soda can passive hot air panel, worth the hassle?

[green]

I design my own stuff. It's just how I am. I borrow the best I can find and make it my own. I actually have a design for a solar heater(not one of these big ones) I might want to patent. I need to see how it preforms this winter. I can't say to much about it because I haven't seen anything like it but there is one guy that is getting close.

[SolarHeater]

Time and materials cost

I of course love to get things for free and borrow ideas. When one spends money and time in designing something of value to others such as I have, I don't think "suckering" anyone into buying my manual is a fair assumption. In fact, the odds of me recouping the costs for building several test units on top of the cost I paid for editing is very likely. Asking $4.95 for a book I've written is certainly acceptable and the Million books now on Amazon can support this fact that authors are deserving of payment for their work. I paid $30 for a manual showing me how to assemble solar panels for example. I'm glad to have paid the author for his time and expertise.

A manual such as mine goes farther than a video in that it lists all the parts needed and gives a step by step process for assembly, both of which save time. And time is money for most people. I'm happy to hear your opinion, and this is mine. Have a happy day guys.

[russ]

I of course love to get things for free and borrow ideas.

If you wish to advertise your ''commercial venture'' contact the site sponsor.

[SolarHeater]

That is not a problem, Russ.

If you wish to advertise your ''commercial venture'' contact the site sponsor.

[SolarHeater]

Patented Solar Heater

Hi Green, Yes there's Solar Air Systems, if that's who you refer to. They have a patent on the "Stepwise" technology as well as their heat plenum tubes. Theirs is the fan controller I have referred to.

I design my own stuff. It's just how I am. I borrow the best I can find and make it my own. I actually have a design for a solar heater(not one of these big ones) I might want to patent. I need to see how it preforms this winter. I can't say to much about it because I haven't seen anything like it but there is one guy that is getting close.

[green]

Hi Green, Yes there's Solar Air Systems, if that's who you refer to. They have a patent on the "Stepwise" technology as well as their heat plenum tubes. Theirs is the fan controller I have referred to.

That's not who I'm refering to. I do like their stuff though. I'm actually repurposing an engineer's idea I saw. I can't say how because that is the major patentable difference here. I really can't believe noone thought of this before. I don't have a large scale facilty in which I can test this under winter like conditions. It's been 90F outside here every day since I got this idea and made a prototype.lol. If my theory is correct, it could mean huge energy savings for a small unit and small $$$.

I can't wait to share it. But first I must test, document everything, and talk to a patent lawyer. This time I need to do it right. I had an idea 15 years ago called the solar powered attic vent. I talked to Broan before I had a patent. Not one of my smarter moves.

[SolarHeater]

Sounds very interesting. Yes, get a patent. I have a product patent pending and it's surely not an easy or cheap process. Do your homework on affordable and reputable attorneys. And then it comes time to market to a manufacturer. Keep us posted. I'd be very interested in seeing it someday. I would be happy to sign a non disclosure if you should ever need assistance.

[martinmarion999]

Don't get suckered in to paying for a design - they are available for free on the net.

Polycarbonate has reasonably good light transmission characteristics and some formulations are UV resistant - the mfg tells you this.

Thanks

[a10fjet]

just use a can opener

I saw a few people saying they were using drills or knives and a grinder to open the cans.
All you need is a can opener for the top and a drill for the bottom. The can opener cuts the top off perfectly, no sharp edge at all. They stack super easy and you save loads of time

[green]

I saw a few people saying they were using drills or knives and a grinder to open the cans.
All you need is a can opener for the top and a drill for the bottom. The can opener cuts the top off perfectly, no sharp edge at all. They stack super easy and you save loads of time

Yes but you want some turbulence of the air and removeing the bottom cuts down on turbulence. I'm currently experimenting with different techniques and will report my findings when I've tried a few. A sharp punch and a hammer is my fave so far.

Green

[russ]

Yes but you want some turbulence of the air and removeing the bottom cuts down on turbulence. I'm currently experimenting with different techniques and will report my findings when I've tried a few. A sharp punch and a hammer is my fave so far.

Green

Pressure drop is far more important - getting a bit of turbulence should be no big deal

[mocars2]

My solution to glass was a super light weight dual-walled 4'x8' polycarbonate panel readily available for just $39. It's surprisingly inexpensive at less than half the price of a 3'x7' piece of plexiglass that's $99 at the same store.

I'd love to know where you can get a 4' x 8' polycarbonate panel for $39.
Menards has a

Clear Colorless Polycarbonate Plastic Sheet 0.220" x 48"W x 96"L
For $354
They also have a small piece for $21 -

.093" 18" x 24" Clear Polycarbonate

So let us know where to fine one that size for that money.thanks

[likes to eperiment]

Cans are an old idea, try this!

Ok, So i'm kinda new here, but not new to solar tinkering. I've been reading about cutting hole in cans, air turbulence, heat transfer, and the cost of such items, and amount of labor involved. I submit that i have solved all of these issues and done so cheaply, effectively and at a minimum of labor!
Instead of thinking of can tubes, gutters, aluminium coil, think of metal window screening, steel plaster mesh, and spun furnace filter material!!!
I swear they all work unbelievable, the furnace filter media is easiest of all as you can get the charcoal black version that works almost too well! high temps!!! The Metal window screen in black is the most expensive but it can be found very reasonable on seasonal sales. The plaster steel mesh needs to be spray painted black but is cheap and works well too!
There's no issue with adding turbulence as its built into the material to start with.
As for a on/off thermal fan controller you will love this, i simply wire in a thermostat for a roof fan into the fan circuit they are cheap and come with variable settings.
I was able to bet 5100 BTU's from a 4ft x7ft collector.
In really simple terms: this is what my HVAC buddy measured with the expensive meter. (i just used a remote grilling thermometer) but his was able to estimate the BTU value, taking relative humidity, CFMs, Temp. factors.
air went in at 43*
air came out at 112*
at a rated 110cfm computer fan pushing air in (not sure what the actual FPM outflow was cant remember but it was pretty generous)
My HVAC buddy was just amazed, simple, cheap, effective. I used 8mil. window film, and foiled bubble wrap behind collection media to reflect back into any radiation that made it through first pass.
The heater has been disassembled because i want to make a beefed up weather hardier version this season. You guys need to try this out it really quite a new and novel idea that solves lost of the issues we used to wrestle with.
Have fun, be safe, don't burn anything up or down, and keep experimenting.... Michael

[green]

Wow, thanks for the ideas!!! I've been thinking outside the box(literaly) on solar thermal for a while now. I have a few more test units together that I am gathering data on as we speak. I'll be posting pics and results in the weeks to come.

Green

[gizmo2337]

Have you read Gary's or Scott's comparison of DIY solar air collectors? I found it to be very interesting. The soda can build should be similar to the downspout type in construction, just using free aluminum (well you pay a deposit on a can, so maybe not free).

http://www.builditsolar.com/Experimental/AirColTesting/Index.htm

http://www.n3fjp.com/solar/index.htm

Based on testing, the 2 or 3 screen absorber is the cheapest and simpler build and has a low pressure drop. I don't see any mention of this in this thread, so I thought it was worth mentioning. I started out looking at the soda can design, but I think I will do the screen design. With a little planning, that design could be done in an afternoon instead of a couple weekends. I suppose you could use polycarbonate sheet, but it is expensive around here. 26"x8' Palruf clear roofing sheets are only $18 at home depot. I might even change the box size to match the sheeting so you don't have to join two sheets and add extra support.

I am interested on materials to use other than wood that might be cheap and lightweight if anyone has any ideas, that would be awesome. Also, a lightweight weather proof backing would be needed. I am still ironing out the details to "ruggedize" the panel without adding huge weight.