eli5: Why is it so difficult to desalinate sea water to solve water issues?

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eli5: Why is it so difficult to desalinate sea water to solve water issues?

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17 Answers

Anonymous 0 Comments

One of the reasons is water is very heavy. Desalination plants are set up next to the ocean at sea level. Whatever water you make has to then be pumped, up hill , to where it’s needed. In a place like Isreal that can be a short distance and economically feasible. Trying to get that water over long distances, say from the coast of the Indian Ocean to the interior of Ethiopia would be very expensive. Most water systems try to use gravity for this reason. Dam a stream in the hills, create a reservoir and let gravity bring the water where you need it. What the Romans did. A good argument could be made that we build massive pipelines all over the world for oil, why not for water. I guess we’re willing ( in the developed world ) to pay $5 for a gallon of gas, not yet for H2O

Anonymous 0 Comments

It’s slightly more expensive. It shows you the actual scale of the water crisis. It’s not a non issue but it’s not the type of crisis that typically comes to mind when you hear that word. Agriculture is the most intensive use of water by multiple magnitudes. If the water supply runs down to the point that it’s not economical to perform agriculture they would just quit growing stuff there and grow it elsewhere and truck it in. There’s no need beyond economic benefits to grow almonds and avocados in what nearly amounts to a desert. There is other arable land in the US even. Trucking them across the Rocky Mountains may be expensive though.

Of course there’s a lot more to all of this, this is a very general overview. And it totally ignores all the environmental impacts of every step mentioned above which is not trivial by any means.

Anonymous 0 Comments

Okay there are a lot of answers which all circle back to scale ans costs–but I wanted to add my two cents because IF it could be argued enough you could make the military do it.

I was a 92W, water treatment specialist, they showed us how to run different types of equipment that can make drinkable water at differing speeds etc

You have the Light Weight and then you go to the others. But the process is easy–

Throw out the Dolphin Strainer it pulls in water and keeps out the first large debris, it gets pulled into a Raw Water bag or Tank where a High Pressure pump forces the water through strainers and what ever chemicals are needed to kill bacteria and then it is finally sent to the Clean Water bags. That’s the short and fast process.

They’d would have to go through filters faster because of the salt, but it’s cheaper then the canisters they have to use to clean a chemical attack out of water.

Then to comes back to transportation again but still you have a Trucking MOS.

All the rejected treated water is held in containers because your supposed to dispose of that downstream of where ever your pulling from and certain areas just have rules against dumping the chemically treated water.

Long Story short if anyone suggests a stupid simple idea upper management will explain why it’s not worth it–ignoring that it could fix things temporarily or in the long run.

Like Flint Michigan, nestle set up their factory and is charging them for their own water instead of being charitable.

Anonymous 0 Comments

They do it on cruise ships…. how hard can it be?

Anonymous 0 Comments

I think this is whst Gedaffi was successfully doing in Lybia before America bombed them back to the stone age

Anonymous 0 Comments

Florida has more than 130 desalinization plants. It is the most expensive water that is produced by utilities in the state. The energy needed to push the water through the filters in the reverse osmosis plants is the most expensive component, but the facilities and the filters which must be replaced frequently are also expensive. Plus, an unforeseen expense at the Tampa Bay Plant is the exotic zebra muscles grow inside the pipes, so the plant must be shut down and divers sent inside the pipes to clean the muscles out.

Anonymous 0 Comments

It isnt, but the energy cost is high. And the energy cost will remain high because thats how they maintain control…

Supply + demand. If you dont have scarcity, you make it.