
Scientist Creates Self-Filling Water Bottle - Vilvaram1
http://thenextweb.com/shareables/2012/11/21/inspired-by-a-beetle-that-draws-water-from-the-air-scientist-creates-self-filling-water-bottle/
======
eykanal
> Sorenson notes there is more than three quadrillion gallons of water in the
> air, which is essentially a massive untapped resource.

For what it's worth, air with low humidity can be pretty damaging. Lots of
materials would become excessively brittle at very low humidities, causing
them to break easily. This interesting white paper [1] suggests that, for most
materials, the optimal humidity is between 40-60%.

Still, this is a very cool concept.

[1]
[http://www.descoenergy.com/pdf/Humidity%20How%20it%20affects...](http://www.descoenergy.com/pdf/Humidity%20How%20it%20affects%20Materials.pdf)

~~~
james4k
This might be true, but the atmosphere is also very good at reabsorbing water.
Especially if humidity levels would be lower than normal.

~~~
mylittlepony
I thought that would happen, it's kind of intuitive.

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Someone
Background info: <http://en.wikipedia.org/wiki/Air_well_(condenser)>

The device in India shown there produces 15 liters of water per square meter
per year. The surface area of a bottle is, say, 500 square cm, or 1/20 of a
square meter. That would produce about a liter in a year.

[http://www.iimahd.ernet.in/publications/data/2005-01-05gshar...](http://www.iimahd.ernet.in/publications/data/2005-01-05gsharan.pdf)
talks of 0.042 liter per square meter per day, in extreme.y high humidity.

Clearly, some efficiency gains are needed w.r.t. those designs to effectively
make the claim "water bottle tha fills itself". Whether that is possible, I
don't know.

~~~
novaleaf
if you read further down in the wikipedia article, it shows zibold's collector
which produced about 0.9 liters/square-meter/day

just pointing out that efficiency may be better than what you are estimating.

~~~
Someone
It may be, yes, but Wikipedia isn't convinced. Even further down, it states:

 _"Zibold's condenser had apparently performed reasonably well, but in fact
his exact results are not at all clear, and it is possible that the collector
was intercepting fog, which added significantly to the yield.[10] If Zibold's
condenser worked at all, this was probably due to fact that a few stones near
the surface of the mound were able to lose heat at night while being thermally
isolated from the ground; however, it could never have produced the yield that
Zibold envisaged"_

That made me look for more recent data. That PDF from 2005 was the best I
could find.

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ChuckMcM
Hmm air can carry a few grams of water per kG of air [1] and 1kG of water is
one liter, so if you can pull 1g of water out of each kG of air you need 1,000
kG of air. Stole this from wikianswers: "Each mole has a volume of 22.4 liters
and a mass of 28.97g/mol at STP, therefore a cubic meter of air is 1.293 kg at
0o Celsius on the coast. An average mass of 1.2kg per m3 at room temperature
and standard pressure is often used as a rule of thumb." so that would suggest
about a thousand cubic meters of air flowing past this bottle's extractor area
to get one liter of water out of the air.

No idea how long that would take though.

[1] <http://en.wikipedia.org/wiki/File:Relative_Humidity.png>

~~~
Jabbles
Good work. I imagine 1g/1m^3 is roughly what you'd expect - especially in a
desert.

If the extractor area is the size of the bottle's cap (2cm x 2cm = 4e-4m^2)
then to get a litre of water (1e3 m^3 air) requires 2.5e6m of air to flow past
it - If you want it full in a day that's 30m/s... hmmm... doesn't seem likely.

However if the size of the extractor area is as large as the bottle (say 10cm
x 10cm = 1e-2m^2) then a 1 m/s wind may do it.

Based on this I'm not confident in the "marathon runner" claim, but I'm sure
techniques for extracting water from wind have been used before, but
improvements could be made.

Scaling up the technology obviously increases the viability, yielding
something like this: [http://www.geek.com/articles/geek-cetera/prototype-wind-
turb...](http://www.geek.com/articles/geek-cetera/prototype-wind-turbine-
condenses-1000-liters-of-water-a-day-from-desert-air-20120418/)

~~~
andrewcooke
i think you're confusing collecting area with airflow cross-section. they're
completely different things, unless somehow the air is blowing _through_ the
side of the (solid) bottle.

~~~
Jabbles
Not really. This volume of air has to make contact with the bottle, whatever
the collecting area's shape. Imagine loosely fitting a tube around the neck of
the collecting area. All the air has to pass through that tube.

~~~
andrewcooke
no, i'm saying that only a small fraction of the incident air will touch the
surface. most will flow around - probably laminar flow containing a stagnant
area of higher pressure directly in front of the obstacle.

you are calculating the swept volume. but only a small fraction of the swept
volume "makes contact" (ie is roughly within the mean free path of a water
molecule) with the collecting surface (which appears to be necessary here for
water to be extracted).

with netting your argument is closer to being correct. but this is an
impervious bottle, not a net.

if you implemented the tube you suggest (and i understand that was simply an
illustration to explain swept volume) then pressure would increase in the tube
slowing flow and/or flow would be predominantly around the edges, with, again,
a stagnant higher pressure region in the centre.

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nickbarone
My question is what kind of contaminants (or none!) this process picks up - If
you're getting your water from a polluted atmosphere (say, LA), what kind of
pollutants end up in your water? Or does it produce "ultra-pure" water,
leading to weird health risks like hyponatremia?

~~~
ars
You won't get hyponatremia from overly "pure" or distilled water. The amount
is water is utterly dwarfed by the amount in food.

If there are pollutants in air they will be in the water, but it's not a
actually a problem because, although they might be bad to breath, most air
pollutants are harmless when eaten.

Carbon (soot), Ozone, NOs, sulfur dioxide (smog), etc are harmless to eat.

~~~
nickbarone
Interesting. Are there any that are the other way around - dangerous when
eaten, but not when inhaled?

I'd imagine it'd have to do with the digestive ecosystem, if there were any
that worked that way.

~~~
ars
I don't know of any.

But if there were it would be something that requires acid or digestion to
"activate". Or perhaps something that can't be absorbed without something the
only exists in the gut.

Bacteria actually could do that. Inhaled they would rapidly die, but in the
gut they could live (more food for them) and cause illness.

Also, the gut will absorb things faster than the lungs. So I could easily
imagine a toxin that has little effect when inhaled (since it's absorbed too
slow to cause damage) but causes trouble when eaten (everything is absorbed at
once).

But I don't know of any specifically.

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adriand
This may be a stupid question, but if the device requires power in order to
move air over the water-collecting surface, would it work without power if it
were outside in a breeze? Or is there something about the air flow in terms of
its characteristics or location in/on the device that requires a manufactured
flow?

~~~
hcarvalhoalves
I guess the airflow is to make it more efficient. In high humidities, you can
easily collect 1 liter potable water with a 3m2 plastic sheet, a clean
recipient, a hole in the ground and some sunlight, or just hot weather. It's
an old survival trick. His apparatus is a kind of upgrade.

~~~
SiVal
The plastic sheet process is different from the one in the article. In the
case of the plastic sheet, you are baking the water out of the ground, not
extracting it from ambient air. It seldom works well in practice, because you
get a little condensation under the sheet, but it's not enough to run in
rivulets into the jar, and when you DO get a few drops in the jar, the same
process that is baking the water out of the dirt evaporates it from the jar.
You end up shaking the plastic, lifting it up and licking it.... Works better
in theory than in practice.

But imagine that, instead of a special water bottle, you have a poncho-sized
sheet of coated plastic in the shape of a windsock with a coiled wire ring at
the opening and a pouch at the end. If this could work like the beetle's wings
and take water out of the ambient air, that would be interesting.

~~~
harold
I spent some time learning from a respected survival expert who claimed the
'solar still' was not an efficient use of one's energy. I tried it out a
couple of times anyway and proved to myself that he was right.

What did work fairly well was a transpiration bag [1]. It took a few bags to
get a meaningful supply of water and one needs to be careful about the foliage
used.

[1] <http://www.youtube.com/watch?v=q2EBiA0Csts>

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idupree
Info I've found so far on rate of water capture:

(MIT, 2011) "In some field tests, fog harvesters have captured one liter of
water (roughly a quart) per one square meter of mesh, per day. Chhatre and his
colleagues are conducting laboratory tests to improve the water collection
ability of existing meshes."

<http://web.mit.edu/newsoffice/2011/fog-harvesting-0421.html>

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ggchappell
If I might channel my inner grumpy-old-man for a moment:

I find it curious that people who design nifty new devices are regularly
referred to as "scientists". This is not science; it is _engineering_. Why not
call it that?

~~~
GuiA
I can't wait to hear what you'll have to say when someone will call themselves
a "computer scientist" ;)

~~~
derekp7
I like what Cliff Stoll had to say about this... "The first time you do
something it’s science. The second time it’s engineering. A third time it’s
just being a technician" -- Ted Talks, 18 minutes with an agile mind.

------
luma
Vaporators! Sir - My first job was programming binary load lifters, very
similar to your vaporators.

~~~
nollidge
IN MOST RESPECTS

------
ipetepete
So, now the real question is: How long until we have a self filling beer
bottle?

~~~
whatshisface
Well, if we assume that any source of alcohol could be counted as beer, this
device could be constructed by combining the water generator with a colony of
modified algae (or an ecosystem of carb leaking algae and yeast) combined with
some sort of membrane that allows alcohol through but not water. (Or a
Brownian motion powered still).

That sounds pretty hard, but it would be a safe bet to say you could buy one
within fifty years. Maybe longer if you want something nicer than pure
ethanol.

------
jmdeldin
This might be the first case of biomimicry on the front page :). This was one
of the entries in our 2011 Biomimicry Student Design Challenge [1]. It's
pretty exciting to see how far they've taken it from concept to funding [2] in
a short amount of time.

[1] <http://2011.biomimicrydesignchallenge.com/gallery> (#38 -- 5 rows from
bottom in center)

[2] [http://ben.biomimicry.net/uni/2012/biomimicry-design-wins-
bo...](http://ben.biomimicry.net/uni/2012/biomimicry-design-wins-boston-
college-venture-competition/)

------
mikek
This is one of those "didn't see it coming" technologies that really has the
potential to change things. Could this disrupt the bottled water industry?
Make it so that water pipes are a thing of the past ("wireless" for water)?

I realize that extraction rates are probably slow right now, but imagine this
technology n years from now.

~~~
Jtsummers
It would be neat to see this used with homes and businesses. Combine with a
cistern for catching rainwater, and use for (at least) the non-potable uses
(laundry, lawn, toilets) and you could significantly reduce the water burden
on reservoirs and aqueducts.

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blahedo
This sounds nifty, but what I'd love to know is, what's the rate of filling,
for an apparatus that's small enough to be roughly bottle-sized? Obviously
many of the technical details (battery size, etc) are still being worked out,
but I'm betting that rate of condensation is already known---and it's an
important constraint.

~~~
Kaedon
Yeah, they talk about using it for runners but how quickly does it fill? Would
it require a full marathon length to fill a single water bottle? It may still
be practical even if that's the case. I'd like to know more.

~~~
Ogre
My first thought was it would be fantastic for backpacking (in high humidity)
if the fill rate is high enough and if it didn't need batteries or heavy solar
panels or anything. Water adds a lot of weight when you have to carry it. If I
could just sip an ounce at a time and not ever have to carry it on my back,
I'd literally be a happy camper.

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tgrass
Disappointed after realizing the title was not: Scientist Creates Self-
fulfilling Water Bottle

------
te_platt
You can see more about collecting water out of the air at
[http://blogs.ei.columbia.edu/2011/03/07/the-fog-
collectors-h...](http://blogs.ei.columbia.edu/2011/03/07/the-fog-collectors-
harvesting-water-from-thin-air/) . Having lived in the Atacama desert I know
there are already ways to do it and am very curious about the efficiency of
this new system. In coastal northern Chile conditions are about as perfect as
possible but it is still a slow process.

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psykotic
Obligatory reference: Fremen windtraps from the Dune novels.

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jayfuerstenberg
This could be good news for farmers who could perhaps create a closed loop
within greenhouses to draw water from the air that the plants originally
exhaled.

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jlgreco
In what ways is this different from existing dehumidifiers? Form-factor and
energy-efficiency I assume, but do they otherwise do the same thing?

~~~
breischl
Most dehumidifiers are basically an air conditioner. They cool down a coil and
draw air over it to cause the water to condense out.

This sounds like some sort of nanotech approach that causes the water to
condense without needing a temperature change. It may not even require any
power, if you can accept a slow rate of water collection.

------
msds
Is it Sorensen or Sorenson? The article keeps switching between the two
forms... As a Sorensen, I will attest that there is a big difference.

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sophie-paul
The air-faucet got broken, want a drink? <http://bit.ly/Y3Op3s>

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moneypenny
This is a fabulous technology, but we shouldn't get carried away. Firstly,
this is another disruption of the world's water cycle, which we have already
managed to a considerable degree, and if we manage atmospheric water
extraction on a massive scale, we will wreak havoc with the climate (again).

 _Note, I said: if we do this on a massive scale._

~~~
ars
And even if you do it on a massive scale nothing at all will happen.

We have these enormous oceans on earth, and if the air gets dry more water
will simply evaporate from the ocean. It takes about a month for air to
completely circle the globe - and a whole lot less than that for air from any
particular place on earth to reach the ocean.

So even if you completely dry out air in one spot it'll be replenished within
a day or two at most. Meaning that overall you never will actually dry out the
air.

And remember that on a global basis water is more or less never created or
destroyed. So any water you capture from the air, will just end up right back
in the air.

You water a plant and it converts the water to hydrocarbons, those
hydrocarbons are then eaten, and are "burned" and are converted right back
into water.

Same for the water you drink - it's only in your system temporarily, it will
end up in the environment again later.

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madrox
Sure, but when can I fund this on kickstarter?

