HP Supp Demand

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Hi All,

I have a question regarding the kW demand reporting for HP supplemental
heat. There is an issue where the kW demand for Space Heat and HP Supp do
not seem to match up with the kWh usage. For example, in January it is
showing 0 kW demand for Space Heat, but the usage is 68,000 kWh. Also, the
kW demand for HP Supp is very high. Has anyone else had this issue? I am
concerned because it has generated a comment from a reviewer. See the
screenshots below:

Thank you!

*Mike Campbell, E.I.T., LEED AP O+M*

MikeSSC's picture
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Joined: 2012-04-23
Reputation: 1

Look up at what time the demand is recorded for (the time should be in the
detailed report - PS-B I think). It is possible that the heating is not ON
at that time, so the demand is zero.
Hope this helps.
-Rohini

R B's picture
R B
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Joined: 2011-09-30
Reputation: 4

I think I understand. So these tables are likely showing the demand for
each end use at the building?s peak demand? And not necessarily the peak
demand for each end use by itself?

*Mike Campbell, E.I.T., LEED AP O+M*

*From:* R B [mailto:slv3sat at gmail.com]
*Sent:* Tuesday, January 07, 2014 10:32 AM
*To:* Michael Campbell
*Cc:* eQUEST Users List
*Subject:* Re: [Equest-users] HP Supp Demand

Look up at what time the demand is recorded for (the time should be in the
detailed report - PS-B I think). It is possible that the heating is not ON
at that time, so the demand is zero.

Hope this helps.

-Rohini

MikeSSC's picture
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Joined: 2012-04-23
Reputation: 1

Yes. Peak demand by end-use is in some other report - I think the one that
gives the energy usage by meter. I always look at the reports in the output
file and have never looked at the eQuest generated graphs/tables - so can't
say which actual report it is using.
-Rohini

R B's picture
R B
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Joined: 2011-09-30
Reputation: 4

PS-F reports will give you the peak demand by end-use by meter. You should check that to confirm your peak kWs for heating.

John Grando BEMP | CEM | LEED AP BD+C

Grando, John's picture
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Joined: 2011-09-30
Reputation: 0

Thank you, John. I reviewed this report and compared my baseline to
proposed. For some reason, the HP Supp demand for my proposed is much
higher than my baseline case. The only thing that I changed for the heat
pumps is the efficiency. Any ideas on why this might be? I have the same
sequence of operations, with HP Supp starting at 40F and taking over 100%
at 5F. My files are attached if anyone has time to take a quick look.

Thanks,

*Mike Campbell, E.I.T., LEED AP O+M*

*From:* equest-users-bounces at lists.onebuilding.org [mailto:
equest-users-bounces at lists.onebuilding.org] *On Behalf Of *Grando, John
*Sent:* Tuesday, January 07, 2014 11:12 AM
*To:* equest-users at lists.onebuilding.org
*Subject:* Re: [Equest-users] HP Supp Demand

PS-F reports will give you the peak demand by end-use by meter. You should
check that to confirm your peak kWs for heating.

*John Grando BEMP | CEM | LEED AP BD+C* |

MikeSSC's picture
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Joined: 2012-04-23
Reputation: 1

Your infiltration rates are not the same. Check the LS-C report. The peak infiltration in your baseline is 443 KBTU/HR on Jan 25th 7 am and your design is 1656 KBTU/HR on Jan 24th at 6 am. That seems to be your problem for why there is so much supplemental heat.

John Grando BEMP | CEM | LEED AP BD+C

Grando, John's picture
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John, thank you for checking into this! Very much appreciated.

*Mike Campbell, E.I.T., LEED AP O+M*

*From:* equest-users-bounces at lists.onebuilding.org [mailto:
equest-users-bounces at lists.onebuilding.org] *On Behalf Of *Grando, John
*Sent:* Tuesday, January 07, 2014 11:54 AM
*To:* equest-users at lists.onebuilding.org
*Subject:* Re: [Equest-users] HP Supp Demand

Your infiltration rates are not the same. Check the LS-C report. The peak
infiltration in your baseline is 443 KBTU/HR on Jan 25th 7 am and your
design is 1656 KBTU/HR on Jan 24th at 6 am. That seems to be your problem
for why there is so much supplemental heat.

*John Grando BEMP | CEM | LEED AP BD+C* |

MikeSSC's picture
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Joined: 2012-04-23
Reputation: 1

No problem,

For the future, to avoid these kinds of headaches you can do a quick 'diff' of the two .inp files which ends up telling you a lot of information in a short amount of time.

http://en.wikipedia.org/wiki/Comparison_of_file_comparison_tools

John Grando BEMP | CEM | LEED AP BD+C

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