The last time I saw a post about one of these, it was mounted vertically and so the heat just came out the top through a vent into the building (cold air went into the bottom from the building too, but you probably assumed that!)  

I'm guessing then that yours is fed by forced air, from a blower or fan?

I push the air thru with a 250 CFM squirrel cage fan controlled by a snap disk thermostatic switch.

I need  more air flow. The fan does not cut out from the time the sun hits the panel. (The panel makes heat faster then I can pull it out.) Even with an outside air temperature below 30C I still get +80C out.

When I get some time I'm planning on converting some of this hot air into hot water.

another throw away material you can use is old
burnt out fluorescent tubes.

Using a stainless steel wire and a 12v car battery you
can cut the ends of the fluorescent tubs off.

I guess this is built by vertically stacking the cans with some size hole drilled (hole saw?) in the bottom of each can in the stack?  I suppose with your soda/pop cans you need to line up the drinking hole in the top with hole you drill in the bottom of each can beneath?  

Do you seal or tape the cans together, or glue (caulk / silicone) them to the back?  I see you have stacked them and built this on a nominal 4 x 8 foot foam board sheet.  Looks good.  Do folks ever stack these type arrays together (series, as it were), or just draw the air off in parallel if they are using more than one?

I think the steel cans would rust from any mositure in the air. At night the cans would get cold and the warm moist air inside would condense and I'm sure there would be some corrosion.

I do notice the first bit of air out of it on start up appears humid.  It dries out real fast.

High temp silicon the cans together.  I used a piece of angle iron to make a little jig. Elevated one end and let them set up. Keeps them nice and straight. then I silicon the cans onto the insulation. Then painted. Make sure to use an insulation that is UV rated so it does not break down.   The R-Max has an aluminum foil which solves this. The cut ends need to be protected. Some planning in your cuts and overlaps solves this problem. Seal the seams with silicon.  My box is airtight. Try to seal it all up on a low humidity day. (No moisture inside to condense on the lens.)

As for the holes in the end, I don't recommend a hole saw. It grabs the thin material too fast and the can becomes a dangerous spinning weapon.  Try a wood bit in your drill press. Go slow and careful. The point of the bit scrapes thru the aluminum nice and clean. My bit did 240 cans and doesn't appear worn at all.

I don't see a need to run these in series.  The air out is very hot.

Ok, I think I got all your questions.  If I missed something feel free to ask.

Sorry I drifted off topic on my previous comment.

I like that idea and it looks like a good project. A small PV panel driving a fan would make it stand alone solar powered. I use a little makeshift unit like that in my office window. A PC fan a small 12 volt PV panel and an aluminum dryer vent flex tube painted black. Works pretty well for its size.

Cheers.

TomW

The Truth is the Truth, even if no one believes it; and a lie is a lie even if everyone believes it

Hope you have time to answer a few questions.

Any difference in your heating bill?

How many sq feet is it heating?

Do you have any plans that you can post?

What did you build your frame out of?  Is that white paint or some type of covering on the frame?  What did you use for the back of the frame?  What about fire hazard?

I notice that your covering is not flat are your cans also in an arch to match your cover?  Does it mater if it is flat or arched?

What did you make what appears to be a manifold out of?

Are each column of cans connected so that air enters in can #1 and works its way out at can #240 or does air enter each column at the bottom and exit at the top of the column?

What about toxic off-gassing from the glue, paint or other materials in the construction?

What do you do with the unit in the spring, summer months?

I've been playing with different fin designs on the bottom of the cans. I think cutting fins in the can bottoms will act as a heatsink, allowing the air to soak heat from the can. We know the sun heats the cans up and the most efficient designs should keep the heat collectors (cans) cool. This means that as much of the suns heat as possible is being absorbed by the air...

If your output air temp is well over 80 degrees then maybe you need more airflow?

Thank You