American researchers have devised a system that enables the capture of ocean water vapor in order to convert it into drinking water, in an effort to find sustainable solutions, while many countries are facing water scarcity due to the consequences of climate change and successive dry seasons.
“We believe that the system we proposed can be adopted on a large scale,” said Praveen Kumar, a professor at the University of Illinois and one of the authors of the study published on December 6 in the journal Nature.
He and his colleagues think that the evaporation of ocean water, which is enhanced by the rise in temperatures, can serve as reservoirs for drinking water. Instead of evaporating into the atmosphere, waterlogged air would be captured by special offshore facilities, before being condensed and piped to be stored and redistributed.
What distinguishes this process from that related to water desalination is that sea water, through evaporation and conversion into gas, loses almost all the salt it contains naturally, and for this reason, rainwater is not salty.
In the innovative method, treatment requires less energy and results in much lower environmental impacts than current methods (brine, wastewater containing heavy metals).
Scientists confirm that offshore wind farms and onshore solar panels can be used to power this system.
The co-author of the study, who specializes in the atmosphere, Francina Dominguez, indicated that this technology reproduces the natural cycle of water, but “the only difference is the possibility of managing the destination of evaporated water from the oceans.”
The researchers said that a vertical capture surface 210 meters wide and 100 meters high could provide a sufficient volume of extractable moisture to meet the daily water needs of about 500,000 people.
This data was obtained following simulations conducted on 14 water-stressed sites located near major population centers such as Chennai in India, Los Angeles in the US and Rome in Italy. Based on the models, this type of system can produce between 37.6 and 78.3 billion liters of water per year, depending on the conditions of each site.
Afifah Rahman, co-author of the study, said, the projections related to climate issues show that the flow of ocean water vapor will increase over time, providing more quantities of fresh water, which constitutes an effective and very necessary approach to adapting to climate change, specifically for the populations living in the regions that witness complete or limited drought.
