Confusing HB energy consumption with DOAS

grasshopper honeybee
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Hello everyone, I have a question on the energy consumption breakdowns that we get in Honeybee using different HVAC templates.

I am simulating a large complex building and want to get an estimate of the energy consumption. My preferred method to do this is to calculate the heating/cooling load from the model, and multiply this with an estimated sCOP. The ventilation energy is found by extrating the ventilation rate from the simulation and multiplying it with a fixed SFP.

To simulate the heating/cooling loads, I use the Ideal Air Loads template. Settings: 60% HR efficiency and Tsupply= 30 / 17oC. I then get the following results using the HB to OSM simulation, with the following End Use Intensity:

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What I would like to know is whether the calculated heating and cooling loads also contain the energy needed to heat/cool the supply air to 30/17oC, or if it is only the heating/cooling in the room itself. Becaust if it the indicated heating/cooling load is for both the ventilation air and the space, I should be able to take the heating/cooling output and divide it by the sCOP of my heat pump to get a proper estimate of the energy consumption right?

Then another question: when I switch the HVAC to another template (DOAS with WSHP and GSHP), my EUI changes drastically. However, where can I see an explanation of what the end uses mean?

  • Does the heating/cooling output include a particular sCOP, or still none? If it is without, i could multiply the value with the sCOP to get a consumption estimate.
  • What does the output ‘doas fans’ mean? Is this thermal, or electrical energy?

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Basically, I want to get a good estimate of the total Ecooling/Eheating of the building. I can then manually convert it to consumption from there, by using sCOP and known figures for auxilary energy of pumps, fans, DHW, lighting, etc. What would be the best way to get to that?

Thank you in advance! :slight_smile:

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I have found a description of the ‘ideal HVAC’ in EnergyPlus, but am not getting any wiser either sadly…

This object provides an ideal system to supply conditioned air to the zone that meets all the load requirements and consumes no energy. It is often used for load calculations, an evaluation where the load components of the building are all that is being investigated, or as the first step to a more realistic model of a building.

This component can be operated with infinite or finite heating and cooling capacity. For either mode – infinite or limited capacity – the user can also specify on/off schedules for heating and cooling and outdoor air controls. There are also optional controls for dehumidification, humidification, economizer, and heat recovery. This component may be used in combination with other HVAC equipment serving the same zone.

This component can be thought of as an ideal unit that mixes air at the zone exhaust condition with the specified amount of outdoor air and then adds or removes heat and moisture at 100% efficiency in order to produce a supply air stream at the specified conditions. The energy required to condition the supply air is metered and reported as [DistrictHeating] and [DistrictCooling.]

So does the output ‘heating’ and ‘cooling’ in Honeybee include this District Heating and Cooling load of bringing the air brought into the room as well?