Two Questions for the esteemed members of this fine list

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I am working on modeling a small computer room. The computers are the
major load. The space is served by a small water cooled chiller and an
air handler, with economizer. The questions are:

1) Does EnergyPlus lend itself to such models, and are there specific
tools that might be useful? I am interested in accurately modeling the
computer with varying loads over the year, and with the economizer
enabled to show the difference in various supply air temperatures and
cooling tower strategies (multiple versus one cooling tower, variable
versus multiple fans) as well as various economizer strategies (return
air versus supply air control and the resulting chiller loading). I am
also interested in detailed chiller modeling, as the load varies from
full economizer to full chiller and the chiller part-load performance is
a key attribute. The chiller supply temperature will be higher than
typical for chilled water coil cooling, so that must be flexible as well.

2) Is there any specialized modeling tool that anyone knows about
that is especially good for such modeling? I would instinctively say
EQuest is NOT good for that, but I may be mistaken. I could make
EnergyPro work, but I do not believe that the cooling tower / chiller
interface is detailed enough using DOE.2.

Your thoughts are appreciated.

Cheers!

--
Robert Wichert P.Eng. LEED AP BD&C
HERS I/II CEPE CEA
BPI CERTIFIED SF/MF GREEN POINT RATER
+1 916 966 9060
FAX +1 916 966 9068

===============================================

RobertWichert's picture
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Robert,

1. EnergyPlus can do this with one proverbial hand tied behind its back. (You, however, will need both hands)

2. I am unaware of a specialized tool.

James V Dirkes II, PE, BEMP, LEED AP

www.buildingperformanceteam.com

Energy Analysis, Commissioning & Training Services

1631 Acacia Drive, Grand Rapids, MI 49504 USA

616 450 8653

James V Dirkes II, PE's picture
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Reputation: 203

Unless I'm missing something here, this seems like a very
straightforward modeling problem. I'm curious why you think that eQUEST
or DOE-2 can't handle it. There are plenty of chiller performance
curves, and you could also create your own if you have data on the
chiller characteristics.

Joe Huang's picture
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Classification: UNCLASSIFIED
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What do you mean by 'accurately'?

Jeurek's picture
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Thanks to all who have replied. This has been very helpful, as always.
I was not aware of the eQUEST option of using DOE-2.3 with data center
additions. This sounds quite well suited to my situation.

Jeff, are you an experienced user of this version with data center
additions? Can you recommend someone who is?

I have posted this, as recommended, to unmethours.com and I will
consider posting it to the eQUEST list as well.

Thanks to all!

Robert Wichert P.Eng. LEED AP BD&C
HERS I/II CEPE CEA
BPI CERTIFIED SF/MF GREEN POINT RATER
+1 916 966 9060
FAX +1 916 966 9068

===============================================

RobertWichert's picture
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Before you jump into DOE2.3, make sure you read DOE23Vol6-NewFeatures. The first section lists the DOE2.2 features not currently included in DOE2.3. For example OA-FROM-SYSTEM is not implemented.

Christopher Jones, P.Eng.
Tel: 416.644.4226 ? Toll Free: 1.888.425.7255 x 527

Chris Jones

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