OpenStudio-ERI v0.9.0 Beta

OpenStudio-ERI 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-ERI workflow calculates an Energy Rating Index (ERI) using the Department of Energy's OpenStudio/EnergyPlus building simulation platform. The open-source workflow is intended to be used by residential software tools that provide a HPXML building description file.

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

Please visit the OpenStudio-ERI v0.9.0 Beta documentation for instructions on how to get started, how to connect software tools to the workflow, etc.

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 of WeatherStation/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 to Window/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.

OpenStudio-ERI v0.8.0 Beta

OpenStudio-ERI 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-ERI workflow calculates an Energy Rating Index (ERI) using the Department of Energy's OpenStudio/EnergyPlus building simulation platform. The open-source workflow is intended to be used by residential software tools that provide a HPXML building description file.

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

Please visit the OpenStudio-ERI v0.8.0 Beta documentation for instructions on how to get started, how to connect software tools to the workflow, etc.

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 to StandbyLoss for indirect water heaters.
• Site/extension/DisableNaturalVentilation changed to BuildingConstruction/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 (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).
• 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.

OpenStudio-ERI v0.7.0 Beta

OpenStudio-ERI version 0.7.0 Beta has been released.

The OpenStudio-ERI workflow calculates an Energy Rating Index (ERI) using the Department of Energy's OpenStudio/EnergyPlus building simulation platform. The open-source workflow is intended to be used by residential software tools that provide a HPXML building description file.

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

Please visit the OpenStudio-ERI v0.7.0 Beta documentation for instructions on how to get started, how to connect software tools to the workflow, etc.

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 the Insulation/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

OpenStudio-ERI v0.6.0 Beta

OpenStudio-ERI version 0.6.0 Beta has been released.

The OpenStudio-ERI workflow calculates an Energy Rating Index (ERI) using the Department of Energy's OpenStudio/EnergyPlus building simulation platform. The open-source workflow is intended to be used by residential software tools that provide a HPXML building description file.

OpenStudio-ERI v0.6.0 Beta uses OpenStudio v2.9.0, EnergyPlus v9.2.0, and a proposed HPXML v3.0.

Please visit the OpenStudio-ERI v0.6.0 Beta documentation for instructions on how to get started, how to connect software tools to the workflow, etc.

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.

OpenStudio-ERI v0.5.0 Beta

OpenStudio-ERI version 0.5.0 Beta has been released.

The OpenStudio-ERI workflow calculates an Energy Rating Index (ERI) using the Department of Energy's OpenStudio/EnergyPlus building simulation platform. The open-source workflow is intended to be used by residential software tools that provide a HPXML building description file.

OpenStudio-ERI v0.5.0 Beta uses OpenStudio v2.9.0, EnergyPlus v9.2.0, and a proposed HPXML v3.0.

Please visit the OpenStudio-ERI v0.5.0 Beta documentation for instructions on how to get started, how to connect software tools to the workflow, etc.

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.

OpenStudio-ERI v0.4.0 Beta

OpenStudio-ERI version 0.4.0 Beta has been released.

The OpenStudio-ERI workflow calculates an Energy Rating Index (ERI) using the Department of Energy's OpenStudio/EnergyPlus building simulation platform. The open-source workflow is intended to be used by residential software tools that provide a HPXML building description file.

OpenStudio-ERI v0.4.0 Beta uses OpenStudio v2.9.0, EnergyPlus v9.2.0, and a proposed HPXML v3.0.

Please visit the OpenStudio-ERI v0.4.0 Beta documentation for instructions on how to get started, how to connect software tools to the workflow, etc.

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 when Slab/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 and HeatingCapacity17F 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.

OpenStudio-ERI v0.3.0 Beta

OpenStudio-ERI version 0.3.0 Beta has been released.

The OpenStudio-ERI workflow calculates an Energy Rating Index (ERI) using the Department of Energy's OpenStudio/EnergyPlus building simulation platform. The open-source workflow is intended to be used by residential software tools that provide a HPXML building description file.

OpenStudio-ERI v0.3.0 Beta uses OpenStudio v2.8.1, EnergyPlus v9.1.0, and a proposed HPXML v3.0.

Please visit the OpenStudio-ERI v0.3.0 Beta documentation for instructions on how to get started, how to connect software tools to the workflow, etc.

Breaking Changes

• VentilationFan/RatedFlowRate is now TestedFlowRate.
• 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 point WaterHeatingSystem/RelatedHVACSystem to a HeatingSystem 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.

OpenStudio-ERI v0.2.0 Beta

OpenStudio-ERI version 0.2.0 Beta has been released.

The OpenStudio-ERI workflow calculates an Energy Rating Index (ERI) using the Department of Energy's OpenStudio/EnergyPlus building simulation platform. The open-source workflow is intended to be used by residential software tools that provide a HPXML building description file.

OpenStudio-ERI v0.2.0 Beta uses OpenStudio v2.8.1, EnergyPlus v9.1.0, and a proposed HPXML v3.0.

Please visit the OpenStudio-ERI v0.2.0 Beta documentation for instructions on how to get started, how to connect software tools to the workflow, etc.

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 and AdjustedTotalRecoveryEfficiency (instead of SensibleRecoveryEfficiency and TotalRecoveryEfficiency)
• 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 and FractionCoolLoadServed 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

OpenStudio-ERI v0.1.0 Beta

OpenStudio-ERI version 0.1.0 Beta has been released.

The OpenStudio-ERI workflow calculates an Energy Rating Index (ERI) using the Department of Energy's OpenStudio/EnergyPlus building simulation platform. The open-source workflow is intended to be used by residential software tools that provide a HPXML building description file.

OpenStudio-ERI v0.1.0 Beta uses OpenStudio v2.8.1, EnergyPlus v9.1.0, and a proposed HPXML v3.0.

Please visit the OpenStudio-ERI v0.1.0 Beta documentation for instructions on how to get started, how to connect software tools to the workflow, etc.

• Initial beta release