mdmrjsds

Water: An Ocean of Opportunity

It won't ever happen. A desalination plant only takes a percentage of the water out of salt water. It is too expensive to remove all the water and leave only salt. I believe you are thinking of evaporation, while most of these use reverse osmosis through a membrane via pressure. They have limits on the concentration of salt in the water they will work against.

The concentrated salt water is put back in the ocean 'downstream' of your plant intake. And the water you extract eventually makes its way back to the ocean through evaporation and rain, or sewage treatment, or groundwater, etc. So you are only temporarily separating it, not permanently.

What the article only brushes on and is the main drawback of desalination is the expense. It takes a lot of energy to run the process as you are putting back or reversing the energy of solution. It has been a while since I looked into it, but from memory I think it cost 5 to 10 cents a gallon for treatment when I did. Typical freshwater rates are in the sub 1 cent per gallon range. This water is more like bottled water, used only for drinking, unless you have no other choice. Watering a lawn would be very expensive. In a climate like California or Nevada, it might cost you $500/month for water during the summer using this method if you are a homeowner with a swimming pool and landscape plants. Obviously not feasible for third world countries where that might be yearly earnings.

The true solution to the water crisis (and so many others) is fewer people. Cheaper too. But what are the odds of that? :-(