solar water heater from sodapop cans

[ajccmc]

I have remote cabin and have placed pex pipe stapled up to the floor with AL plates made from flashing.  I plan to create a solar storage unit from water contained in some form of tank likely 600-1000 gallons of it.  To heat the water I'll need some sort of collector.

I have seen a number of articles on building solar hot air collectors from stacked pop cans. So I have been thinking this might work for water also.

The thought is I'll leave the tops on and drill/punch a 1/4" to 3/8" hole in the bottoms. Then silicone them together as a stack. I'll feed it a rate to keep some water  trickling through the cans using a some sort of header pipe. At the bottom cans I'm thinking a piece of gutter with an inslulation top with holes drilled to accept the cans.  Box design would be a inslulated box covered with lexan or Tuff-R (trademarked) sheeting.  

At night I'll either quit pumping water through and allow drain back or I'll have a valve such the water ciculates to prevent freezing but not allow the chilled water to get to the storage tank.

Comments,thoughts?  Has anyone tried this before?

Cheers,

ajccmc

[spinningmagnets]

Several similar projects over at www.builditsolar.com. Each project with its particular strengths and weaknesses, pick one that suits you, and adapt to your exact conditions and cheapest materials available.

One of Gary's most talked about projects as far as effective and cheap is hot water solar trickle panels. Corrugated metal panels painted black under glass or poly carbonate. Water is stored in an insulated pit in the ground.

When the sun is out, a small PV panel powers a small DC water pump that pumps pit water to the top of the panels, and it trickles down. When there's no sun, panels are dry, so no freeze damage. Apparently works very well.

[GaryGary]

Hi,

Some specific designs that seem like they might do what you want:

The PEX/aluminum water heating collector:

http://www.builditsolar.com/Experimental/PEXCollector/PEXCollector.htm

You have to be careful about controlling stagnation temps on this one.

The Copper/aluminum water heating collector:

http://www.builditsolar.com/Experimental/CopperAlumCollector/CopperAlumCol.htm

The Modified Trickle Down Collector Richard and John:

http://www.builditsolar.com/Experimental/MTD/MTD.htm

This one has an inexpensive way to do a large storage tank and heat exchanger:

http://www.builditsolar.com/Experimental/PEXColDHW/Overview.htm

The pop can idea for a water heating is interesting.  I'd like to hear how it comes out if you go that way.  One little test I'd try first is to keep an empty aluminum can half submerged in hot water for a few days and see how it does.  In the past I've used bare aluminum tape exposed to hot water vapor, and it did not hold up well.  The pop cans have a finish on the inside, but I'm not sure how long it will last.

Gary

[ajccmc]

Any tips on sizing collector area to storage to sqft to be heated? I'm thinking now copper pipe and AL plates/fins per the article I was pointed to. Maybe use my cans to build air based one to "boost" things during the day.

ajccmc