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Cooling useful energy

asked 2021-05-22 03:52:42 -0500

J Monteiro's avatar

updated 2021-05-25 14:12:14 -0500

What's the best way to get the anual cooling energy of a building? In the results report I get the final energy, but I need the useful energy, that is, before the program uses the efficiency of the air conditioning equipment.

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maybe if you Set the eficiency of equipments Equals 1

Fernando_Ferreira's avatar Fernando_Ferreira  ( 2021-05-22 14:02:46 -0500 )edit

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answered 2021-05-25 08:00:52 -0500

Keigo's avatar

I'm not sure exactly what your definition of 'the useful energy' is, but the sum of Cooling Coil Total Cooling Rate does not consider the effect of Pump Shaft Power, which heats chilled water and becomes a load on chillers. The cooling load from Pump Shaft Power is normally 3 to 5% of total cooling load. I think we should not ignore it.

When I want to know the the total cooling load of a whole building, I select Chiller Evaporator Cooling Rate in Output Variables and sum up the cooling rate of all chillers. Below is my understanding of the relationship between each Output Variable.

Σ(Chiller Evaporator Cooling Rate)

= Σ(Cooling Coil Total Cooling Rate) + Σ(Pump Shaft Power)

= Plant Supply Side Cooling Demand Rate + Plant Supply Side Unmet Demand Rate

When I use not chillers but VRFs, I select VRF Heat Pump Total Cooling Rate and sum up the cooling rate of all VRFs.

Please refer to here or other description of Output Variables.

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Ok thanks Keigo

J Monteiro's avatar J Monteiro  ( 2021-05-26 12:42:14 -0500 )edit

answered 2021-05-24 09:27:02 -0500

Depending on the type of cooling equipment you are using, you might be looking for Output:Meter,CoolingCoils:EnergyTransfer or Output:Meter,Cooling:EnergyTransfer, both of which are reported in Joules. Check out the I/O reference page on Output:Meter. If you want to combine meters, check out Meter:Custom page.

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Thamks codybond. Do you know how can I activate those meters is Openstudio?

J Monteiro's avatar J Monteiro  ( 2021-05-24 09:46:32 -0500 )edit

I don't, but maybe this post will help.

codybond's avatar codybond  ( 2021-05-24 10:01:32 -0500 )edit

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Asked: 2021-05-22 03:52:42 -0500

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Last updated: May 26 '21