I cannot comment on Energy+. However, as far as eQUEST, I've modeled a
natatorium (indoor pool) including the latent load. In one of the
ASHRAE books, there's a methodology for determining the latent loads of
a pool as a function of activity, water temperature, and I believe a few
other factors. I ran through these calculations and inputted this load
into the "Internal Energy Sources" under the Equipment internal gains
tab. I created a schedule based on when the proposed pool cover would
be off (pool in use), and called it a "process" load. I believe I set
the Latent HG ratio to 1.0 and Sensible to 0.

The results of my model seemed to be reasonable.

Maybe with this methodology, it might allow you figure something out
with Energy+; otherwise, eQUEST may be your best, closest approximation,
for this project.

That's also the methodology I followed for a recent project in eQuest.

You can find an equation for the evaporation rate in the ASHRAE
Applications Handbook. Another source is
http://www.rlmartin.com/rspec/whatis/index.html.

I don't know if anyone has used it for modeling swimming pools, but
EnergyPlus does provide a way of specifying water uses. If you know and
can schedule the water temperature and evaporation rates, that can be
used as input for a Water Use Equipment object with a latent fraction of
1.0. The modeling accounts for both sensible and latent effects of
evaporation related to cooling, zone humidity, integrated interactions
with HVAC, etc.

My understanding (from some long-forgotten reference, possibly authoritative, possibly not) has always been that the evaporative cooling effect accrues to the pool itself and the pool heater offsets it, and I have not modeled as a cooling load in/to the space. But I could imagine that part of that evaporation does cool the space.

You'll find useful information about modeling this in the paper:

Haberl, J., Claridge, D. 1985. "Retrofit Energy Studies of a Recreation
Center," ASHRAE Transactions-Research, Vol. 91, Pt. 2, pp. 1421 - 1433
(June).

There have also been a number of papers written on calculating the
incoming/outgoing heat transfer from the pool surface, including one by
Francis DeWinter (1980s, Atlas Corp.), and there is a useful reference
method in the FCHART manual.

I cannot comment on Energy+. However, as far as eQUEST, I've modeled a

natatorium (indoor pool) including the latent load. In one of the

ASHRAE books, there's a methodology for determining the latent loads of

a pool as a function of activity, water temperature, and I believe a few

other factors. I ran through these calculations and inputted this load

into the "Internal Energy Sources" under the Equipment internal gains

tab. I created a schedule based on when the proposed pool cover would

be off (pool in use), and called it a "process" load. I believe I set

the Latent HG ratio to 1.0 and Sensible to 0.

The results of my model seemed to be reasonable.

Maybe with this methodology, it might allow you figure something out

with Energy+; otherwise, eQUEST may be your best, closest approximation,

for this project.

Dusko,

That's also the methodology I followed for a recent project in eQuest.

You can find an equation for the evaporation rate in the ASHRAE

Applications Handbook. Another source is

http://www.rlmartin.com/rspec/whatis/index.html.

Hope this helps.

______________

Demba Ndiaye

The evaporation has a cooling effect that needs to be accounted for with

a sensible source load in the model.

Doug Maddox

I don't know if anyone has used it for modeling swimming pools, but

EnergyPlus does provide a way of specifying water uses. If you know and

can schedule the water temperature and evaporation rates, that can be

used as input for a Water Use Equipment object with a latent fraction of

1.0. The modeling accounts for both sensible and latent effects of

evaporation related to cooling, zone humidity, integrated interactions

with HVAC, etc.

My understanding (from some long-forgotten reference, possibly authoritative, possibly not) has always been that the evaporative cooling effect accrues to the pool itself and the pool heater offsets it, and I have not modeled as a cooling load in/to the space. But I could imagine that part of that evaporation does cool the space.

Fred Porter

I'm not sure how it breaks down between pool load and air load, but I

think it is part of the building heating load in either case.

Doug Maddox

FYI

You'll find useful information about modeling this in the paper:

Haberl, J., Claridge, D. 1985. "Retrofit Energy Studies of a Recreation

Center," ASHRAE Transactions-Research, Vol. 91, Pt. 2, pp. 1421 - 1433

(June).

There have also been a number of papers written on calculating the

incoming/outgoing heat transfer from the pool surface, including one by

Francis DeWinter (1980s, Atlas Corp.), and there is a useful reference

method in the FCHART manual.

Jeff S. Haberl, Ph.D.,P.E