A company called "Watercone" came up with an old idea and turned it into a commercial product: a simple plastic cone that you put over a body of water, after which the water evaporates through the solar energy, and so it becomes drinkable. The problem: the watercone costs US$ 150. Which is obviously way too much for the people for who it was intended (people in developing countries). US$ 150 is more than the average Congolese earns in a year.

I'm pretty certain that my alternative will be cheaper. Instead of making the cone of hightech "makrolon" injection molded plastic, just make it of low-cost plastic and make it inflatable. The original cone is made from makrolon because the device must be rigid. They simply didn't think of the fact that inflatable thingies can be rigid too.

I know this idea borders on the banal, but it could be an elegant way of reducing the cost of the watercone, which in itsself is a fine technology.
-- django, Apr 10 2006

Watercone http://www.watercone.com/product.html
The original injection molded makrolon cone, costs US$ 150 [django, Apr 10 2006]

Complex inflatable structure http://www.shop.com...937125?sourceid=298
Costs US$ 8.95 [django, Apr 10 2006]

Nasa inflatable http://www.grc.nasa.../inflatable_srs.jpg
inflatable solar stirling dish for deep space [django, Apr 10 2006]

Inflatable tent http://www.gonowspo...ld_nofly_detail.jpg
Use simple ribs to keep the structure up, instead of entire inflatable walls. [django, Apr 10 2006]

Inflatable Solar Stills http://store.yahoo....dfallnav/memss.html
...are nothing new - they were widely used in the Second World War. But they don't seem to be especially cheap. [DrCurry, Apr 10 2006]

corrected link to inflatable tent poles http://www.airzonetents.com/airzone4.htm
DJango's link (two above) doesn't work anymore.... Use simple ribs to keep the structure up, instead of entire inflatable walls. [pashute, Jun 03 2008]

Vango airbeam tents - corrected correction 2013 https://www.vango.c...-airbeam-tents.html
[pashute, Aug 28 2013]

Sea water solar distiller Similar but more "active" idea [pashute, Aug 28 2013]

Is this different enough to survive a patent challenge? I have no Idea. I like the idea of both the Watercone & the idea to make it more affordable.
-- Zimmy, Apr 10 2006


I think the advantage of the inflatable cone is that it could be quite big, and remain portable when deflated.
The disadvantage would be the inability to repair punctures. I see the instruction manual includes advice such as 'don't keep animals under the cone'. With this type of user in mind, the simplest and strongest device might be the best option.
-- Ling, Apr 10 2006


Sounds good, but then you're having the greenhouse effect within your walls instead of the chamber with the water.

(Inflatable walls would absorb the solar energy and heat up the trapped air in the walls, and leave less solar energy to heat up the water.)

And, hotter walls would mean less condensation on those walls.

But, it should be pretty cheap/easy to build a prototype & try it out, & prove it one way or another.
-- sophocles, Apr 10 2006


//Sounds good, but then you're having the greenhouse effect within your walls instead of the chamber with the water.// I was more thinking of a cone with two simple inflatable ribs. (A bit like the inflatable tent [see link]).
-- django, Apr 10 2006


What bigsleep said: I'm thinking mass production of that design would cost much less than $150 a pop.

Making it inflatable wouldn't add any significant savings over that, and would introduce failure points not present in the simple original design.
-- DrCurry, Apr 10 2006


Hmm... OK. "ribs". Makes sense. Still, rigid transparent plastic isn't very expensive. C'mon, soda bottles? $150?
-- sophocles, Apr 10 2006


With a little paint and some additional design modifications, the inflatable cone could double as a hooker, earning its keep while supplying you with valuable water! Bonus!
-- luxlucet, Apr 11 2006


Mm, I think the process of blow molding, rotomoulding or injection moulding is what drives up the cost. Production of an inflatable uses much less plastic and it uses a simple 'glueing' process. So I'm pretty sure that this makes a difference.

Also, in order to make a rigid cone, you need a lot more material (I'm no expert, but I think you need at least ten times as much plastic).

Anyway, there must be a reason as to why the massproduced watercone still costs US$150.

A company that presents itsself to solving a world problem, involving the poorest people on the planet, cannot be taken seriously if it talks about a product with such a ridiculously high price. So either the people running that company are completely out of their minds, or else, there must be a technical reason for the high price.
-- django, Apr 11 2006


[django] You're assuming too much. Looks like the watercone company is not really off the ground yet, and doesn't sell direct to individuals. It's $150 US for 1 liter per day. You'd need between 4 to 8 of these to provide enough water for one human being to survive off of (just for drinking alone).

So, who's going to spend $600-$1200 PER PERSON to provide drinking water? I'd think you could run desalination at large scales, build pipes, etc, and get it to be much less per person for larger volumes to supply agriculture, not just drinking.

My point about soda bottles is that rigid "enough" plastic is still very very cheap.
-- sophocles, Apr 12 2006


Umm - cheapest way to do this is with a teepee made from plastic sheet, and more sheet to make the annular collector at the bottom. I suppose a little plastic welding might come in handy to make a V shaped pocket that goes around the inside of the sheet as the water collector.
-- dmorton, Oct 06 2009


/don't keep animals under the cone/

I am thinking of Dune style water reclamation from animals. I think they used dead animals and people. Certainly after you have reclaimed a percentage of the water that would be the case.
-- bungston, Aug 28 2013



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