Drought has become one of the talking points talking points. The proverb has not been valid this year (and who knows if it will be valid again) and the month of april has brought neither rain nor water. The reservoirs are close to the 50% capacity mark and in the case of consumptives, the latest hydrological report places them at 41.9% of their capacity.
Immersed in what appears to be a process of aridification, Spain is beginning to follow the example of strategies already used in other environments. One of them may be striking but has become a promise in this context: Atmospheric Water Generation (AWG).
The idea behind this technology is simple: it is capture the water present in the air, atmospheric humidity and transform it fit for human consumption. To do this, it is enough to condense it, filter it to avoid the presence of possible pathogens and mineralize it to make it equal to the water we consume daily.
It is estimated that the atmosphere stores six times more water in the form of moisture than the rivers of our planet, 0.04% of the total fresh water on our planet (68.7% is found in glaciers and other icy environments discovered and 30.1% is found in underground aquifers). Part of this moisture is at ground level and it is, in principle, possible to “collect” it.
Atmospheric water harvesting technology is not new. Until now its use has been limited to pilot projects. The technology is not yet efficient enough, but some improvements in recent years have started to spark interest of some for her.
Efficiency improvements have made it possible to take these technologies to places where it would seem unthinkable. Projects to install panels have been devised for low humidity areas such as Australia or Dubai. They have also been installed deep in the state of Arizona, in the Navajo Nation.
According to data from the industry itself, hydropanels such as those installed in Arizona can produce between two and four liters per day per panel, and under favorable conditions (high humidity and solar radiation) a theoretical maximum of six.
Hydropanels have the advantage of working with the solar energy they capture, but There are other systems that can be used. through electric power. In this field, improvements in efficiency have also broken new ground.
Companies such as Genaq from Cordoba create devices that use heat exchangers to lower the temperature of the air (already filtered to eliminate undesirable particles) below the dew point so that it “releases” the water it contains. This water is again treated to avoid possible pathogens and is drinkable at the outlet.
Efficiency improvements have allowed reach a consumption of 0.22 kWh to collect one liter of waterCarlos García, general director of Genaq, explained in Onda Cero, who also expressed his ambition to reach an efficiency of 0.15 kWh/l by the end of the year.
But it is still not enough to help one of the most affected sectors, that of agriculture. The advantages of this technology are somewhat limited to replacing bottled water and improving the water collection capacities of the most isolated communities.
Eliminating bottled water would imply a significant environmental improvement, but in any case, they would not be able to meet the water needs per person per day, which are estimated at around 50 liters.
exist other alternatives to AWGPerhaps the most important is the desalination of water. Although these technologies have the obvious limitation of having to be located near the coast, their level of energy efficiency is two orders of magnitude higher, with around 0.003 kWh/l.
Desalination systems have a head start, but they are also involved in a race to improve their energy efficiency. This is a more “mature” technology and so efficiency improvements may be slower, but there is still room for ingenuity. In any case, it can be seen not so much as a rival technology but as a complementary one.
Capturing water from the air is a promising technology. Climate pressure and improvements in production and energy efficiency may actually make it viable. in our country sooner rather than later. And what’s more, an industry begins to consolidate to take advantage of it.
In Xataka | Faced with increasingly harsh droughts, we are looking for answers in something discarded 10,000 years ago: perennial cereals.
Image | Jenna Anderson
