Anyone have any ingenious ways to heat water in an Above Ground?

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CJadamec said:
Nope between the pool being in the full sun along with the panels the water temp increases by 2 degrees an hour.
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OK. I understood from your previous post the solar panels were themselves adding 2 degrees per hour. If it is 2 degrees per hour INCLUDING the pool, then that is quite different.

Your pool's surface area is about 42 square meters. Your panels add another 11 square meters. A total of 53 square meters would still be a bit shy of producing the 64kWh needed for a 2 degree rise (given typical pool and panel efficiencies) but is possible given measurement errors, incident radiation effects, altitude, geography etc.

It's simply not possible for the solar panels alone to be adding that much. Not even if they were mounted on the Space Station. That's what caught my eye.
 
Zrock said:
Exactly... Last year i just took a 50 ft roll of black piping and tossed it on the ground and used one of my old pumps to run it.. It worked for what i needed and made it more comfortable to use the pool.
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So 2 square feet of solar collector assuming 0.5 inch tubing. At 100% efficiency this would add about 200 Watts per hour in peak sun (see my post above).

But your tubing is no where near 100% efficiency. The ratio of surface area to volume for half inch tubing results in a very poor heat exchange coefficient. Round tubing is not optimum cross section. Heat loss to the ground and air reduces the efficiency further. Thermal resistance of the tubing walls limits heat transfer. Etc, etc. You would be doing very well to achieve 25% efficiency. That would be less than 50 watts of heat added per hour. It's not enough to make a meaningful difference even if you were swimming in a bath tub. If you noticed a heat gain, it didn't come from your black tubes laying on the ground.
 
I have enjoyed reading this thread and everyone`s input. I have one question for both solar panels and polyethylene pipe.

If water in either system was allowed to heat not moving then circulate through pool, then stop again allowed to heat again then circulate.

The reason I`m curious our 100’ water hose rolled when full of water in the sun is very hot I`ll have to let it run all heated water out before I can have a cool drink of water from our well.

Also this 100’ of water will heat up fairly quick at 2:50pm central time I checked temperature of water straight out of hose it was 113 degrees.
 
Stopping the water and letting it heat up and then restarting is less efficient than continuous circulation at the lowest possible temperature. This is because the sun's radiant heat transfer decreases (ie water absorbs less energy from sun) and heat losses increase (ie water loses more heat to the environment) as water temperature rises.

The hot hose example is how a lot of DIYers get in trouble. It is not enough to say it's "full of hot water" and "it heats fairly quickly". One has to be precise to know exactly how much energy is being transferred into the water. Exactly how much water is heated to 113 degrees and how long did it take? Measure that and you'll find the amount of energy being absorbed is significantly less than a good solar panel. It's all about calories, joules, watts, btu's and their rates. In the end, there just isn't enough 113 degree water being made often enough to make a worthwhile difference for a pool. It's not that it can't work, it's that it requires gynormously long hoses (!) and even then it's not very efficient so a good solar panel could do the same job in less area.
 
Solar covers do work. I place my cover on a night (in June and September only) and now have a heat pump. The temperature drop is only a max of 2 degrees, even with temperatures that drop in the 60's. Within 2 hours, in the a.m., the pool heats up to the normal level, which is about 85* with the heater. I really think that the heater and cover are essential for keeping warm at a reasonable temperature. The difference between the heat pump (water running through) at 85 degrees and off, vs. the first 6" of the surface water is 5 degrees. Today, the surface was around 90 degrees. So trapping most of the heat at night is what makes most sense, whether or not one has a heater, then removing the cover during peak sun hours.

One would think that considering the surface has a 4-5* difference that main drains should not be used and only surface water should be pulled away through the filter and back to the pool, which is another 12" down (somewhere around there), thereby creating a nice cycle, especially when the sun is in your favor. All these gimmicks that are sold do not work. Solar panels do work, but you need a lot of them on a roof to make any type of difference.
 
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