A Dune-style stillsuit is thermodynamically impossible. You can't both capture water and use that water to cool you via sweat evaporation. If you let it evaporate, it has to leave; if you capture evaporated sweat you also recover all the heat that it took with it. Those suits are equivalent to going out into the desert with no ability to sweat, and rather than extending your life, would kill you much more quickly.
If they were externally powered you might get the numbers to balance, but they are explicitly presented in the book as powered by the human inside, which subtracts even more time from how long you're going to last in the desert before you die.
You can build a larger thing that recovers your water and cools you via some other method that uses external power, but I think you'd be hard pressed to ever beat just bringing more water with you. It won't be long before you're spec'ing a vehicle and not a suit... and then that vehicle should probably just bring more water, too.
On the more positive front, there is an interesting technology for potentially cooling the Fremen in the middle of the desert that could be based on something real: Paint that cools you by dumping your heat directly into space. Here's a video of it in action and what you might call a prototype of a "suit" that works like this: https://www.youtube.com/watch?v=FnKNOPlR2Yo While that YouTube video shows off someone using that paint on clothes, it seems pretty likely that that would not last very long. Paint on clothes is exactly as silly as it sounds for a long-term approach. But hypothesizing that someone could make clothing or suits based on this approach has the advantage of not being thermodynamically impossible, as evidenced by the fact that at least one substance with these properties actually exists. On Earth, that suit won't work in cloudy weather, but on Arrakis that's not a problem. Tapping the local human power to drive some circulation of either air or a bit of liquid cooling attached to some lightweight fins or some other sort of surface area on your back or something and you might just get a suit that could hugely extend your ability to loiter in a hot desert environment. You'd still need water, but much much less, or, the same amount could take you much farther.
depending on actual conditions you are in, it could potentially double (or more) the time before you die of thirst if it was your only source of water.
Nearly all passive water-from-air devices described in articles are based on false claims. Peltier-based, desiccant/absorption/adsorption based, etc. All end up not working, or not existing. This has been common for ~10 years.
Which category does this fall into?:
- Fraud
- Incompetence / misunderstanding that wasn't cleared up prior to publishing an article
- Neither; this works as expected
The claim on this one is that the textile is supposed to be substantially better than extant desiccants:
> Compared with conventional water-harvesting materials, the textile showed a three- to 10-fold improvement at scale.
Technology Connections has a video on this general technique with a demo from a typical commercially available unit [0]
The "in a jacket" angle is novel... there's no blower. Even though this desiccant may be "3 to 10" times more effective, the passive nature is going to presumably make the rate of extraction quite poor compared to units with a blower to keep moist air moving over the substance.
Based on the wording, this improvement is due to some kind of gradient where moisture is collected on the surface of the jacket/textile, then channeled towards some internal chamber where the desiccant is constantly being heated to extract moisture - without the need to heat the exposed textile to extract water from that portion.
Of course increasing the rate of collection doesn't matter much on its own! You can't drink a damp textile. What takes energy is the removal of the moisture from the desiccant - and how much energy that requires is a detail suspiciously absent from the article (presumably because the efficiency isn't improved versus other desiccants).
So personally, I have trouble imagining this is as efficient as the blower-based commercial units, which are... far less efficient than "normal" compression cycle dehumidifiers (in the above video, real world testing shows the "normal" dehumidifier is 5 times more efficient than the desiccant one).
It isn't passive. The paper states it needs to be heated to 60C and then you extract the water. They use a "DC power source" so you're still putting a battery into the jacket.
If the collecting fabric was on the inside, you'd literally have a stillsuit. I can imagine there would be complications with it getting clogged by oils from the skin.
Plus, you know, completely ruining thermoregulation by preventing heat loss through evaporation.
Assuming it's an "all-weather" jacket I think it would be cool for it to spout out umbrellas when it starts raining, batman style, to catch rain water as well and drop it into pouches. Mp3 player would be great as well.
I know what you're saying and I agree, but now I really want to read a 12 paragraph story about someone's grandmother falling in love in Italy with a plastic bag.
So I assume Amazon will have all their warehouse workers forced to wear these, and collect all the captured water to feed into AI datacenter cooling systems?
I really enjoy that the outbound links go through a redirect on nam12.safelinks.protection.outlook.com (as well as awstrack.me). Did the article author just copy the links they were sent by email without even opening them?
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[ 125 ms ] story [ 531 ms ] threadIf they were externally powered you might get the numbers to balance, but they are explicitly presented in the book as powered by the human inside, which subtracts even more time from how long you're going to last in the desert before you die.
You can build a larger thing that recovers your water and cools you via some other method that uses external power, but I think you'd be hard pressed to ever beat just bringing more water with you. It won't be long before you're spec'ing a vehicle and not a suit... and then that vehicle should probably just bring more water, too.
On the more positive front, there is an interesting technology for potentially cooling the Fremen in the middle of the desert that could be based on something real: Paint that cools you by dumping your heat directly into space. Here's a video of it in action and what you might call a prototype of a "suit" that works like this: https://www.youtube.com/watch?v=FnKNOPlR2Yo While that YouTube video shows off someone using that paint on clothes, it seems pretty likely that that would not last very long. Paint on clothes is exactly as silly as it sounds for a long-term approach. But hypothesizing that someone could make clothing or suits based on this approach has the advantage of not being thermodynamically impossible, as evidenced by the fact that at least one substance with these properties actually exists. On Earth, that suit won't work in cloudy weather, but on Arrakis that's not a problem. Tapping the local human power to drive some circulation of either air or a bit of liquid cooling attached to some lightweight fins or some other sort of surface area on your back or something and you might just get a suit that could hugely extend your ability to loiter in a hot desert environment. You'd still need water, but much much less, or, the same amount could take you much farther.
Which category does this fall into?:
https://www.youtube.com/watch?v=LVsqIjAeeXw
> Compared with conventional water-harvesting materials, the textile showed a three- to 10-fold improvement at scale.
Technology Connections has a video on this general technique with a demo from a typical commercially available unit [0]
The "in a jacket" angle is novel... there's no blower. Even though this desiccant may be "3 to 10" times more effective, the passive nature is going to presumably make the rate of extraction quite poor compared to units with a blower to keep moist air moving over the substance.
Based on the wording, this improvement is due to some kind of gradient where moisture is collected on the surface of the jacket/textile, then channeled towards some internal chamber where the desiccant is constantly being heated to extract moisture - without the need to heat the exposed textile to extract water from that portion.
Of course increasing the rate of collection doesn't matter much on its own! You can't drink a damp textile. What takes energy is the removal of the moisture from the desiccant - and how much energy that requires is a detail suspiciously absent from the article (presumably because the efficiency isn't improved versus other desiccants).
So personally, I have trouble imagining this is as efficient as the blower-based commercial units, which are... far less efficient than "normal" compression cycle dehumidifiers (in the above video, real world testing shows the "normal" dehumidifier is 5 times more efficient than the desiccant one).
[0] https://www.youtube.com/watch?v=JzClLWL-Eys
Plus, you know, completely ruining thermoregulation by preventing heat loss through evaporation.
Wouldn't want to be drinking whatever this produces in the GTA though lol
https://www.campingsurvival.com/blogs/camping-survival-blogs...
https://en.wikipedia.org/wiki/Stillsuit