I just dropped the price of
the permaculture playing cards
for a wee bit.

 

 

uses include:
- infecting brains with permaculture
- convincing folks that you are not crazy
- gift giving obligations
- stocking stuffer
- gambling distraction
- an hour or two of reading
- find the needle
- find the 26 hidden names

clickity-click-click

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Roof mounted solar heater[s] for a pool  RSS feed

 
Darryl Roederer
Posts: 39
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We put the cover on the pool this weekend, which really takes the fun out of having a pool. Even tho I'm in Louisville Ky, we can only get about 4 months of enjoyment out of it before it gets too cold to use. I'd like to install a solar setup on top of the garage in hopes that we can extend our season into something closer to 5 or even 6 months. Or at the very least, warm it up enough to make it a little more relaxing during the peak of summer.

I've found a couple videos on youtube of some solar water heaters that look as if they might work, where you take 100 feet of 1/2" black water tube, and coil it into a spiral on top of a sheet of ply-wood. By my rough math, I've got room for 4 of these on top of my 1 car garage/workshop.

My question then becomes how do I get the maximum benefit out of such a system? Should I plumb it so that there's only one intake tube and one outlet, and 100% of the water flows thru all 4 solar collectors? Or should I parallel the system so I have 4 independent collectors?

My thinking is that if I run it in series, I'll reach a point of diminishing returns after 100 or 200 feet, and the remainder of the system wont serve to heat the water any further. On the other hand, I'm not sure I'll gain an appreciable temperature gain out of a single 100 foot run.

Naturally, I realize that [slower] flow rates will allow the water to absorb more heat, and whatever system I end up using will require some testing to get my flow formula just right for maximum efficiency, but I'd really appreciate hearing from someone with some hands on experience in helping me design the most efficient system possible.
solar_pool_heater_diy_photo4.jpg
[Thumbnail for solar_pool_heater_diy_photo4.jpg]
 
Tim Williams
Posts: 8
Location: North Alabama
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Darryl,

I don't think the black irrigation tubing used can handle the water inside freezing, which means the entire coil must be drained in the fall. I don't see a way to do this without disassembling the whole thing. I've been thinking of a plan to use a grid of black tubing mounted at an angle so all the pipes can drain to a low point. Add a vent at the high point and a drain at the low point, and you can now easily drain the system. The problem is the Tees and elbows significantly add to the cost.

The other solution I have seen is to use a flexible tubing that can handle freezing. I have not seen pricing, but for comparison, I would get a quote from
http://www.h2otsun.com/index.html

Happy Swimming!
 
Acetylsalicylic acid is aspirin. This could be handy too:
Permaculture Playing Cards by Paul Wheaton and Alexander Ojeda
https://permies.com/wiki/57503/digital-market/digital-market/Permaculture-Playing-Cards-Paul-Wheaton
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