Can Sea Water Desalination Save The World?

Today, one out of three people don’t have access to safe drinking water. And that’s the result of many things, but one of them is that 96.5% of that water is found in our oceans. It’s saturated with salt, and undrinkable. Most of the freshwater is locked away in glaciers or deep underground. Less than one percent of it is available to us. So why can’t we just take all that seawater, filter out the salt, and have a nearly unlimited supply of clean, drinkable water?

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Can Sea Water Desalination Save The World?

[jamieturnage]

look at the bright side we are never going to run out of salt

[ARepublicIfYouCanKeepIt]

Serving on a nuclear submarine years ago, potable water production was one of my many responsibilities. With essentially limitless energy at our disposal, we operated distillation facilities capable of producing sufficient fresh water for drinking, cooking, washing and laundry, as well as water for batteries and make-up water for the propulsion plant.

After the Navy, I worked on some of the first reverse osmosis membranes, as well as RO plant design, construction and operation.

With that as a background, it astounds me that, as a country, we throw potable water on the ground (a.k.a. watering the lawn). This practice would be unheard of for a large percentage of the world's population. Conservation is key. From non-water intensive lawn/landscapes and agricultural techniques, to vegetarian/vegan diets, to efficient or composting toilets, we need to be better stewards of our natural resources.

Important developments that this piece missed include:
• Atmospheric water generation
• Grey water recycling
• Waste water purification (RO without brine discharge)
• Rain water and run-off reclamation (RO without brine discharge)

As with climate change, there is no silver bullet. Only silver buckshot.

Also, with respect to brine discharge, natural evaporation would partially eliminate other salt mining/production requirements.

[billdavis]

In Western Australia Practically all the energy for our Desalination Plants is provided by Large Wind Turbines which are far from the city in sparsely populated areas The windiest time is in our dry summer which is also when we need the most Water

[kalebbruwer]

In my opinion, the only problem is that river water is artificially cheap. This will cause some tension between inland and coastal cities feeding from the same river, since one of them doesn't have alternatives.

As for the brine, it doesn't sound that difficult to solve. It's literally just concentrated seawater that you need to dilute again. There's a lot of ways to approach that from pre-mixing with seawater to mixing with (treated) waste water.

[mrbruce]

This problem should have been addressed 30 to 40 years ago. Here on the west coast, the people are more worried about their property values than clean drinking water. I remember when the San Diego plant was being built, the people in the next county {Orange County} were so glad it wasn't being built in their county. Now they have a plant going up and they are not very happy with it. Personally, I feel that California could use about 8 to 10 plants along the coast.

[davidhewins]

I'm not a chemist, but am almost certain that more focused research about desalination and filtering would have profitable results. Treating these activities as infrastructure would pay off.

[ebdhudnav]

As I say, "We don't have a water shortage. We will never have water shortage. We will only struggle with how we clean it."

[uweschroeder]

The problem with desalination is scale. Here in California a lot of people who apparently missed basic calculus are pro desalination plants. Leaving energy considerations out of it, the main issues are amount of water needed and amount of salt produced in the process. Ocean water is about 3% salinity. That's a lot of salt. Israel produces about 150 billion gallons of desalinated water per year. California uses about 40 billion gallons of water per day. So what Israel desalinates in a year lasts California 4 days. In the process those 4 days worth of water would produce in the neighborhood of 250 billion gallons of brine - or to put it in perspective roughly 15 million tons of pure salt. The world uses close to 300 million tons of salt per year - for all purposes from food to de-icing roads. That would mean about 20 days worth of California water consumption from desalination would produce the yearly world consumption of salt. Where do you think we're going to dump that much salt after the 20 days?

By the end of the day, desalination is an option for small areas and in California for coastal cities like SD, LA or SF. It's not an option to try to produce enough for agriculture. For California a much better solution to the problem would be to stop focusing on urban water use and reducing agricultural water use. It makes zero sense to produce commodity crops, meat and dairy in a semi-arid region. No, California doesn't need to be the third biggest meat producer in the country, nor does it have to produce 80% of the world's almond harvest at a price of almost 1 gallon of water per nut. Stop producing these things, grow something else that makes more sense for the amount of water that is available and urban water use, which is only 10% of the water used in California, will not matter much.

[steveanthony]

Sell brine to northern states to put on roads.

[GingerO]

I know this may seem like an incredibly simplistic view on the topic but if thermal desalination is the process of boiling and capturing steam for purification. Then, couldn’t you theoretically utilize this steam for energy production? If you combined processes you could reduce infrastructure cost and product costs. Instead of fighting over fossil fuels as much as everyone is. Maybe, we should be enforcing policies relating to mandating water resources

[imperialhistati]

Why not just use the older evaporation and distillation method? Looks safer to me.

[tcmfgamesofficial]

This video makes me appreciate (More than I already do) the fresh water I have here where I live.

[migl]

Nestle: Now how does this affect me and how much can we make off it?

[LegendaryRiot]

I do believe desalination is the key to solving many problems. Although I would rather see the water and salt separate completely in this process and at least some of that salt dumped somewhere environmentally safe to reduce the effects that brine would have on our oceans. More costly, but also healthier. I'm sure with more energy advancements, desalination will become more practical.

[stevefeller]

As the cost of the energy to run the desalination plants would be very high, why not use Thorium Reactors to provide lasting, clean energy from an off the grid source? What issues would need to be overcome to try this type of fuel arrangement?

[nunyabiznez]

I live a few blocks from the harbor. Our water is ludicrously expensive. I live alone and have a small garden. I go to the laundromat to do my laundry. My monthly water bill is $100. This is Florida. It is very expensive here. So I bought dehumidifier and a small solar generator and wired them together. I get about 40 gallons a day which is just enough to keep my garden going on dry days. During rainy season I have a rainwater collection system and a 1000 gallon cistern.

[d.carter]

Video: We must consider other forms of drinking water before considering desalination...
Me: and those are....???
Video: THE END

[MichaelGernold]

Improving water usage habits would definitely help quite a bit. Can't tell you how many I personally know taking unnecessary 30+ minute showers, leaving the water on while they brush their teeth, etc...

[intrusivenature]

We have a desalination plant here in Melbourne Australia. It has cost to date $3.5billion to build since 2012 and $649million of tax payers money to run per year. It can produce enough clean water to supply one third of the Melbourne population but they say that it will probably never be used as we have at least 10 years worth of water.

[dreamlify]

When the documentary lands you more questions than answers.