Re:Simple, solar-powered water desalination
by _jal on Friday February 07, 2020 @08:31PM
(#22273064)
You can make a solar still without desiccants. Dig a hole somewhere that will get sunlight most of the time, drop a cup in the bottom to catch water, and create a funnel with a plastic sheet. (If you don't have a plastic sheet, branches can work.) There are various ways to optimize it, but a single water trap isn't going to keep a person alive.
Re:Simple, solar-powered water desalination
by ineedasername on Friday February 07, 2020 @09:01PM
(#22273216)
But if they're cheap and easy, and a person could make a dozen, that changes things a bit. But still, I think we're still talking about short term survival only. If that's your environment, the local flora & fauna are unlikely to be prolific enough to fill other needs without extensive effort. Unless, you know, you've got a Still suit and can call giant worms and stuff.
Re:Simple, solar-powered water desalination
by onceUponADime on Saturday February 08, 2020 @08:52AM
(#22275690)
The thing is- this could work without intervention - and without the intention of keeping humans alive for years, thus creating a ecosystem over time. Somewhere in the middle of nowhere- watering cacti, then hardened other plants, reclaiming the moisture they loose, until bushes and trees take over these functions.
Its hard describing this fascination with self-contained or only slowly expanding pockets of life.. imagine a glass bubble , filled with small plants, beatles and life, thriving in the midst of a frozzen over wasteland like mars or a dessert like the death valley.
Its like a https://en.wikipedia.org/wiki/Bottle_garden but without the surrounding walls..
Re:Simple, solar-powered water desalination
by ineedasername on Saturday February 08, 2020 @11:01PM
(#22280325)
To what extent would systems like this extract moisture from the air. siphoning it off from flora/fauna that already make use of it?
Re:Simple, solar-powered water desalination
by numtel on Sunday February 09, 2020 @07:12PM
(#22285317)
There's a newer technology called a metal organic framework that does this at a reasonable rate for the effort.
https://www.youtube.com/watch?v=XPSYzLZ7xKU
https://www.sciencemag.org/news/2019/09/crystalline-nets-har...
A long time ago, as a kid i read about a experiment in a GEO-magazine harvesting water directly from air. The used idea was a hygroscopic chemical (Silicagel) collects the moisture from the air. Sunlight heats the silica gel- which releases the moisture as steam- which then condenses in a destil. It was very little water for a lot of effort, but the complete lack of moving parts and self-containedness of such a system deeply impressed me, being young and with Frank Herberts Dune on my mind.
To drop such a contraption into the deep dessert, where it could keep a plant alive, become a oasis with no basis ..