As we know our earth contains 70 percent of water and 30 percent landscape. In which we know that only 3 percent of 70 percent is drinking water. Population on the earth increasing day by day and our needs and consumption of water is also increasing because it is the main source of our life. But the level of drinkable water decreases drastically due to many factors.
So we need a technology that can convert salty ocean water to the drinkable fresh water, this process is called desalination. This process takes a very large amount of energy which is equal to 10 to 1000 times of pumping water from wells.
Taking this in concern, a team of engineers from the Department of Energy at Politecnico di Torino has invented this desalination technology that uses solar power energy to convert salt water into fresh water. This technology is cost effective because it uses solar power as its energy to perform this task. It also doubles the amount of water production as compared to previous technology.
The principle behind the desalination of water?
This technology is inspired by plants which transport water from roots to leaves by capillarity (Capillary action is the movement of liquid along a surface of a solid caused by the attraction of molecules of the liquid to the molecules of the solid) and transpiration.
How does it work?
The floating device is able to gather ocean water by using a low-cost porous material. thus we can avoid the use of costly and heavy pumps. When the sea water is collected then it will heat up by solar energy, which helps us to separate the salt from the evaporating water. This process can make easy by membranes inserted between contaminated/ mixed water and drinking water to avoid their mixing, just like some plants which are able to survive in saltwater environments.
Researchers said, before this technique we used heavy machines and costly equipment to do this process and require a specialized technique for installation and its maintenance. This desalination process without the need for heavy components is called ‘ passive technology’. This technology highly effective in the coastal regions that are suffering from a chronic shortage of drinking water. the Politecnico’s engineers claim that this technology could have an impact in isolated coastal locations with little drinking water but a good amount of solar energy, especially in developing countries.
The main disadvantage of passive technologies for desalination has been the low energy efficiency as compared to ‘active’ ones. Before we had focused on how to increase the solar energy absorption, we have switched our concern to more efficient management of the absorbed solar thermal energy.
Researchers at Politecnico di Torino take a test of this technology in a coastal area where they got 20 litres of drinking water per square meter exposed to the sun. They make improvement just because of water recycled many times in cascade evaporation processes. This type of process is called multi-effective and they find it in their research. Researchers are still continued with their process in the coaster areas.