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Extraction of water from atmospheric air:
An alternative water source demanding minimal energy consumption

More than 1,500,000,000 people worldwide are suffering from lack of adequate and/or sufficient fresh drinking water – for these 1.5 billion people EWA (Extraction of Water from Air)products is essential solution. According to Population Action International, by year 2025 more than 2.8 billion people in 48 countries will face water deficiency ranging from serious water shortages to major life-threatening crises, unless dramatic solutions are introduced. The number of people without access to piped fresh water accounts for more than 25% of the global population, most of them located in Africa, Asia and South America. According to the International Health Organization, every 8 seconds a child in the developing countries dies from disease caused by unsafe drinking water. The rapid growth of urban and rural populations, industry and agriculture, forces governments to enlarge infrastructures in order to provide fresh water; however, the existing budgets are insufficient for both water treatment (purification or desalination) and installation of pipe-net.
Desalination has long been considered a solution to the world's current and future water problem. Water desalination, has long been utilized by water-deficient nations worldwide to produce or augment drinking water supplies. However, water desalting is limited to places where salty water is available and still needs long-distance pipes to transfer water from the production facility to the consumers.
At any given time, each square kilometer of air, almost everywhere on the globe, contains 10-40 thousands metric tons of water, sufficient to supply at least 100,000 people with all their water consumption or drinking water only for at least 2 million people. Air continue discharged with water that being evaporate form the sea and therefore, this humidity is endless water source!

Extraction of air humidity
Extraction of air humidity as an alternative water source has been known since bible times. The advantages of extraction of air humidity over conventional water sources are: 1) Supply of fresh water independent of existing water resources (sea, brackish water, etc.); 2) No deed for long and expensive delivery (pipe) systems; 3) Unlimited, free renewal of raw material (air) that contains tremendous amounts of water; 4) Suitable for almost anywhere around the globe where water is needed; 5) Compact and portable machinery that could easily be transported; 6) The process does not harm the environment in any way; no chemicals are involved and no wastes are formed; 7) Secured water source.
Air desiccation process in nature is a result of physical interaction between the desiccant and the molecule of the water, and therefore the desiccants absorb water only, and not other air pollutants. The Extraction of Water from Air (EWA) technology combines adsorption by solid desiccants with pressure-condensation and sophisticate energy saving system. Cost effective adsorption of atmospheric moisture and low dependency on ambient relative humidity and temperature are the breakthrough characteristics of this effective method and technology that enable utilization of this enormous water resource. The EWA technology is the sole technology for extraction of water from air having positive energy balance that allows recovery of over 85% of the latent heat and, therefore, enables integrating solar heat as a complementary heat source. Energy must be invested mainly to blow air through the desiccation filters, while the condensation process utilizes the latent heat released upon adsorption, and the heat formed by applying pressure is recovers and returned to the process.
In order to be able to recover most of the energy investing for the process, a multi-stage apparatus was developed, composed of at least three equivalent adsorption units connected to single condenser. At every given moment, one of the units adsorb water from air, one release the water previously adsorbed one is heated up based on the heat form the first unit, that been accumulated in the condenser.
Since most of the energy required to operate the system is heat, it is possible to use biomass, organic waste, waste/residual heat, and even solar radiation, as an energy source. In case of using organic matter, to produce one cubic meter of water only 5kg of dry organic matter are needed to be incinerated. Accordingly, by using agriculture/municipal organic wastes it is possible to supply water for both municipal and agricultural purposes at significantly lower price than alternative water sources.
Due to its effectiveness at extremely wide ranges of environmental conditions and due to its low energy consumption, a water plants with daily water capacity of up to 1,000 cubic meter can be built and operated using the EWA technology, while water cost is equivalent to desalination technologies. Due to the low energy consumption and the possibility of using biomass or organic waste as an energy source it is possible to supply water at reasonable prices without need for long distance infrastructure and at competitive price. The EWA technology, therefore, fulfills the world's desire for available, clean and safe water without requiring for air polluting energy and expensive infrastructure.