More and more people are warning that in general we are going to have a future very scarce in water, and very especially in some areas. And desalination can be a solution in areas close to the sea, which is precisely where most people live.
Desalination consists of obtaining drinking water from seawater, and the most widely used method is reverse osmosis, which, simply put, involves forcing seawater to pass through a semi-permeable membrane that has very small pores, and that retain the salts dissolved in the water. And the water obtained at the end of the entire process is drinkable.
This system is used in more than 60% of the world's desalination plants, but it is not unique.
Another system (called thermal desalination) consists of heating the sea water and generating a steam, later that steam is cooled and salt-free water is obtained. This system is older and is being used less because it is more expensive.
Obtaining water with desalination plants is expensive, and is only done in cases of need, but as temperatures rise and water flows decrease, it will be a way (albeit expensive) to have water to drink.
In the Middle East almost 50% of the water is obtained by these methods, and although some of these countries are rich, it is a shame that they change the desert for land full of grass. It is something typical of the rich, but it does not seem reasonable or sustainable in the future.
Desalination plants are being built in many countries, especially in the USA and China, and for example in California they already have more than 20 of them. It seems that it is a business that is booming.
But as I said before, getting water this way is expensive. A lot of energy is consumed, and when energy is not sustainable, we get water by polluting our environment a little more.
And something negative that desalination has is the generation of “brine” that is polluting and must be eliminated so as not to contaminate the environment.
I am very clear that without water we cannot live, and that we have to get it as best we can, but I am also very clear that we should treat it as a scarce commodity and therefore use it as necessary and not waste it.
It doesn't seem very smart to lay grass in very hot and dry places. I have read that in California they are changing the gardens for others more in line with the climate, it seems intelligent to me and I think that in Madrid we should do something similar.
If viewed from a global perspective, countries should have hydrological plans to make good use of river resources, and other plans to reduce water consumption. It should be something that is taught in homes and schools: that water is the origin of life, something very necessary and scarce, and that we must preserve it for those who come after us.
If it is necessary to build desalination plants, it will have to be done, but not to continue wasting something as wonderful as water that Nature has given us.
The cheapest, easiest and fastest solution is to save on water consumption
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