Well my parents have a 40'x20' pool and the thing just got opened. It's in the sun most of the day, but takes quite a long time to heat up. I was thinking and my mother and I discussed me making a solar powered pool heater because it would cost way to much to get something that pumps water around and heat it up. For this project I am thinking that the parts I would need would be :

A solar panel obviously
1 Car Battery
1 Regulator
1 Large fishtank heater
1 DC to AC power inverter
Something square to hold it all up without too much shaking.

I was thinking of mounting all of this on an innertube. A solar Panel would not weigh much, just a few pounds. The fishtank heater wouldnt add much weight as it will be in the water and the inverter will weigh a few pounds. I am looking at This solar panel. The heater I am looking at is this right here. since the solar panel has an adapter for a cigarette lighter which is what the Power inverter hooks into, would it be possible that I hook the inverter straight into the solar panel and then plug the fish tank heater right into the inverter, cutting out a battery from being used? Here is the power inverter that I would like to use. Would I need a battery that the solar panel would charge first so that the wattage output was greater then 20Watts and only 12 Volts? The fishtank heater I am looking at is pretty heavy duty being 500W and 4.8Amps. Also, would it be possible to charge the battery while I am using it, or would that require having 2 batteries?

If I need 2 batteries, I am fine with that. I am thinking I would need a regulator also, what would I need to look for, besides being 12 Volts and around (I think) 15 Amp maximum input on car batteries, what would I need to look for in a regulator? I know the input needs to be from a cigarette lighter or from clamps. The regulator I am looking at is here. It is made for automotive batteries and If they make inverters that work with peaks of 1600Ws, then the battery should be able to output that much. I have also seen dual terminal batteries, would I be able to charge them while in use, or would i still need 2 separate batteries?

If you want economical, get 1" ABS soft pipe and make flat coils. Use a small pump to circulate the water through the coil. Use the solar cells to run the pump if you want to keep it completely off the grid.

Many years ago, the first boss I had had a setup like this. His coil array was 20' x 80' ( he had 10 acres, space no problem ). In Southern Ontario we don't get much sun even compared to foggy London, but by February he had the pool to 80F.

I have looked into this type of system before, but I want something that I can simply pick up out of the pool and put into storage without assembly and disassembly. Wasnt that a very popular type of water heater for homes in the 1970's out in california and the desert areas? Also, I do not have much space for making a piping system for this. The thing I planon making is going to be a small little package that wont take much room. To have pipes running would require more space then I am allowed. Thank you though

This post has been edited by ferrari12508: 26 May, 2008 - 06:00 PM

Another idea, although a bit "green", but one that has solid basis, is using a compost heater. Now, idea is rather simple. Compost heaps (where you'd put grass clippings, or other organic things) have a usual heat of 135 degree F. What people have done before is put coils of copper tubing in the middle of a pile and cold water goes in one side, and hot water our the other. The only thing you would need would be a pump to pump the water through (from the pool), through the pipe and put it back into the pool. At one side you could have a thermometer to make sure the water does not cool down too much (set a threshhold to turn off at a certain heat). Takes about 15 minutes for the compost to reheat itself. Not only can you make compost, but it will heat your pool with nothing more than a method to pump the water into it. Took this idea from a shower I saw built...seriously...good supply of hot water, and quick recharge rate.

Maybe just a small unit on one 4x8 sheet of plywood with the pump mounted. Roll it away when guest come over.

I like Akelo's idea but I think it would be hard to pick up the compost and move it quickly

Well, what if you used the dolly concept of moving it. Roll it over, it has piping that extends out and at an angle to put into the water, and just tilt, roll over, and put into the water (would need to have the piping be adjustable...but one input, one output pipe and it's all good ...doesn't have to be copper, could be pcv with copper on the inside . Maybe even a basic hand pump to start sucking in the water.

To expand on Akelo's idea on compost; compost in a can say pint or gallon paint can that floats around in the pool. a little solar cell on top to run the pump and a timer with wi-fi to connect to your computer to tell you the compost is done and no heat is being produced.
Pint size for kiddy pools and gallon ( or 3.78L ) for larger pools. Easily removable and transportable. Buy a dozen for big pools!

Together with that, you could also put your pump's pipe in a zig-zag shape on for example your garden house. The sun'll shine on it and the water'll get extra heated!