Chiller Efficiency

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Hi Bldg-Sim Community,
I had a confusion that you all might be help out.
When someone says that they want a chiller with 25% more efficiency than the
baseline dictated by ASHRAE 90.1, does it mean the COP should be 25%
greater?
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Thanks

Sincerely,
Amit Bhansali, M.S. , EIT

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Maybe you can tell me what the COP of a chiller means then, given that it
varies with load, how do you come up with a single COP for a chiller? Or is
it just the average COP given the operating conditions that the chiller
experiences? Or are you talking about the integrated part load value?

But yes, however you define the efficiency, (COP, EER, or Power/Ton), I am
geussing that the load removed per unit of input will have to increase by
25%.

Matthew Kimball

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Well, the baseline COP are measured at standard testing conditions. So i am
not debating the fact the COP would be constant. I just needed to know that
what does increase in 25% efficiency actuallu mean. I personally thought
having a chiller whose kw/ton was lower than that recommended by ASHRAE
90.1 would be good. Needed to confirm that.

Thanks for the input

--
Thanks

Sincerely,
Amit Bhansali, M.S. , EIT

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Finding, say, a 500-ton centrifugal chiller with a rated COP of 7.625
(6.1 required by ASHRAE * 1.25) is not going to be an easy task.

I think you should look at finding a chiller whose annual energy
consumption is 25% less than an ASHRAE 90.1 chiller (ie 25%
"better")...that's a much more reasonable expectation, given
frictionless bearings, VFDs, etc.

James Hansen, PE, LEED AP

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