Question:
I live in central Texas and want to heat a yet-to-be-built 12' X 28' X 4.5'
> exercise pool for year around use. The water temperature needs to be about
> 80 degrees F. The pool would be used about 1 1/2 hours per day, preferably
> early in the morning. I am having difficultly getting reliable information
> on the most cost effective way to heat the pool. The people I have talked to
> have a vested interest in the products they sale. Natural gas and
> electricity are available as well as adequate roof area for solar heat. Any
> unbiased help would be appreciated.
Answer:
Here are some random thoguhts that will hopefully help with the
process.
The cost of heat (electirc vs gas) is dpeend on the $/ kwatt-hr & the
$/therm in your area.
Gas is typically cheaper than electric
Your exercise pool will hold ~11,000 gallons. ~92,000 lbs
The sizing of your heating system will depend on local day to day
weather conditions (I have no idea of the local weather in your area)
I do know that keeping a pool at 80F in SoCal year round would cost a
LOT, you would need heat in the winter and the summer. The heat losses
to the air & gorund would be very large.
I had a small (~500 gal) above ground spa, well insulated, electric
heat. I kept it turned down during the day but heated it up (about an
hour or so) to spa temperature. I figured it only cost about $20 or
$30 per month.
You've got a much larger mass of water so you need a very large
capacity heater to bring the temp up very quickly. An 100,000 BTU/hr
heater would be able to raise you pool 1 deg F per hr. A LARGE gas
heater (400,000 btu / hr) would be able to heat the pool faster.
So conceivably you could yo-yo the water temp on a daily basis; bring
the temp up for use, then turn the heater off & let the water cool
naturally; repeat the process every morning (heater on a timer).
