Unlimited Fresh Water: Can Glass Domes Save Us?

[@TanyaLairdCivil]

Domes like this are fighting against the square-cube law. The amount of solar energy that falls on a dome is proportional to surface area, or radius squared. The amount of water held in a dome is proportional to its volume, or radius cubed. The bigger the domes, the less surface area each unit of water volume will have to heat it. This is the fundamental problem. Solar stills fundamentally do not scale well. If you really just wanted to do large-scale desalination with solar stills, it might be best to mass produce hundreds of smaller units and just deploy them in fields like we do solar panels, rather than trying to make more impressive giant domes. Go for hundreds of domes 3 meters in diameter rather than one big one 30 meters in diameter.

[@stevelee5724]

Hi Tanya, from New Zealand. Your onto it mate, well put. I reckon you got it right. Cheers Tanya😊

[@off-gridsurvivalmike8120]

That makes total mathematical sense. I am researching atmospheric water generation and stumbled onto this concept.

[@mitchellfolbe8729]

There is math and there is government math. As Mr Hadden says in the movie "Contact", "First rule in government spending. Why build one when you can build two at twice the price?"

[@arnaudthiercelin8631]

I designed something like this.

[@almasysephirot4996]

U.S. utility patent grantee here: Also merely from a common-sense perspective: A better way would be to keep the condensation surface cool (otherwise water will not condensate onto it) is to use the parabolic heat collectors as a sun shield of the condensation system, that is, put the damn thing *below* the heat collectors, run the oil pipes in a small chamber (perhaps buried underground to get extra heat dissipation) pour saline water on the hot pipes, water evaporates, chamber walls cool, and water will condensate onto the chamber wall that they can collect at the bottom into another pipe that draws out cold, fresh water, provided that, the distance from the hot pipe to the chamber wall provides enough surface area to transfer the heat of condensation of the steam upon it contact to the ground-if the pipe is too close to the chamber wall, insufficient surrounding ground may lack the heat dissipation capacity to keep it at an optimal temperature for functioning as a condenser, and assuming the design is a linear installment of individual heat collectors connecting into a single pipe potentially running hundreds of meters, or kilometers with ample room between each of these multi hundred-meter/kilometer long lines to not heat up the ground to allow for the ground to also dissipate the heat, including majorly back onto the surface and out in the air. This design would not run into the square-cube law.

[@Gwanzan3325]

I doubt anything is going to come from Neom except a massive trench, some displaced and executed tribesmen, and huge hole in the Saudi Sovereign Wealth Fund.

[@TheSateef]

but MBS can have any journalists who report on the failure shipped home in small pieces

[@theninearemine8499]

Funding already ran dry for that city.

[@ahowl7mx]

You said the quiet part out loud.

[@1islam1]

​@@TheSateef👉IN ISLAM THERE IS A PURE & CLEAR CONCEPTS OF GOD 🔴 God is One and Unique: God has no partners, no equals and no rivals. God has no father, mother, sons, daughters or wives. 🔵 God alone is worthy of all worship. 🔴 God is the All-Powerful: God has full authority and power over all things. 🔵 Obedience to God does not increase His Power, nor does disobedience decrease His power. 🔴 God is the Most High: There is nothing above or comparable to God. 🔵 The attributes of God do not resemble that of His creation. 🔴 No part of God is present in anyone or anything. 🔵 God is Perfect: God does not have any human limitations, such as resting on the seventh day after He created the universe.

[@Sthuont]

@@1islam1 God is all powerful but needed a person to spread his word through violence? You believe in a lie. The Koran is the word of God uncorrupted yet it contradicts itself so you have the belief in superseding precedence. You believe in a lie. The Koran is the word of God alone yet you base Islamic law on the Hadiths which is the word of Mohammed NOT God... oh and yeah, many of the Hadiths are KNOWN to be fraudulent. You believe in a lie. Islam is uncorrupted by Paganism... yet you all pray to a Pagan shrine 5 times a day... and must undertake a pilgrimage to the Pagan shrine at least once in your life and circle the Pagan shrine where many of you get trampled to death. You believe in a lie. Mecca is even contested as the actual holy city of Islam. You believe in a lie.

[@dropshot1967]

I may have missed you mentioning this, but the M.E.D. installation I worked at used reduced pressure (below atmospheric pressure). Each step was performed in lower pressure to increase the evaporation and the need to add extra heat to keep the process going in each step. Reducing the pressure took less energy than adding heat.

[@pauljs75]

That is a correct approach (if not the optimal one for efficiency), but they should be using a metal water tower instead of some glass dome. Not as pretty, but there would be less problems and more reliability in construction.

[@sendiulo]

Summary: Let’s do desalination. Look at this awesome dome! Forget about the dome!

[@ddegn]

The reason they don't collect water condensing on the inside of the dome is because there isn't anything to collect. The dome would be crazy hot. The water wouldn't condense on the dome surface. They need to move the hot moist air into areas which would be much cooler than the dome.

[@TheCaptainSlappy]

You mean...a de-humidifier, like possibly a small window air conditioner? KEK. And obviously yes. The domes are missing some super basic shortcuts that been around for a century or two, but would basically work. Good thing I did this 15 years ago already, but for flash steam generation. You basically change their dome frame design to be honeycombed smaller transfer pipes, inside a larger one, running to fractal patterns hexagonals about a 1/32nd thick..basically like hexagonal pads that are around an inch or two overall wide, that are your steam boilers. Secondly, you decrease your sphere size to maybe 4 or 5 foot across, to allow for a faster thermal capture, which is passed thru fresnel lenses that create an outer shell around the inner sphere on their own framework (no need to rotate or align) about 2 inches away from the inner sphere. For your fractal pads from the equator down, you basically either leave them as the cooling system like the coil from a still (pre or post slobber box), or use a basic array of mirrors underneath to redirect solar. At that point, you have basically an Archimedes Death Star, that will thermo-siphon from a reservoir, with a slobber box from the steam generator on the return to the center of the inner sphere. That's the overall steam generation design. It was not designed for desalination, though that is easy enough to achieve as a secondary, not primary, goal. It was designed to be fast & cheap. Easy to throw away and replace, or with heavier use units, easy to maintain. The best part, is that within a few generations of real-world re-design, it will put those as being super cheap to produce and use. Possibly even faster than that.

[@laulaja-7186]

Cooler condensation area like… a black painted patch on the top of the dome, under a Saudi desert night sky? Not sure the timing is usable but it might help.

[@puffinjuice]

These domes don't make sense. If you're going to make steam and generate electricity with turbines, you might as well use a thermal tower (existing tech) where the solar energy is focused on an elevated tank of water. The dome is a less efficient way to create steam because most of the solar energy doesn't make it to the water in the ground.

[@GreyDeathVaccine]

But it looks cool and you can scam investors!

[@puffinjuice]

@@Joe-sg9ll I was comparing it to thermal power plants. Thermal powerplants use heat to generate high pressure steam that turns a turbine. I suppose humidity and steam are the same thing, but steam contains a lot more energy.

[@SytanOfficial]

Saudi Arabians dumping an obscene amount of money into something that looks flashy instead of working good? Who would have ever guessed!?!?!

[@callyman]

...and now they've killed it. Gee, that sure was a Massive waste of money - who woulda thought. Hmmm

[@ahmedmani1051]

thats basically what R&D is

[@SytanOfficial]

@@ahmedmani1051 the Saudi's make it their own thing. Research and Dumbvelopment

[@n24913n]

Check out a paper called "Plausible photomolecular effect leading to water evaporation exceeding the thermal limit" which explains how light itself could work to cleave off water molecules and cause evaporation separate to the thermo-evaporative process. In this scenario a dome would likely be less efficient than a long shallow prism might be, light and heat could be reflected into it.

[@artsnow8872]

Yes the research by MIT (Massachusetts Institute of Technology) shows that photons of green light frequency is several time more efficient than infra-red photons (light from the sun, etc.) in causing water molecules to evaporate. This effect is called the "photomolecular effect". Seawater could be preheated in a large, shallow pond. The bottom and sides would be black. The top would be covered with a clear material. This pre-heated seawater would be led into the dome. In, both, the pond and the dome, all the wavelengths of light could act on the water. If there is enough evaporation, the salt could be collected and sold on the salt market.

[@daemenoth]

Yeah this is where desalination is destined to move over the next 5-10 years, that research is a breakthrough in understand how water evaporation behaves.

[@Palisades_Prospecting]

I got a way better idea for desalinization! Imagine black plastic water pipe zigzagging in the desert sand by the shore. The pipe is of equal elevation. One end of the pipe has a pump to pump seawater in and the other end has a reverse P-trap. This end has a pipe on the end of the P-trap that goes back into the ocean then back up on shore. Another smaller pipe is attached to the pipe under the water and all of it is weighted down, this is freshwater outtake. So the water has to get up to 100° to get steam to condense in the Ocean pipe. But with the valves closed there is a vacuum pump connected at the top of the pipe coming out of the ocean. Heat from the sun hits the 3/4 full sea water pipe, vacuum pulls off dissolved gases until it boils at a lower temperature. Once the process starts the vacuum pump can be shut off because the condensed steam will create more vacuum as it turns to liquid. Cheap easy and clean distilled water!😎

[@flutieflambert]

I wish I could follow your description, it sounds great. A video/diagram of how your example functions would really help. Do you have a link to videos or descriptive diagrams? Please and thanks.

[@Palisades_Prospecting]

@@flutieflambert thanks. Try drawing it on a piece of paper I think. The desert sand would be back from the water perfectly dry, gets lots of sun. Area about the size of a football field perfectly flat. lay the pipe in a long row turn it around and come back right beside it and keep going till the field is full. Pipe would probably be a minimum 4 inch diameter where you could do it with pretty much anything larger than that.

[@ameyajadhav7634]

As an engineer only if issue I can see is it's cheap and one cannot over charge the client😂

[@emmakai2243]

You kind of breezed over how the water gets to boiling temperature... This is about desalination via passive evaporation.

[@Palisades_Prospecting]

@@emmakai2243 sry, The vacuum pump pulls approximately 28 to 29 inches of vacuum (no molecular pumps needed). This brings the boiling temperature of the water down to about 30°C. The sun heats the black pipe which heats the water to above 30°. The steam is 30° and rushes to fill the vacuum so it spreads evenly along the pipe up through the P-trap and then down in the pipe that’s under the ocean where it’s cold. Steam condenses with the cold pipe and now you have fresh drinking water that you just need to pump out of the bottom of that pipe. Of course this is without iterations of efficiency.

[@michaelmoorrees3585]

Smart move to leave the Neom project. When that project goes south, heads will literally roll. Best to create as much distance from that fiasco as soon as possible !

[@flutieflambert]

Questions re desert desalination: can the salt/brine be dumped on land into the desert? Would that destroy desert habitats? Can the salt be purified and sold in an economically viable way? Are there other minerals to be extracted from the salt/brine and are those extractions economically viable?

[@artsnow8872]

Yes, those are good questions. There are other minerals, of some value, in seawater. The economics are a hard question for further study.

[@9HighFlyer9]

Deserts in the western US tend to have pretty alkaline soils. Lots of dry lakes are just giant deposits of salts. Plus Great Salt lake in Utah and the Salt River in central AZ are both naturally salty.

[@laulaja-7186]

Yes.

[@no_rubbernecking]

I think desalination is awesome and we need more of it. However, if we're going to go giga or tera with it, wouldn't it perhaps be cheaper and faster to just not let water run into the ocean in the first place, and then treat that water with more conventional methods?

[@andrewday3206]

That sounds good, but the coastal environment actually counts on fresh water discharging into the ocean.

[@no_rubbernecking]

@@andrewday3206 But if we gather seawater, desalinate it, and return the salt to the sea, the effect is the same.

[@andrewday3206]

@@no_rubbernecking Returning the salt is like dumping brine. We sell the salt and remove it.

[@no_rubbernecking]

@@andrewday3206 Sir you are talking about adding megatons of salt to the market per year, over and above the sea salt we already produce. Are you not aware that the great majority of what we already produce is returned to the sea as there is, by a wide margin, no demand for it?

[@artsnow8872]

@@no_rubbernecking There are many tons of salt which is mined, already. If more salt were produced from desalination, less would need to be mined. So, it balance out.

[@pauljs75]

It's even better if they can build an air-tight water tower and use flash distillation inside of it. It doesn't take too many meters of column drop on a gravity drain to lower the boiling point by 50°C, and that's how it would increase efficiency. A purge and vacuum pump system can also help get rid of trapped gases in addition to the main water pumps needed. Instead of the dome, it would be mostly the same as the "bulb" type of water towers already common to the U.S. that acts as a target for reflectors. Most of the changes would be internal with separate internal basins for salt and fresh water and the reinforcement needed to withstand external air pressure as a vacuum is necessary for it to function. The amount of column drop to produce the vacuum draw and the ability to hold water up is technically already in the existing tower design, it's just those things don't operate hot and under a vacuum which would be the main new variables to deal with. Dunno why they're wasting too much effort on making it look pretty and trying to build completely new stuff which makes it more difficult and less efficient. We've had the necessary tech to make a good working system, it's just the matter of bringing the parts together and an implementation that should prove it's possible.

[@fishyerik]

Great analysis! Potentially useful concepts implemented in ways and applications they add more complexity and cost than real benefit (if any) won't save the world. The intriguing thing about the dome shape is that it gives a small surface area for a given enclosed volume, which is great if you need a small surface area for a given volume. But Solar Water seems to be looking for a way to implement the dome shape to address a specific problem, instead of looking for the best ways to address the problem, regardless of if that involves a dome or not. I haven't thought about the fact that besides Saudi Arabia having a lot of money, they also provide the benefit of good excuses to pull out when you can't get your proposed solution to work.

[@chrish3e]

Ziroth, I always admire your video's as being unique, giving great insights in engineering. But this must be an exception, it looks like a bunch of first-graders got together with five rules of knowledge and a good salesteam.

[@Xabraxus]

I'd assume the most efficient way for this idea to work is to lower a heating mantle membrane barely under the surface of the water, with an insulating barrier on the bottom side and holes for water to come up through so that all of the heat is spent heating the small layer of water sitting above it instead of the whole pool. Every once in a while it would need to be scraped as the evaporating water leaves behind a layer of mineral deposits.

[@sveindanielsolvenus]

Distilling water can be achieved with minimal energy by using a flow-through, highly insulated water distiller that integrates an efficient heat exchanger between the feedwater inlet and the condensate outlet. In this system, the incoming cold water is preheated by cooling the opposite-going steam and condensing water, allowing for near-total energy recovery of the heat. The recovery depends largely on the efficiency of the heat exchanger (its insulation and the surface area shared between the opposing streams). Unlike traditional batch distillation, this is a flow-through process, with a small heating element strategically placed at the triple junction where the boiling point, incoming pre-heated water, and continuous waste discharge meet. The steam is allowed to rise straight up through an insulated loop before coming back down and passing by the incoming cool water, as described above. It baffles me why this approach isn't used everywhere we distill water. We can recycle almost all the heat we generate to boil more water, over and over again, simply by optimizing system insulation and heat exchanger efficiency.

[@asimong]

My contribution to this is using wind-powered steam-engine level tech to do vapor-compression, a well-established method of distillation with greatly reduced energy requirements. I would also think it could be extended right the way to extracting a lot of solid sea salt, and taking the minerals from that.

[@Whatneeds2bsaid]

More accessible (i.e. cheaper) desalination is one of those enabling technologies that'll really put us in the future. Research in the process needs to continue, but in the meantime, if we flood the grid with solar energy, desalination seems to be a perfect energy load that we can use to balance the grid.

[@nemorianderson]

So they basically want to boil the olympic pool sized water tank using a steel frame above it and some mirrors. Well, thermodynamics wishes them good luck on that

[@khanyithegreat]

Materials science has left the chat 😂

[@NirvanaFan5000]

Since learning about the problem of leftover brine, I've lost a lot of enthusiasm about traditional desalination. lately, I'm all about atmospheric-water-generation, especially with materials like MOFs, which have SO many potential applications, can be used basically anywhere (including away from water sources), and which don't produce brine waste. (I'm particularly interested in their use for agrivoltaics: You can produce energy, plants, and water all on site with basically no infrastructure. (This could also help revitalize solar land that is degraded. Even if that means just growing grass. The grass helps keep the panels cool, which improves efficiency, and sheep can eat the grass, which can provide food. This would be especially useful in places without sufficient infrastructure.)

[@BD-cm7xc]

A dome is the simplest structure to cover a large area. Arches and domes are a way to keep matter in a compressive state since most materials perform better in compression. This dome is a structural solution to cover a large pool without columns. I think people are confusing the limits of structure materials which force you to use a dome with a glass dome purposely made to heat the matter inside it.

[@aryaman05]

1. Low Temperature Thermal Desalination or LTTD is a far better, as in efficient method. 2. RO with standard PV solar power 3. PV solar power driving Heat Pump to heat seawater in either normal vacuum distillation plant or LTTD. This glass globe is good as fancy greenhouse only. Driving steam turbine from this thing, looking at the surface area alone, can you imagine the forces involved even for a miserly Newcomen type atmospheric engine arrangement ?!!

[@themacker894]

Why make it so complicated. Is the goal to spend money or desalinate water?

[@ddegn]

*"Is the goal to spend money"* Many projects in Saudi Arabia seem to have this singular goal.

[@edwardlulofs444]

The problem to overcome is always wanting more fresh water to come out. As other comments said, nothing (so far) scales up except the whole earth and rain. The bigger the apparatus, the much more cost for a slower and slower increase in water output.

[@chrisflanagan7564]

The goal is to generate investment money from people who don't spot the problems with the designs. Don't get me wrong, I'm in favour of passive desalinization ideas. Sun heats saltwater, increase humidity, capture fresh water is a workable idea... but... ah, here we go, watching the second half of the video, it's a solar heated multieffect desalinization design, "but in a geodesic dome to make it look futuristic to investors"

[@dustinswatsons9150]

I think what that visual concept with the dome and the mirrors is missing is the target tower for the mirrors that's where the steam would truly come about

[@Danothebaldyheid]

Glad to see someone else was so fascinated with this. I kept looking for updates. Sad that it seems to be a non starter. I'd really like to see a reverse river that can create farmland and even wilderness in desert. The best way to store carbon!

[@KyuubiChupachaotica]

It could work if you add rods made from a material that absorbs thermal energy easily. Add an extra set of mirrors and direct the beams from the sunlight onto the rods which should be angled in the salt pool itself. Or a central pole center of the dome with the same concept but the heat wouldn't be as evenly distributed. Although if you add both concepts in the dome design with a little tweaking, theoretically this could work. And you need water catchers like lets say a gutter design that is reinforced. A better catcher design would be a vortex design in the center, Narrows at the center and bottom by an amount, and flares out at the top, and a cistern tub connected at the bottom. It has to be one piece. It does mean with the extra weight that the entire structure would need to be reinforced to compensate and distribute all that extra weight.

[@animistchannel]

Yah, sometimes the rabbit hole ends in a pile of rat droppings... but thanks for checking this out for us! Everything about that system looks like a rube goldberg attempt to defeat thermodynamics. At this point, it really seems like baic solar/wind energy systems plus reverse osmosis is the sensible way to do desalination, especially since that doesn't have to create toxic super-brine byproducts. It's better to pull some fresh water out of a large salt current at small percentages than to try to get max boiling/drying with huge heat wastes to boot.

[@DavidKD2050]

Ironically recently I have been thinking along the same lines. Why, in sunny countries, do we not use solar energy, reflected sunlight, to heat water creating steam, and use this steam in some way? Why wouldn’t it be more efficient than pushing water through filters?

[@pauljs75]

I think RO is pushed because some company can sell an expensive consumable (the RO filters), rather than relying on a method that uses simple industrial tech and is heavily leaning on process controls to operate. Seems like something many smaller equatorial countries could figure out for themselves, but for whatever reasons they haven't been able to kickstart the engineering needed.

[@Kannot2023]

You have to vaporize water, which requires more energy, is more efficient to use reverse osmosis. Energy to remove salt, is lower.

[@alifetomake]

I've run more than 12 000 simulations in my head, and there's not even one in which this dome was a success.

[@juangil384]

He also lacks the envieonment problem of the brine

[@0005yuki]

so much potentially ground breaking technology in this world that i feel like will never get a chance!

[@fk319fk]

There are some exciting developments in this area. I am thinking of a pass-through device made of rows that water flows through and is covered by a long half-cylinder. As the water evaporates, it is collected in troughs on the edge of the cylinder.

[@DominicRyanOsborne]

Is it worth mentioning that whatever funding goes towards fusion also makes it more likely to finally get high volume heating based desalinization going since there's so much more heat generated for that typical plasma vessel

[@FlameofDemocracy]

Green powered dehumidifiers would do that, as well. Place dehumidifiers aloft, and allow water to flow down, into collecting tanks or basins.

[@wadeodonoghue1887]

They should add water absorbing materials around the sides of the dome to draw water up through capillary action to increase surface area for evaporation.

[@karlswanson95]

Here is an idea. My understanding is that supercritical water cannot hold salts, they drop out. This requires high pressure and temperatures. Temperature: The temperature must be above the critical temperature of water, which is approximately 374 degrees Celsius (705 degrees Fahrenheit). Pressure: The pressure must be above the critical pressure of water, which is about 22.1 megapascals (3200 psi or 218 atmospheres). Process would need to go approximately 2,180 meters (about 7,152 feet) below the surface of the ocean to achieve the pressure necessary. Heat can be generated using electricity in a confined area, and by utilizing the rising column of fresh hot water in a pipe, it might be possible to power the process. There is a possibility of generating excess power, although this would depend on the efficiency of the energy conversion process. If enough electricity can be generated to sustain the operation, and if the water is sufficiently desalinated, then the process could be considered viable. However, this approach would likely be limited to locations adjacent to very deep water due to the need for significant pressure, which is a prerequisite for achieving supercritical conditions. I understand that Sydney Australia has water that is deep enough within 45 miles and they currently use desalination for a good percentage of their drinking water.

[@mr.shannon6137]

Death Valley CA. Its below sea level, and one of the hottest places on earth. If a tunnel was made from the Pacific Ocean to there, it would flow without pumps. The intake would need a a few basic/cheap filters. Once in Death Valley the water would flow into shallow swimming pools one feet deep and fully insulated. They would would be covered with a gentle slope towards the center of the pool. There would be an inverted cone in the center of the covering with a collection tube under the point. A closed circuit glycol heat exchanger flowing from the intake to the inverted cone and back again to maximize condensation. You could extrapolate heat from freshwater threw heat exchangers. Shallow insulated and flat bottom for quick evaporation and quich, and easy salt removal. That's my idea. I know it's not tangible, and has many flaws making it not tangible. But I think in the future, people a lot more intelligent than me might be able to figure out a way to make it practical, and possible. Edit: I thought about this some more and came up with a few more ideas. The air temp of Death Valley is often above 115 degrees farenheit. A series of heat conductive tubes could be ran threw the bottom. It would be a closed circuit piping system filled with glycol or other liquid. The piping system would go from underneath the pool to a giant radiator type air heat exchanger with powered fan. A small pump would be required to circulate the liquid. This would use the heated air to heat the bottom increasing efficiency. 2. If a series of pools connected together was built with the top pool elevated slightly higher than the next one. And the pools had zig-zag dividers it would allow continuous flow. The salt water goes threw the first which heats up water, the second which causes it to boil, then the third which finishes the evaporation. Then last a pool to remove all remaining water.

[@jamesquinn3414]

Thanks! Great observations.

[@NickCombs]

The essence of the dome idea seems good: directly solar powered, as simplified and inexpensive as possible. Oil barons aren't gonna do that right, but other leaders could.

[@701983]

It's simple, but doesn't deslinate much water as well. You can't have simplicity and efficiency at the same time in this case. Simple solar stills can make sense in a small scale, but if you want to build something big anyway, you can build a much more efficient solar thermal powered MSF-desalination plant just as well.

[@NickCombs]

@@701983 Not the way they designed it, you're right. But you don't need complexity to concentrate a bunch of mirrors on a tower. We've already seen that with molten salt systems.

[@danieljueleiby914]

I feel like a saw something with how light, by it self (not just it's heat), was responsible for fog and more. Spheres are ofc by design large area and less wall, which might be good for insulation reasons. But ofc : scalability and just throwing more mirrors at the problem might be a cheaper solution

[@richardw5761]

Those domes could be great for farming without mirrors. Some crops can grow in saltwater. Free water plus greenhouse domes could be the best thing ever.

[@daemenoth]

I have a feeling we are going to see much different approaches to desalination over the next 5 years that use light not heating to break up the water. With the recent discoveries on how water can evaporate without boiling. This research has shown that you can evaporate water using less energy by light hitting the water and the light breaking apart grouping of water molecules.

[@demian_csomic_winters9484]

If the dome idea was miniaturized, treated as more alternative water wells or like they could be placed throughout deserts with the ability to collect water from air or rain if a storm comes by then purified by the dome system.

[@701983]

0:15: "... an extremely energy intensive process": That's a question of perspective. Compared to simple distillation, which needs more than 700 kWh of thermal energy per m³, the modern processes like MSF (multi-stage-flash, thermal) and reverse osmosis (electric) are both extremely efficient and energy-saving. And yes, this dome doesn't make sense for big scale desalination.

[@NoPodcastsHere]

Youre missing that in the gen 1 design the heat is conducted through the structure, so water vapor wouldnt condense on the walls as they are the hottest part of the system, rather the vapor would condense back onto the surface of the relatively cooler water below...

[@loiskimberleyplayer]

Fab summary!

[@polyphonics557]

The solar dome idea is a good one.

[@GreyDeathVaccine]

Is good to scam investors.

[@adinb6876]

This dome needs to be redesigned to maximize use of the new;y discovered photo molecular effect-channel the water such that you can light it up at 22.5deg with pure green light.

[@ahowl7mx]

Why desalinate far out in the desert? Just debrine near the coast and pipe in the fresh water.

[@MrRalphla54]

Look at the water towers desalinization designed by the university of Illinois. Much more viable idea and design.

[@apple1231230]

i've had this idea in the past. a better solution is to have a long strait path with a glass triangular structure. WAY cheaper to build, all strait units, and you can scale it very easily, make it wider or longer.

[@TankR]

I could see something like that being possible for evaporation and collection (having made a few my self back in the day. Container with questionable water source, plastic cover with something weighing down the middle, collection pot to catch the drips. Its not fast with just the sun, but its better than nothing!), but steam generation?!?! Aaaaaaaand thats how I knew this was a pipedream from someone who didnt do the maths..... If you want steam, use curved mirrors, pass the water through a pipe at the focal point, and separate steam from salty slurry at the end of each run. But even then you're not going to see much pressure. Also the distillate build up is going to clog and eat up your pipes. Like we discovered when we already tried that in other solar installations. I swear, its like these people make zero effort, hell probably active effort, to not research any attempts at such a process being attempted before. Which is actually a problem in academia and research funding. People assuming the past was dumb therefore not bothering to look up the thing they want funding to research even though, regardless of the $5000 16 channel 64bit DAQ (which they only use 5 channels of...) they want or sensors they have access to, they are capturing data on exactly the same magnitude we have been able to resolve for over a century. As evidenced by the 6 separate papers over that century all displaying the exact same results. But no, the past is stupid, no need to search scientific publications for anything relating to our totally unique and one of a kind idea that we totally arent realizing was a plot point in the movie BioDome, besides we have better computers now, our binary is entirely different from the binary used in the 70s our C is sharper, our assembly more .... assembled (literally none of that is true, computers are just faster and cheaper, not better), STOP BULLYING ME, MY MOM SAYS IM SMART, LOOK AT MY BLACK TURTLE NECK AND GIVE ME FUNDING!!! [insert this weeks societal structural boogyman here]-IARCHY!!!!!

[@chippysteve4524]

When you've got your heart set on something and all you wanna do all day is draw domes..... A soon as you mentioned that NEOM were involved..... Reminds me of the scene in Brewster's Millions where the crackpot inventors make their pitches.

[@FoobarDesign]

By making it THIS complex it will indeed be a engineering nightmare. And taking the enormous amount of land the dome and the mirrors take up in to consideration, it will be more efficient and practical to just use that land for electrovoltaic solar panels (or use mirrors and a tower) to generate electricity and use that for a conventional desalination plant. I mean I actually laughed out loud when the video came to the 'powering steam turbines' part. What a load of crock.

[@greasher926]

It would be more effective if they made a large shallow pond, or a series of ponds, and roof it, similar to how they mine sea salt, but instead of letting that water evaporate into the atmosphere they would collect it.

[@neurofiber2406]

The unexpected problem in these domes, especially in the bottom tank is the algae buildup and clean-up costs.

[@mas13ish1]

I'm not surprised about NEOM falling apart as human rights violations have been sited multiple times by multiple people.

[@cocdcy]

Spheres are a shape that maximize volume while minimizing surface area, so only filling them halfway seems inefficient. Maybe if they had a raised inner tank and relied on condensation on the dome, it would be more efficient

[@AgenteSmart]

Well... no matter how they twist it, the only water they will obtain will be proportional to the heat they scatter to the environment (until that environment grosw too hot to scatter heat as would happen with buried steam pipes, WTF where they thinking?) . Also, contrary to what engineers think, the only variables that matter to the evaporation rate of water are temperature and surface area. Pressure impacts water with dissolved gasses, but once the gasses run off, it's just temprature and surface area. Temperature because individual mollecules must reach 100 ªC and then pack yet another 1,000 calories to acquire enough momentum to move away enough as to break the H-H bond to not one but TWO of their nearest mollecules, and surface area matters because that's only possible when a water mollecule is being held in place by just one other mollecule. That's what humidifiers do by splitting water into tiny droplets with massive surface-to-volume ratio which makes them evaporate faster than larger drops. But that doesn't works with salt water as salt will clog the nozzles quite fast. So all in all, it was a bad idea even before they wasted the inside of the dome as a water collection system.

[@H2oRiz]

Once you learn that the condensed steam isn't even collected, you know they're not serious. They then abruptly leave. Sounds like they are just scammers now.

[@lylestavast7652]

so many variations on this general theme... comes down to cost, environment and simplicity IMO.

[@antoniopacelli]

If you search for California's Solar Energy Small industries they have a Solar Concentration System that would work much better for this Technology... They use it in a Different way.. But the combined Ideas works Wonders... With an Highly Modified Dome Structure and Utilised Materials..of Course.

[@djksfhakhaks]

Your weird facination of spheres is pretty crazy. How do we concentrate light? A SPHERE! How do we make water A SPHERE!!

[@lvlndco]

Seems that sticking with the steeper sloped walls and collecting water running down them plus using the steam to preheat a much shallower pool, and then collecting that fresh water once it condenses would be a simpler and more efficient system. It's almost like they had government funding to throw this idea then that idea into the product without thinking how could it be done efficiently and simply.

[@Golden_SnowFlake]

Dig a trough 100km long, have it fill with sea water, build a roof above it, and have it run off to a side catch outside the trough. This easily solves any and all water crisis's with engineering, done, now can we stop making up fictitious fears about water scarcity? thanks.

[@mystixa]

The dome doesnt make much sense because the point of the condensing surface is to be slightly cooler than the surroundings and come below the dew point. That works ok when gently heating the water in the small versions while heat is carried away from the larger surface area above. With the water in the dome being actively pumped with energy though it will be less difference and less efficient at condensing. It still will, just not super efficiently. It would be better to use the solar collection troughs to heat the pool of water and use something like geothermal cooling loops to cool the air above that pool, and you wouldnt even have to bother with the giant glass dome in the first place.

[@SuperVlerik]

We also need to solve the problem of the left over salt. Can't dump it into the sea, or it will kill the sea life. Maybe create the future's salt deposits with it? It's an overlooked and difficult problem.

[@op4000exe]

There's another option as well, seperate the various salts for minerals we're otherwise mining, and collect them seperately. As for regular tablesalt, ie sodium chloride it would be possible to just collect it, and use the sodium for all the various processes wherein we use that. But honestly I don't think any of these things will happen from a NEOM project, as it is (in my opinion) just a publicity stunt.

[@harrygoldhagen2732]

One issue not addressed is what to do with all that concentrated brine left over from desalination. You can't dump it back in the ocean, it's too concentrated and will kill all sea life at that point.

[@Palisades_Prospecting]

So I think the best way is to pump the brine in a tanker and head out to the deep sea. Because usually these pipes are dumping directly at the shoreline or there’s a longer pipe with smaller holes to help defuse the brine. You take it out in the ocean and you control exactly the rate, concentration of the brine, how you are dispersing it and at what depths. The brine can be cut by more seawater on the ship and the ship can be moving. Regulations need to stipulate the dissipation rate.

[@shirty2]

The water it’s self should be heated through the thermal trough and pumped directly in to the chamber pre-heated.

[@de0509]

Since we are talking solar, imo discussing Liters per day is not good enough. Need to discuss liters per day per meter square.

[@SeanTorres-c1d]

Use a chimney design. Coupled with a solar tower.

[@cx3268]

Here in California who's government WANT the water to be expensive. The host of bureaucracies will put a wall of issues to stop anything like this. This is why for the past DECADE no new desalination plants have been built. Others waiting of government permission (permits) for that DECADE! Their age old issue (for them) is what to do with the salt? Oh package & sell it, no release it back to the ocean.

[@Marqan]

Using mirrors as your main heat source AND a dome doesn't sound like a good idea. If you get most of your heat from mirrors, and not the sun, then you'd want to minimize the surface area that is not heated by the mirrors, to minimize cooling by ambient air or the ground. So if you want an evaporator tank heated by separate mirrors, then I'd imagine you want a flat cylinder that has insulated top and bottom, while the mirrors heating it from the side. But as you said, at that point you're probably better off using a CSP/MED system. Not sure if this video is a complete representation of the actual project, but it seems either the company forgot about some details, or they weren't included in the video. Or this was made specifically for the Saudi project, so it's more about being flashy than actually efficient. My impression is that dome makes sense when you don't have mirrors, or not many, and you want to let the sunlight in for heat, and you use the dome to catch the vapors, AND it's a relatively small structure so dome support is trivial. This is why they are great on small scale, and if you have a lot of cheap and empty land.

[@CarNikola135]

Domes are not the way to go. Saying that at 3:30. If you are going to use it to make el. also, why not just use solar power plants that use molten salt. Just replace molten salt with salty water.

[@whatthefunction9140]

They clearly just want to build a dome

[@atigerclaw]

The first and biggest hurdle I see needing tackling, no matter the system, is: _What do you do with the waste brine?_ That salt has to go somewhere. It doesn't just cease to exist when the water evaporates. And you really, REALLY don't want to dump concentrated brine right off the shoreline into your aquatic ecosystem. It needs to be dispersed back into the ocean or sea it came from. Otherwise, you make some nasty, fast growing brine pools that kill marine life and potentially end up back in your system, and slowly gum it up with saltier, and saliter solution. Which, while it may never approach thick gum or goo levels, will still be the most corrosive agent this side of an acid. I'll leave it to you to imagine the effects ever-increasing salinity would have on the pipes and pumps in this system... ...Spoiler Alert, sailors don't call Rust a 'Fact of Life' to be cute.

[@GreyDeathVaccine]

So basically they invented a new category of scam: water desalination

[@cuiprodest6411]

Those solar mirrors get dirty with sand, and need to be cleaned.. with fresh water ... I wonder if the whole cycle has a positive net outcome (in every resource and cost) or is only for the looks. Seems to me that its a marketing proyect rather than an engineering one

[@monstrositylabs]

More silliness. Odds are in favour of a fail

[@AKA-f7p]

Hmm, why not capture vapours from the sea itself! Those atmospheric water generators need humidity; wright?!

[@zadeify9596]

And anyone who knew something about this, strangely disappeared.

[@proveritate9312]

How will the salty brine be removed to establish a constant flow of normal sea water?

[@ozloop69]

Can I ask this one point is evaporation the rising of the temperature of water to create steam or is evaporation happening prior to the temperature of the water reaching steam point? What is the temperature of evaporating water?

[@yoskkdkdk]

what they’re gonna do with the excess of salt building up? saturate the nearby sea?

[@rqdkaodngos]

Maybe. but not that shape. To achieve sphere shape, a lot of digging and high roof is needed, that is difficult to inspect and repair.

[@unwatchedspacebum]

all of that seems way more complicated than it should be and any time you make something more complicated than it needs to be you get more complications than you need.

[@mikefire98]

So distillation but naturally? I made a science fair project like this in middle school.

[@marioruiz5116]

But, the water that is condensed is actually distilled water, not fresh water because of it not having any minerals and because the proces is basicly a distiller

[@casey6933]

Clearly it was another vanity project - anything that looks cool and future, regardless of efficiency is all Saudi cares about

[@willcabamba8262]

I thought of this 8 years ago..BUT I have a better idea. Cover the outside of the dome with the same plastic film that goes on cars.(. But) REVERSE THE FILM. The sun goes in but can't get out, Rapidly rising the temperature.

[@namethem00]

Maybe you used closed cell nuclear power plant steam condensation... Generate energy with nuclear steam energy, powering turbines, and then exhausted stasm is recondensed into pure water.

[@callyman]

Interesting

[@lefthandedhardright8839]

Just use spent nuclear fuel. The palo verde nuclear plant, uses 6 megawatts to cool the water in the cooling ponds.

[@koreanfarmer1957]

main problem is how to condense the water when outside temperture is scorching hot..??

[@markstipulkoski1389]

Easier to just design a solar powered steam generator. You get the steam for electricity and drinking water. I don't get why this dome concept got off the ground. Maybe to collect some Saudi wealth and skip the country using human rights issue as an excuse?

[@Davidsavage8008]

What movie was that quoting " longer than a Lebanese civil war ?"

[@human_isomer]

concept 1, dome and parabolic mirrors: directing the heat to the structural elements is, besides material issues, total nonsense, because the heat would probably radiate off and do little to heat the water. concept 2, salt-water spray and sequential heat transfer: The heat exchanger pipes would quickly be covered by a, insulating salt crust. There would be concepts where the sunlight may be used much more effectively, with very few moving parts, but these were not shown here.

[@chrisk8208]

The sun is busy evaporating water from a billion sources daily. Why not concentrate on getting the humidity out of the air (particularly in humid environments) instead? New materials are allowing this to be done with little to no external energy input and much smaller footprints.

[@701983]

There are materials that can draw water out of the air pretty well. But then you need a lot of energy to get the water out of these materials again.

[@ped-away-g1396]

well. the idea itself didn't even sound plausible in the first place anyway.

[@javierititin]

Any news on that MIT device?