel Type and End Use

Current end use/fuel type combinations are:

Type Notes
Electricity: Heating (MBtu)  
Electricity: Heating Fans/Pumps (MBtu)  
Electricity: Cooling (MBtu)  
Electricity: Cooling Fans/Pumps (MBtu)  
Electricity: Hot Water (MBtu)  
Electricity: Hot Water Recirc Pump (MBtu)  
Electricity: Hot Water Solar Thermal Pump (MBtu)  
Electricity: Lighting Interior (MBtu)  
Electricity: Lighting Garage (MBtu)  
Electricity: Lighting Exterior (MBtu)  
Electricity: Mech Vent (MBtu)  
Electricity: Mech Vent Preheating (MBtu) Shared ventilation preconditioning system.
Electricity: Mech Vent Precooling (MBtu) Shared ventilation preconditioning system.
Electricity: Whole House Fan (MBtu)  
Electricity: Refrigerator (MBtu)  
Electricity: Dehumidifier (MBtu)  
Electricity: Dishwasher (MBtu)  
Electricity: Clothes Washer (MBtu)  
Electricity: Clothes Dryer (MBtu)  
Electricity: Range/Oven (MBtu)  
Electricity: Ceiling Fan (MBtu)  
Electricity: Television (MBtu)  
Electricity: Plug Loads (MBtu)  
Electricity: PV (MBtu)  
Natural Gas: Heating (MBtu)  
Natural Gas: Hot Water (MBtu)  
Natural Gas: Clothes Dryer (MBtu)  
Natural Gas: Range/Oven (MBtu)  
Natural Gas: Mech Vent Preheating (MBtu) Shared ventilation preconditioning system.
Fuel Oil: Heating (MBtu)  
Fuel Oil: Hot Water (MBtu)  
Fuel Oil: Clothes Dryer (MBtu)  
Fuel Oil: Range/Oven (MBtu)  
Fuel Oil: Mech Vent Preheating (MBtu) Shared ventilation preconditioning system.
Propane: Heating (MBtu)  
Propane: Hot Water (MBtu)  
Propane: Clothes Dryer (MBtu)  
Propane: Range/Oven (MBtu)  
Propane: Mech Vent Preheating (MBtu) Shared ventilation preconditioning system.
Wood Cord: Heating (MBtu)  
Wood Cord: Hot Water (MBtu)  
Wood Cord: Clothes Dryer (MBtu)  
Wood Cord: Range/Oven (MBtu)  
Wood Cord: Mech Vent Preheating (MBtu) Shared ventilation preconditioning system.
Wood Pellets: Heating (MBtu)  
Wood Pellets: Hot Water (MBtu)  
Wood Pellets: Clothes Dryer (MBtu)  
Wood Pellets: Range/Oven (MBtu)  
Wood Pellets: Mech Vent Preheating (MBtu) Shared ventilation preconditioning system.

Annual Building Loads

Current annual building loads are:

Type Notes
Load: Heating (MBtu) Includes HVAC distribution losses.
Load: Cooling (MBtu) Includes HVAC distribution losses.
Load: Hot Water: Delivered (MBtu) Includes contributions by desuperheaters or solar thermal systems.
Load: Hot Water: Tank Losses (MBtu)  
Load: Hot Water: Desuperheater (MBtu) Load served by the desuperheater.
Load: Hot Water: Solar Thermal (MBtu) Load served by the solar thermal system.

Annual Unmet Building Loads

Current annual unmet building loads are:

Type Notes
Unmet Load: Heating (MBtu)  
Unmet Load: Cooling (MBtu)  

These numbers reflect the amount of heating/cooling load that is not met by the HVAC system, indicating the degree to which the HVAC system is undersized. An HVAC system with sufficient capacity to perfectly maintain the thermostat setpoints will report an unmet load of zero.

Peak Building Electricity

Current peak building electricity outputs are:

Type Notes
Peak Electricity: Winter Total (W) Winter season defined by operation of the heating system.
Peak Electricity: Summer Total (W) Summer season defined by operation of the cooling system.

Peak Building Loads

Current peak building loads are:

Type Notes
Peak Load: Heating (kBtu) Includes HVAC distribution losses.
Peak Load: Cooling (kBtu) Includes HVAC distribution losses.

Annual Component Building Loads

Component loads represent the estimated contribution of different building components to the annual heating/cooling building loads. The sum of component loads for heating (or cooling) will roughly equal the annual heating (or cooling) building load reported above. Current component loads disaggregated by Heating/Cooling are:

Type Notes
Component Load: *: Roofs (MBtu) Heat gain/loss through HPXML Roof elements adjacent to conditioned space
Component Load: *: Ceilings (MBtu) Heat gain/loss through HPXML FrameFloor elements (inferred to be ceilings) adjacent to conditioned space
Component Load: *: Walls (MBtu) Heat gain/loss through HPXML Wall elements adjacent to conditioned space
Component Load: *: Rim Joists (MBtu) Heat gain/loss through HPXML RimJoist elements adjacent to conditioned space
Component Load: *: Foundation Walls (MBtu) Heat gain/loss through HPXML FoundationWall elements adjacent to conditioned space
Component Load: *: Doors (MBtu) Heat gain/loss through HPXML Door elements adjacent to conditioned space
Component Load: *: Windows (MBtu) Heat gain/loss through HPXML Window elements adjacent to conditioned space, including solar
Component Load: *: Skylights (MBtu) Heat gain/loss through HPXML Skylight elements adjacent to conditioned space, including solar
Component Load: *: Floors (MBtu) Heat gain/loss through HPXML FrameFloor elements (inferred to be floors) adjacent to conditioned space
Component Load: *: Slabs (MBtu) Heat gain/loss through HPXML Slab elements adjacent to conditioned space
Component Load: *: Internal Mass (MBtu) Heat gain/loss from internal mass (e.g., furniture, interior walls/floors) in conditioned space
Component Load: *: Infiltration (MBtu) Heat gain/loss from airflow induced by stack and wind effects
Component Load: *: Natural Ventilation (MBtu) Heat gain/loss from airflow through operable windows
Component Load: *: Mechanical Ventilation (MBtu) Heat gain/loss from airflow/fan energy from a whole house mechanical ventilation system
Component Load: *: Whole House Fan (MBtu) Heat gain/loss from airflow due to a whole house fan
Component Load: *: Ducts (MBtu) Heat gain/loss from conduction and leakage losses through supply/return ducts outside conditioned space
Component Load: *: Internal Gains (MBtu) Heat gain/loss from appliances, lighting, plug loads, water heater tank losses, etc. in the conditioned space

Annual Hot Water Uses

Current annual hot water uses are:

Type Notes
Hot Water: Clothes Washer (gal)  
Hot Water: Dishwasher (gal)  
Hot Water: Fixtures (gal) Showers and faucets.
Hot Water: Distribution Waste (gal)  

ERI______Home_Hourly.csv

See the Running section for requesting hourly outputs. When requested, a CSV file of hourly outputs is written for the Reference/Rated Homes (e.g., ERIReferenceHome_Hourly.csv for the Reference home).

Depending on the outputs requested, CSV files may include:

Type Notes
Fuel Consumptions Energy use for each fuel type (in kBtu for fossil fuels and kWh for electricity).
End Use Consumptions Energy use for each end use type (in kBtu for fossil fuels and kWh for electricity).
Hot Water Uses Water use for each end use type (in gallons).
Total Loads Heating and cooling loads (in kBtu) for the building.
Component Loads Heating and cooling loads (in kBtu) disaggregated by component (e.g., Walls, Windows, Infiltration, Ducts, etc.).
Zone Temperatures Average temperatures (in deg-F) for each space modeled (e.g., living space, attic, garage, basement, crawlspace, etc.).
Airflows Airflow rates (in cfm) for infiltration, mechanical ventilation, natural ventilation, and whole house fans.
Weather Weather file data including outdoor temperatures, relative humidity, wind speed, and solar.

See the example ERIRatedHome_Hourly.csv.

ERI______Home.xml

A HPXML file is written for each of the homes simulated (e.g., ERIReferenceHome.xml for the Reference home). The file reflects the configuration of the home after applying the ERI 301 ruleset.

See the example ERIRatedHome.xml.

Simulation Files

In addition, raw EnergyPlus simulation input/output files are available for each simulation (e.g., ERIRatedHome, ERIReferenceHome, etc. directories).

Warning

It is highly discouraged for software tools to read the raw EnergyPlus output files. The EnergyPlus input/output files are made available for inspection, but the outputs for certain situations can be misleading if one does not know how the model was created. If there are additional outputs of interest that are not available in our summary output files, please send us a request.

See the example ERIRatedHome directory.