Self filling water bottles

[Roll Tide]

Was watching Henry Ford Innovation Nation on TV. They has a segment on a self filling water bottle. It can extract up to .8 l of water per hour from the atmosphere. You can see it at fontus.at (Austria). Its not available now but you can sign up with your email to be notified when it goes on sale.

[Trailweaver]

Bet it could do better than that in the south, with our humidity level as high as it is! :)

[Greenlight]

I've seen the commercials for it, and the .8 liter is under optimal conditions. Looks promising, and the technology has been around for a long time. Imagine hiking for a couple of miles expecting the bottle to be full, and there's only half a ounce of water in there.

[Feral Bill]

I have not yet done the calculations, but I seriously doubt that getting the energy to make this happen is practical. I'll report back.

[Feral Bill]

I'm Back! To condense a liter of water you have to remove 540 Kilo-calories of energy. That equals 627.87 wall hours, or 2,142.381 271 Btu. Not gonna happen, folks, at least not as a portable unit.

[Tuckahoe]

Why do folks buy into this stuff?

https://www.youtube.com/watch?v=Vss1ke5tTvI

https://www.youtube.com/watch?v=aPvXnmBIO7o

https://www.youtube.com/watch?v=-SczCwChCz8

[Feral Bill]

But the principle worked so well on Tatuine in Star Wars!

[Leo L.]

Best part of it is the landscape in the ads video, showing places I will touch during my 3-weeks hike starting tomorrow.

[Frye]

I remember reading about this product a few years ago while trying to keep up with all things cycle related. Back then I think they were only hyping a cycle version of the product that also seemed impractical, and looking at the non-bike version it seems just as useless.

If the product requires 'ideal conditions' to function usefully it should typically be shelved as an useful piece of gear in the backcountry. If it cannot perform its task in a variety of situations, this sort of gear becomes nothing more than a luxury item at best, and a useless brick if the meteorologist gets it wrong... I'm not bringing a product along that is supposed to provide such a vital necessity if I can't have at least some faith in it operating when I need or want it too.

It's like calling a bug bivy a shelter because it'll keep you dry in ideal conditions.

Am I really going to plan an extended route in the backcountry and ignore water sources because I have this product? No, I won't. The company though seems to be making claims to the contrary though, claims I think some could say passes as dangerous hyperbole.


A HIKER MUST EITHER PLAN HIS ROUT IN A WAY THAT HE ALWAYS FINDS FRESH WATER SOURCES, OR HE MUST PACK HIS BACKPACK VERY HEAVILY IN ORDER TO HAVE WATER FOR THE WHOLE JOURNEY. FOOD IS IN COMPARISON MUCH LIGHTER, IF WELL CHOSEN, BECAUSE YOU CAN COMPRESS IT. BUT WATER WEIGHS WHAT IT WEIGHS; YOU DON’T HAVE MUCH OF A CHOICE.
THESE PROBLEMS ARE A GREAT RESTRICTION FOR HIKERS AND OUR MAIN GOAL BECAME TO FIND A SOLUTION THAT WOULD GIVE ADVENTURERS THE FREEDOM TO GO WHEREVER THEY WANT!

I'm sure most of us would take this with a grain of salt, but these are the sort of claims that can get novices in trouble.

[Nodust]

But the principle worked so well on Tatuine in Star Wars!
The mushrooms that grew on the evaporators were worth the effort, evidently.

[Frye]

Best part of it is the landscape in the ads video, showing places I will touch during my 3-weeks hike starting tomorrow.

Is that the video that doesn't actually show the product being used until the halfway point? Some nice shots of it strapped to the pack though I guess...

[Leo L.]

Is that the video that doesn't actually show the product being used until the halfway point? Some nice shots of it strapped to the pack though I guess...

Whenever in the video you watch a hiker or a biker it's in this area.
Biking is illegal there, of course.

Anyway, a nice try to get money from the innocent...
And remembers me on the ADE 651, different category, but similar danger to the innocent user.

[waywardfool]

FOOD IS IN COMPARISON MUCH LIGHTER, IF WELL CHOSEN, BECAUSE YOU CAN COMPRESS IT.

So, they also threw Einstein under the bus? If you compress something, it gets lighter? I guess you are squeezing the dark matter out of it?

[Malto]

Completely unneeded innovation. IT still will weigh more then a quart of dehydrated water. Speaking of which..... I can't seem to find a link to the Mountain House Dehydrated water. I usually buy the water chicken and ground beef in the large #10 cans. Much better value.

[MuddyWaters]

Its certainly theoretically possible.

solar panels , fans, and thermoelectric cooling are all existing technology

The only issues are size, weight, and performance

You are limited of course to about 35F practicle temperature to avoid freezing

So that establishes the minimum % relative humidity you need for it produce any condensate. You essentially have a micro air conditioner, and you drink the condensate drain pan.

At 35 F air will hold 4.4 g water/kg air
At 68F it will hold 15 g water/kg air , this is 100% absolute humidity 4.4/15=.293 = minimum relative humidity
Any less than this, its impossible to condense from the air without temp below freezing.

So, its impossible to work at all at less than 30% relative humidity at 68F.
Low humidity places like western US,NM, Co, Ca, deserts, etc, cool dry weather, winter time, etc. Nada in moderate weather.

At this moment, denver is 96F and 10% relative humidity.At 95F, air will hold 35 g water/kg. 0.1*35=3.5g water , When cooled to 35F, its still not saturated. 3.5 < 4.4 , Will not work, no condensate will occur. Impossible to work.

Where I was in the middle east earlier this year, the relative humidity was 7-9% on hot days. At 104F, air holds 50 g water /kg air.
.08*50=4g water/kg so nope, impossible for it to have worked in the desert in middle east.

All you need to know is how much air it moves and can cool, the relative humidity, the temperature, and you know what water it can produce, and how much power would be needed for a thermoelectric cooler to work, and how big of solar panel would be required. But.. the water and air temperature will likely come now where near to 35F in this little unit, so the require humidity would probably be much much higher.

Water is ~1000 btu/lb roughly.

Some people make a career out of spending other peoples money on things that will never succeed.

[Sarcasm the elf]

I'm Back! To condense a liter of water you have to remove 540 Kilo-calories of energy.

I choose to 1) ignore the bulk of you explanation and 2) Assume that your first sentence means I can simply jam two king size snickers bars into the device and then have it metabolize them into a liter of water. :D:banana

[FreeGoldRush]

I have not yet done the calculations, but I seriously doubt that getting the energy to make this happen is practical. I'll report back.

"Practical" depends largely on your need. As a homesteader it may be great. As a backpacker it is likely useless.

[colorado_rob]

This one is right up there with using "harmonized water" (or something like that) to prevent sunburn. The mind boggles.

[MuddyWaters]

Investigating this a bit further just for fun:

Lets assume the thermoelectric cooler operates at 40F, and air is 86F with 75% relative humidity.
At 40F the air holds 5 g water /kg air
At 86 it holds 27.7 g/kg. So at 75% RH, it holds 20.7. So its possible to condense 15.7 g water out of a kg of air. Or 7.8 g/lb air since I like lbs better.

so to make 1 Liter water = 1000 g takes 1000/7.8 = cooling of 128 lbs air @ 75% RH from 86 f to 40 F, with associated condensation of water

The heat removed from the air is about 128*0.25 btu/lb-F*45F=1440 btu
the latent heat removed from the water is 2200 btu roughly
The sensible heat of the water is on average, only about 50 btu

total heat load would be 3690 btu

thermoelectric would only be about 50% efficient so electrical duty would be 7380 btu to do this in one hr this would be 2163 watts of power required.

Heres the kicker...solar panels produce about 10 watts per sq ft. So lets say this thingy has 2 ft2 solar panel. It makes 20 watts

Your looking at 100 hrs to make a liter of water under optimal conditions

and of course, we didnt include the power required for the fan.

Thats 100 hrs of sunlight for solar power. 8 days ish.

Much of the time, as I described above , it would do nothing at all in many areas of low humidity.

[Feral Bill]

I choose to 1) ignore the bulk of you explanation and 2) Assume that your first sentence means I can simply jam two king size snickers bars into the device and then have it metabolize them into a liter of water. :D:banana
Jam the snickers into yourself and metabolize them into water:)

[MtDoraDave]

Before reading the explanations here, I figured the batteries needed for x amount of time would be just as, if not more prohibitive than carrying water. Solar powered stuff on the AT that is mostly shaded? No thanks.
Filters or chemicals are pretty light weight. Sharper Image types of gadgetry aren't something I would choose to carry on a hike.

[Leo L.]

Anybody knows the woodburning stove named Biolite?
First off (and that's the big difference to this Self Filling Nonsense), it works, so much I can confirm.
But it suffers the same dilemma as described above: While it pretends to have surplus energy you easily could use it to charge your phone while cooking, this does not work. It has only little energy output and to give your (smart-)phone a full charge you would need to keep it burning for very many hours (feeding in wood every 10 minutes and emptying out ashes every hour or so).
And its heavy. The Peltier element contains some heavy cooper pieces and some more.
So its way much easier to carry any lightweight stove you like, and carry a powerbank to keep your phone charged.

This waterbottle thing suffers from both, first it would not work in most circumstances, and second, if engineered in a way that it might work its way too heavy.

I'm sorry for this being Austrian people (names indicate maybe Hungarian or Polish origin though). We usually are no cheaters but pretty straight caracters.

[Connie]

I was thinking only of a filler cap for a water bottle, perhaps a fine screen (not too fine) and a nice attachment for the hiking stick fully extended to reach down an embankment to the water or reach a little further out from the lakeside to dunk under the surfact of the water.

Not precisely a self-filling water bottle..

[atraildreamer]

A self-filling wallet would be a great piece of equipment for a thru-hike! :-? :D:banana

[Sarcasm the elf]

Jam the snickers into yourself and metabolize them into water:)

I'd just end up metabolizing them into methane.:eek:

[CamelMan]

names indicate maybe... Polish origin though).

Hey! We would have gotten the thing to work. But it would be a total patchwork kludge and you'd end up buying the real thing from somebody else for ten times the money. :D

[CamelMan]

A self-filling wallet would be a great piece of equipment for a thru-hike! :-? :D:banana

Mine works just fine. Only fills with receipts, though.

[Leo L.]

And now the Great Invention of a self-filling water bottle goes down the Orkus.
News report, that the guy has changed the design siginficantly, so that it can be plugged into any energy supply, and if investors don't trust the story any longer there could be a refund.
The website is no longer available.

[FreeGoldRush]

This can go into the pack next to one of those miniature water turbines for charging a phone, which is just behind the compartment where you keep the multi-tool, knife set, hatchet, foldable saw, and your hardback copy of War and Peace.

[Dogwood]

Some of yall are missing the pt that no surface water(including snow) may exist in some areas(get your narrow focus off just the AT for a moment!) The wt of the tech might be acceptable to get water from the atmosphere under some conditions?

[Leo L.]

A German survival expert (Ruediger Nehberg) once ran in the hardest desert of the world (Danakil) a series of tests to find out how it would be possible to get water in the desert where there is none.
First he found, that most of the common recommendations like, dig a hole and cover it with plastic, are pure nonsense. You would end up dehydrated faster than you can gather a few drops.
Last he found, that something like Silica Gel could work, given you had a means to heat the H2O out of the Gel. He tried a foldable solar mirror (which he used for cooking anyway).
But thats not for hiking.

[Feral Bill]

Some of yall are missing the pt that no surface water(including snow) may exist in some areas(get your narrow focus off just the AT for a moment!) The wt of the tech might be acceptable to get water from the atmosphere under some conditions?
In the desert, in the summer, it just won't work. Excepting MAYBE places with high humidity but little or no precipitation. Those would not be in North America.

[FreeGoldRush]

Some of yall are missing the pt that no surface water(including snow) may exist in some areas(get your narrow focus off just the AT for a moment!) The wt of the tech might be acceptable to get water from the atmosphere under some conditions?
Areas with no surface water or snow are also the areas with a relative humidity less than 30%. That is why hikers will likely never depend on getting water from the air. But getting water from air might be useful in coastal areas or foggy mountain tops where the energy and infrastructure required to transport small amounts of water uphill are not available.

[Dogwood]

Areas with no surface water or snow are also the areas with a relative humidity less than 30%. That is why hikers will likely never depend on getting water from the air. But getting water from air might be useful in coastal areas or foggy mountain tops where the energy and infrastructure required to transport small amounts of water uphill are not available.

Exactly what I was thinking after recently watching a nature documentary of very arid desert reptiles and insects absorbing tiny condensed droplets that had formed from coastal fog on themselives by heading up to dune ridges in early morn. Kinda neat. The cretures that ate these smaller lizards and insects knew these habits so would wait to ambush them on the way back down from the Ridge knowing they were "juicier" a5 that time.

[LIhikers]

Why not just carry water chestnuts?
Maybe you could even dehydrate them to make them lighter.

[Dogwood]

R they next to the organic dehydrated water tablets?

[RangerZ]

Investigating this a bit further just for fun:

Lets assume the thermoelectric cooler operates at 40F, and air is 86F with 75% relative humidity.
At 40F the air holds 5 g water /kg air
At 86 it holds 27.7 g/kg. So at 75% RH, it holds 20.7. So its possible to condense 15.7 g water out of a kg of air. Or 7.8 g/lb air since I like lbs better.

so to make 1 Liter water = 1000 g takes 1000/7.8 = cooling of 128 lbs air @ 75% RH from 86 f to 40 F, with associated condensation of water

The heat removed from the air is about 128*0.25 btu/lb-F*45F=1440 btu
the latent heat removed from the water is 2200 btu roughly
The sensible heat of the water is on average, only about 50 btu

total heat load would be 3690 btu

thermoelectric would only be about 50% efficient so electrical duty would be 7380 btu to do this in one hr this would be 2163 watts of power required.

Heres the kicker...solar panels produce about 10 watts per sq ft. So lets say this thingy has 2 ft2 solar panel. It makes 20 watts

Your looking at 100 hrs to make a liter of water under optimal conditions

and of course, we didnt include the power required for the fan.

Thats 100 hrs of sunlight for solar power. 8 days ish.

Much of the time, as I described above , it would do nothing at all in many areas of low humidity.


This stuff didn't make sense in college and even less now. Would it help to "seed" the water bottle with a liter or so?

[Leo L.]

And now the company has gone south...

[Deadeye]

They used still-suits on Arrakis, but it seems we've forgotten our Dune history.

[Feral Bill]

This stuff didn't make sense in college and even less now. Would it help to "seed" the water bottle with a liter or so? Afraid not. Another example of the fact that phsyics always wins.