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Simple, solar-powered water desalination

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Re: Simple, solar-powered water desalination

#81

Post by aSplash0fDerp »

The combination of hydrogen production and desalination using simple techniques are an exciting prospect for this decade.

For architects of 21st century cities, most of these sustainable technologies would benefit from a cleanslate design, rather than trying to compete with builtup 20th century infrastructure.

I think Austrailia is postured to be the biggest beneficiary of all of these "leaps" in technology this century. Most of the desert area is the perfect canvas to start building indoor cities that will be the models/prototypes for the spacestations that the next generation will use to explore urban life outside of our atmosphere. Even building a cruise ship on land would be a good starting point for a 21st century city if they could support several thousand residents with enough freshwater for self-sustaining agriculture and energy to take root.

Even though we won't have saltwater in space, most of these advancements in sustainables fit the roadmap to space more than they're currently reported. Hopefully they'll break ground on new cities using these new resources sometime soon and change the narrative appropriately.

Re: Simple, solar-powered water desalination

#82

Post by J5892 »

logfromblammo wrote: post #41
jolmg wrote: post #3

This topic always reminds me of the opening scene[1] from Waterworld where a guy on a raft out in the sea passes his urine through some kind of filter that turns it into drinkable water, and drinks it. I was a little kid when I watched it and wondered why he would drink his own urine when he was surrounded by such vast amounts of water. With this type of technology, maybe he wouldn't have had to do something so gross…

Given the agricultural issues in that movie, perhaps the purification device was intended more to collect and concentrate the urea than to purify the water. But that assumes the scriptwriter would have thought of that, which may be a stretch, given that Earth has insufficient water to cover all landmasses to a depth of 7 km. That would require about 3.6 billion cubic kilometers more water than already exists in the o…

So the only possible explanation of the cause of the Waterworld apocalypse is earth being hit by millions of giant ice meteors.

Re: Simple, solar-powered water desalination

#83

Post by dr_dshiv »

einpoklum wrote: post #66
jfengel wrote: post #39

Earlier quoted context omitted.

I guess it's not really surprising for American engineers. Food and drink are measured in Imperial units. Technical doodads are measured in metric. You don't really need them to be compatible in this case: even though it appears that you're talking about multiples of units of length, you don't really compare them. You're not going to do the calculation that this is "1.58 micrometers per second" or ".447 feet per day"…

> Food and drink are measured in Imperial units. Maybe if you don't mind losing your global Mars orbiter you don't: http://edition.cnn.com/TECH/space/9909/30/mars.metric.02/ _everything_ is measured in metric, period.

Don't forget, 10 hours in a day, 100 minutes in a hour and 100 seconds in a minute (1 metric second = .864 imperial seconds)

Re: Simple, solar-powered water desalination

#86

Post by bluGill »

zamalek wrote: post #40
numbsafari wrote: post #32

Earlier quoted context omitted.

If I am reading [1] correctly, NYC needs approx. 1 billion gallons of water per day. So, they would need an array of 12,500 football fields to meet their needs. [1] https://data.cityofnewyork.us/Environment/Water-Consumption-...

> 1 billion gallons of water per day * How much of that water need be drinkable? * How much of that water can be salinated (e.g. for flushing)? * How much of that water can be partially desalinated (e.g. for showering)?

This doesn't matter as NYC is built on a river that provides plenty of fresh water every year. It needs to be treated and filtered, but at much less cost than desalination.

Re: Simple, solar-powered water desalination

#87

Post by wffurr »

aSplash0fDerp wrote: post #81

The combination of hydrogen production and desalination using simple techniques are an exciting prospect for this decade. For architects of 21st century cities, most of these sustainable technologies would benefit from a cleanslate design, rather than trying to compete with builtup 20th century infrastructure. I think Austrailia is postured to be the biggest beneficiary of all of these "leaps" in technology this cent…

Landships sound like the plot of some dystopian future film; ecosteaders fight off the scavenger bands.

Re: Simple, solar-powered water desalination

#88

Post by RosanaAnaDana »

wffurr wrote: post #87
aSplash0fDerp wrote: post #81

The combination of hydrogen production and desalination using simple techniques are an exciting prospect for this decade. For architects of 21st century cities, most of these sustainable technologies would benefit from a cleanslate design, rather than trying to compete with builtup 20th century infrastructure. I think Austrailia is postured to be the biggest beneficiary of all of these "leaps" in technology this cent…

Landships sound like the plot of some dystopian future film; ecosteaders fight off the scavenger bands.

Clearly you've not passed through northern New Mexico.

Re: Simple, solar-powered water desalination

#89

Post by pytester »

sacred_numbers wrote: post #26

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…

>more cost-effective to use solar panels, batteries, and large scale reverse osmosis systems

I can't imagine why you'd use batteries at all. Storing fresh water efficiently is cheap, storing power efficiently is not.

Re: Simple, solar-powered water desalination

#90

Post by Nasrudith »

wffurr wrote: post #87
aSplash0fDerp wrote: post #81

The combination of hydrogen production and desalination using simple techniques are an exciting prospect for this decade. For architects of 21st century cities, most of these sustainable technologies would benefit from a cleanslate design, rather than trying to compete with builtup 20th century infrastructure. I think Austrailia is postured to be the biggest beneficiary of all of these "leaps" in technology this cent…

Landships sound like the plot of some dystopian future film; ecosteaders fight off the scavenger bands.

It is already - in the my opinion deeply silly book/movie series(?) Mortal Engines. I haven't read or watched them but saw a video ad and thought that it was the stupidest thing I had ever seen. Anyway it is effectively landships except they are massive steampunk mobile cities which grind up and harvest other sessile settlements and smaller mobile ones. I get the extended metaphor involved of colonalism and enrichment by exploitation of the weak and pillaging instead of their own production but even for YA Dystopian it is just too dumb logistically for me to suspend disbelief.
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