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@kyle benne is working on this in the tertiary loops branch of OpenStudio.

We've used a simplification for a very complex and innovative central plant that includes reversing chillers by changing the EnergyPlus IDD to allow electric boiler efficiencies above unity along with an EP measure to set the boiler efficiency to account for overall system COP/EER.

In our case, the central plant was modeled by the MEP designer in Transys with total cooling efficiency of ~38 COP and heating efficiency of ~5.5 COP.

@kyle benne is working on this in the tertiary loops branch of OpenStudio.

We've used a simplification for a very complex and innovative central plant that includes reversing chillers by changing the EnergyPlus IDD file included with the OS install* to allow electric boiler efficiencies above unity along with an EP measure to set the boiler efficiency to account for overall system COP/EER.

In our case, the central plant was modeled by the MEP designer in Transys with total cooling efficiency of ~38 COP and heating efficiency of ~5.5 COP.

@kyle benne is working on this in the tertiary loops branch of OpenStudio.

We've used a simplification for a very complex and innovative central plant that includes reversing chillers by changing the EnergyPlus IDD file included with the OS install* install (C:\Program Files\OpenStudio 1.10.3\share\openstudio\EnergyPlusV8-4-0\Energy+.idd) to allow electric boiler efficiencies above unity along with an EP measure to set the boiler efficiency to account for overall system COP/EER.

In our case, the central plant was modeled by the MEP designer in Transys with total cooling efficiency of ~38 COP and heating efficiency of ~5.5 COP.

@kyle benne is working on this in the tertiary loops branch of OpenStudio.

We've used a simplification for a very complex and innovative central plant that includes reversing chillers by changing the EnergyPlus IDD file included with the OS install (C:\Program Files\OpenStudio 1.10.3\share\openstudio\EnergyPlusV8-4-0\Energy+.idd) (1) to allow electric boiler efficiencies above unity along with an EP measure to set the boiler efficiency to account for overall system COP/EER.

In our case, the central plant was modeled by the MEP designer in Transys with total cooling efficiency of ~38 COP and heating efficiency of ~5.5 COP.

@kyle benne is working on this in the tertiary loops branch of OpenStudio.

We've used a simplification for a very complex and innovative central plant that includes reversing chillers by changing the EnergyPlus IDD file included with the OS install (1) (*) to allow electric boiler efficiencies above unity along with an EP measure to set the boiler efficiency to account for overall system COP/EER.

In our case, the central plant was modeled by the MEP designer in Transys with total cooling efficiency of ~38 COP and heating efficiency of ~5.5 COP.

(1) (*) C:\Program Files\OpenStudio 1.10.3\share\openstudio\EnergyPlusV8-4-0\Energy+.idd)

@kyle benne is working on this in the tertiary loops branch of OpenStudio.

We've used Since the CentralHeatPumpSystem object is not available in the OS API yet we've been using a simplification for a very complex and innovative central plant that includes reversing chillers by changing chillers, thermal energy storage, and a water main HX.

In our case, the EnergyPlus IDD MEP designer modeled the central plant in Transys and determined that the total system efficiency was COP-3.7 for heating and COP-37.7 for cooling. Our simplification involves altering the Energy+.idd file included installed with the OS install (*) to allow electric boiler efficiencies above a thermal efficiency greater than unity along with an EP measure to set the boiler efficiency to account for overall system COP/EER. efficiency.

@kyle benne is working on this in the tertiary loops branch of OpenStudio.

Since the CentralHeatPumpSystem object is not available in the OS API yet we've been using a simplification for a very complex and innovative central plant that includes reversing chillers, thermal energy storage, and a water main HX.

In our case, the MEP designer modeled the central plant in Transys TNRSYS and determined that the total system efficiency was COP-3.7 for heating and COP-37.7 for cooling. Our simplification involves altering the Energy+.idd file installed with OS to allow a thermal efficiency greater than unity along with an EP measure to set the boiler efficiency.

@kyle benne is working on this enabling the CentralHeatPumpSystem in the tertiary loops branch of OpenStudio.

Since the CentralHeatPumpSystemOpenStudio repository. The object is object is not available in the OS API yet we've been using API, but doesn't work yet, i.e.

chps = OpenStudio::Model::CentralHeatPumpSystem.new(model)

uninitialized constant OpenStudio::Model::CentralHeatPumpSystem (NameError)

For a simplification for a very complex and innovative central plant that includes project of ours involving reversing chillers, thermal energy storage, a geo field, and a water main HX.

In our case, HX, the MEP designer designers modeled the central plant in TNRSYS TRNSYS and determined that the total system efficiency was COP-3.7 for annual heating and COP-37.7 cooling efficiencies.

As a simplification we used an electric BoilerHotWater and ChillerElectricEIR for cooling. Our simplification involves altering the Energy+.idd central plant and used the COPs from the TRNSYS model for the Nominal Thermal Efficiency and Reference COP fields.

This approach required changing the Energy+.idd file installed with OS to allow a thermal efficiency boiler efficiencies greater than unity along with an EP measure to set the boiler efficiency. this value.

@kyle benne is working on enabling the CentralHeatPumpSystem in the tertiary loops branch of the OpenStudio repository. The object is available in the OS API, but doesn't work yet, i.e.

chps = OpenStudio::Model::CentralHeatPumpSystem.new(model)

uninitialized constant OpenStudio::Model::CentralHeatPumpSystem (NameError)

For a project of ours involving reversing chillers, thermal energy storage, and HX with a geo field, ground source and water main HX, source, the MEP designers modeled the central plant in TRNSYS and determined the annual heating and cooling efficiencies.

As a simplification we used an electric BoilerHotWater and ChillerElectricEIR for the central plant and used the COPs from the TRNSYS model for the Nominal Thermal Efficiency and Reference COP fields.

This approach required changing the Energy+.idd file installed with OS to allow boiler efficiencies greater than unity along with an EP measure to set this value.