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Tags Fontus water bottles , indiegogo

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Old 14th July 2016, 12:36 PM   #41
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Originally Posted by Hlafordlaes View Post
I'm not going to ask about my stuff anymore, but just wanted to say it had nothing to do with Peltier devices. Just for the record, anyway.
I believe your question exceeded the capacity of the remaining expert knowledge base.

I suggest watching the documentary "slingshot" currently on Netflix.
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Old 14th July 2016, 02:52 PM   #42
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Originally Posted by Jrrarglblarg View Post
I believe your question exceeded the capacity of the remaining expert knowledge base.

I suggest watching the documentary "slingshot" currently on Netflix.
Will do.
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Old 14th July 2016, 09:50 PM   #43
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I've gone back to the website for the gizmo and realized it scrolls on and on and on. Like certain kinds of scam pages, for things like a $79 book on solar energy for your home that is an ebook of a pamphlet sized pile low quality information.

Just sayin.


Oh, and that earns them 0.02 TimeCubes as well.
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Old 14th July 2016, 10:56 PM   #44
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Okay, I have a few numbers.

The blue 12v cooler uses a standard Peltier module, specification equivalent to if not actually part # TE-127-1.0-1.5 on this page http://tetech.com/peltier-thermoelec...ules/standard/

The module and fan draw 3-and-some amps on my 6A car battery charger. The fan is a standard 0.17A muffin computer case fan.

Test configuration: box lined with white plastic kitchen trash bag, then filled with 10 pounds tap water in a second bag. Cooler fan inlet and module outlet has been rekajiggered with cereal box and tape ducting to improve airflow efficiency. Power supply is wall AC -> 6A car battery charger -> blue cooler. Cooler covered with (inverted) disposable foam cooler and lid, cut to port outflow air. Test ran overnight.

In cooling mode the air temperature is raised about 10 degrees F drawing heat off the hot side. In Heating mode the air is cooled less than a full 10 degrees.

Cooling run: 15.5 hours, ambient air temp falling from daytime to nighttime outside temps.
Temp drop: 80 to 45F, 35 degrees delta-t, 350 BTU stored, 22.58 BTU stored per hour.

Power consumed: ~3A times nominal 12v equals 36 watts; times 15.5 hours = 0.58KWh

The problem for condensing is that the Peltier module doesn't make cold, it shoves heat.

Performance during tank cooling is limited by ambient temperature capacity for additional heat rise across the fins. Blowing cooler air across the hot fins allows the cold side temperature to drive lower.

During this experiment sequence the tank of cool water was used as a heat receiver to chill air. The air didn't get very cool, the tank temperature rose surprisingly quickly and a small unmeasured amount of condensate drained from the drain gizmo, as designed.

In the Fontus device drawings I can't even figure out where the hot and cold sides are supposed to be. Their airflow and heat flow is all wrong. To condense water from air requires a sufficient, sustained drop in temperature. We can look it up and stuff, but the opposite side of the gizmo gets hot and the heat needs to be pumped off by blowing air at it. In one product the hot thing is inside the lid radiating at your hand, in the other it's hidden inside the clippy solar panel bike mount thing where it may or may not get enough scoop effect through the filter they've added to a passively air cooled device.

To store 350 BTU in cool water the blue cooler consumed almost 2000 BTU of electricity.

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Old 14th July 2016, 11:09 PM   #45
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I won't even get into the magical solar panels.
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Old 15th July 2016, 03:22 AM   #46
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If you read the text from the indiegogo page, there's a bit of waffling on these points. The implication is that they are developing improvements - or intend to (I can't tell).

It appears to me they want to walk a fine line between "known phenomena" and "aspirational." It's a common enough technique seen in scamville. For example, we get a half-hour commercial for some diet product with a disclaimer at the end about not really promising anything at all.

For me, the scam line is crossed with the products offered at each donation level - products that don't actually exist yet.
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Old 15th July 2016, 07:53 AM   #47
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Well, I still don't know if this counts as "scam" or "naive engineering driven by marketing and design." It seems several of these indiegogo projects have been way to far along on plastic cosmetics development for how far they've gotten on mechanics. This is what they're learning somewhere: concept and cosmetics first, organize art and marketing to generate money to build the final project.

Unfortunately this project requires, as I suspected from the start, at least one order of magnitude of improvement to existing power supply capabilities and about an OoM improvement in the heat pump device.

It appears they think they can Manhattan Project their way through engineering with Magical Money. Maybe one or the other parts, maybe, but certainly not both.

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Old 15th July 2016, 12:04 PM   #48
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I call fraud and vexatious ignominity!!!!!!
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Old 15th July 2016, 01:00 PM   #49
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Originally Posted by Jrrarglblarg View Post
In the Fontus device drawings I can't even figure out where the hot and cold sides are supposed to be. Their airflow and heat flow is all wrong. To condense water from air requires a sufficient, sustained drop in temperature. We can look it up and stuff, but the opposite side of the gizmo gets hot and the heat needs to be pumped off by blowing air at it. In one product the hot thing is inside the lid radiating at your hand, in the other it's hidden inside the clippy solar panel bike mount thing where it may or may not get enough scoop effect through the filter they've added to a passively air cooled device.

First, good work on your experiment; such measurements are not easy or simple to make, especially on a budget.

It's hard to tell a lot from their diagrams but for both products it appears both the hot and cold sides of the Peltier module are located within the plenum of air they are trying to cool, which is just plain ridicululous. Maybe worse, for the bike product, the fins of the fin array on the hot side of the Peltier module are not aligned with the airflow.

They claim there is some sort of surface texture or coating on the cold side cooling fins of the module that enhances condensation. I imagine a sharp or fractal microtexture could do this and if there is anything patentable in the design I guess this could be it. Or they might have included this verbiage in an attempt to counter the glaring electrical and thermodynamic issues.

They seem to have spent a lot of time and money mocking up the modules for marketing purposes; a lot more than they seem to have spent on engineering feasibility work. It's hard to see this as anything but a scam.


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Old 15th July 2016, 01:28 PM   #50
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Originally Posted by Jrrarglblarg View Post
Well, I still don't know if this counts as "scam" or "naive engineering driven by marketing and design." It seems several of these indiegogo projects have been way to far along on plastic cosmetics development for how far they've gotten on mechanics. This is what they're learning somewhere: concept and cosmetics first, organize art and marketing to generate money to build the final project.
I like them for skeptical targeting. Exposing them seems useful.
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Old 5th March 2017, 04:10 PM   #51
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Oh dear... looks like they haven't managed to beat the laws of thermodynamics!

https://m.youtube.com/watch?v=wNHcIYyYDhU
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Old 8th March 2017, 01:50 AM   #52
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Originally Posted by Darat View Post
Oh dear... looks like they haven't managed to beat the laws of thermodynamics!

https://m.youtube.com/watch?v=wNHcIYyYDhU
I'm beginning to think that the crowdfunding site should require the sign off of a relevant scientist or physicist before allowing them access. There seem to be to many recent items that rely on being pretty with a slick promo video and everything else is a "solvable technical issue" which keeps getting pushed further down the timeline
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Old 8th March 2017, 04:14 AM   #53
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Originally Posted by Darat View Post
Oh dear... looks like they haven't managed to beat the laws of thermodynamics!

https://m.youtube.com/watch?v=wNHcIYyYDhU
Thunderf00t's calculations are wrong.

The latent heat of vaporization is 2,260,000 Joules per kg. This means you need to remove 2,260,000 of energy from water in order to condense 1 liter from vapor. Thunderf00t has naively assumed that in order to remove 1 Joule of energy from water, you need to spend 1 Joule of energy. This is a coefficient of performance (heat removed divided by energy input required) of 1. But that is not the thermodynamic limit. An efficient refrigerator running at a low temperature differential can remove much more than 1 Joule from a cold reservoir for each Joule of input. The thermodynamic limit for the COP is given by the equation
COP = TL/(TH-TL)
where TL is the low temperature side (where you're sucking heat from) and TH is the high temperature side (where you're dumping heat). Suppose TL = 270 K and TH = 300K, then your maximum theoretical coefficient of performance would be 9, not 1. With a smaller temperature differential the maximum COP goes up, possibly a lot.

Now the real refrigerator they're running isn't going to be perfectly efficient. Moreover, it's also going to be cooling air as well, and that's just wasted cooling. So I do not know if they can actually achieve their performance claims. But I do know, with absolute certainty, that the argument in that video for why they can't is wrong. Thunderf00t badly misunderstand the thermodynamics of refrigeration.

Of course, you can't expect a mere chemist to understand physics.
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Old 8th March 2017, 04:18 AM   #54
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Originally Posted by Ziggurat View Post
Of course, you can't expect a mere chemist to understand physics.
Ohhhh, SNAP!

Physics burn.
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Old 8th March 2017, 12:13 PM   #55
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Originally Posted by Ziggurat View Post
Thunderf00t's calculations are wrong.

The latent heat of vaporization is 2,260,000 Joules per kg. This means you need to remove 2,260,000 of energy from water in order to condense 1 liter from vapor. Thunderf00t has naively assumed that in order to remove 1 Joule of energy from water, you need to spend 1 Joule of energy. This is a coefficient of performance (heat removed divided by energy input required) of 1. But that is not the thermodynamic limit. An efficient refrigerator running at a low temperature differential can remove much more than 1 Joule from a cold reservoir for each Joule of input. The thermodynamic limit for the COP is given by the equation
COP = TL/(TH-TL)
where TL is the low temperature side (where you're sucking heat from) and TH is the high temperature side (where you're dumping heat). Suppose TL = 270 K and TH = 300K, then your maximum theoretical coefficient of performance would be 9, not 1. With a smaller temperature differential the maximum COP goes up, possibly a lot.

Now the real refrigerator they're running isn't going to be perfectly efficient. Moreover, it's also going to be cooling air as well, and that's just wasted cooling. So I do not know if they can actually achieve their performance claims. But I do know, with absolute certainty, that the argument in that video for why they can't is wrong. Thunderf00t badly misunderstand the thermodynamics of refrigeration.

Of course, you can't expect a mere chemist to understand physics.
Did you miss that the company had said it can't produce what it claimed it could and spent thousands reinventing the dehumidifier?


ETA that wasn't meant to be snarky and thanks for your information
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Old 8th March 2017, 12:27 PM   #56
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Originally Posted by Darat View Post
Did you miss that the company had said it can't produce what it claimed it could and spent thousands reinventing the dehumidifier?


ETA that wasn't meant to be snarky and thanks for your information
I stopped after I saw him get the fundamental physics wrong, so yes, I didn't catch that. But it wouldn't surprise me that they have engineering challenges, and as I already said, the flaws in his argument don't mean that they have overcome those challenges. As for reinventing the dehumidifier, well of course they did. Making it small, portable and low power is no small feat.
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Old 8th March 2017, 01:08 PM   #57
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Simple Peltier system? The one side gets 40F cooler than ambient, is that enough for condensation? Depends on dew point?

But I suppose a Peltier and solar panel was the origin of the idea.
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Old 8th March 2017, 01:50 PM   #58
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Originally Posted by Ziggurat View Post
Thunderf00t's calculations are wrong.

The latent heat of vaporization is 2,260,000 Joules per kg. This means you need to remove 2,260,000 of energy from water in order to condense 1 liter from vapor. Thunderf00t has naively assumed that in order to remove 1 Joule of energy from water, you need to spend 1 Joule of energy. This is a coefficient of performance (heat removed divided by energy input required) of 1. But that is not the thermodynamic limit. An efficient refrigerator running at a low temperature differential can remove much more than 1 Joule from a cold reservoir for each Joule of input. The thermodynamic limit for the COP is given by the equation
COP = TL/(TH-TL)
where TL is the low temperature side (where you're sucking heat from) and TH is the high temperature side (where you're dumping heat). Suppose TL = 270 K and TH = 300K, then your maximum theoretical coefficient of performance would be 9, not 1. With a smaller temperature differential the maximum COP goes up, possibly a lot.

Now the real refrigerator they're running isn't going to be perfectly efficient. Moreover, it's also going to be cooling air as well, and that's just wasted cooling. So I do not know if they can actually achieve their performance claims. But I do know, with absolute certainty, that the argument in that video for why they can't is wrong. Thunderf00t badly misunderstand the thermodynamics of refrigeration.

Of course, you can't expect a mere chemist to understand physics.
While the calculation are wrong, it does not matter as even taking into the COP, you need extremely high humidity and a lot of energy which the solar panel cannot give.
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Old 8th March 2017, 09:11 PM   #59
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Originally Posted by Aepervius View Post
While the calculation are wrong, it does not matter
It absolutely matters. Failing for engineering reasons is different than failing because it's not even close to physically possible are not the same thing. Telling people that you can't have a COP better than 1 is just wrong, and spreads false information which can be relevant to other issues (for example, the efficiency of home cooling and heat pump heating).

Quote:
as even taking into the COP, you need extremely high humidity and a lot of energy which the solar panel cannot give.
It doesn't take that much energy, that's the whole point of the COP calculations. And as for requiring high humidity, yes, I've mentioned that problem before.
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Old 9th March 2017, 08:38 AM   #60
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Originally Posted by Ziggurat View Post
Thunderf00t's calculations are wrong. ...

Well spotted. I missed that.

It doesn't change TF's conclusions overall. When applied to the original mock-ups it changes the "takes 40 days to fill the bottle" outcome into something more like "takes 5 days to fill the bottle," which is still not useful for the stated purposes (e.g. to not have to carry water when hiking or biking). And when other realistic inefficiencies are factored in, in low humidity conditions it's back in the 40-day ballpark again.

However, the difference it does make is that it should at least be possible for some kind of solar powered dehumidifier device to be useful under some conditions. The panel and/or the whole device has to be bigger, of course, and maybe you'd need more than one, and to not try to use them in the desert. As one example, I wouldn't mind having a couple of them (per person) along if I were going to be adrift in a lifeboat for a few weeks.
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Old 9th March 2017, 08:59 AM   #61
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The key thing for me was that the product shown in their promo video was very much a concept model, not a working prototype in any sense. In fact, while raising their money they didn't have a prototype, they were still 'analyzing' dehumidifiers.
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Old 9th March 2017, 11:12 AM   #62
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Originally Posted by Myriad View Post
....... I wouldn't mind having a couple of them (per person) along if I were going to be adrift in a lifeboat for a few weeks.
There are simple solar stills as standard equipment on life boats, doing the job of making drinking water perfectly reliably and well. No need for any variation on this electric device.
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Old 9th March 2017, 11:17 AM   #63
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Originally Posted by Ziggurat View Post
It absolutely matters. Failing for engineering reasons is different than failing because it's not even close to physically possible are not the same thing. Telling people that you can't have a COP better than 1 is just wrong, and spreads false information which can be relevant to other issues (for example, the efficiency of home cooling and heat pump heating).



It doesn't take that much energy, that's the whole point of the COP calculations. And as for requiring high humidity, yes, I've mentioned that problem before.
The point is that even with the COP, it still require much more than the solar panel can give, for duration which makes sense.

Again, I don't think he said it was impossible, just that it was non realistic. Even with a COP of 10 it still stays non realistic for the announced expected usage.
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Old 9th March 2017, 12:13 PM   #64
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Originally Posted by Ziggurat View Post
Of course, you can't expect a mere chemist to understand physics.
You'd think a chemist would be familiar with the general idea of Gibbs free energy, though...
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Old 9th March 2017, 02:27 PM   #65
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Originally Posted by MikeG View Post
There are simple solar stills as standard equipment on life boats, doing the job of making drinking water perfectly reliably and well. No need for any variation on this electric device.

These make an interesting comparison to the Fontus devices. They appear to be between about 1/2 and 1 square meter deployed size, and are claimed to produce 0.5 to 2 liters of distilled water per day. Of course, their process is about as inefficient as solar cells + Fontus at utilizing the solar energy, if not more so. The solar still works by heating and humidifying (by evaporation from contained salt water, in the lifeboat models) a closed volume of air inside a plastic dome, and using the ambient temperature on the outside of the volume (including the temperature of the sea surface it's floating in) to cool the interior surface for condensation. The process is slowed/limited by the need for the evaporation. I wonder what their overall efficiency works out to.

They might be simple but they're also surprisingly expensive; my quick searches did not find any priced less than $200 apiece retail. Which is still going to be less than a similarly capable solar electric dehumidifier, but only by a factor of two to five. If the solar electric device is more effective in liters per day yield, it could find a niche in boating (where the necessary high humidity is all but guaranteed) even if it's not as suitable for emergency/lifeboat use (due to its weight, rigidity, fragility) as an easily stored inflatable solar still.
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Old 9th March 2017, 02:36 PM   #66
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Originally Posted by TubbaBlubba View Post
You'd think a chemist would be familiar with the general idea of Gibbs free energy, though...
Free energy?! Who is this Gibbs fellow and how do I get xir's newsletter?
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Old 9th March 2017, 02:49 PM   #67
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http://www.landfallnavigation.com/watermaker.html

Lots of portable desalinators on the market if you are on/near the ocean and need an emergency way to create fresh water.

Lots of portable filters of all sorts to clean up any fresh water you run across so you can drink it.

Not sure why we need to try to add solar cells and electricity to the mix.
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Old 9th March 2017, 02:52 PM   #68
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Originally Posted by Aepervius View Post
The point is that even with the COP, it still require much more than the solar panel can give, for duration which makes sense.

Again, I don't think he said it was impossible, just that it was non realistic. Even with a COP of 10 it still stays non realistic for the announced expected usage.
Last time I checked, the company had one claim about the conditions under which it could produce a liter of water: 2.5 hours at 40 deg. C and 90% humidity. Thunderf00t absolutely said that their claim was physically impossible. He said it would take 40 hours (with a COP of 1), not the 2.5 they claim. His argument is absolutely wrong, because COP can be much higher than 1. At 40 deg. C and a relative humidity of 90%, the dew point is a mere 38 degrees. That permits a COP of about 150, placing the thermodynamic limit not at 40 hours, but at about 16 minutes. Of course, the real system won't work at the thermodynamic efficiency limit, but the difference between 16 minutes and 2.5 hours allows for considerable inefficiencies.

I have serious doubts about the performance of the system because the conditions they quote are extreme, but the claimed performance under those conditions is still plausible.
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Old 9th March 2017, 03:13 PM   #69
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We have peltier dehumidifiers all over the market. We know how much water they can produce from certain humidity levels using a certain amount of power.

Powering them with solar cells isn't going to change the numbers, is it?

http://www.dehumidifierguy.com/ivati...difier-review/
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Old 9th March 2017, 04:23 PM   #70
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Originally Posted by LTC8K6 View Post
We have peltier dehumidifiers all over the market. We know how much water they can produce from certain humidity levels using a certain amount of power.

Powering them with solar cells isn't going to change the numbers, is it?

http://www.dehumidifierguy.com/ivati...difier-review/
Changing the relative humidity and temperature will, though. There's a lot less water in the air with 80% humidity at 86 F (32560 ppm) than there is with 90% humidity at 60 C (70372 ppm), and the difference between the temp and the dew point a lot larger (6.9 deg. F versus 3.5 deg. F) so extracting it is going to be a lot slower and less efficient in the former case. 80% at 86F is a more realistic case, which seems to confirm my doubts about the usefulness of the device, but doesn't directly contradict their quoted performance under extreme (and extremely favorable) conditions.
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Old 20th April 2017, 03:32 AM   #71
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According to the timeline on their IndieGoGo page (https://www.indiegogo.com/projects/f...port-camping#/) they should be shipping out product this month (April). Any bets?

On another front, a different technology that probably actually works to pull water from the air: http://nypost.com/2017/04/14/solar-p...inkable-water/

1) Absorb moisture all night
2) Release moisture all day (with sunlight)
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Old 20th April 2017, 05:10 AM   #72
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Originally Posted by marplots View Post
According to the timeline on their IndieGoGo page (https://www.indiegogo.com/projects/f...port-camping#/) they should be shipping out product this month (April). Any bets?

On another front, a different technology that probably actually works to pull water from the air: http://nypost.com/2017/04/14/solar-p...inkable-water/

1) Absorb moisture all night
2) Release moisture all day (with sunlight)


From the link:

"A person needs about a Coke can of water per day."

Er, off the top of my head, that's a person not doing a lot in a nice, cool environment, isn't it?
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Old 20th April 2017, 05:21 AM   #73
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Originally Posted by 3point14 View Post
From the link:

"A person needs about a Coke can of water per day."

Er, off the top of my head, that's a person not doing a lot in a nice, cool environment, isn't it?
Maybe they are eating a lot of watermelon?

Come to think of it, I don't know how much water I get from solid foods vs liquids. Other than coffee, I don't drink water at all although it seems to be the fashion. I can't imagine a corporate meeting without gratuitous bottles of water all over the place.
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Old 20th April 2017, 05:46 PM   #74
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Your body needs water. The best way to get it is to... drink water.

Anything other than water has additional stuff in it. You may or may not need that additional stuff. You need the water. Some of the stuff may actually be counterproductive. For example, alcohol and caffeine have a tendency to dehydrate you regardless of the water that's also in the drink.

So when you're thirsty, water is by far the best thing to drink. If your town water isn't of good quality (and in a lot of places it's not) then bottled water is your best bet.

Drink other things for pleasure, but drink water for hydration. It's best to stay hydrated. I wrote a thing about this a little while ago that goes into a little more detail about this but in plain easy-to-understand language.
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Old 20th April 2017, 09:01 PM   #75
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Originally Posted by 3point14 View Post
From the link:

"A person needs about a Coke can of water per day."

Er, off the top of my head, that's a person not doing a lot in a nice, cool environment, isn't it?
For hiking or biking on a warm but not hot day, in air neither humid nor dry, my rule of thumb is half a liter of water per hour.

In cool weather, a fit person can run a three-hour marathon without water. On a warm day, that's asking for trouble. On a hot day, running for three hours without water is asking for serious trouble.
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Old 21st April 2017, 01:24 AM   #76
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Originally Posted by arthwollipot View Post
Your body needs water. The best way to get it is to... drink water.
Why don't we say this about other things? I need Vitamin C and the best way to get it is to eat Vitamin C. I need salt. The best way to get it is to eat salt.

Generally we are not so focused and I submit the attitude in the US about drinking water has changed over the last few decades and is mostly not justified scientifically, but simply a fad. There's the ubiquitous bottle of water as an accessory people carry around. There's the glass of water the waitress brings you, usually without asking. Store shelves are full of various brands of water.

When I was a kid, we drank water when we were thirsty - from the tap.

Quote:
Anything other than water has additional stuff in it. You may or may not need that additional stuff. You need the water. Some of the stuff may actually be counterproductive. For example, alcohol and caffeine have a tendency to dehydrate you regardless of the water that's also in the drink.
Alcohol yes, depending on the strength of the drink. Caffeine no, at least not for those acclimatized to drinking it.

Have you ever looked at how much water is in the normal foodstuffs you eat?

And then there's metabolic water (from Wiki):
"Metabolic water refers to water created inside a living organism through their metabolism, by oxidizing energy-containing substances in their food. Animal metabolism produces about 100 grams of water per 100 grams of fat, 42 grams of water per 100 g of protein and 60 grams of water per 100 g of carbohydrate."

I don't have anything against water, but it's not necessary to go out of your way to drink it or fear dehydration in the normal course of affairs.
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Old 21st April 2017, 06:25 AM   #77
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It seems like if there is enough moisture in the air for these devices to produce a useful amount of water, then you don't need the device because water is readily available. There is either a water source in the area, or it rains a lot in the area, or both.
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Old 21st April 2017, 06:36 AM   #78
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Originally Posted by LTC8K6 View Post
It seems like if there is enough moisture in the air for these devices to produce a useful amount of water, then you don't need the device because water is readily available. There is either a water source in the area, or it rains a lot in the area, or both.
If the source of water is the ocean, that's not really available.
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Old 21st April 2017, 06:40 AM   #79
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Originally Posted by marplots View Post
I don't have anything against water, but it's not necessary to go out of your way to drink it or fear dehydration in the normal course of affairs.
If I'm not doing physical work, I usually won't drink any water during the day. I drink a fair amount of milk, occasionally tea, but not plain water.

When I exercise, I do drink plain water.
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Old 21st April 2017, 07:17 AM   #80
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Originally Posted by Ziggurat View Post
If the source of water is the ocean, that's not really available.
It does seem as if a device of this nature would be a natural for a coastal region or for a boat, doesn't it?
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