How to Build a DIY Solar Air Heater From Old Soda Cans

https://www.treehugger.com/ ^ | October 11, 2018 | Sami Grover

[T.B. Yoits]

The designs I’ve seen have one long coil to really build up the heat instead of parallel tubes like pictured with the soda cans.

[logi_cal869]

Not trying to be an ass (I was headed to the rack and not feeling well last night). I took a few minutes this morning to find reference to what I was describing last night.

The acreage is moot. Such panels must be attached directly to the structure as energy is lost in transfer.

My point is that there are 2 principal types of such solar collectors and the ‘curtain’ type (vs. ‘can’) is cheaper, more compact, incredibly more aesthetic, permits greater airflow and facilitates thermal transfer efficiency (for obvious reasons).

This guy saved me the time/expense/frustration of making mockups for testing (I’d have done exactly what he did):

https://www.youtube.com/watch?v=PyVPNOUpOVg

In comparison, the ‘downspout’ collector is perhaps a viable alternative, but I’m dubious that it’s worth the extra materials & bulky collector (certainly better than the cans on every level). The bottom video outlines the fabrication, which can be used for either type.

https://www.youtube.com/watch?v=SniCLlTIIAs&t=2s

https://www.youtube.com/watch?v=XwUT0ytPfLA

Ignore the temperature differences between the different videos. There is no way to ascertain location in any of the videos so comparison can only be made per collector in the same video.

And, btw, when I reference expense, I’m in the NW, so higher quality materials are on my list to survive the wet climate. At my latitude, I should easily see a return on my investment in the winter. Had other projects not gotten in the way, I’d have pics of the completed panels (seasonably removable) attached to the house.

The prodigious research for my specific needs outline compact collectors attached directly to the outside of the south side of the structure, lightweight to both minimize mounting concerns and facilitate being removable, the latter of which minimizes expense. In my single-story structure the intake vents will be vertical (another aesthetic design concern), directly into the soffits and directed via short, insulated ducting directly to ceiling vents in the interior (and easily blocked off seasonally when the collectors are in storage on the north side of my utility shed). Solar fans are an option, but I believe that convection from intakes connected to my subfloor ducts will suffice without the added expense & complexity.

[Vaduz]

On the plus side it has no mercury in it like the reals ones do.

[The Great RJ]

This scheme was popular back in Jimmy Carter’s day and it was not uncommon to see these hillbilly heaters on homes. However, most were discarded as they never lived up to their promise of free heat

[Newbomb Turk]

That makes sense to me !