Utility Meters and SubMeters in eQuest

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Hi guys,
In an effort to break out the electric consumption for the elevators in my building, I assigned that load to a submeter which I then assigned to the main utility meter EM1. This seems to have worked because I can see both meters and their respective consumptions in the PS-B report. Additionally, the ES-D report shows me that the total electric consumption for the building is being accounted for and billed according to my input utility rate. This is all fine and well.

When I look at the BEPU report, however, it only reports the energy consumption of the main utility meter, while ignoring the added consumption from the submetered elevator meter. Since my elevator meter is a submeter to the main electric meter EM1, shouldn't the BEPU report for EM1 show the total consumption of both meters? How do I get the BEPU report to show the total electric consumption? Thanks in advance!

Seun Odukomaiya, EIT, LEED AP

Seun Odukomaiya2's picture
Joined: 2011-09-30
Reputation: 0

Hi Seun,

Hmm... I checked a previous project with sub-metering and did not find
the same discrepancy between BEPU totals and the other reports... EM1's
figures appear inclusive (not exclusive) of the sub-metered energies on
PS-B. I could see that being unintuitive the way it's presented, and
perhaps that's the root of the issue here?

PS-E and PS-F take the PS-B report further - one of those should show
the sum totals for "all electric meters," broken out by energy end-use.
That would seem a good place to start, to ensure all your sub-metered
loads are being modeled and are accounted for. I am seeing BEPU totals
that match, so if you see a mis-match it may be a sign that the
sub-meters aren't correctly assigned to the utility meter (EM1)?

~Nick

NICK CATON, P.E.

Nick-Caton's picture
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Joined: 2011-09-30
Reputation: 605

Hi Seun - I'm sharing my response for others' benefit to understand how sub-meters are documented, I hope you don't mind!

Here are some select excerpts for illustration from your project:

TASK MISC SPACE SPACE HEAT PUMPS VENT REFRIG HT PUMP DOMEST EXT

LIGHTS LIGHTS EQUIP HEATING COOLING REJECT & AUX FANS DISPLAY SUPPLEM HOT WTR USAGE TOTAL

------- ------- ------- ------- ------- ------- ------- ------- ------- ------- ------- ------- --------

EM1 ELECTRICITY

KWH 86385. 0. 167249. 37739. 57318. 0. 15880. 71310. 0. 0. 26146. 5761. 467786.

JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC TOTAL

------- ------- ------- ------- ------- ------- ------- ------- ------- ------- ------- ------- --------

EM1 ELECTRICITY

KWH 40806. 38821. 39184. 39124. 33028. 37465. 40334. 42471. 41722. 37863. 35728. 41242. 467786.

MAX KW 130.3 129.7 143.6 147.2 160.4 144.7 145.1 193.5 179.5 162.2 150.2 129.3 193.5

DAY/HR 16/11 18/11 16/13 17/13 8/13 22/15 22/17 17/13 22/13 13/12 2/13 4/11 8/17

ELEV ELECTRICITY

KWH 2653. 2495. 2868. 2868. 2653. 2868. 2868. 2777. 2744. 2777. 2495. 2868. 32934.

MAX KW 15.4 15.4 15.4 15.4 15.4 15.4 15.4 15.4 15.4 15.4 15.4 15.4 15.4

DAY/HR 2/ 9 2/ 9 2/ 9 1/ 9 1/ 9 1/ 9 1/ 9 3/ 9 1/ 9 1/ 9 2/ 9 1/ 9 1/ 2

TASK MISC SPACE SPACE HEAT PUMPS VENT REFRIG HT PUMP DOMEST EXT

LIGHTS LIGHTS EQUIP HEATING COOLING REJECT & AUX FANS DISPLAY SUPPLEM HOT WTR USAGE TOTAL

------- ------- ------- ------- ------- ------- ------- ------- ------- ------- ------- ------- --------

KWH 86385. 0. 167249. 37739. 57318. 0. 15880. 71310. 0. 0. 26146. 5761. 467786.

MAX KW 28.689 0.000 68.391 17.727 67.449 0.000 5.817 25.761 0.000 0.000 5.208 1.315 193.501

MON/DY 1/ 2 0/ 0 1/ 8 2/ 4 8/17 0/ 0 8/17 8/17 0/ 0 0/ 0 1/ 2 1/ 1 8/17

PEAK ENDUSE 21.709 0.000 68.391 0.000 66.883 0.000 5.817 25.493 0.000 0.000 5.208 0.000

PEAK PCT 11.2 0.0 35.3 0.0 34.6 0.0 3.0 13.2 0.0 0.0 2.7 0.0

This all looks pretty normal to me! Page 127/160 of the "Help ? Tutorials and Reference ? Detailed Simulation Reports Summary.pdf" explains the BEPU report only shows one row for each utility meter. Sub-meters should not show up on that report, if that's what you're getting at.

The totals shown for EM1 (467,786 kWh) are inclusive of your Elevator sub-meter. You can test this by zero-ing out your elevator energy and observing the EM1 totals lowering by approximately 32,934 kWh. In fact, the sum lowers slightly more than that quantity, presumably because electric components of other conditioning equipment serving adjoining spaces are no longer handling the residual heat from the elevator equipment.

Rest assured, nobody should be expecting your elevator sub-meter to show up explicitly on BEPU. Its energies are rolled into the EM1 total. If you need to document the separate metering, PS-B should suffice. If documenting the sub-metered energies distinct from EM1 for LEED or similar, remember to pull the sub-metered quantities from the inclusive totals for EM1.

I will add that this "inclusive" nature of reporting when you have sub-metering defined was not immediately apparent or intuitive for me when I first encountered it... but maybe that was just me =)!

Hope this helps,

~Nick

Nick-Caton's picture
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Joined: 2011-09-30
Reputation: 605

Nick,
Thanks for taking a look at this. I followed your steps and observed the same behavior. This gives me confidence that the "EM1" Meter is in fact accounting for all submeters. I guess my confusion came from not completely understanding what exactly was being reported in the BEPU report. I now have what I need to respond to a USGBC comment about why there are discrepancies in the reports. Again, thanks for all the help!

Seun Odukomaiya, EIT, LEED AP 

Seun Odukomaiya2's picture
Joined: 2011-09-30
Reputation: 0