Power Consumption of Chiller


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Old 04-15-09, 08:03 AM
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Power Consumption of Chiller

Dear all,

I am a student. I am dealing with a academic research about power consumption estimation of a industrial used chiller, specially for HVAC of a building. I have done some mathematics model to estimate the power consumption based on some know factors (ex: chiller supply,return temperature, condenser flow rate etc). I am wondering what i can do after i can predict the power consumption in a particular situation. How to optimize the power usage of the chiller. Can you guys give me some advice. Thank You.
 
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Old 04-16-09, 06:26 PM
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optimize the power usage of the chiller?

While this is a Homeowner geared site, I'll attempt to give you an answer because I understand what you are asking.

Depending on the size of the chiller you will have many steps of loading and unloading. Power consumption will be dependent on the % of load on the chiller.

Amps times Volts = Watts.

If your set point is 45 degrees and the water temp is 60 the chiller should be fully loaded. Max watts or power consumption. But as the water temp drops the chiller will unload in steps and therefore reduce power consumption.

The manufacturer should have this data available, watts per stage of load. Or you could rune the chiller manual in different stages and take your own readings.

I would plan for the max consumption and use the less load consumption as a "gimme".

Don't forget setback control, which should be in the electronics, a chiller is normally designed for a 10 degree delta T. If sized correctly the chiller will have no problem handling the load.
 
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Old 04-17-09, 07:10 AM
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Originally Posted by Jarredsdad
While this is a Homeowner geared site, I'll attempt to give you an answer because I understand what you are asking.

Depending on the size of the chiller you will have many steps of loading and unloading. Power consumption will be dependent on the % of load on the chiller.

Amps times Volts = Watts.

If your set point is 45 degrees and the water temp is 60 the chiller should be fully loaded. Max watts or power consumption. But as the water temp drops the chiller will unload in steps and therefore reduce power consumption.

The manufacturer should have this data available, watts per stage of load. Or you could rune the chiller manual in different stages and take your own readings.

I would plan for the max consumption and use the less load consumption as a "gimme".

Don't forget setback control, which should be in the electronics, a chiller is normally designed for a 10 degree delta T. If sized correctly the chiller will have no problem handling the load.
Thank you for replying

Of course the power consumption will be lower as the temp is lower. But for a HVAC system of a building. What can i do or how to reduce the power consumption?
 
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Old 04-17-09, 04:01 PM
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Well now I need more info.

What is the Make, Model and Serial of the chiller?

What does the chiller serve? Do you have VAV boxes? Or Fan Coil units?

What controls the building? Johnson controls, Trane Varitrac or Tracer?
 
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Old 04-17-09, 05:36 PM
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Originally Posted by adrian116
Dear all,

I am a student. I am dealing with a academic research about power consumption estimation of a industrial used chiller, specially for HVAC of a building. I have done some mathematics model to estimate the power consumption based on some know factors (ex: chiller supply,return temperature, condenser flow rate etc). I am wondering what i can do after i can predict the power consumption in a particular situation. How to optimize the power usage of the chiller. Can you guys give me some advice. Thank You.
A classic ASHRAE magazine question! Are you familiar with that engineering magazine?
 
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Old 04-17-09, 06:20 PM
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Excellent

EC, glad you stopped by! Had thought of sending an invite to join the discussion.

Now that I reread the original post. Adrian, are you talking about an existing building or a hypothetical in the class room?

Basically, we know that the chiller will use less power when the load is low. But the load is the building.

So in the real world the chiller is going to make what ever temp water you want.

But if the building is not properly controlled you maybe putting a load on the chiller when it is not necessary.

In the real world there can be several different scenarios you could use here which would effect the chillers operation and of course power consumption.

So, the question is this a real world situation or are you doing this in class as an exercise?
 

Last edited by Jarredsdad; 04-17-09 at 06:45 PM.
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Old 04-18-09, 01:58 PM
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Originally Posted by Jarredsdad
EC, glad you stopped by! Had thought of sending an invite to join the discussion.
Well -you know me -I'm roaming all over this board.

That magazine(I have some at home) has had articles where submissions are made by Ph.D's, corporations and universities soliciting others to help solve vexxing HVAC issues. Some are fun to simply read the title description of. They rank up there with rocket science.

Adrian's question would be one for that magazine - and probably already researched and papers done on it! if not, plenty of people to contact could be found in that magazine.
 
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Old 04-18-09, 11:05 PM
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Originally Posted by Jarredsdad
Well now I need more info.

What is the Make, Model and Serial of the chiller?

What does the chiller serve? Do you have VAV boxes? Or Fan Coil units?

What controls the building? Johnson controls, Trane Varitrac or Tracer?
Thank for replying.

I am noting doing a power optimization of a built building. So i don't have the information. I am doing a research that what i can do to improve the power consumption of a chiller if i know what the power will be at a particular condition. Actually i am doing it somehow related to Johnson controls.
 
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Old 04-18-09, 11:10 PM
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Originally Posted by ecman51`
A classic ASHRAE magazine question! Are you familiar with that engineering magazine?
NO. I didn't. Of course i want it if you would like to give me some related information in the web.
 
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Old 04-18-09, 11:15 PM
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Originally Posted by Jarredsdad
EC, glad you stopped by! Had thought of sending an invite to join the discussion.

Now that I reread the original post. Adrian, are you talking about an existing building or a hypothetical in the class room?

Basically, we know that the chiller will use less power when the load is low. But the load is the building.

So in the real world the chiller is going to make what ever temp water you want.

But if the building is not properly controlled you maybe putting a load on the chiller when it is not necessary.

In the real world there can be several different scenarios you could use here which would effect the chillers operation and of course power consumption.

So, the question is this a real world situation or are you doing this in class as an exercise?
Thanks for replying

Actually, i am doing a final year project and real world situation may be suitable.
 
 

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