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Simple, solar-powered water desalination

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Re: Simple, solar-powered water desalination

#201
post #45

Earlier quoted context omitted.

What, per millifortnight? cf. https://news.ycombinator.com/item?id=22270160

How much water can I get in a moon?

If by 'moon' you mean our Moon, it has a volume of 2.1958×10^10 km3. Although, how much of that will hold water, we don't know. Anyway, a jerrycan is probably a lot more convenient ... holds 4.4 imp gals.

Re: Simple, solar-powered water desalination

#202

Earlier quoted context omitted.

How much water can I get in a moon?

If by 'moon' you mean our Moon, it has a volume of 2.1958×10^10 km3. Although, how much of that will hold water, we don't know. Anyway, a jerrycan is probably a lot more convenient ... holds 4.4 imp gals.

> 4.4 imp gals

That's 0.062 cubic Flemish ells, for those who were wondering.

Re: Simple, solar-powered water desalination

#203

Earlier quoted context omitted.

How much water can I get in a moon?

If by 'moon' you mean our Moon, it has a volume of 2.1958×10^10 km3. Although, how much of that will hold water, we don't know. Anyway, a jerrycan is probably a lot more convenient ... holds 4.4 imp gals.

I really meant a month, but that was good :)

Re: Simple, solar-powered water desalination

#204

Earlier quoted context omitted.

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.

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.. ima…

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

#205

Efficiency in desalination is measured by comparing the energy expenditure to the enthalpy of vaporization of water (basically the energy required to distill water by boiling it). The current state of the art reverse osmosis desalination plants use about 3.2 KWh of electricity per cubic meter of fresh water ( https://pdfs.semanticscholar.org/d4d7/821d585699719289dddd10... ). This technology uses about 173 KWh of sola…

Regarding remote locations- they usually lack water altogether. 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 comp…

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...

http://wahainc.com/

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