Welcome to the Solar Collector
Brainstorming and Development Page!


 

Home

Hot Air Collector

Hot Water Project 1

Hot Water & Space Heating

Solar Electric

Solar Construction 101

FAQs

Best Collectors

Simply Solar
Sign up Latest Topics
 
 
 


Reply
  Author   Comment  
stmbtwle

Avatar / Picture

Registered:
Posts: 3,063
Reply with quote  #1 
To give credit where it's due, Gaiatechnician put me on to this. Suppose landscape fabric were used as the back screen in a zero-pass, or as a single-layer absorber with air flowing on both sides of it?

Durability might be an issue.

__________________
Solar is like the wind. It may be free, but putting it to work isn't!
Willie, Tampa Bay

SolarInterested

Avatar / Picture

Moderator
Registered:
Posts: 1,109
Reply with quote  #2 
SolarDan tried it with poor results as far as surviving stagnation

http://simplysolar.supporttopics.com/post/show_single_post?pid=1279944790&postcount=46

__________________
Both temperature rise and airflow are integral to comparing hot air collectors
KevinH

Registered:
Posts: 565
Reply with quote  #3 
There have been various discussions about the materials that could be used including landscape fabric and their pros and cons.  Do a Search for "landscape" or "fabric" to find them.  I would recommend doing testing before committing to a new material to see how it handles heat and if it gives off odor.  Greenhouse shade material that comes in different shading levels has also been mentioned.

Kevin H
MN
solardan1959

Avatar / Picture

Registered:
Posts: 1,845
Reply with quote  #4 
Good advise, wish I would have thought of that before I used it. (and this was the better stuff)

[image] 
Dan
gbwillson

Avatar / Picture

Super Moderator
Registered:
Posts: 2,461
Reply with quote  #5 
Dan-

The melted material in your photo looks more like plastic film. While on the right side of your image it looks more like a woven texture. Are they the same material?

Greg in MN[wave]
solardan1959

Avatar / Picture

Registered:
Posts: 1,845
Reply with quote  #6 
Greg,
  Yes, high end landscape fabric from Home Depot with a 20ish tear guaranty.  Somewhere after this happened I did some heat gun test with a more fabric like woven version and it did much worse.
Found it under page #5 of my pole barn heater stuff  http://simplysolar.supporttopics.com/post/pole-barn-heater-test-bed-6277354?trail=50

[image]

 They "good stuff" from above actually held up better, the stuff on the right acted like I took a flame thrower to it and would just vaporize.  I just swept the heat gun at the same speed and when it got to the fabric stuff, "poof"  The stuff on the left did seem more rubbery.

Dan
gbwillson

Avatar / Picture

Super Moderator
Registered:
Posts: 2,461
Reply with quote  #7 
Whenever I see something melted, I can first think of the wicked witch in The Wizard of OZ.
I think any synthetic fabric you are thinking of using as a collector should be verified with the manufacturer. I doubt most landscape or screen fabrics will list what they are made of. As someone mentioned, you could test a small piece in the oven, look up the MSDS or call the manufacturer before purchase.

Greg 
stmbtwle

Avatar / Picture

Registered:
Posts: 3,063
Reply with quote  #8 
Well that pretty well takes care of that idea, for sure! 
__________________
Solar is like the wind. It may be free, but putting it to work isn't!
Willie, Tampa Bay
solardan1959

Avatar / Picture

Registered:
Posts: 1,845
Reply with quote  #9 
stmbtwle,
  It has issues for sure, Charlie Gorky from Kentucky sang it's praises claiming it put out a higher temp than his later screen versions.  The important thing is he made the screen versions because his higher output collectors disintegrated after a year or two, probably because it lacked UV protection.
  But because of his claims and the low price I used it several times.  The first time was on my shed heater when I redesigned it.
[image]

  I used a layer of the fabric first then a layer of screen over it.  This is a mainly thermo syphon unit so it never gets real hot as the hotter air just flows out of it.  I have never had any issues with it used like this.

  The second time was my poor design that requires good flow to make work because the air was flowing up and down not back and forth.  With the up and down the hot air would rise and not flow and the above photos show the result.
 
  I probably will not use it again and would rather used solar screen or greenhouse shade cloth, but with proper design it is cheap and could be used.  Kind of like cpvc,  I have melted, well deformed, all I have used by letting it get too hot one way or another.  many people have used it for years and never had an issue.

  Dan
Previous Topic | Next Topic
Print
Reply

Quick Navigation:

Easily create a Forum Website with Website Toolbox.

 

web statistics