New Features
WeatherStation/extension/EPWFilePath
is now optional; if not provided, the closest TMY3 weather station will be automatically selected based on the zip code.
Bugfixes
New Features
- Updates HERS test outputs to match the latest RESNET accreditation forms.
Bugfixes
- Fixes clothes washer configurations for ZERH v2 and ENERGY STAR SFNH 3.2/MFNC 1.2 programs when the rated home does not include a clothes washer.
New Features
- Updates to OpenStudio 3.9/EnergyPlus 24.2/HPXML v4.1-rc1.
- Adds 2024 IECC ERI pathway calculation.
- Breaking change: Renamed
Emissions: <EmissionsType>: RESNET: XXX
toEmissions: <EmissionsType>: ANSI301: XXX
in Annual Home CSV output files. - Implements ANSI/RESNET/ICC Standard 301-2022 Addendum E for CFIS systems.
ERICalculation/Version
andCO2IndexCalculation/Version
can now be "2022CE".- Breaking change: Removes
FanPower
/FanPowerDefaulted
andVentilationOnlyModeAirflowFraction
inputs for CFIS systems. - Breaking change: Adds
CFISControls/HasOutdoorAirControl
andCFISControls/extension/ControlType
inputs for CFIS systems. - Adds choice of "none" for
CFISControls/AdditionalRuntimeOperatingMode
input for CFIS systems. - Adds optional
CFISControls/extension/SupplementalFanRunsWithAirHandlerFan
input for CFIS systems.
- Adds inputs for modeling skylight curbs and/or shafts.
- Relaxes IECC climate zone requirements.
- IECC climate zone years other than 2006 are now always optional; for programs that use specific IECC climate zone years (e.g., 2021 for ZERH SF 2.0), that year is used if provided, otherwise the next earliest provided year will be used with the assumption that the climate zone has not changed across the years.
- See the documentation for more information.
- Updates HERS Diagnostic Output to v0.3.0.
Bugfixes
- Adds error-checking for
NumberofConditionedFloorsAboveGrade
=0, which is not allowed per the documentation. - Fixes error if a heating system and a heat pump (that only provides cooling) are attached to the same distribution system.
- Fixes double counting of battery storage losses in ERI calculation; CO2e Index is unaffected.
- Misc Manual J design load calculation improvements.
- Fixes GSHP rated fan/pump powers in net to gross calculations.
New Features
- Updates to OpenStudio 3.8, EnergyPlus 24.1, HPXML 4.0-rc4.
- Implements ANSI/RESNET/ICC Standard 301-2022 and Addendum C.
- Breaking change: For shared water heaters,
NumberofUnitsServed
is replaced byextension/NumberofBedroomsServed
. - Breaking change: For shared hot water recirculation systems,
NumberofUnitsServed
is replaced byNumberofBedroomsServed
. ERICalculation/Version
andCO2IndexCalculation/Version
can now be "2022C" or "2022".- Allows modeling electric battery storage, including shared batteries ("2022C" or newer).
- The
ElectricAuxiliaryEnergy
input for boilers is no longer used.
- Breaking change: For shared water heaters,
- Breaking change: ERI_Results.csv and ERI_Worksheet.csv combined into a single ERI_Results.csv that better reflects the current ERI calculation components; additional fields (e.g., PEfrac) added and a few renamed/removed.
- Breaking change: Skylights attached to roofs of attics (e.g., with shafts or sun tunnels) must include the
Skylight/AttachedToFloor
element. - Breaking change: Each
VentilationFan
must have one (and only one)UsedFor...
element set to true. - HERS software tests:
- HERS Hot Water test HPXMLs have been updated to be direct EnergyPlus simulations (like the HERS HVAC & DSE tests already were); they are no longer run through ERI simulations.
- HERS HVAC DSE tests now use duct effective R-values instead of nominal insulation R-values to demonstrate that they pass RESNET acceptance criteria.
- Adds
--diagnostic-output
commandline argument to produce a diagnostic output file per the HERS Diagnostic Output Schema. - Allows
AverageCeilingHeight
to be optionally provided for infiltration calculations. - Allows
Roof/RadiantBarrier
to be omitted; defaults to false. - Allows
FractionDuctArea
as alternative toDuctSurfaceArea
- Allows alternative
LabelEnergyUse
(W) input for ceiling fans. - Allows
Slab/extension/GapInsulationRValue
input for cases where a slab has horizontal (under slab) insulation. - Ground source heat pump model enhancements.
- Improves heating/cooling component loads.
- Now defaults to -20F for
CompressorLockoutTemperature
for variable-speed air-to-air heat pumps. - Adds more error-checking for inappropriate inputs (e.g., HVAC SHR=0 or clothes washer IMEF=0).
- Clarifies that HVAC
Capacity=-1
can be used to autosize HVAC equipment for research purposes or to run tests. It should not be used for a real home, and a warning will be issued when it's used.
Bugfixes
- Fixes incorrect Reference Home mechanical ventilation flowrate for attached units (when Aext is not 1).
- Fixes possible 301ruleset.rb error due to floating point arithmetic.
Bugfixes
- Fixes emissions lookup when zip code starts with a zero.
New Features
- Updates to OpenStudio 3.7.0/EnergyPlus 23.2.
- Breaking change: Updates to HPXML v4.0-rc2:
- HPXML namespace changed from http://hpxmlonline.com/2019/10 to http://hpxmlonline.com/2023/09.
- Replaces "living space" with "conditioned space", which better represents what is modeled.
- Replaces
PortableHeater
andFixedHeater
withSpaceHeater
.
- HVAC updates:
- Updated assumptions for variable-speed air conditioners, heat pumps, and mini-splits based on NEEP data. Expect results to change, potentially significantly so depending on the scenario.
- Updates deep ground temperatures (used for modeling ground-source heat pumps) using L. Xing's simplified design model (2014).
- Replaces inverse calculations, used to calculate COPs from rated efficiencies, with regressions for single/two-speed central ACs and ASHPs.
- Output updates:
- Breaking change: Disaggregates "EC_x Vent" and "EC_x Dehumid" from "EC_x L&A" in
ERI_Results.csv
. - Adds "Peak Electricity: Annual Total (W)" output.
- Breaking change: Disaggregates "EC_x Vent" and "EC_x Dehumid" from "EC_x L&A" in
- Relaxes requirements for some inputs:
SolarAbsorptance
andEmittance
now only required for exterior walls & rim joists (i.e., ExteriorAdjacentTo=outside).Window/PerformanceClass
no longer required (defaults to "residential").- Allows above-grade basements/crawlspaces defined solely with Wall (not FoundationWall) elements.
- Adds ZERH Multifamily v2.
- Updates to ZERH Single Family v2 windows SHGC in climate zone 4 through 8.
- Allow JSON output files instead of CSV via a new
--output-format JSON
commandline argument.
Bugfixes
- Fixes possible "Electricity category end uses do not sum to total" error for a heat pump w/o backup.
- Fixes error if conditioned basement has
InsulationSpansEntireSlab=true
. - Fixes error if heat pump
CompressorLockoutTemperature
==BackupHeatingLockoutTemperature
. - Fixes ground source heat pump fan/pump adjustment to rated efficiency.
- Fixes missing radiation exchange between window and sky.
- Minor HVAC design load calculation bugfixes for foundation walls.
- Fixes
nEC_x
calculation for a fossil fuel water heater w/ UEF entered. - Various HVAC sizing bugfixes and improvements.
Bugfixes
- Fixes possible "Sum of energy consumptions do not match total" error for shared water heater w/ FractionDHWLoadServed=0.
Bugfixes
- Fixes incorrect ESRD ceiling U-factor for SFA unit with adiabatic ceiling when using SFNH program.
Bugfixes
- Fixes ZERH Single Family v2 mechanical ventilation fan efficiency to use ASRE instead of SRE.
- Fixes error if describing a wall with
WallType/StructuralInsulatedPanel
.
New Features
- Updates to OpenStudio 3.6.1/EnergyPlus 23.1.
- Breaking change: CO2e Index results must now be requested through a new optional
SoftwareInfo/extension/CO2IndexCalculation/Version
input. - Breaking change: Updates to newer proposed HPXML v4.0:
- Replaces
CeilingFan/Quantity
,ClothesWasher/NumberofUnits
, andClothesDryer/NumberofUnits
withCount
. - Replaces
PVSystem/InverterEfficiency
withPVSystem/AttachedToInverter
andInverter/InverterEfficiency
.
- Replaces
- Output updates:
- Breaking change: Adds
End Use: Heating Heat Pump Backup Fans/Pumps
(disaggregated fromEnd Use: Heating Fans/Pumps
). - Breaking change: Replaces
Component Load: Windows
withComponent Load: Windows Conduction
andComponent Load: Windows Solar
. - Breaking change: Replaces
Component Load: Skylights
withComponent Load: Skylights Conduction
andComponent Load: Skylights Solar
. - Breaking change: Adds
Component Load: Lighting
(disaggregated fromComponent Load: Internal Gains
). - Breaking change: Adds "net" values for emissions; "total" values now exclude generation (e.g., PV).
- Adds
Load: Heating: Heat Pump Backup
(heating load delivered by heat pump backup systems). - Adds
System Use
outputs (end use outputs for each heating, cooling, and water heating system); allows requesting timeseries output. - All annual load outputs are now provided as timeseries outputs; previously only "Delivered" loads were available.
- Peak summer/winter electricity outputs are now based on Jun/July/Aug and Dec/Jan/Feb months, not HVAC heating/cooling operation.
- Breaking change: Adds
- Heat pump enhancements:
- Allows
HeatingCapacityRetention[Fraction | Temperature]
optional inputs as a more flexible alternative toHeatingCapacity17F
. - Allows
CompressorLockoutTemperature
andBackupHeatingLockoutTemperature
as optional inputs; alternatives toBackupHeatingSwitchoverTemperature
. - Defaults for
CompressorLockoutTemperature
: 25F for dual-fuel, -20F for mini-split, 0F for all other heat pumps. - Defaults for
BackupHeatingLockoutTemperature
: 50F for dual-fuel, 40F for all other heat pumps. - Increased consistency between variable-speed central HP and mini-split HP models for degradation coefficients, gross SHR calculations, etc.
- Allows
- Duct enhancements:
- Allows modeling ducts buried in attic loose-fill insulation using
Ducts/DuctBuriedInsulationLevel
. - The duct effective R-value can now be found in the ERI___Home.xml files; it accounts for exterior air film, duct shape, and buried insulation level.
- Allows modeling ducts buried in attic loose-fill insulation using
- Allows additional building air leakage inputs (ACH or CFM at user-specified house pressure, Natural CFM, Effective Leakage Area).
- LightingGroup for garage is no longer required if the home doesn't have a garage.
- Weather cache files (*foo-cache.csv) are no longer used/needed.
Bugfixes
- Adds error-checking to ensure that SFA/MF dwelling units have at least one attached wall/ceiling/floor surface.
- Various Manual J HVAC autosizing calculation bugfixes and improvements.
- Ensure that ductless HVAC systems do not have a non-zero airflow defect ratio specified.
New Features
- Adds support for ZERH Single Family v2.
- Updates to ENERGY STAR SFNH Rev 12 and MFNC Rev 03.
WaterHeatingSystem/RecoveryEfficiency
is now an optional input.- Weather cache file (*-cache.csv) is now optional; if not provided, it will be generated on the fly. Provide the cache file for fastest runtime.
- Provide two decimal places in ENERGY STARS/ZERH CSV output files to better prevent user confusion.
- Uses the same
Floor/FloorType
in the Reference Design as the Rated Home for ENERGY STAR MFNC, as per EPA's request. - Changes the windows SHGC in CZ4-8 from 0.40 to 0.30 for ENERGY STAR SFNH National v3.2 and MFNC National v1.2 as per EPA's request.
Bugfixes
- Bugfixes for ENERGY STAR and ZERH programs.
Bugfixes
- Fixes incorrect warning about zip code not found in eGRID/Cambium lookup table.
- Fixes error when a non-electric water heater has jacket insulation and the UEF metric is used.
New Features
- Updates to OpenStudio 3.5.0/EnergyPlus 22.2.
- Breaking change: Updates to newer proposed HPXML v4.0:
- Replaces
FrameFloors/FrameFloor
withFloors/Floor
. Floor/FloorType
(WoodFrame, StructuralInsulatedPanel, SteelFrame, or SolidConcrete) is a required input.- All
Ducts
must now have aSystemIdentifier
. - Replaces
WallType/StructurallyInsulatedPanel
withWallType/StructuralInsulatedPanel
. - Replaces
StandbyLoss
withStandbyLoss[Units="F/hr"]/Value
for an indirect water heater. - Replaces
BranchPipingLoopLength
withBranchPipingLength
for a hot water recirculation system. - Replaces
Floor/extension/OtherSpaceAboveOrBelow
withFloor/FloorOrCeiling
. - For PTAC with heating, replaces
HeatingSystem
of type PackagedTerminalAirConditionerHeating withCoolingSystem/IntegratedHeating*
elements.
- Replaces
- Breaking change: Now performs full HPXML XSD schema validation (previously just limited checks); yields runtime speed improvements.
- Adds ENERGY STAR ERI calculation for SF National v3.2 and MF National v1.2.
- Adds IECC ERI pathway calculation (2015, 2018, 2021).
- Adds Zero Energy Ready Homes calculation for v1.
- Allows SEER2/HSPF2 efficiency types for central air conditioners and heat pumps.
- Allows calculating all programs (e.g., ERI, ENERGY STAR, IECC, etc.) simultaneously while avoiding duplicate EnergyPlus simulations.
- Breaking change: Deprecates energy_star.rb script; energy_rating_index.rb will now run all programs specified in the HPXML.
- Breaking change: The organization of ENERGY STAR output files have changed.
- Allows modeling CFIS ventilation systems with a supplemental fan.
- Breaking change: New
CFISControls/AdditionalRuntimeOperatingMode
input required for CFIS ventilation systems.
- Breaking change: New
- Breaking change: The
ClimateZoneIECC/Year
is now more strict:- All runs must include a 2006 IECC climate zone.
- IECC ERI pathway runs must include an IECC climate zone of the same year.
- ENERGY STAR ERI runs for SF National v3.2 and MF National v1.2 must include a 2021 IECC climate zone.
- Zero Energy Ready Homes v1 runs must include a 2015 IECC climate zone.
- Allows modeling room air conditioners with heating or reverse cycle.
- Allows shared dishwasher/clothes washer to be attached to a hot water distribution system instead of a single water heater.
- Adds HVAC capacities, design loads, and design temperatures to csv output files.
- Annual/timeseries outputs:
- Adds annual emission outputs disaggregated by end use; timeseries emission outputs disaggregated by end use can be requested.
- Allows generating timeseries unmet hours for heating and cooling.
- Adds heating/cooling setpoints to timeseries outputs when requesting zone temperatures.
- Improves Kiva foundation model heat transfer by providing better initial temperature assumptions based on foundation type and insulation levels.
Bugfixes
- Fixes units for Peak Loads (kBtu/hr, not kBtu) in ERI____Home.csv output files.
- Bugfix for increasing HVAC capacities due to installation grading.
- Fixes possible output error for ground source heat pumps with a shared hydronic circulation loop.
- Fixes zero energy use for a ventilation fan w/ non-zero fan power and zero airflow rate.
Bugfixes
- Fixes possible simulation error if a slab has an ExposedPerimeter near zero.
Bugfixes
- Fixes excessive heat transfer when foundation wall interior insulation does not start from the top of the wall.
Bugfixes
- Fixes incorrect ERI calculation when the Rated Home has multiple water heaters.
Bugfixes
- Fixes possible error when running HERS Auto-Generation tests.
New Features
- Updates to OpenStudio 3.4.0/EnergyPlus 22.1.
- Updates to OpenStudio-HPXML 1.4.0.
- Implements ANSI/RESNET/ICC Standard 301-2019 Addenda C & D.
ERICalculation/Version
can now be "2019ABC" or "2019ABCD" in the HPXML files.- Adds calculation of CO2e Rating Index and CO2e/NOx/SO2 emissions (annual and hourly).
- Adds support for shared hot water recirculation systems controlled by temperature.
- Breaking change:
/HPXML/Building/Site
is now required withAddress/StateCode
andAddress/ZipCode
child elements.
- Output changes:
- Adds "Energy Use: Total" and "Energy Use: Net" columns to the ERI____Home.csv output files; allows hourly outputs.
- Breaking change: New "End Use: <Fuel>: Heating Heat Pump Backup" output, disaggregated from "End Use: <Fuel>: Heating".
- Breaking change: Deprecates duct leakage to outside exemptions; software tools must provide duct leakage to outside or DSE.
SoftwareInfo/extension/ERICalculation/Version
enumerations "2014ADEGL", "2014ADEG", "2014ADE" are replaced by "2014AEG" and "2014AE". - Breaking change: For CFIS systems, an
extension/VentilationOnlyModeAirflowFraction
input is now required to address duct losses during ventilation only mode. - Allows
AirInfiltrationMeasurement/InfiltrationHeight
as an optional input; if not provided, it is inferred from other inputs as before. - Allows duct leakage to be entered in units of CFM50 as an alternative to CFM25.
- Adds a
--skip-simulation
flag that can be used to just generate the ERI Rated/Reference Home HPXMLs and then stop. - Adds a
--rated-home-only
flag to run only the ERI Rated Home simulation (ERI will not be calculated). - Simplifies ERI Reference Home configuration with respect to HVAC types and number of DSE distribution systems.
Bugfixes
- Fixes opaque door R-value in the Reference Home in IECC climate zone 1.
- Fixes possible NaN result for ERI if, in a very cold climate, the Reference Home has no cooling load.
New Features
- Updates to OpenStudio 3.3.0/EnergyPlus 9.6.0.
- Breaking change: HVAC grading inputs
FanPowerNotTested
,AirflowNotTested
, andChargeNotTested
are no longer accepted. - Breaking change: Replaces "Unmet Load" outputs with "Unmet Hours".
- Breaking change: Renames "Load: Heating" and "Peak Load: Heating" (and Cooling) outputs to include "Delivered".
- Breaking change: Any heat pump backup heating requires
HeatPump/BackupType="integrated"
to be specified. - Breaking change: HPXML schema version must now be '4.0' (proposed).
- Moves
FoundationWall/Insulation/Layer/extension/DistanceToTopOfInsulation
toFoundationWall/Insulation/Layer/DistanceToTopOfInsulation
. - Moves
FoundationWall/Insulation/Layer/extension/DistanceToBottomOfInsulation
toFoundationWall/Insulation/Layer/DistanceToBottomOfInsulation
. - Moves
Slab/PerimeterInsulationDepth
toSlab/PerimeterInsulation/Layer/InsulationDepth
. - Moves
Slab/UnderSlabInsulationWidth
toSlab/UnderSlabInsulation/Layer/InsulationWidth
. - Moves
Slab/UnderSlabInsulationSpansEntireSlab
toSlab/UnderSlabInsulation/Layer/InsulationSpansEntireSlab
.
- Moves
- Allows modeling PTAC and PTHP HVAC systems.
- Allows additional fuel types for generators.
- Allows non-zero refrigerant charge defect ratios for ground source heat pumps.
- Allows CEER (Combined Energy Efficiency Ratio) efficiency unit for room AC.
- Allows specifying the foundation wall type (e.g., solid concrete, concrete block, wood, etc.).
- Removes error-check for number of bedrooms based on conditioned floor area, per RESNET guidance.
- Introduces a small amount of infiltration for unvented spaces.
ConditionedBuildingVolume
input is no longer needed.- Improves consistency of installation quality calculations for two/variable-speed air source heat pumps and ground source heat pumps.
Bugfixes
- Improves ground reflectance for window interior shading.
- Improves HVAC fan power for central forced air systems.
- Fixes mechanical ventilation compartmentalization area calculation for SFA/MF homes with surfaces with InteriorAdjacentTo==ExteriorAdjacentTo.
- Negative
DistanceToTopOfInsulation
values are now disallowed. - Fixes workflow errors if a
VentilationFan
has zero airflow rate or zero hours of operation. - Fixes heating/cooling seasons (used for e.g. summer vs winter window shading) for the southern hemisphere.
- Relaxes
Overhangs
DistanceToBottomOfWindow vs DistanceToBottomOfWindow validation when Depth is zero. - Fixes possibility of "Construction R-value ... does not match Assembly R-value" error.
New Features
- Revises shared mechanical ventilation preconditioning control logic to operate less often.
New Features
- Adds ENERGY STAR ERI Target workflow for new construction in accordance with ENERGY STAR Certification System for Homes and Apartments Using an Energy Rating Index-Based Compliance Path.
- Optional
SoftwareInfo/extension/EnergyStarCalculation/Version
(values like "SF_National_3.1"; required if running ENERGY STAR calculation). - Breaking change:
Building/Site/Address/StateCode
(values like "CO" or "FL") now required. - Breaking change: For windows,
Window/PerformanceClass
(values of "residential" or "architectural") now required. - Breaking change: For shared boilers,
HeatingSystem/HeatingCapacity
,HeatingSystem/extension/SharedLoopWatts
, andHeatingSystem/extension/FanCoilWatts
(fan coil only) now required. - Breaking change: For air distribution systems with ducts,
AirDistribution/NumberofReturnRegisters
now required. - Breaking change: For shared recirculation hot water systems,
HotWaterDistribution/extension/SharedRecirculation/PumpPower
now required. - Optional
extension/SharedLoopMotorEfficiency
for shared boilers, chillers, cooling towers, and GSHPs w/ shared loop andextension/SharedRecirculation/MotorEfficiency
for shared recirculation hot water systems.
- Optional
- Breaking change: Heating/cooling component loads no longer calculated by default for faster performance; use
--add-component-loads
argument if desired. - Allows
DuctLeakageMeasurement
&ConditionedFloorAreaServed
to not be specified for ductless fan coil systems; Breaking change:AirDistributionType
is now required for all air distribution systems. - Switches room air conditioner model to use Cutler performance curves.
- Shared systems now preserved in the Rated Home (as opposed to configuring, e.g., the equivalent central AC w/ SEEReq for a chiller).
- Removes limitation that a shared water heater serving a shared laundry room can't also serve dwelling unit fixtures (i.e., FractionDHWLoadServed is no longer required to be zero).
- When Reference/Rated water heater fuels are determined by predominant water/space heating fuels, fossil fuel is now selected in the case of a tie.
- Adds IDs to schematron validation errors/warnings when possible.
Bugfixes
- Prevents a solar hot water system w/ SolarFraction=1.
- Fixes room air conditioner performance curve.
- Fixes heating load fractions for boiler w/ WLHP.
- Water loop heat pumps no longer get added electric backup heating in the Rated Home.
New Features
- Revises shared mechanical ventilation preconditioning control logic to operate less often.
New Features
- Allow
Slab/ExposedPerimeter
to be zero. ClothesDryer/ControlType
is no longer required if 301 version >= 2019A- Moves additional error-checking from the ruby measure to the schematron validator.
- Adds more detail to error messages regarding the wrong data type in the HPXML file.
- Adds error-checking for negative SEEReq results for shared cooling systems.
- Relaxes tolerance for duct leakage to outside warning when ducts solely in conditioned space.
Bugfixes
- Fixes ruby error if elements (e.g.,
SystemIdentifier
) exist without the proper 'id'/'idref' attribute. - Fixes error if boiler/GSHP pump power is zero.
- Fixes possible "Electricity category end uses do not sum to total" error due to boiler pump energy.
- Fixes possible "Construction R-value ... does not match Assembly R-value" error for highly insulated enclosure elements.
New Features
- Implements ANSI/RESNET/ICC Standard 301-2019 Addendum B.
ERICalculation/Version
can now be "2019AB" in the HPXML files.- Breaking change: New HVAC installation quality inputs required for air conditioners, heat pumps, and furnaces.
- Adds modeling of dehumidifiers.
- Adds modeling of generators (generic on-site power production).
- Adds modeling of mini-split air conditioners.
- Allows requesting hourly unmet heating/cooling loads.
- Includes hot water loads (in addition to heating/cooling loads) when hourly total loads are requested.
- Breaking change: Simplifies inputs for fan coils and water loop heat pumps by A) removing HydronicAndAirDistribution element and B) moving WLHP inputs from extension elements to HeatPump element.
- Breaking change: One of the three duct leakage input types is now required for AirDistribution systems.
- Breaking change: For ERI____Home.csv output files, the first two sections are now prefixed with "Fuel Use:" and "End Use:", respectively.
- Adds HPXML default values (e.g., Reference Home autosized HVAC capacities) to the four ERI____Home.xml files.
- Overhauls documentation to be more comprehensive and standardized.
Bugfixes
- Improved modeling of window/skylight interior shading -- better reflects shading coefficient inputs.
- Adds various error-checking to the schematron validator.
- Adds error-checking for empty IDs in the HPXML file.
- Fixes possible "Error: Electricity category end uses (X) do not sum to total (X)." for a heat pump water heater.
- Fixes possible OpenStudio ForwardTranslator "surface construction conflicts" errors.
- HVAC sizing improvements for floors above crawlspaces/basements and walls.
- Fixes schematron file not being valid per ISO Schematron standard.
- Fixes error when using energy_rating_index.rb --cache-weather.
New Features
- Updates to OpenStudio 3.1.0/EnergyPlus 9.4.0.
- Breaking change: Deprecates
WeatherStation/WMO
HPXML input, useWeatherStation/extension/EPWFilePath
instead. - Implements water heater Uniform Energy Factor (UEF) model; replaces RESNET UEF->EF regression. Breaking change:
FirstHourRating
is now a required input for storage water heaters when UEF is provided. - Adds optional HPXML fan power inputs for most HVAC system types. Breaking change: Removes ElectricAuxiliaryEnergy input for non-boiler heating systems.
- Uses air-source heat pump cooling performance curves for central air conditioners.
- Accommodates common walls adjacent to unconditioned space by using HPXML surfaces where InteriorAdjacentTo == ExteriorAdjacentTo.
- Additional validation checks and error-checking.
- Various small updates to ASHRAE 140 test files.
- Release packages now include RESNET HERS test files/results; all tests pass RESNET's proposed stringent acceptance criteria.
Bugfixes
- EnergyPlus 9.4.0 fix for negative window solar absorptances at certain hours.
- Fixes ceiling fan configuration in Reference/Rated Homes for 301-2019.
- Fixes airflow timeseries outputs to be averaged instead of summed.
New Features
- New Schematron validation (301validator.xml) replaces custom ruby validation (301validator.rb)
- Ability to model shared systems for Attached/Multifamily dwelling units
- Shared HVAC systems (cooling towers, chillers, central boilers, water loop heat pumps, fan coils, ground source heat pumps on shared hydronic circulation loops)
- Shared water heaters serving either A) multiple dwelling units' service hot water or B) a shared laundry/equipment room, as well as shared hot water recirculation systems
- Shared appliances (e.g., clothes dryer in a shared laundry room)
- Shared ventilation systems (optionally with preconditioning equipment and recirculation)
- Shared PV systems
- [Breaking change]
IsSharedSystem
now required for boilers and ground-to-air heat pumps, water heating systems, ventilation systems, and PV systems - [Breaking change]
IsSharedAppliance
now required for clothes washers, clothes dryers, and dishwashers - [Breaking change] Appliances located in MF spaces (i.e., "other") must now be specified in more detail (i.e., "other heated space", "other non-freezing space", "other multifamily buffer space", or "other housing unit")
- Allows multiple mechanical ventilation systems (
VentilationFan
) - [Breaking change] For hydronic distributions,
HydronicDistributionType
is now required - [Breaking change] For DSE distributions,
AnnualHeatingDistributionSystemEfficiency
andAnnualCoolingDistributionSystemEfficiency
are both always required - [Breaking change] Adds
RadiantBarrierGrade
as a required input if a roof has a radiant barrier - [Breaking change] Adds
extension/PumpPowerWattsPerTon
as a required input for ground-to-air heat pumps - [Breaking change] Renames
DuctLeakageTestingExemption
toDuctLeakageToOutsideTestingExemption
, to clarify that it is different from the total duct leakage testing exemption in ANSI/RESNET/ACCA 310 - [Breaking change] New
FanPowerDefaulted
andFlowRateNotTested
elements must be provided when ventilation systems have defaulted fan power or unmeasured airflow - Allows homes without a refrigerator, dishwasher, range/oven, clothes washer, and/or clothes dryer
- Rated Home equipment capacities now automatically increased if smaller than auto-calculated design loads
- Updates Reference Home to have a single water heater even when there are multiple water heaters
- Updates Reference Home unconditioned basement insulation to be the basement ceiling instead of basement walls
- Updates Reference Home conditioned basement insulation R-values per RESNET SCC clarifications
- Various updates to RESNET test files
- Updates ASHRAE 140 tests to use TMY3 instead of TMY weather
- Adds more reporting of warnings/errors to run.log
Bugfixes
- Fixes pump energy for boilers and ground source heat pumps
- Fixes incorrect gallons of hot water use reported when there are multiple water heaters
- No longer report unmet load for buildings where the HVAC system only meets part of the load (e.g., room AC serving 33% of the load)
- ASHRAE 140 test files now have only heating or cooling systems, not both
New Features
- Implements ANSI/RESNET/ICC Standard 301-2019 and Addendum A. Shared systems are not yet supported.
ERICalculation/Version
can be "2019A" or "2019"- [Breaking change]
Attic/WithinInfiltrationVolume
is required for unvented attics - [Breaking change]
Foundation/WithinInfiltrationVolume
is required for unvented crawlspaces and unconditioned basements ExteriorAdjacentTo
can be "other heated space", "other multifamily buffer space", or "other non-freezing space" forWall
,RimJoist
,FoundationWall
, andFrameFloor
elementsDuctLocation
can be "other housing unit", "other heated space", "other multifamily buffer space", or "other non-freezing space"WaterHeater/Location
can be "other housing unit", "other heated space", "other multifamily buffer space", or "other non-freezing space"- [Breaking change]
Location
is now a required element for dishwashers and cooking ranges. Location
can be "other" for all appliances- [Breaking change]
Window/FractionOperable
is required VentilationFan/TestedFlowRate
is now optional and can be excluded for unmeasured mechanical ventilation flow ratesVentilationFan/FanPower
is now optional and can be excluded for unknown mechanical ventilation fan power- [Breaking change]
LabelUsage
is required for clothes washers - [Breaking change]
LabelElectricRate
,LabelGasRate
,LabelAnnualGasCost
, andLabelUsage
are required for dishwashers - [Breaking change]
HVACDistribution/ConditionedFloorAreaServed
is now required for air distribution systems - [Breaking change] For FrameFloors ExteriorAdjacentTo, "other housing unit above" and "other housing unit below" are replaced with "other housing unit"; floors adjacent to any "other ..." MF space type must have the
extension/OtherSpaceAboveOrBelow
element set to "above" or "below".
- [Breaking change] Lighting inputs now use
LightingType[LightEmittingDiode | CompactFluorescent | FluorescentTube]
instead ofThirdPartyCertification="ERI Tier I" or ThirdPartyCertification="ERI Tier II"
. - Allows "exterior wall", "under slab", and "roof deck" for
DuctLocation
. - Allows
PortableHeater
,Fireplace
, andFloorFurnace
for heating system types. - Allows "wood" and "wood pellets" as fuel types for HVAC systems, water heaters, and appliances.
- Allows additional hourly outputs: airflows (e.g., infiltration, mechanical ventilation, natural ventilation, whole house fan) and weather (e.g., temperatures, wind speed, solar).
- Improved inferred infiltration height calculation for homes w/ conditioned basements.
- Reference Home mechanical ventilation that supplements infiltration is now always a balanced system.
- Additional runtime improvements.
- [Breaking change] Many changes to HPXML test files to conform to latest RESNET Publication 002.
- ERI____Home.xml files:
- [Breaking change]
WaterHeatingSystem/PerformanceAdjustment
is now a multiplier (e.g., 0.92) instead of a derate (e.g., 0.08). - Adds
AirInfiltrationMeasurement/extension/InfiltrationHeight
andAirInfiltrationMeasurement/extension/Aext
as diagnostic outputs.
- [Breaking change]
- Error-checking:
- Adds more space type-specific error checking of adjacent surfaces.
- Adds additional HPXML datatype checks.
- Adds a warning if a
HVACDistribution
system has ducts entirely within conditioned space and non-zero leakage to the outside. - Adds warnings if appliance inputs may be inappropriate and result in negative energy or hot water use.
Bugfixes
- Reference Homes w/ ACs & furnaces now use the same W/cfm (derived from EAE) for both heating and cooling.
- Fixes error if a home has both a dual-fuel heat pump and an air-source heat pump.
- Fixes exterior air film and wind exposure of frame floors over ambient conditions.
- Fixes air films for ceiling surfaces.
- Preserve Rated Home appliance locations in the Reference Home.
- Fixes heat pump defrost control to be Timed instead of OnDemand.
- Fixes error if there's a
FoundationWall
whose height is less than 0.5 ft. - Fixes vented attic ventilation rate.
- Reported unmet heating/cooling load now correctly excludes latent energy.
- Ground-source heat pump backup fuel is now correctly honored instead of always using electricity.
New Features
- [Breaking change] Updates to OpenStudio v3.0.0 and EnergyPlus 9.3.
- [Breaking change] Allows 301-2014 Addenda D & L to be used by providing inputs for A) duct leakage testing exemptions or B) total duct leakage in lieu of leakage to the outside. These inputs should only be used if the conditions specified in ANSI/RESNET/ICC© 301 have been appropriately met. Enumerations for
SoftwareInfo/extension/ERICalculation/Version
are now "latest", "2014ADEGL", "2014ADEG", "2014ADE", "2014AD", "2014A", "2014". - [Breaking change]
BuildingConstruction/ResidentialFacilityType
is now required. Valid choices are: "single-family detached", "single-family attached", "apartment unit", "manufactured home". - Improves inferred infiltration height for conditioned basements (including walkout basements).
- A new HPXML input
WeatherStation/extension/EPWFilePath
can be used instead ofWeatherStation/WMO
to point directly to the EPW file of interest. - Adds hot water outputs (gallons), disaggregated by end use, to annual output. Also available for timeseries outputs.
- Improved desuperheater model; can now be connected to heat pump water heaters.
- Solar thermal systems modeled with
SolarFraction
can now be connected to combi water heating systems. - Small improvement to calculation of component loads.
- Allows buildings to have HVAC systems that do not condition 100% of the load (i.e., where sum of fraction heat/cool load served is greater than zero and less than one).
- Populates more information in the ERI___Home.xml files (e.g., plug load kWh/yr).
- [Breaking change] The
--no-ssl
argument has been deprecated. - [Breaking change] Switches from
BuildingConstruction/extension/FractionofOperableWindowArea
toWindow/FractionOperable
in HPXML test files.
Bugfixes
- Fixes an unsuccessful simulation for buildings with multiple HVAC air distribution systems, each with multiple duct locations.
- Fixes an unsuccessful simulation for buildings where the sum of multiple HVAC systems' fraction load served was slightly above 1 due to rounding.
- Small fix for interior partition wall thermal mass model.
Breaking changes
- The
--skip-validation
or-s
argument has been removed, it's no longer needed now that the primary runtime bottleneck has been addressed. - ERI____Home.csv output files:
- Disaggregates "Electricity: Heating Fans/Pumps" from "Electricity: Heating", "Electricity: Cooling Fans/Pumps" from "Electricity: Cooling", and "Electricity: Television" from "Electricity: Plug Loads"
- Renames "Annual Load" to "Load" and "Annual Unmet Load" to "Unmet Load"
- Requesting hourly output is now done via an
--hourly TYPE
(e.g.,--hourly fuels --hourly temperatures
) argument instead of--hourly-output
. See documentation for more details. - Weather cache files are now in .csv instead of .cache format. Re-run
--cache-weather
if using custom weather files. extension/StandbyLoss
changed toStandbyLoss
for indirect water heaters.Site/extension/DisableNaturalVentilation
changed toBuildingConstruction/extension/FractionofOperableWindowArea
for ASHRAE 140-based test files.
New Features
- Allows modeling of whole-house fans.
- Adds optional
CompressorType
input for ACs/ASHPs. - Improved natural ventilation algorithm that reduces the potential for incurring additional heating energy.
- Improved calculation of component heating/cooling loads.
- Hot water temperatures are now included in the ERI____Home.xml files.
- Runtime performance improvements, particularly for Windows.
- Additional hourly outputs can be requested: energy by end use, total heating/cooling loads, and component heating/cooling loads.
- ERI version in the HPXML file can now be entered as "latest".
- Additional HPXML error-checking.
Bugfixes
- Fix for central fan integrated supply (CFIS) fan energy.
- Fix simulation error when
FractionHeatLoadServed
(orFractionCoolLoadServed
) sums to slightly greater than 1. - Fix for running simulations on a different drive (either local or remote network).
- Fix for HVAC sizing error when latitude is exactly 64 (Big Delta, Alaska).
- Fix for DSE not being incorporated in the heating/cooling in ERI____Home_Hourly.csv output files.
- Fix potential simulation error for buildings with foundation walls.
- Fix radiation heat transfer when conditioned basement walls have a window/door.
- Fixes weather download location.
- Fixes Rated Home infiltration rate for homes with below-grade stories and using natural ACH.
Breaking changes
- OpenStudio version 2.9.1 is now required.
- The
--hourly-output
argument now only generates hourly output for the Reference/Rated Homes, not the IAD Homes, for faster runtime. - Foundation walls described with the
Insulation/Layer
approach now require two layers (i.e., interior and exterior). (Foundation walls described using theInsulation/AssemblyEffectiveRValue
approach are unchanged.) See here for more information.
New Features
- Runtime performance improvements for all buildings.
- Adds dual fuel heat pump model with a switchover temperature input.
- Adds solar hot water models. Inputs are either a system-level solar fraction or detailed collector inputs for flat-plate, evacuated tube, and ICS systems.
- Allows input for indirect water heater (combi boiler) standby losses.
- Allows separate interior vs exterior foundation wall insulation elements.
- Allows foundation wall insulation that doesn't start at the top of the wall.
Bugfixes
- Fixes Reference Home HVAC sizing when the house has a conditioned basement.
- Fixes basement slab insulation being ignored.
- Fixes possible issue with ground-source heat pump ground loop sizing.
- Fixes return duct losses and duct component load reporting.
- Fixes desuperheater model bugs.
- Fixes/updates to Proposed HERS Method Test HPXML files
- Errors are now generated for duplicate
SystemIdentifier
IDs, as they are supposed to be unique per the HPXML schema and can result in unpredictable behavior.
Known Issues
- None
Breaking changes
- A
Foundations/Foundation[FoundationType/Basement[Conditioned='false']]/ThermalBoundary
element is now required for all buildings with unconditioned basements. - Several reporting changes for results/ERI____Home.csv output files:
- "Other Fuel" is now disaggregated into "Fuel Oil" and "Propane"
- Peak load units are changed from W to kBtu
New Features
- Adds ability to specify evaporative coolers
- Adds heating/cooling component loads reporting to results/ERI____Home.csv output files. See the Outputs documentation for more information.
- When an
AirDistribution
is specified, only supply duct leakage is now required. Return duct leakage, supply ducts, and return ducts are now optional.
Bugfixes
- Improves combi boiler model to achieve better control/accuracy.
- Changes the recovery efficiency (RE) of the Reference Home water heater for consistency with other software tools.
- Changes the thermal boundary location for unconditioned basements in the Reference Home configuration for consistency with other software tools.
- Fixes bug where presence of a radiant barrier was not being reflected in the model.
- Fixes Reference Home configuration for thermal boundary vs. exterior thermal boundary surfaces.
- Fixes bug where a couple FoundationWall elements were not being properly validated.
- Improves handling of uninsulated foundation walls defined by assembly R-value.
Known Issues
- Desuperheater savings is not correct. The issue is being investigated.
- Return duct losses may not be correct. Heating/cooling loads do not include return duct loads. These issues are being investigated.
Breaking changes
- None
New Features
- Adds thermostat information (setpoints, setbacks/setups, ceiling fan offset) to all the configured homes' HPXMLs.
- Runtime improvements for homes with heat pump water heaters.
- Runtime improvements for homes with slabs/crawlspaces/basements.
- Reduces number of simulations for Reference/IAD Auto-Generation tests.
- Simulations are now immediately aborted when an error occurs.
Bugfixes
- Fixes significant runtime regression for more complex homes.
- Fixes possibility of IAD Home skylight area exceeding roof area.
- Fixes Reference Home R-values for non-thermal boundary surfaces.
- Fixes entered setpoints being used in the Rated Home.
- Fixes infiltration credit erroneously being applied to SFA/MF mechanical ventilation rates.
- Fixes cooling system's Sensible Heat Ratio not being preserved in the Reference Home.
- Fixes attic/crawlspace ventilation rates appearing in the Reference Home HPXML even when there's no vented attic/crawlspace.
- Fixes zero mechanical ventilation energy when CFIS systems are set to run exactly 24 hrs/day.
- Fixes ceiling fans running year-round instead of only during certain months.
- Fixes Reference Home mechanical ventilation when infiltration is entered as CFM50.
- Increases precision of some outputs (that were previously rounded to 0.01 GJ).
Known Issues
- Energy results for combination boilers may be incorrect by a few percentage points. The issue is still being investigated.
Breaking changes
- Requires OpenStudio 2.9.0
- The root
HPXML
element needs to be changed from http://hpxmlonline.com/2014/6 to http://hpxmlonline.com/2019/10 per the latest HPXML v3 schema. Slab/DepthBelowGrade
is now required whenSlab/InteriorAdjacentTo=’garage’
.FrameFloor/ExteriorAdjacentTo
must now be either 'other housing unit above' or 'other housing unit below' instead of 'other housing unit'.HeatPump/HeatingCapacity
is now a required element.- Several reporting changes for results/ERI____Home.csv output files:
- Hot water recirculation pump energy is now disaggregated.
- Lighting energy is disaggregated into interior vs exterior vs garage.
- Hot water load related to tank losses are now reported.
- Summer/winter peak electricity consumption values are now reported.
- Peak heating/cooling loads are now reported.
- A couple reporting changes for HERS test results:
- Hot water tests: Hot water recirculation pump energy is now disaggregated.
- ASHRAE 140 tests: Load results are separated into heating/cooling categories.
New Features
- Adds an optional
--hourly-output
argument to request an hourly output CSV file that includes zone temperatures and energy uses disaggregated by fuel. - Adds ability to model a desuperheater attached to a ground source heat pump, air source heat pump, or air conditioner.
- Adds
SensibleHeatFraction
as a new optional input for air conditioners. - Adds
CoolingSensibleHeatFraction
andHeatingCapacity17F
as new optional inputs for heat pumps. - Improves modeling of ERVs/HRVs (compared to mechanical ventilation systems without energy recovery).
- Improves modeling of conditioned basements (radiation heat exchange and solar distribution).
- Improves modeling of exterior incident solar for walls/roofs/etc. without an
Azimuth
provided. - Allows tests to be run in parallel without clobbering each other on the filesystem.
Bugfixes
- Prevent E+ simulation error due to near zero autosized heating/cooling airflow rate.
- Fixes incorrect reference in EPvalidator.rb for
FoundationWall
. - Fixes possible "Cannot create a surface with vertices" error.
- Fixes possible "Unable to calculate a construction for using the provided assembly R-value" errors.
- Fixes possible "Electric category end uses do not sum to total" error for heat pumps.
- Fixes possible "Sum of conditioned floor surface areas is greater than ConditionedFloorArea specified" error for buildings with adiabatic ceilings.
- Fixes possible "Two airloops found for CFIS" error.
- Fixes error when a
FoundationWall
is completely below-grade (i.e.,DepthBelowGrade
=Height
). - Fixes the infiltration rate in the conditioned basement ASHRAE 140 tests (L322XC and L324XC) and other HERS tests derived thereof.
- Fixes HERS hot water tests not passing when pasted into the RESNET spreadsheet.
- Fixes modeling of leakage to outside when all ducts are in conditioned space.
- Fixes modeling tankless water heaters when the home has >5 or <1 bedrooms.
- Fixes error for HVAC systems with zero heating/cooling capacity.
- Fixes error for duct locations that have only supply (or only return) ducts.
- Various minor fixes to HERS test files.
- Adds better error-checking if surfaces are missing -- for example, a garage ceiling/roof.
- Adds error-checking for stranded
HVACDistribution
elements (i.e., not referenced by an HVAC system). - Adds error-checking for a negative water heater standby loss coefficient (UA).
Known Issues
- Energy results for combination boilers may be incorrect by a few percentage points. The issue is still being investigated.
Breaking changes
VentilationFan/RatedFlowRate
is nowTestedFlowRate
.- Several reporting changes for results/ERI____Home.csv output files:
- Disaggregated natural gas from other fuels.
- Changed PV energy generation to a negative number.
- Added heating, cooling, and hot water loads.
- Added unmet heating and cooling loads.
New Features
- General runtime performance improvements.
- Combination boilers, which provide both space and water heating, can be specified. Use
WaterHeatingSystem/WaterHeaterType
and pointWaterHeatingSystem/RelatedHVACSystem
to aHeatingSystem
of type boiler. - Water heater tank wrap insulation can be optionally specified via
WaterHeatingSystem/WaterHeaterInsulation/Jacket/JacketRValue
. - Improved foundation modeling for more complex configurations (e.g., walkout basements, multiple foundation walls/slabs with different insulation properties, etc.)
WaterHeatingSystem/HeatingCapacity
is now optional.Slab/DepthBelowGrade
is now only required for slab foundation types.- Custom weather files can now be used.
Bugfixes
- Improved approach for distribution system efficiency (DSE).
- Improved approach for calculation of Reference End Use Loads (REUL).
- Improved approach for calculation of water heater energy consumption adjustment due to delivery effectiveness.
- Fixed workflow errors if paths had spaces in them.
- Various fixes to test/sample HPXML files.
- Fixed fan power of (non-CFIS) mechanical ventilation systems when hours of operation is less than 24.
- Fixed possible error when trying to use custom weather files.
Known Issues
- Combination boiler results are currently incorrect; this will be resolved in a future release that uses EnergyPlus v9.2.
- Heating/cooling energy use for homes with conditioned basements will likely change a bit in a future version.
- Heating/cooling loads are incorrectly reported for Rated Homes that have ERVs or HRVs; the ERI calculation is not affected.
Breaking changes
CoolingSystemType="central air conditioning"
is now"central air conditioner"
(consistent with"room air conditioner"
)
New Features
- Now passes Reference Home Auto-Generation tests (specifically e-Ratio test)
- Allows HRVs/ERVs to be specified with
AdjustedSensibleRecoveryEfficiency
andAdjustedTotalRecoveryEfficiency
(instead ofSensibleRecoveryEfficiency
andTotalRecoveryEfficiency
) - Allows ducts to be located outside (
DuctLocation="outside"
) - Allows water heaters to be located outside (
Location="other exterior"
) - All simulation/HPXML/etc. files generated from running tests are now saved to the
workflow/tests/test_files
directory
Bugfixes
- Fixes ERI Reference Home mechanical ventilation when Rated Home has no mechanical ventilation
- Fixes ERI Rated Home mechanical ventilation and infiltration when Rated Home has no mechanical ventilation
- Fixes missing heating system in HVAC2b.xml test file
- Fixes heat pump sizing when
FractionHeatLoadServed
andFractionCoolLoadServed
are different (e.g., ERI Reference Homes when Rated Home heating system is electric) - Heat pumps now sized based on the max of heating and cooling loads
- Initial beta release