OK, so we all have heard that many parts of the world are facing, or will soon be facing, serious water scarcity.
At the same time, over 70% of our earth is covered by water.
Why can’t we simply desalinate the water and overcome such scarcity?
Well, fair question, but there are two key reasons why using sea water for large scale water requirements might not be as great an idea as you think.
The first reason is something you would have already guessed yourself: Water scarcity could be in regions that are far away from sea and hence just desalination alone is not enough
The second reason is that desalination is a very energy intensive process and hence makes the desalinated potable water expensive. (Energy costs are almost 60% of the total cost of a desalination plant’s operations!)
So, sure, sea water can indeed be desalinated and made into drinkable water (this is being done at some places such as the Middle East where they can afford such stuff!), but for the common man and woman, especially those who are poor or are far from the sea, they better start finding other ways to overcome water scarcity.
I still vividly remember sitting with a senior Indian bureaucrat a few years back – we both were together putting a list of topics to be discussed at a clean energy seminar an Indian state government was organizing. When I ventured desalination as a topic for the seminar, the bureaucrat immediately said No. He was totally against adding desalination within clean energy as he felt the solution was such an energy guzzler that it can hardly be called clean or sustainable. Well, there are some desalination plants that use solar panels for the electricity they use, but I still agreed with the bureaucrat in principle and did not use that as a topic for the seminar.