Elon Musk, today's version of Ben Franklin or Thomas Edison, has been quoted as saying desalination of water has become "absurdly cheap." Of course, when you have his money everything is absurdly cheap, but a Brit who likes to search statistics and crunch numbers has decided to see if he is correct for the rest of us.
It turns out to be true for developed countries, if you're talking about household water for drinking, washing, etc. Less so for poor countries.
Here’s the surprising figure. Producing enough drinking water for someone — assuming 3 litres per day — costs just $2.30 for the entire year. That’s less than the cost of a single bottle of water in many countries.
Where it becomes absolutely not true is when you factor in agriculture which uses most of our fresh water. Using desalinated water for agriculture would double or triple the cost of basic food stocks.
It might just be economic in fringe cases for high-value crops, grown in conditions that are much more water-efficient — such as indoor farming — but we’re still pretty far from having solutions that could make a big dent in meeting water demand for staple crops.
In other words, dope farmers could make it work; corn and wheat farmers, and ranchers of meat animals not so much. Food production will have to continue to utilize naturally occurring sources of fresh water.
Caveat: As the author notes, she made some unrealistic assumptions, like we will get all of our water from desalination. Obviously we never will. It isn't going to stop raining and snowing, ask the folks in North Carolina, who wish for less of nature's bounty.
