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I have currently modeled a VRF system for LEED v3-2009 for a facility in CO, USA under Xcel SG & CG-S tariff structures. While the energy savings are great (~45%), the energy cost savings are not so great (~4%). My baseline currently adheres to System 5 (VAV with DX & HW Fossil Fuel Boiler). I have heard from other's in the industry that for Ground Source Heat Pumps jobs they have noticed energy models using electricity as the source energy for heating in their baseline model to avoid "fuel-switching".

As such, I would like to pose the question as to what the fuel source should be in the baseline energy model for heating if you are modeling VRF (electricity or natural gas)? I am unable to find any mention of this fuel-switching issue in ASHRAE 90.1 -2007 and would like to be certain before making a change. In addition, feedback on the energy/cost savings results you have seen when modeling VRF systems would be interesting to hear.

Brian

I have currently modeled a VRF system for LEED v3-2009 for a facility in CO, USA under Xcel SG & CG-S tariff structures. While the energy savings are great (~45%), the energy cost savings are not so great (~4%). My baseline currently adheres to System 5 (VAV with DX & HW Fossil Fuel Boiler). I have heard from other's in the industry that for Ground Source Heat Pumps jobs they have noticed energy models using electricity as the source energy for heating in their baseline model to avoid "fuel-switching".

As such, I would like to pose the question as to what the fuel source should be in the baseline energy model for heating if you are modeling VRF (electricity or natural gas)? I am unable to find any mention of this fuel-switching issue in ASHRAE 90.1 -2007 and would like to be certain before making a change. In addition, feedback on the

If you have modeled a VRF system, it would be interesting to hear energy/cost savings results you have seen when modeling VRF systems would be interesting to hear.to provide us all with a "ballpark" of current models being made.

Brian

I have currently modeled a VRF system for LEED v3-2009 for a facility in CO, USA under Xcel SG & CG-S tariff structures. While the energy savings are great (~45%), the energy cost savings are not so great (~4%). My baseline currently adheres to System 5 (VAV with DX & HW Fossil Fuel Boiler). I have heard from other's in the industry that for Ground Source Heat Pumps jobs they have noticed energy models using electricity as the source energy for heating in their baseline model to avoid "fuel-switching".

As such, I would like to pose the question as to what the fuel source should be in the baseline energy model for heating if you are modeling VRF (electricity or natural gas)? I am unable to find any mention of this fuel-switching issue in ASHRAE 90.1 -2007 and would like to be certain before making a change.

If you have modeled a VRF system, it would also be interesting to hear energy/cost savings results you have seen to provide us all with a "ballpark" of current models being made.

Brian

I have currently modeled a VRF system for LEED v3-2009 for a facility in CO, USA under the following tariff structures: Xcel SG & CG-S tariff structures. CG-S. While the energy savings are great (~45%), the energy cost savings are not so great (~4%). My baseline currently adheres to System 5 (VAV with DX & HW Fossil Fuel Boiler). I have heard from other's in the industry that for Ground Source Heat Pumps jobs they have noticed energy models using electricity as the source energy for heating in their baseline model to avoid "fuel-switching".

As such, I would like to pose the question as to what the fuel source should be in the baseline energy model for heating if you are modeling VRF (electricity or natural gas)? I am unable to find any mention of this fuel-switching issue in ASHRAE 90.1 -2007 and would like to be certain before making a change.

If you have modeled a VRF system, it would also be interesting to hear energy/cost savings results you have seen to provide us all with a "ballpark" of current models being made.

Brian

I have currently modeled a VRF system for LEED v3-2009 for a facility in CO, USA under the following tariff structures: Xcel SG & CG-S. While the energy savings are great (~45%), the energy cost savings are not so great (~4%). My baseline currently adheres to System 5 (VAV with DX & HW Fossil Fuel Boiler). I have heard from other's in the industry that for Ground Source Heat Pumps jobs they have noticed seen energy models using electricity as the source energy for heating in their baseline model to avoid "fuel-switching". "fuel-switching" when going to VRF.

As such, I would like to pose the question as to what the fuel source should be in the baseline energy model for heating if you are modeling VRF (electricity or natural gas)? I am unable to find any mention of this fuel-switching issue in ASHRAE 90.1 -2007 and would like to be certain before making a change.

If you have modeled a VRF system, it would also be interesting to hear energy/cost savings results you have seen to provide us all with a "ballpark" of current models being made.

Brian

I have currently modeled a VRF system for LEED v3-2009 for a facility in CO, USA under the following tariff structures: Xcel SG & CG-S. While the energy savings are great (~45%), the energy cost savings are not so great (~4%). My baseline currently adheres to System 5 (VAV with DX & HW Fossil Fuel Boiler). I have heard from other's in the industry that for Ground Source Heat Pumps jobs they have seen energy models using electricity as the source energy for heating in their baseline model to avoid "fuel-switching" when going to VRF. in the proposed model.

As such, I would like to pose the question as to what the fuel source should be in the baseline energy model for heating if you are modeling VRF (electricity or natural gas)? I am unable to find any mention of this fuel-switching issue in ASHRAE 90.1 -2007 and would like to be certain before making a change.

If you have modeled a VRF system, it would also be interesting to hear energy/cost savings results you have seen to provide us all with a "ballpark" of current models being made.

Brian

I have currently modeled a VRF system for LEED v3-2009 for a facility in CO, USA under the following tariff structures: Xcel SG & CG-S. While the energy savings are great (~45%), the energy cost savings are not so great (~4%). My baseline currently adheres to System 5 (VAV with DX & HW Fossil Fuel Boiler). I have heard from other's in the industry that for Ground Source Heat Pumps jobs they have seen energy models using electricity as the source energy for heating in their baseline model to avoid "fuel-switching" in the proposed model.

As such, I would like to pose the question as to what the What fuel source should be in the baseline energy model for heating if you are modeling VRF VRF/Ground Source (electricity or natural gas)? I am unable to find any mention of this fuel-switching issue how to address "fuel-switching" in ASHRAE 90.1 -2007 and would like to be certain before making a change.

If Also, if you have modeled a VRF system, it would also be interesting feel free to hear provide your energy/cost savings results you have seen to provide us all with a "ballpark" of current models being made.results!

Brian

I have currently modeled a VRF system for LEED v3-2009 for a facility in CO, USA under the following tariff structures: Xcel SG & CG-S. While the energy savings are great (~45%), the energy cost savings are not so great (~4%). My baseline currently adheres to System 5 (VAV with DX & HW Fossil Fuel Boiler). I have heard from other's in the industry that for Ground Source Heat Pumps jobs they have seen energy models using electricity as the source energy for heating in their baseline model to avoid "fuel-switching" in the proposed model.

What fuel source should be in the baseline energy model for heating if you are modeling VRF/Ground Source (electricity or natural gas)? I am unable to find any mention of how to address "fuel-switching" in ASHRAE 90.1 -2007 and would like to be certain before making a change.

Also, if you have modeled a VRF system, feel free to provide your energy/cost savings results!

Brian

I have currently modeled a VRF system for LEED v3-2009 for a facility in CO, USA under the following tariff structures: Xcel SG & CG-S. While the energy savings are great (~45%), the energy cost savings are not so great (~4%). My baseline currently adheres to System 5 (VAV with DX & HW Fossil Fuel Boiler). I have heard from other's in the industry that for Ground Source Heat Pumps jobs they have seen energy models using electricity as the source energy for heating in their baseline model to avoid "fuel-switching" in the proposed model.

What fuel source should be in the baseline energy model for heating if you are modeling VRF/Ground Source (electricity or natural gas)? I am unable to find any mention of how to address "fuel-switching" in ASHRAE 90.1 -2007 and would like to be certain before making a change.

Also, if you have modeled a VRF system, feel free to provide your energy/cost savings results!

Brian