Meters

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Hello All,

I have two questions about steam/chilled water meters.

1) There is a spot to specify equipment
efficiency -->source to site efficiency. Does this factor affect the
amount of steam/chilled water required for my system? In other words if
I set the efficiency to 1 then the load in the reports is what my
equipment needs to satisfy my conditions. If I set the efficiency to .6
then will my loads will be higher to compensate for losses in
transmission from the plant to my site?

2) My unmet load hours doubled when I removed
the chillers/boilers and replaced them with meters. Does anyone have an
explanation for why this occurs or how I can fix it?

Thanks in advance for your help.

Seth Spangler, LEED(r) AP

Tiger06's picture
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1) DOE reports both a* site* energy use and a *source *energy use
value. Site would be the energy input to your building. Source would
be the energy input to the generating station or district energy
provider. Setting the efficiency to 0.6 would not impact your loads or
any site energy #s. It would increase the *source* energy reported to
take into account the generation efficiency and distribution losses of
the energy provider. Manual has a better explanation.

2) There is a capacity and capacity ratio for the chilled water & steam
meters. Typically the capacity ratio would be 1 so the meter will
deliver whatever the building calls for. You can set these lower to
account for the utility capacity available to your building. If they
are lower, that may account for your unmet loads. It could also be your
pump flow rates, your chilled water temperature and/or your hot water
temperature. How are the hot water & chilled water loops sized --
perhaps fixed #s would be better than sizing ratios. Check SS-R reports
to see which zones are affected by unmet hours to isolate the issue.

Not sure this helps much.

bfountain's picture
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