[Equest-users] pool heating baseline system

[Edward Allen]

It's unfortunate that I've caught onto this discussion late, as it is right in the middle of a current tax rebate modeling project I'm working on.

My query (more of a confirmation really) is how are you all handling the latent load from the pool?  I've input it as a process load, 100% latent.

How do you account for the thermal mass of the pool water?  Latent heat is handled above.  What about sensible effects?  I've entered the pool water in the "Contents" tab covering 80% of the floor area with 500 lb/ft2.

Also, what is the group's read on the space conditions to be maintained in the proposed vs. budget cases?  I've modeled them identical in both:  85 deg F, 55% RH per ASHRAE recommendations.  It doesn't show up on any building meters, so wouldn't be double counted as service water as discussed below and misc equip.

Finally, what system is appropriate for the budget case model?  I've just let the compliance tool select the system, and it chose PIU - the same as the none pool zones in the building.

Thanks,
Edward M. Allen, PE, CEM
LONG Energy Solutions
Technology for Better Buildings
775.657.9180 office  720.217.1356 mobile  775.657.9180 fax
eallen at long.com
        http://www.long.com<http://www.long.com/>

________________________________
From: equest-users-bounces at lists.onebuilding.org [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Nick Caton
Sent: Tuesday, January 25, 2011 8:38 PM
To: Dahlstrom, Aaron; Mirza Sajjal; Pasha Korber-Gonzalez
Cc: equest-users at lists.onebuilding.org
Subject: Re: [Equest-users] pool heating baseline system

Well I've given a little extra effort =)...  I've flip-flopped a few times, and now feel confident of the following:


1.       This query boils down to this paraphrase:  Does Table G3.1.11 (Service Hot-Water Systems) or G3.1.12 (Receptacle and other loads) apply to pool water heating?

2.       Definitions Section 3:  service water heating - heating water for domestic or commercial purposes other than space heating and process requirements.

3.       We can strike out space heating, so we can conclude pool water heating is either a process energy OR service water heating... it cannot be both.

4.       GRAMMAR LESSON FOR ANSI/ASHRAE/IESNA - WOOHOO!

a.       Per the definition Mirza transcribed below, pool heating is pretty clearly "...maintaining comfort and amenities for the occupants of a building."

b.      So (clearly) pool heating energy simply [IS/IS NOT] a process energy, and therefore [IS/IS NOT] a process load.  Read that whole definition from both angles, and you can see this definition was not crafted by an English teacher!  This doesn't make anyone's life easier, but I maintain this definition can be read either way.

5.       Where the glossary fails us, we have to look elsewhere.  Fortunately, this seems much more clear:  Pool water heating must be a form of service water heating, otherwise it wouldn't be explicitly addressed multiples times under Section 7 "SERVICE WATER HEATING."  Clever eh =)?

In conclusion, within the context of "do I model pool energy under the requirements of Table G3.1.11 or G3.1.12?"  The answer is clearly G3.1.11 because it is a variety of service hot-water system.  To extend the argument, pool water heating is NOT a process energy and so should NOT be modeled as such (equally in both models), even if it would save time (bummer!).  I might suggest documenting the pool heating consumptions/demands separately from domestic water heating consumption in the LEED template.

Table G3.1.11 is agreeably crystal-clear in requiring you to use straight electric resistance heating for the baseline pool heating system.

If LEED was an episode of "America's Next Top Model," and the 90.1-2007 steering committee were the judges, heat-pump pool heating strategies would be rated "Platinum-Sexy."

I might also watch more TV... kinda sad...  ^_^

~Nick


[cid:489575314 at 22072009-0ABB]

NICK CATON, E.I.T.
PROJECT ENGINEER
Smith & Boucher Engineers
25501 west valley parkway
olathe ks 66061
direct 913 344.0036
fax 913 345.0617
www.smithboucher.com

From: Dahlstrom, Aaron [mailto:ADahlstrom at in-posse.com]
Sent: Tuesday, January 25, 2011 7:59 PM
To: Mirza Sajjal; Nick Caton; Pasha Korber-Gonzalez
Cc: equest-users at lists.onebuilding.org
Subject: RE: [Equest-users] pool heating baseline system

Mirza -

I agree with your logic about the intent of the standard and its definition of non-regulated process. This may be a prejudice that harkens back to LEED v2.1, but if I see a regulation in 90.1 for efficiency, I assume that ASHRAE intended to "regulate" the energy use of that category, and thus it falls on the non-process side of things. While there may be circumstances where "pool heating" might seem more like a process load (eg freeze protection for an outdoor decorative fountain in a cold climate?), it seems like the intent of 90.1 was to regulate pool heating energy usage for a large proportion of typical pool installations.

I think your question re: how to interpret the wording of G3.1.11 is important.
On the face of App G, the standard appears to reward heat pump pool heaters, by allowing them to compare to straight resistance heat in the baseline.
In my admittedly limited experience, I haven't seen an electric resistance pool heater, so I share your reservations about making a false comparison. (then again ... http://www.little-giant.com/water-heating-products/pool-spa-heaters/electric-pool-spa-heaters.html)

If we can't find help for you on this list, an "unofficial interpretation" by the 90.1 Standards Committee might be the way to go.
(Maybe Nick could even slip the question in when he's out at the winter meetings this week ;) ?)

Aaron Dahlstrom , PE, LEED(r) AP
In Posse - A subsidiary of AKF| 1500 Walnut Street, Suite 1414, Philadelphia, PA 19102
d: 215-282-6753| m: 267-507-5470| In Posse: 215-282-6800| AKF: 215-735-7290
e: ADahlstrom at in-posse.com | in posse web: www.in-posse.com<http://www.in-posse.com/> | akf web: www.akfgroup.com<http://www.akfgroup.com/>



From: equest-users-bounces at lists.onebuilding.org [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Mirza Sajjal
Sent: Tuesday, January 25, 2011 7:36 PM
To: Nick Caton; Pasha Korber-Gonzalez
Cc: equest-users at lists.onebuilding.org
Subject: Re: [Equest-users] pool heating baseline system

Pasha/Nick,
Thanks for the response.

I would assume pool space conditioning and pool water heating are not process energy (?) as 90.1 defines process energy as:
"Energy consumed in support of a manufacturing, industrial, or commercial process other than conditioning spaces and maintaining comfort and amenities for the occupants of a building."

I did notice the baseline efficiency for heat pump pool heaters in table 7, but was trying to figure out if the system types had to be the same in baseline and proposed since App. G mentions only energy source: "Where the energy source is electricity, the heating method shall be electric resistance."

Considering the savings are significant when using electric resistance pool heating in the baseline, I want to prevent any issues I may encounter during the LEED review process since the reviewer may have a different interpretation/opinion.

Mirza

From: equest-users-bounces at lists.onebuilding.org [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Nick Caton
Sent: Tuesday, January 25, 2011 7:05 PM
To: Pasha Korber-Gonzalez; Mirza Sajjal
Cc: equest-users at lists.onebuilding.org
Subject: Re: [Equest-users] pool heating baseline system

Whether or not it's a process load may come down to semantics (I think you can make a case either way if you reference the 90.1 glossary terms - see 'process load' and 'process energy'), but I think it's moot in a broad sense...

If there weren't significant savings to be credited, then I'd probably try to call it a process load and make each model identical.  That would be the simplest and most time efficient approach.

However, if there are major savings using heatpumps relative to "conventional" heating means, then even if it is a "process load" I would pursue modeling them differently as an exceptional calculation.

Oh, and 90.1 does define a baseline efficiency (COP) for heat pump pool heating equipment:  Take a closer look the table in chapter 7.  You might also review the prescriptive pool requirements for other means to differentiate the proposed design other than in heating efficiency.

Best of luck!

~Nick

[cid:489575314 at 22072009-0ABB]

NICK CATON, E.I.T.
PROJECT ENGINEER
Smith & Boucher Engineers
25501 west valley parkway
olathe ks 66061
direct 913 344.0036
fax 913 345.0617
www.smithboucher.com

From: equest-users-bounces at lists.onebuilding.org [mailto:equest-users-bounces at lists.onebuilding.org] On Behalf Of Pasha Korber-Gonzalez
Sent: Tuesday, January 25, 2011 4:50 PM
To: Mirza Sajjal
Cc: equest-users at lists.onebuilding.org
Subject: Re: [Equest-users] pool heating baseline system

Isn't the pool heating system considered as a process load for 90.1 since it has no effect on the overall building design?  It would be exactly the same in the baseline as it is for the proposed case.

...just a thought, although I haven't run into this scenario with any of my sim projects.

Pasha


On Tue, Jan 25, 2011 at 3:19 PM, Mirza Sajjal <ms2995 at gmail.com<mailto:ms2995 at gmail.com>> wrote:
Can anyone tell me what the baseline pool heating system should be if the design calls for heat pumps? Per App. G Table G3.1.11 the requirement is that the energy source be the same, in this case electricity. Can we model the baseline as electric water heaters or should the system type (heat pumps) also remain the same in the baseline since electric resistance pool heating is unconventional? Theres a huge energy savings difference between the two baselines and was wondering how others have modeled this in terms of LEED.
Your opinion and insight is much appreciated.
Thanks in advance for any response.

Mirza

_______________________________________________
Equest-users mailing list
http://lists.onebuilding.org/listinfo.cgi/equest-users-onebuilding.org
To unsubscribe from this mailing list send  a blank message to EQUEST-USERS-UNSUBSCRIBE at ONEBUILDING.ORG<mailto:EQUEST-USERS-UNSUBSCRIBE at ONEBUILDING.ORG>



This message has been scanned by MailController<http://www.mailcontroller.altohiway.com/>.

This e-mail may contain information that is confidential, privileged or otherwise protected from disclosure. If you are not an intended recipient of this e-mail, do not duplicate or redistribute it by any means. Please delete it and any attachments and notify the sender that you have received it in error. Unintended recipients are prohibited from taking action on the basis of information in this e-mail. E-mail messages may contain computer viruses or other defects, may not be accurately replicated on other systems, or may be intercepted, deleted or interfered without the knowledge of the sender or the intended recipient. If you are not comfortable with the risks associated with e-mail messages, you may decide not to use e-mail to communicate with In Posse.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20110126/13ac6508/attachment-0001.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: image001.jpg
Type: image/jpeg
Size: 1459 bytes
Desc: image001.jpg
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20110126/13ac6508/attachment-0001.jpg>