Version 12.0.0

Version 12.0.0 is a major release that adds various new packages and models.

The library has been tested with Dymola 2025x, OpenModelica 1.24.0, OPTIMICA 1.55.11 and recent versions of Impact.

The following major changes have been done compared to release 11.1.0:

• The EnergyPlus coupling has been update to EnergyPlus 24.2.0, and the implementation that uses EnergyPlus 9.6.0 has been moved to the Obsolete package.
• The package Buildings.Fluid.Geothermal.ZonedBorefields has been added that allows modeling geothermal borefields in which groups of boreholes are operated with different mass flow rates
  and inlet temperatures, for example to create a hot core and warm perimeter.
• The template models for air-source heat pump and chiller plants has been updated to allow an optional side-stream water-to-water heat recovery heat pump, and to allow optional buffer tanks
  on the hot or cold side. Also, its control has been updated.
• The control sequences in the package Buildings.DHC.ETS and Buildings.DHC.Plants have been updated to comply with ASHRAE Standard 231P (Control Description Language).
• For pumps, fans, valves and dampers, changed the model for the actuator position. The new implementation changes the actuator position at a constant speed defined by the rise time (fans and pumps) or
  the stroke time (valves and dampers) rather than a second order filter. This gives more realistic response, and also simplifies the control loop tuning.

Also, many models have been updated to improve performance, to improve compliance with the Modelica Language Standard and to correct model errors.

Full Changelog: v11.0.0...v12.0.0

Version 11.1.0

Version 11.1.0 is backward compatible with 11.0.0.

The library has been tested with Dymola 2024x Refresh 1, OpenModelica 1.24.0, OPTIMICA 1.55.11 and recent versions of Impact.

This backward compatible version adds a new package with heat pump models that can be operate in reversible mode to provide heating or cooling, and that can be configured to use various approaches to compute performance, such as data tables or Carnot analogy.

Also, many models have been updated to improve performance, to ensure compliance with the Modelica Language Standard and to correct model errors.

Full Changelog: v11.0.0...v11.1.0

Version 10.1.1

Version 10.1.1 is backward compatible with 10.0.0 and 10.1.0.

The library has been tested with Dymola 2024x Refresh 1, OpenModelica 1.24.0, OPTIMICA 1.55.11 and recent versions of Impact.

Models have been updated to improve performance, to ensure compliance with the Modelica Language Standard and to correct model errors.

Full Changelog: v10.1.0...v10.1.1

Version 11.0.0

Version 11.0.0 is a major release that adds various new packages and models.

The library has been tested with Dymola 2024x, OpenModelica 1.22.1-1, OPTIMICA 1.48.2 and recent versions of Impact.

The following major changes have been done compared to release 10.1.0:

• A package for central plants with reversible air-to-water heat pumps has been added to Buildings.Templates.Plants.HeatPumps. The package allows configuration of the type of hydronic integration.
• The models for 1st to 5th generation district heating and cooling systems have been expanded and revised, a user guide has been added, and the models have been moved from the package Buildings.Experimental.DHC to Buildings.DHC.
• A package for domestic hot water generation and loads that are served by a district system has been added to Buildings.DHC.Loads.HotWater.
• The initialization of the Spawn model has been refactored to avoid an iteration between Modelica and EnergyPlus as this caused numerical problems for some model configurations.
• The implementation of the blocks for the Control Description Language (CDL), which is being standardized through ASHRAE Standard 231P, has been revised to comply with the latest draft of the standard.
• A tutorial for how to build a simple system model has been added to Buildings.Examples.Tutorial.SimpleHouse.

Full Changelog: v10.1.0...v11.0.0

Version 10.1.0

Version 10.1.0 is backward compatible with version 10.0.0.

The library has been tested with Dymola 2024x, OpenModelica 1.22.1-1, OPTIMICA 1.43.4 and recent versions of Impact.

The following major changes have been done compared to release 10.0.0:

• A package to model aquifer thermal energy storage has been added.

Many models have been updated to improve performance, for compliance with the Modelica Language Standard and to correct model errors.

Full Changelog: v10.0.0...v10.1.0

Version 9.1.2

Version 9.1.2 is backward compatible with 9.1.0 and 9.1.1, except that relative to 9.1.0, the Spawn binaries need to be updated as described in Buildings.ThermalZones.EnergyPlus_9_6_0.UsersGuide.Installation.

The library has been tested with Dymola 2023x, OpenModelica 1.22.0-dev (41-g8a5b18f-1), OPTIMICA 1.43.4 and recent versions of Impact.

This backward compatible version adds a heat meter sensor and it adds a new example that demonstrates how to use a hydronic radiator with the updated Spawn interface. Also, many models have been updated to improve performance, for compliance with the Modelica Language Standard and to correct model errors.

Version 10.0.0

Version 10.0.0 is a major release that adds various new packages and models.

The library has been tested Dymola 2023x, OpenModelica 1.22.0-dev (41-g8a5b18f-1), OPTIMICA 1.43.4 and recent versions of Impact.

The following major changes have been done compared to release 9.1.1:

• A package with configurable template models for variable air volume flow systems with control based on ASHRAE Guideline 36 has been added to Buildings.Templates.
• Reduced order building envelope models based on the ISO 13790:2008 Standard have been added. This allows modeling of building envelope heat transfer either with a detailed Modelica multizone model (Buildings.ThermalZones.Detailed), with EnergyPlus via the Spawn coupling (Buildings.ThermalZones.EnergyPlus_9_6_0), or with reduced order models based on ISO 13790 (Buildings.ThermalZones.ISO13790) or based on VDI 6007 (Buildings.ThermalZones.ReducedOrder).
• Various models for district energy systems have been added to the package Buildings.Experimental. This package includes models for
  • combined heating and cooling district energy systems that operate near ambient temperature (sometimes called 5th generation district energy systems),
  • Energy Transfer Stations (ETS) with all electric plants with heat recovery chillers,
  • ETS with multiple heat pumps (heat recovery as well as air-source heat pumps) and storage, i.e., the so-called Time-Independent Energy Recovery (TIER) plant in (Buildings.Experimental.DHC.Plants.Combined.AllElectricCWStorage),
  • direct and indirect ETS for heating or for cooling, and
  • district steam systems.
• A package with all major hydronic configurations that are encountered in heating and cooling systems has been added in Buildings.Fluid.HydronicConfigurations. This package also includes automatic sizing of control valves to obtain suitable valve authority.
• The fan and pump models have been revised, and can now be configured to compute the part load efficiency based on the Euler number.
• Various new elementary control blocks have been added to the Buildings.Controls.OBC.CDL package to provide a reference implementation of the ASHRAE Standard 231P Control Description Language that is currently being developed. See also obc.lbl.gov.

Version 9.1.1

Version 9.1.1 is backward compatible with 9.1.0, except that the Spawn binaries need to be updated as described in Buildings.ThermalZones.EnergyPlus_9_6_0.UsersGuide.Installation.

The library has been tested with Dymola 2023x, OpenModelica 1.22.0-dev (41-g8a5b18f-1), OPTIMICA 1.43.4 and recent versions of Impact.

The Spawn binaries have been updated from version 0.3.0 to 0.4.3. Both use the same EnergyPlus input data files from EnergyPlus 9.6.0. The update corrects a bug that caused EnergyPlus to always send a heat capacitance multiplier of 1 to Modelica (see #3481).

Version 9.1.0

Version 9.1.0 is backward compatible with 9.0.0.

The library has been tested with Dymola 2023x, OpenModelica 1.20.0-dev (314-g3033f43-1), OPTIMICA (revision 2022-05-09-master-4b0cd2bf71) and recent versions of Impact.

The following major changes have been done:

• The ASHRAE Guideline 36 air-side sequences have been updated to the official release. They are in the package Buildings.Controls.OBC.ASHRAE.G36. The previous public release draft is still distributed with this version.
• Various new blocks for the Control Description Language have been added to the package Buildings.Controls.OBC.CDL.
• The flow rate control in various examples has been improved to avoid large pump or fan heads if the mass flow rate is prescribed rather than computed based on the pump or fan curve.
• Various models have been improved for robustness, for compatibility with the Modelica.Media library, and to correct errors.

Version 9.0.0

Version 9.0.0 is a major release that updates the Modelica version from 3.2.3 to 4.0.0.

The library has been tested with Dymola 2022x, OpenModelica 1.19.0-dev (613-gd6e04c0-1), OPTIMICA (revision 2022-05-09-master-4b0cd2bf71) and recent versions of Impact.

The following major changes have been done:

• The Modelica version has been updated from version 3.2.3 to 4.0.0.
• Most fluid component models have been updated to remove the parameter massDynamics, which is now set to the same value as the parameter energyDynamics.
• The models for coupling with EnergyPlus have been moved to the package Buildings.ThermalZones.EnergyPlus_9_6_0 to allow support for more than one EnergyPlus version in future releases.
• The BESTEST validation in the package Buildings.ThermalZones.Detailed.Validation.BESTEST has been updated to the latest BESTEST version, and new tests have been added.
• The package Buildings.Fluid.Geothermal.BuriedPipes has been added to model heat transfer between buried pipes and the ground, such as for district energy systems.
• The package Buildings.Media.Steam for modeling steam has been added.
• Various new models have been added to the package Buildings.Airflow.Multizone for modeling multizone air exchange.
• Models for ice tanks have been added to the package Buildings.Fluid.Storage.Ice.
• Various models, such as for PV, solar collectors and thermal zones have been improved to obtain the latitude of the building from the weather data bus, rather than requiring the user to specify it.
• The run-time coupling with Python has been updated to Python version 3.8, and it has been renamed to Buildings.Utilities.IO.Python_3_8.
• Various other models have been improved or added, in particular for modeling of control sequences using the Control Description Language that has been developed in the OpenBuildingControl project at https://obc.lbl.gov.