Heating Options

I am building a new 13,500 gallon in-ground concrete pool. I didn't purchase a heater for the pool because I didn't know what would be the best option.

The pool will be on the north side of the house under a screen enclosure. Half of the pool will have direct sun in the afternoon for about 3 hours - otherwise it will always be in the shade.

We do not have natural gas, but we will have a tank for the gas spa heater - I don't want to go propane on the pool as it's too much $$.

So we are stuck with a heat pump or solar. They cost about the same to install. I would just go with the solar - but we can only place the panels on the north side of the house - will they work? Do they damage the roof (shingles)? With the heat pump my electric bill will be REALLY high...

Any suggestions??

What are your goals for heating the pool? Do you want the pool to be 85 year round every single day? In your location the heat pump as well as solar are both good options. You said you can only put the panels on the North side of the roof. Is your roof pitch steep or shallow, shallow would be better with a northfacing panel, you will have to increase the number of the panels as opposed to a south facing installation. I can not comment on what it will do to your roof but it must not be that bad as many houses use them. With respect to the heat pump they work best with an outdoor temp. above 65 degrees, they CRANK out much more heat when the outdoor temp starts to hit the 80's. I have a heat pump up hear in PA and love the thing but we mainly use it to extend the season and during the summer keep the pool at 85 degress where the wife likes it. It does not cost me more than $150/month to do that and run the pumps.

Really the goal would be able to use the pool 10 months out of the year. March-Dec. Since even in the coldest months the days are in the upper 60's and the nights are in the 50's. I don't expect to be able to swim when it's less than 65 outside (I'd freeze just going outside in a swimsuit).

I would like the pool to be in the lower 80's in the spring/fall so that it is usable. When you spend that much money you want to use it.

The pitch on the roof is low (no snow here). So maybe that is in my favor.

Is it true that the heat pump must be on all the time b/c it will take like 12 hours to heat the pool otherwise? The days already are in the high 90's and the nights in the upper 60's.

For the most part the heat pump is left on because it takes quite a while for the heatpump to bring up the water temp most are less than 100,000 BTU/hr as opposed to gas heater 400,000 BTU/hr. You can make the system more efficient by having the heatpump run during the warm part of the day like 11:00 am to 7:00 PM. I do this by having my main pump on a timer for those times plus an hour before and after so I have 10 hours filtering time. The heatpump won't run unless there is flow in the pipes so this works pretty well. A cover really helps with nightime losses.

Aqua Cal Heat Pumps is a sister company of AutoPilot Systems Inc.
Heat Pumps are designed to maintain heat. The use of a solar blanket, liquid blanket, or no blanket will affect the amount heat lost overnight. The fact is that solar is not a reliable souce of heat, although when it is sunny out, you can generate alot of "free" heat. However, on most cloudy days, you will not be able to generate any heat. A heat pump will continue to produce some heat. Remember, you're only putting back in what was lost overnight.

You can calculate how long a heat pump will need to run, based upon the gallons of water, the desired temperature (or rather, the desired temperature rise), and btu output of the heat pump. What this means is that you should look at the btu output of the heat pump you are interested in. Also, look at the COP of the heat pump, as this has to do with the efficiency of the heat pump. Like an Air Conditioners' SEER rating, Heat Pumps use COP. Anything above 5.0 COP is good efficiency. The higher, the better.

If you provide the gallons, desired temp, and heat pump BTUs, I can calculate how many hours your pump will need to be operated in order to maintain your water temperature.

If costs are similar, you'll have more reliable heat with a heat pump, without dependency on sunny days.
How many cloudy, partly cloudy days do we have in Florida? I'm in Ft Lauderdale, so I know how many days the sun is hiding..your weather is not much different in the Orlando area.

Hope this helps