soda can passive hot air panel, worth the hassle?

[CruisnGrrl]

We've been working on a popcan solar heater, we're using a combination of a design from rimstar and that has a star punched in the bottom of the can to create turbulence and another on builditsolar. how ever because we're on a budget and we already had them we're using plywood and 2x4's for the base/frame. Since there is no deposit on pop cans those truly are free as well. We sourced them from work and friends and family. Not really viable for a commercial operation.

We started punching a star into the top as well but that was more labour intensive than the star in the bottom, hard on the knife and probably redundant so I tried a can opener for the top and it worked well and was much quicker. Cutting the star in the bottom is still a little labour intensive and I'm not sure how viable it would be for a commercial operation, having a punch would be way easier.

It's still a work in progress and I will end up taking pictures eventually. We just finished "staring" the bottom of 240+ cans yesterday and are now cutting off the lids. pepsi and coke (and their brands) cans seam to be the easiest to work with. Store brand cans aren't as good and V8 cans seem to have reinforced lids as they were the hardest to cut open.

After I get the lids off the next step will be making the manifolds for the top and the bottom. we have some eavestrough/downspouts for that, then gluing the cans together and painting them black. We're lining the back with reflective bubble wrap and taping the sides. We still have to find a source for the polycarbonate that is reasonable in price.

To push the air we'll be using a solar panel and a small 12v fan so that the speed will adjust with the amount of heat that can be produced (I saw some one else had the same idea earlier in the thread).

[willythompson]

Hey just a heads up. I had came across this fellas claim to a manual for $4.95 before I found this forum, I figured well if he can point me to one thing I cant find on my own 5 bucks isn't a bad finders fee. So yes I was suckered in. I paypal d him the money, and never received the product, or the down load. several emails with no response. Who knows, maybe he is sick in a nursing home or something? Thru a quite tedious process Paypal decided in my favor and refunded me the money. 5 bucks wont kill anyone, but the principle of the thing irritated me. I hate being "had"

just a warning to anyone.. And Maybe a Mod could put this guy on notice, or at least warn others.

SolarHeater
SolarHeater is offline
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[dkdk3434]

Has the twin walled poly carbonate held up?

[rhawkman]

bcroe, yeah I used screen and suntuf, which I imagine is the same thing. I am not concerned with heat loss too much. It has insulation backing and I used 6" insulated ducts for the connection. Of course the real test will come when it gets cold this winter. My wood burner makes plenty of heat but I wanted to do this so in effect it was just another hobby and something I wanted to try.

[J.P.M.]

I could never see see why one of these heaters would perform better than just having a
window the same size on the side of the building. And there is all the heat loss of the
panel front & back. Maybe an advantage would be the ability to turn it off when the sun
isn't shining, or is too hot.

But now I'm thinking, maybe I could use the black screen and Tuftex 96-in x 26-in .32-
Gauge Clear Corrugated Polycarbonate to build one along the 45' length of an out
building. The back side of the heater would just be the present outside of the building,
so heat "loss" there would go into the building anyway. The objective would be to keep
the building above freezing all winter without running the furnace. Or even warmer if
possible; to work in there, I would use the current furnace to boost it to 65F.

Bruce Roe

Usually, comparing a window of any given orientation and an active solar thermal collector of just about any type, the window will produce more heat with less hassle and noise. As for overheating, that's why God made exterior shading devices. The window also serves other purposes such as providing a view and emergency egress. The advantage of active solar thermal collectors is they tend to be a bit more mobile and flexible in orientation, allowing for perhaps more output. per unit area.

[bcroe]

I didn't even try the pop cans because it looked like a ton of tedious
work cutting them all and putting together. That's why I went with the screen. Far easier and the
tests on builditsolar said it (the screen) worked best. I applaud your hard work

I could never see see why one of these heaters would perform better than just having a
window the same size on the side of the building. And there is all the heat loss of the
panel front & back. Maybe an advantage would be the ability to turn it off when the sun
isn't shining, or is too hot.

But now I'm thinking, maybe I could use the black screen and Tuftex 96-in x 26-in .32-
Gauge Clear Corrugated Polycarbonate to build one along the 45' length of an out
building. The back side of the heater would just be the present outside of the building,
so heat "loss" there would go into the building anyway. The objective would be to keep
the building above freezing all winter without running the furnace. Or even warmer if
possible; to work in there, I would use the current furnace to boost it to 65F.

Bruce Roe

[rhawkman]

I didn't even try the pop cans because it looked like a ton of tedious work cutting them all and putting together. That's why I went with the screen. Far easier and the tests on builditsolar said it (the screen) worked best. I applaud your hard work

[russ]

I built a pop can solar heater a couple of years ago. Here is a website showing it done: https://sites.google.com/site/brianshomebrewsolar/

It will fun and not too expensive, but I will say it was labor intensive and I believe you would get more heat and less hassle from a black screen type collector.

The pop can collector was tough to get all the cans bonded together and the manifold was sketchy...(at least mine... )

Brian

Well done Brian - looks good!

Russ

[Grizzly Brian]

Pop Can Solar Heaters...are they worth it?

I built a pop can solar heater a couple of years ago. Here is a website showing it done: https://sites.google.com/site/brianshomebrewsolar/

It will fun and not too expensive, but I will say it was labor intensive and I believe you would get more heat and less hassle from a black screen type collector.

The pop can collector was tough to get all the cans bonded together and the manifold was sketchy...(at least mine... )

Brian

[rhawkman]

I bought 4 cooler master 120mm ball bearing silent computer fans for just over $15 from amazon. Claim 44CFM. I considered yanking one out of an old computer but wanted quiet. I may still try that just to see since that desktop is just holding down the carpet in a closet. If I could get a 28v fan from my old work that were used in aircraft boxes that might be an idea. If the picture uploads you can see the PV should get light and start moving air before it gets too warm and run a bit after the collector stops making heat.

[bcroe]

After all my research and pondering (and procrastinating) I finished my solar screen heater that I found the plans for on builditsolar.com Finally have my solar screen heater hooked up. Don't really need it today as it is about 60F outside, but this is the temporary hook up of the fan and ducts going into living room window. 70F air at lower inlet and the fun pushing ~150F air out the top duct running a 12v boxer fan with a 5w solar panel. It might be a simple project and not the prettiest thing in the world but I am feeling pretty good about it working as planned. A higher CFM fan would help but hard to find 12v fans that run on less than .5A and are silent. The fan is hooked up directly to the solar panel with no battery so the fan will only run when there is enough sun to make heat anyway.

150F, very nice. The fan automatically runs when it needs to, an elegant design. Most fans are
far quieter when run around half voltage; maybe a bigger 24V fan would be ideal. Bruce Roe

[J.P.M.]

After all my research and pondering (and procrastinating) I finished my solar screen heater that I found the plans for on builditsolar.com Finally have my solar screen heater hooked up. Don't really need it today as it is about 60F outside, but this is the temporary hook up of the fan and ducts going into living room window. 70F air at lower inlet and the fun pushing ~150F air out the top duct running a 12v boxer fan with a 5w solar panel. It might be a simple project and not the prettiest thing in the world but I am feeling pretty good about it working as planned. A higher CFM fan would help but hard to find 12v fans that run on less than .5A and are silent. The fan is hooked up directly to the solar panel with no battery so the fan will only run when there is enough sun to make heat anyway. I tried to upload pics but it says they are too big. Like I said, nothing fancy, just function.

Congrads. The feeling I got from what sounds like a very similar experience many years ago is still vivid in my mind. Nicely done.

[rhawkman]

Built mine

After all my research and pondering (and procrastinating) I finished my solar screen heater that I found the plans for on builditsolar.com Finally have my solar screen heater hooked up. Don't really need it today as it is about 60F outside, but this is the temporary hook up of the fan and ducts going into living room window. 70F air at lower inlet and the fun pushing ~150F air out the top duct running a 12v boxer fan with a 5w solar panel. It might be a simple project and not the prettiest thing in the world but I am feeling pretty good about it working as planned. A higher CFM fan would help but hard to find 12v fans that run on less than .5A and are silent. The fan is hooked up directly to the solar panel with no battery so the fan will only run when there is enough sun to make heat anyway. I tried to upload pics but it says they are too big. Like I said, nothing fancy, just function.

[russ]

Hi psychowolf - Welcome to Solar Panel Talk!

Russ

[psychowolf]

Thank you for the info.

I live in Armenia and we have cold winters here and the idea of insulating homes has not been employed yet. I am in the process of trying to get enough cans to build a panel now. The biggest problem is that there are many more glass bottles used here for drinks than cans. So it is taking me a while to collect them... But thanks everyone for all the tips and information.