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Metered Electricity has a negative value

asked 2016-10-26 07:29:27 -0600

updated 2016-10-26 09:03:22 -0600

I'm working on a model of a cold storage (-20C) refrigerated facility and am reporting the Electricity:Facility meter use. When I review it, many of the values are negativeimage description

This does not make sense to me. Am I missing something?

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Do you have any on-site electricity generation?

Archmage gravatar image Archmage  ( 2016-10-26 08:33:09 -0600 )edit

No on-site generation :(

Jim Dirkes gravatar image Jim Dirkes  ( 2016-10-26 08:50:42 -0600 )edit

2 Answers

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answered 2016-10-26 10:11:39 -0600

kwalkerman gravatar image

look at your electrical end-uses on a timestep basis, particularly the refrigeration equipment. What refrigeration equipment setup are you using? I have had issues mixing ZoneHVAC:RefrigerationChillerSet with the simplified system available in Refrigeration:CompressorRack. This was EPlus version 8.4. I have not had the chance to create an error report for it yet.

Also, I've experienced negative electricity use in the past with the water to air heat pump model if my refrigeration curve coefficients were not set up properly. I suspect that you have a refrigeration curve in the wrong place, or one of your coefficients is not correct.

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My bet is on the curves. I copied and pasted from another location and probably got something off by a field. Thank you! I'll check it out.

Jim Dirkes gravatar image Jim Dirkes  ( 2016-10-26 11:47:45 -0600 )edit

you're welcome!

kwalkerman gravatar image kwalkerman  ( 2016-10-26 11:59:52 -0600 )edit

answered 2016-10-26 12:48:31 -0600

I took a look at detailed output for compressor power. I have a problem with one compressor set. Now I'll find it and my first stop is to chart the curve output.

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Asked: 2016-10-26 07:29:27 -0600

Seen: 121 times

Last updated: Oct 26 '16