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NC-v4 EAp2:Minimum energy performance

Data Centre energy model baseline

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Ameet AA
LEEDuser Basic Member
27 thumbs up

Hello,

For a large data centre, I was thinking the baseline should be:

- HVAC: system 8

- CRAC fan power: Ls x 0.0021 + A as per ASHRAE table G3.1.2.9

Is this correct?

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Marcus Sheffer
LEED Fellow
7group / Energy Opportunities
LEEDuser Expert
4454 thumbs up

Wed, 01/23/2019 - 16:20

Sounds right. Table G3.1.2.9 is a part of Section G3.1.2.10 which is how you calculate baseline fan power.
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Ameet AA
LEEDuser Basic Member
27 thumbs up

Mon, 03/11/2019 - 09:07

Thank you Marcus. 1) What about table 6.8.1K? Do I need to use this table, e.g., air conditioner water cooled, for the baseline CRAC fan power? It appears that the actual CRAC equipment SCOP is around 20, much better than 2.40. 2) For baseline chiller, table 6.8.1c mentions only full load and IPLV COP, how do I define the COP at part load conditions? I.e., a typical chiller performance chart gives COP at 100%, 90%, 80%...until 20% part load, how do I decide the baseline COP at all these part load conditions?
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Danilo Ilic
Mechanical Designer
Integral Group
LEEDuser Basic Member
13 thumbs up

Wed, 03/13/2019 - 10:25

Ameet, for the SCOP you are comparing values in IP and SI units most likely. The ASHRAE table gives the SCOP in SI units, that's why the difference is huge. The maximum theoretical (Carnot Cycle) COP value is 8.8 in SI units.
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Marcus Sheffer
LEED Fellow
7group / Energy Opportunities
LEEDuser Expert
4454 thumbs up

Mon, 03/18/2019 - 19:24

1. You will not use that table for the baseline system. 2. You would use a default chiller curve and autosize the system. You generally do not decide the COP at part load conditions. You enter a full load COP and a curve.

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