James,

There are CIRs related to this for NC v2.2 (if you are using v3 you might have to submit your own CIR). Look up the following ruling dates; 2/26/2008, 5/27/2008, and 2/3/2009. The gist of it is that the baseline system serving the pool has to be the same type and have the same controls but you can account for mechanical system energy savings via an exceptional calculation method assuming that you can prove that the proposed design goes beyond what is typically done for the application. In the project that I worked with pool units, I had both sensible energy recovery and hot gas bypass as exceptional calculation method energy savings.

Good luck,

Alex Chapin

Date: Fri, 25 Jun 2010 14:16:09 -0400
From: "James V Dirkes II, PE"
To:
Subject: [Bldg-sim] LEED, Process energy and pools
Message-ID: <005701cb1492$7fdf4330$7f9dc990$@net>
Content-Type: text/plain; charset="us-ascii"

Dear Bldg-Sim community,

I've just completed a lovely, accurate, comprehensive building energy model (in Energy Plus) which contains an indoor swimming pool. The building is about 100,000 square feet and the pool area is about 10% of that total.

At the end of the year, the heating, cooling, fans and pumps associated with the pool have consumed 70% of the total building energy! I was rather surprised. I expected it to be a large percentage, but not THAT large!
This, by the way, is the result when using a specialty pool HVAC unit which recovers and re-uses most of the DX cooling energy and thus greatly reduces the pool energy total.

As far as I can tell, ALL of the pool-related energy is considered by ASHRAE
90.1 and LEED to be "process" energy. Since "process" energy must be identical in both the baseline and proposed models, the rest of the building must accomplish the entire savings . which is pretty darn difficult (impossible, really) if "process" is too large a percentage.

Have any of you successfully modeled a building with a pool and also received LEED certification? If so, can you suggest what I might be missing?

Thanks in advance.

BPT BizCard_RGB_0507

Quid est hoc ad aeternitatem?