Did you know that palatable water can be collected from thin air? No, it's not magic, it's science! Everyday, people all over the world search for new ways to maximize renewable resources, and pulling water from seemingly nothing is one of the groundbreaking methods we have come up with.
This type of technology is called an Atmospheric Water Generator. AWGs are devices that allow for collection of moisture in the air. As of today, collecting water from the moisture in the air is done in two ways-first is through condensation and second through desiccation. In both cases, the principle is the same, similar to dehumidification, but this time, with a potable product water.
Using condensation, a stream of hot and humid air is passed over a cooled coil, usually made of copper, which causes whatever moisture in the air to condensate. Take note that evaporated water is the purest form of water. But as you can imagine, cooling a coil to an extent that the ambient temperature is far higher than the coil's temperature requires a lot of energy. This is why AWGs are often paired with either solar panels or wind turbines-to minimize its operating cost. These solar panels or wind turbines are sized correctly so that they can generate enough electricity when installed with the AWG. Then there are no additional costs incurred for electrical power. With this amount of energy that the device consumes, it is a good idea to install AWGs where the ambient temperature is naturally high.
The more advanced method of desiccation employed in AWG systems, as the name suggests, utilizes a specific type of polymers called desiccants. These desiccants are gel type polymeric materials that are capable of holding a substantial amount of water. A research team in the University of Texas has developed a gel polymer hybrid made of an extremely absorbent material called hygroscopic polypyrrole chloride and an extremely heat reactive material called isopropylacrylamide. Unlike the technique of condensation, desiccation with a hygroscopic hybrid polymer like this can work in both humid and dry conditions. And like the technique of condensation, these hydrogels utilize solar power in order to collect water from the air. In some installations, the solar panels are stuffed with these hydrogels, which are then referred to as "super sponges" due to their ability to hold so much water.
In other cases, a combination of the two methods are employed.
With drought being an uncontrollable threat due to global warming and climate change, this type of technology is a worldwide opportunity for relief.
