OpenStudio-HPXML v1.0.0

OpenStudio-HPXML version 1.0.0 has been released. Two packages are available, a minimal zip with a handful of weather files and full zip with all US TMY3 weather files.

The OpenStudio-HPXML workflow uses HPXML building description files to run residential simulations on the Department of Energy's OpenStudio/EnergyPlus building simulation platform.

OpenStudio-HPXML v1.0.0 uses OpenStudio v3.1.0, EnergyPlus v9.4.0, and a proposed HPXML v3.1.

Please visit the OpenStudio-HPXML v1.0.0 documentation for instructions on how to get started, how to generate an appropriate HPXML file, etc.

New Features

• Updates to OpenStudio 3.1.0/EnergyPlus 9.4.0.
• Breaking change: Deprecates WeatherStation/WMO HPXML input, use WeatherStation/extension/EPWFilePath instead; also removes weather_dir argument from HPXMLtoOpenStudio measure.
• 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.
• Updates rated fan power assumption for mini-split heat pump models.
• Allows coal fuel type for non-boiler heating systems.
• Accommodates common walls adjacent to unconditioned space by using HPXML surfaces where InteriorAdjacentTo == ExteriorAdjacentTo.
• Adds optional HPXML inputs to define whether a clothes dryer is vented and its ventilation rate.
• Adds optional HPXML input for SimulationControl/CalendarYear for TMY weather files.
• Schematron validation improvements.
• Adds some HPXML XSD schema validation and additional error-checking.
• Various small updates to ASHRAE 140 test files.
• Reduces number of EnergyPlus output files produced by using new OutputControlFiles object.
• Release packages now include ASHRAE 140 test files/results.

Bugfixes

• EnergyPlus 9.4.0 fix for negative window solar absorptances at certain hours.
• Fixes airflow timeseries outputs to be averaged instead of summed.
• Updates HVAC sizing methodology for slab-on-grade foundation types.
• Fixes an error that could prevent schematron validation errors from being produced.
• Skips weather caching if filesystem is read only.

OpenStudio-HPXML v0.11.0 Beta

OpenStudio-HPXML version 0.11.0 Beta has been released. Two packages are available, a minimal zip with a handful of weather files and full zip with all US TMY3 weather files.

The OpenStudio-HPXML workflow uses HPXML building description files to run residential simulations on the Department of Energy's OpenStudio/EnergyPlus building simulation platform.

OpenStudio-HPXML v0.11.0 Beta uses OpenStudio v3.0.0, EnergyPlus v9.3.0, and a proposed HPXML v3.1.

Please visit the OpenStudio-HPXML v0.11.0 Beta documentation for instructions on how to get started, how to generate an appropriate HPXML file, etc.

New Features

• New Schematron validation (EPvalidator.xml) replaces custom ruby validation (EPvalidator.rb)
• [Breaking Change] BuildingConstruction/ResidentialFacilityType ("single-family detached", "single-family attached", "apartment unit", or "manufactured home") is a required input
• 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 hot water recirculation systems
  • Shared appliances (e.g., clothes dryer in a shared laundry room)
  • Shared hot water recirculation systems
  • Shared ventilation systems (optionally with preconditioning equipment and recirculation)
  • Shared PV systems
  • [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")
• Enclosure
  • New optional inputs: Roof/RoofType, Wall/Siding, and RimJoist/Siding
  • New optional inputs: Skylight/InteriorShading/SummerShadingCoefficient and Skylight/InteriorShading/SummerShadingCoefficient
  • New optional inputs: Roof/RoofColor, Wall/Color, and RimJoist/Color can be provided instead of SolarAbsorptance
  • New optional input to specify presence of flue/chimney, which results in increased infiltration
  • Allows adobe wall type
  • Allows AirInfiltrationMeasurement/HousePressure to be any value (previously required to be 50 Pa)
  • [Breaking Change] Roof/RadiantBarrierGrade input now required when there is a radiant barrier
• HVAC
  • Adds optional high-level HVAC autosizing controls
    • AllowIncreasedFixedCapacities: Describes how HVAC equipment with fixed capacities are handled. If true, the maximum of the user-specified fixed capacity and the heating/cooling design load will be used to reduce potential for unmet loads. Defaults to false.
    • UseMaxLoadForHeatPumps: Describes how autosized heat pumps are handled. If true, heat pumps are sized based on the maximum of heating and cooling design loads. If false, heat pumps are sized per ACCA Manual J/S based on cooling design loads with some oversizing allowances for heating design loads. Defaults to true.
  • Additional HVAC types: mini-split air conditioners and fixed (non-portable) space heaters
  • Adds optional inputs for ground-to-air heat pumps: extension/PumpPowerWattsPerTon and extension/FanPowerWattsPerCFM
• Ventilation
  • Allows multiple whole-home ventilation, spot ventilation, and/or whole house fans
• Appliances & Plug Loads
  • Allows multiple Refrigerator and Freezer
  • Allows Pool, HotTub, PlugLoad of type "electric vehicle charging" and "well pump", and FuelLoad of type "grill", "lighting", and "fireplace"
  • [Breaking Change] "other" and "TV other" plug loads now required
• Lighting
  • Allows lighting schedules and holiday lighting
• [Breaking Change] For hydronic distributions, HydronicDistributionType is now required
• [Breaking Change] For DSE distributions, AnnualHeatingDistributionSystemEfficiency and AnnualCoolingDistributionSystemEfficiency are both always required
• Allows more HPXML fuel types to be used for HVAC, water heating, appliances, etc.
• New inputs to define Daylight Saving period; defaults to enabled
• 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)
• Schedule bugfix for leap years

OpenStudio-HPXML v0.10.0 Beta

OpenStudio-HPXML version 0.10.0 Beta has been released. Two packages are available, a minimal zip with a handful of weather files and full zip with all US TMY3 weather files.

The OpenStudio-HPXML workflow uses HPXML building description files to run residential simulations on the Department of Energy's OpenStudio/EnergyPlus building simulation platform.

OpenStudio-HPXML v0.10.0 Beta uses OpenStudio v3.0.0, EnergyPlus v9.3.0, and a proposed HPXML v3.1.

Please visit the OpenStudio-HPXML v0.10.0 Beta documentation for instructions on how to get started, how to generate an appropriate HPXML file, etc.

New Features

• Dwelling units of single-family attached/multifamily buildings:
  • Adds new generic space types "other heated space", "other multifamily buffer space", and "other non-freezing space" for surface ExteriorAdjacentTo elements. "other housing unit", i.e. adiabatic surfaces, was already supported.
  • [Breaking Change] For FrameFloors, replaces "other housing unit above" and "other housing unit below" enumerations with "other housing unit". All four "other ..." spaces must have an extension/OtherSpaceAboveOrBelow property set to either "above" or "below".
  • Allows ducts and water heaters to be located in all "other ..." spaces.
  • Allows all appliances to be located in "other", in which internal gains are neglected.
• Allows Fireplace and FloorFurnace for heating system types.
• Allows "exterior wall", "under slab", and "roof deck" for DuctLocation.
• Allows "wood" and "wood pellets" as fuel types for additional HVAC systems, water heaters, and appliances.
• Allows Location to be provided for Dishwasher and CookingRange.
• Allows BuildingSummary/Site/SiteType ("urban", "suburban", or "rural") to be provided.
• Allows user-specified Refrigerator and CookingRange schedules to be provided.
• HVAC capacity elements are no longer required; if not provided, ACCA Manual J autosizing calculations will be used (-1 can continue to be used for capacity elements but is discouraged).
• Duct locations/areas can be defaulted by specifying supply/return Duct elements without DuctSurfaceArea and DuctLocation. HVACDistribution/DistributionSystemType/AirDistribution/NumberofReturnRegisters can be optionally provided to inform the default duct area calculations.
• [Breaking Change] Lighting inputs now use LightingType[LightEmittingDiode | CompactFluorescent | FluorescentTube] instead of ThirdPartyCertification="ERI Tier I" or ThirdPartyCertification="ERI Tier II".
• [Breaking Change] HVACDistribution/ConditionedFloorAreaServed is now required for air distribution systems.
• [Breaking Change] Infiltration and attic ventilation specified using natural air changes per hour now uses ACHnatural instead of extension/ConstantACHnatural.
• [Breaking Change] The optional PerformanceAdjustment input for instantaneous water heaters is now treated as a performance multiplier (e.g., 0.92) instead of derate (e.g., 0.08).
• Adds ASHRAE 140 Class II test files.
• SimulationOutputReport reporting measure:
  • New optional timeseries outputs: airflows (e.g., infiltration, mechanical ventilation, natural ventilation, whole house fan) and weather (e.g., temperatures, wind speed, solar).
  • Timeseries frequency can now be set to 'none' as an alternative to setting all include_timeseries_foo variables to false.
  • [Breaking Change] Renames "Wood" to "Wood Cord" to better distinguish from "Wood Pellets".
• Modeling improvements:
  • Improved calculation for infiltration height
  • Infiltration & mechanical ventilation now combined using ASHRAE 62.2 Normative Appendix C.
• Runtime improvements:
  • Optimized ruby require calls.
  • Skip ViewFactor calculations when not needed (i.e., no conditioned basement).
• 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

• Fixes error if there's a FoundationWall whose height is less than 0.5 ft.
• Fixes HVAC defrost control in EnergyPlus model to use "Timed" instead of "OnDemand".
• Fixes exterior air film and wind exposure for a FrameFloor over ambient conditions.
• Fixes air films for a FrameFloor ceiling.
• Fixes error if there are additional LightingGroup elements beyond the ones required.
• 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.

OpenStudio-HPXML v0.9.0 Beta

OpenStudio-HPXML version 0.9.0 Beta has been released. Two packages are available, a minimal zip with a handful of weather files and full zip with all US TMY3 weather files.

The OpenStudio-HPXML measure translates a HPXML building description file into a residential building model for the Department of Energy's OpenStudio/EnergyPlus building simulation platform.

OpenStudio-HPXML v0.9.0 Beta uses OpenStudio v3.0.0, EnergyPlus v9.3.0, and a proposed HPXML v3.1.

Please visit the OpenStudio-HPXML v0.9.0 Beta documentation for instructions on how to get started, how to generate an appropriate HPXML file, etc.

New Features

• [Breaking Change] Updates to OpenStudio v3.0.0 and EnergyPlus 9.3
• Numerous HPXML inputs are now optional with built-in defaulting, particularly for water heating, appliances, and PV. Set the debug argument to true to output a in.xml HPXML file with defaults applied for inspection. See the documentation for defaulting equations/assumptions/references.
• [Breaking Change] If clothes washer efficiency inputs are provided, LabelUsage is now required.
• [Breaking Change] If dishwasher efficiency inputs are provided, LabelElectricRate, LabelGasRate, LabelAnnualGasCost, and LabelUsage are now required.
• Adds optional specification of simulation controls including timestep and begin/end dates.
• Adds optional extension/UsageMultiplier inputs for appliances, plug loads, lighting, and water fixtures. Can be used to, e.g., reflect high/low usage occupants.
• Adds ability to model a dehumidifier.
• Adds ability to model kitchen/bath fans (spot ventilation).
• Improved desuperheater model; desuperheater can now be connected to heat pump water heaters.
• Updated clothes washer/dryer and dishwasher models per ANSI/RESNET/ICC 301-2019 Addendum A.
• Solar thermal systems modeled with SolarFraction can now be connected to combi water heating systems.
• [Breaking Change] Replaces optional epw_output_path and osm_output_path arguments with a single optional output_dir argument; adds an optional debug argument.
• [Breaking Change] Replaces optional BuildingConstruction/extension/FractionofOperableWindowArea with optional Window/FractionOperable.
• [Breaking Change] Replaces optional extension/EPWFileName with optional extension/EPWFilePath to allow absolute paths to be provided as an alternative to just the file name.
• Replaces REXML xml library with Oga for better runtime performance.
• Additional error-checking.
• SimulationOutputReport reporting measure:
  • Now reports wood and wood pellets
  • Can report monthly timeseries values if requested
  • Adds hot water outputs (gallons) for clothes washer, dishwasher, fixtures, and distribution waste.
  • Small improvement to calculation of component loads

Bugfixes

• Fixes possible simulation error for buildings with complex HVAC/duct systems.
• Fixes handling of infiltration induced by duct leakage imbalance (i.e., supply leakage != return leakage). Only affects ducts located in a vented crawlspace or vented attic.
• 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.
• Skip building surfaces with areas that are extremely small.

OpenStudio-HPXML v0.8.0 Beta

OpenStudio-HPXML version 0.8.0 Beta has been released. Two packages are available, a minimal zip with a handful of weather files and full zip with all US TMY3 weather files.

The OpenStudio-HPXML measure translates a HPXML building description file into a residential building model for the Department of Energy's OpenStudio/EnergyPlus building simulation platform.

OpenStudio-HPXML v0.8.0 Beta uses OpenStudio v2.9.1, EnergyPlus v9.2.0, and a proposed HPXML v3.1.

Please visit the OpenStudio-HPXML v0.8.0 Beta documentation for instructions on how to get started, how to generate an appropriate HPXML file, etc.

Breaking Changes

• Weather cache files are now in .csv instead of .cache format.
• extension/StandbyLoss changed to StandbyLoss for indirect water heaters.
• Site/extension/DisableNaturalVentilation changed to BuildingConstruction/extension/FractionofOperableWindowArea for more granularity.

New Features

• Adds a SimulationOutputReport reporting measure that provides a variety of annual/timeseries outputs in CSV format.
• Allows modeling of whole-house fans to address cooling.
• Improved natural ventilation algorithm that reduces the potential for incurring additional heating energy.
• Optional HotWaterTemperature input for water heaters.
• Optional CompressorType input for air conditioners and air-source heat pumps.
• Allows specifying the EnergyPlus simulation timestep.
• Runtime performance improvements.
• Additional HPXML error-checking.

Bugfixes

• Fix for central fan integrated supply (CFIS) fan energy.
• Fix simulation error when FractionHeatLoadServed (or FractionCoolLoadServed) 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).
• Fixes running simulations when there is no weather cache file.
• Fixes view factors when conditioned basement foundation walls have a window/door.
• Fixes weather file download.
• Allow a building with ceiling fans and without lighting.

OpenStudio-HPXML v0.7.0 Beta

OpenStudio-HPXML version 0.7.0 Beta has been released.

The OpenStudio-HPXML measure translates a HPXML building description file into a residential building model for the Department of Energy's OpenStudio/EnergyPlus building simulation platform.

OpenStudio-HPXML v0.7.0 Beta uses OpenStudio v2.9.1, EnergyPlus v9.2.0, and a proposed HPXML v3.0.

Please visit the OpenStudio-HPXML v0.7.0 Beta documentation for instructions on how to get started, how to generate an appropriate HPXML file, etc.

• Initial beta release