Posted on 09/16/2026 12:40:36 PM PDT by TheDon
Summary: Scientists have developed a solar-powered desalination system that turns seawater into fresh water while removing nearly all of the leftover salt as a solid instead of producing harmful brine. The self-cleaning technology could also recover valuable minerals such as lithium, potentially turning desalination waste into a useful resource.
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Scientists at URochester's Institute of Optics created a solar thermal desalination system designed to produce fresh water efficiently without generating liquid brine or requiring chemical additives to pre-treat the incoming water.
The research was led by Chunlei Guo, a professor of optics and physics ...
At the heart of the technology are solar panels made from black metal that has been treated with femtosecond lasers. A femtosecond is an extraordinarily short unit of time, equal to one quadrillionth of a second. Pulses from these ultrafast lasers can precisely alter a material's surface, creating microscopic structures that dramatically change how it interacts with light and water.
The laser treatment makes the metal extremely effective at absorbing sunlight and also gives it superwicking properties, meaning water spreads rapidly across the surface instead of beading up.
Each panel contains a laser-treated active region that draws a very thin layer of seawater across its surface. The dark metal absorbs nearly all of the incoming solar radiation, heating the water and causing it to evaporate.
That evaporation leaves salts and other dissolved minerals behind. Rather than allowing those materials to accumulate where evaporation is taking place, the panel directs them toward untreated areas along its sides, known as the passive region.
This movement is important because salt buildup is one of the biggest challenges facing solar desalination systems. If minerals form a hard layer across the active surface, they can block water movement and eventually stop the system from working.
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(Excerpt) Read more at sciencedaily.com ...
Put AI data centers on floating platforms in the ocean. All the water they need, plus solar power.
Likely as clever as the University of Utah guys’ cold fusion
Vulnerability?
Gold, silver, platinum, copper, fish poop...............Jimmy Hoffa...................
“The newer Sorek B plant has a contracted price around $0.41/m³, which works out to only $0.00155/gallon — about 0.16¢ per gallon.”
Israeli desalinated water is 0.16¢ per gallon. The experimental method here with lasers is prolly 30x as expensive. So can it scale up to be a lot less expensive?
The article didn’t address feasibility in terms of cost.
Is that the one that's been 10 years away from viability for - what it is now? - going on 30+ years?
“Israeli desalinated water is 0.16¢ per gallon. The experimental method here with lasers is prolly 30x as expensive. So can it scale up to be a lot less expensive?”
I suspect, but do not know, that Israeli (and other existing) methods include the amortized costs of dealing with the brine. Which is a big honking pipe under the sea and the associated pumps. The costs are not horrific, but they are not nothing.
They’ll have all the salt 🧂 they’ll ever need!
Israel and other countries have been doing this for a while. Solar panels are perfect because they can work separating the water when the sun shines and turn off when it doesn’t. There is no hurry, the water can wait. As far as the brine is concerned, its just a matter of separating all the water or letting some go back in the sea. There are lots of things in the sea besides salt. But they come in very small amounts.
I believe the lasers are only used in the production of the ‘black metal’. The material then performs the separation of water and other materials. It sounds like a very promising technology.
Theres about 100 pounds of gold in a cubic mile of seawater. The tricky bit is processing a cubic mile of water economically
nothing in the article about:
1. amount of fresh water per hour per square meter of miracle laser-etched superwicking black metal
2. cost of production of a square meter of miracle laser-etched superwicking black metal
3. longevity of miracle laser-etched superwicking black metal
for example, would it take square miles of this stuff to make a reasonable amount of water, costing billions of dollars and lasting only a year before wearing out or whatever?
PHEW!!!! JUST in time... considering that the sea is rising like 100 feet every month!
Isn't 75% of the earth covered with "harmful brine"? What's the problem with it?
Ha! I knew femtosecond was the key! I could have done that myself but I keep forgetting what drawer I keep that femtosecond in. (It kept getting tanged in my string theory so I had to put it away).
“suspect, but do not know, that Israeli (and other existing) methods include the amortized costs of dealing with the brine. Which is a big honking pipe under the sea and the associated pumps. The costs are not horrific, but they are not nothing.”
Yes the price to the consumer is all in, it includes capex, opex and T&D costs too.
Having been to Israel they are the world leaders in desalination and also water recycling tech. Nearly every drop of desal water that hits a drain on that nation is cleaned up and used again for some other purpose farming mainly but industrial cooling is a major use too.
They dispose of the brine by dilution into the Med via high pressure injection arrays offshore the high velocity of the streams cause rapid mixing and no more than 50 meters distance from the mixing array is the ppt back to ambient levels. It’s a total nonsissue and only exists in environmental activists heads as a means to hinder the applications of desal. This is proven tech and when you use large 16” size RO stacks the cost is reduced by a factor of 4.
As a note water is cheaper in Israel from desal vs North Texas municipal water by a factor of 3x cheaper let that sink in. They can make seawater fresh cheaper than the NTX water groups can take lake water and get it to the tap.
Simply put no one touches Israel in desal they lead the world in its tech and implementation.
The very best way to do bulk desal would be to use the waste heat off seawater cooled nuclear reactors. 50C temps drive ethanol carbon absorption chillers to deep sub zero C temps you no longer need to use seawater cooled condenser the evaporator of the absorption chiller is your condenser. Why not just multi stage flash desal you ask. Because the heat of vaporization is nearly 7x the heat of fusion and ice matrix always excludes minerals as in ice is always freshwater when you melt it.
Using the waste heat off of a four reactor pad like the UAE had the Koreans build them would freeze desal more water than the whole UAE uses today by a large margin in fact there would be too much the pipes to carry it would need to be 10 meters across or multiple 60” lines as in a dozen. A literal river’s worth of melt water and so much district cooling could be done you do need to melt all that ice what better way than using building heat in the desert to do so.
A 1.5GW reactor is only 33% into electricity the other 66% is waste heat at 50-70C tens of gigawatts worth for a 4 pad site. You only need 30 to 45 kWh(th)/m^3 of freshwater.
Why?
Freezing water requires pulling out the latent heat of fusion 333kJ/kg, which is roughly 1/7th of the latent heat required for thermal evaporation approx 2500 kJ/kg.
A 4-reactor facility modeled after the massive Barakah Nuclear Energy Plant in the UAE could theoretically produce between 5.5 million and 8.2 million cubic meters(m^3) of fresh water per day entirely from its low-grade waste heat.To put this in perspective, this is enough water to meet the daily drinking and domestic needs of 15 to 22 million people—comfortably exceeding the entire population of the UAE (~10 million).
The more you know.
For real.
“Isn’t 75% of the earth covered with “harmful brine”? What’s the problem with it?”
75% is seawater at 35 parts per thousand , brine by definition is 50ppt or higher. RO brine is 2X seawater at a 50% freshwater recovery ratio its higher at 60 or 70% recoveries.
You cannot dump 60+ppt brine into the ocean as is it will sink being much denser than seawater and form a life killing layer along the bottom and run down slope killing everything it touches it won’t mix on its own it forms a pycnocline the proper term in science.
You must forcibly mix the brine with seawater by a factor of 100 or more to dilute it down to a few ppt above the ambient seawater this makes is no longer lethal to sea life and it will mix further down to ppm level differences in a few hundred meters of additional mixing which is cubic km worth of water volumes if you do the mixing deep enough.
This is exactly how the Israelis make the RO brines harmless otherwise it would be an environmental nightmare. Fish, clams, anything caught in the plume dies from osmosis shock.
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