Viewing post #2439448 by pyrapod

BruceM2 said:Soap bubble insulation has been proven, but when done side to side with reflective insulating curtains, it was not substantially better. Which tells me that the end wall and earth losses are a bigger portion of the total thermal loss than i would have expected. So it's a lot like building a super-insulated home; you must address ALL the losses.

[url=file:///C:/Users/Bruce/AppData/Local/Temp/69-1644-15-03_Final_Report_Use_of_Soap_Bubble_Insulation_in_Greenhouses.pdf]file:///C:/Users/Bruce/AppData...[/url]

So I do think soap bubble insulation could be a good way to eliminate the mechanical and electro-mechanical issues of moveable insulating panels. Soap bubble systems do introduce their own maintenance and reliability issues.

In my own testing, I found that I was able to easily produce an 8 foot column of fine bubbles rising from a 5 gallon bucket by feeding compressed air to a coil of recycled rubber weep hose in the bottom of the bucket, with the bucket half filled with bubble solution (water, detergent). This eliminates the requirement for overhead active plumbing and blowers, and since it's simpler and better contained, even toxic glycol antifreeze could be used in the bubble mix. An insulated trough lined with pond liner would hold the solution.

For my test, I was using about 35 psi from my shop air compressor but I'm sure lower pressure could be used (such as a shop vac or leaf blower motor) with the right perforated air emitter.

One of the annoying things about soap bubble insulation is that a great deal of thickness is required, and the degradation of plastic/film over time from the solution and UV breakdown of the solution residue. The R value is estimated by different sources between 0.5 to 1 per inch. The original Canadian greenhouse application used 30 inch spacing.

I'd love to see a commercially available, well designed home/hobby greenhouse with a soap bubble insulation system!

Bruce, thank you for sharing your experience.

Looks like you are using the same method those aircrete guys are using to produce bubble foam. By the way, that is the slow way and OK for aircrete mixing, but not fast enough to fill large cavity for greenhouses.

To produce bubbles the faster way is to use a fan, a nozzle and a large screen covering. Go to our website and check the video section. You will see several videos showing how massive amount of bubbles can be produced easily.

We have finished designed a full line of commericial products and now in the process of testing for the next step: mass product.

Fortunately the inventor is still relatively young and can help us personally. He has been doing this for 40 years and he knows all about it including little secrets that no one will get it right even if they can replicate some aspects of the technology.