The American Advanced Research Programs Agency, DARPA, has begun the development of a extractor of drinking water from humidity present in the atmosphere, identified by the acronym AWE for Atmospheric Water Extraction. The program is based on two complementary approaches:
- a vehicle-mounted piece of equipment capable of extracting enough potable water from ambient humidity to supply a force of 150 men in combat.
- individual equipment capable of providing the water necessary for a man in combat
Water indeed represents a major logistical footprint for forces engaged in combat zones, and the logistics chain for supplying these forces with bottles of drinking water is both heavy and very exposed. Giving a force, or each of its members, the capacity to produce its own drinking water, outside the presence of a traditional water source such as rivers, rain or lakes, would therefore represent a definite asset for mobility and autonomy in operation.
To achieve this, DARPA engineers will use new meta-materials capable of absorbing and condensing water present in atmospheric air, using a small amount of energy so as not to replace a logistical problem. by another. This technology comes from work initiated by researchers at the University of Berkley in California assisted by engineers from the Massachusetts Institute of Technology who, in 2017, demonstrated an atmospheric water extractor powered by solar energy. It is based on the use of MOF for Metal-Organic Framework, the association at the molecular scale of metal atoms and organic molecules, creating super-porous materials capable of extracting humidity from the air with very low energy intake.
However, the challenge remains high, in particular to transpose this laboratory technology based on extremely sensitive materials, to equipment that can withstand the harshness of combat missions. In addition, the MOFs used must be able to be used intensively over a sufficient period of time to satisfy this type of use. Finally, the whole thing must be affordable from a budgetary point of view, to hope to enter service one day.
It also appears that if this technology were to be reliable and inexpensive, it could represent a very effective solution for supplying certain isolated populations with drinking water. But if it were to spread, it will also be necessary to assess the environmental effects, particularly on the flora and fauna which survive in desert areas thanks to the humidity in the air collected by dew, for example. Massive extraction of atmospheric water could lead to a drop in humidity levels to such a sensitive point that it could profoundly alter the ecosystem in desert areas.
It is interesting to note that the technology and the way of using it approached by DARPA are very close to the Distillates and the wind traps of the science fiction novel Dune by Franck Herbert, published in 1965. In this saga, the Fremen, an indigenous people from a peculiar arid planet named Arakis, or Dune, use portable equipment to collect water exuded from the body through breathing, sweating, and urine, allowing them to survive for weeks in the desert in extra water. Wind traps and dew collectors are presented as using materials that accentuate the condensation of atmospheric water using the large thermal amplitude of the desert.