Atmospheric water generators: The tech-wizardry of making water out of thin air

Water crisis is real. Africa has been through it for decades, Dhaka has seen it first-hand this summer, and Delhi is facing the worst of it as we speak.

Seeing the inevitable global fresh-water crisis, researchers and innovators have been at it for decades, hoping to find a viable and financially feasible way to source drinkable water without needing a water body. Theoretically, it should be easy enough, considering the sheer amount of water we have around us in the air.

In fact, our atmosphere has six times the water we have in all the rivers combined on this planet. This led to several decade-long R&D measures to make water-from-air technology a reality, which resulted in the innovation of several atmospheric water generators (AWG) by multiple teams of researchers and innovators across the world.

AWG, a common term to refer to the device that produces water from the air, extracts humidity or moisture, something we have in abundance in our atmosphere, and then, using cooling technology, condenses the water vapour to collect it as drinkable, fresh water.

Even though these AWGs are energy-intensive, they provide a viable solution for the water crisis in remote areas with no water bodies, limited water supply, and water-ridden diseases or contamination issues. With self-sustaining AWGs run by renewable energy sources like solar or wind power, these options have become increasingly viable in the recent crisis and certainly in the inevitable water shortage in our future.

Different AWGs function a bit differently than the rest, but the core principle is always the same: collect moisture, condensate water vapour, and collect as drinkable water.

This is not particularly a new concept. In fact, it dates back to 16th-century Peru, where people were used to "catching" water by trapping fog into nets and trees.

The collection-condensation process is different, but the raw material, humidity from the air, and produced product, purified drinking water, are similar to the 16th century's "water catching" and are the same for all air-to-water technology now.

AKVO, one of the leading manufacturers of atmospheric water generators, replicates the natural process of condensation by simulating the dew point, which allows them to continuously produce water even in low humidity conditions.

Cody Friesen, the CEO of Source Global and an associate professor of materials science at Arizona State University, has developed hydropanels that are powered by solar energy and extract water molecules to produce drinking water.

The hydropanels have dedicated fans to pull moisture-rich air into the panel, which is then absorbed and trapped in the device. The water molecules accumulated inside the panel are then emitted as water vapour by the heat produced by the solar energy.

This creates a humid gaseous form of water, which is then, using cooling technology like we see in air conditioners and refrigerators, cooled down and condensed into its liquid form.

All of this is done by the solar energy gathered by the panels themselves, creating a self-sufficient and sustained source of water. This moderately self-sufficient water-from-air technology allowed Source Global to expand in more than 50 countries and garner a valuation of S1 billion.

Others, more advanced, bigger and solar-wind-powered AWGs, like Rainmaker's Air-to-Water units, can harvest five to 20,000 litres per day using the humidity in the air, the heat from the sun, and the airflow through the wind turbine.

Portable units like Spout, Atmospheric Water Solutions' water-on-the-go, and Watergen Mobile Box are also starting to break into the market. This year at CES, the world's biggest trade show, Kara Water debuted its Kara Pod coffee machine, which can brew coffee by refilling itself with water collected from the atmosphere. The previous year, it won the CES Innovation Award for its Kara Pure water cooler, which produces up to ten litres per day from moisture in the air using desiccants.

Since almost all of the atmospheric water generators depend on the moisture or humidity in the air and the temperature or heat from the sun, production increases as the climate gets warmer and more humid, which is why warm coastal areas with high humidity are the ideal places for an AWG. But for optimal results, atmospheric water generators must be placed in a well-ventilated area between 21º C and 32º C and relative humidity between 40% and 100%.

Even though these AWGs are energy-intensive, they provide a viable solution for the water crisis in remote areas with no water bodies, limited water supply, and water-ridden diseases or contamination issues. With self-sustaining AWGs run by renewable energy sources like solar or wind power, these options have become increasingly viable in the recent crisis and certainly in the inevitable water shortage in our future.

In fact, this technology can be used to make mankind a multi-planetary species, as researchers are already suggesting AWGs for manned Mars missions where the atmosphere averages 1% water vapour.

As for financial feasibility, the units that rely on external power sources are less so than the ones powered by renewable sources. A study conducted in 2022 on the available AWG units and their use in the UAE yielded 0.18 USD per litre, averaging the year-round cycle.

In separate research by the team at the Autonomous University of San Luis Potosí and Sonora Institute of Technology, Julio, Francisco and their fellow researchers obtained production costs per litre ranging from $0.0093 to 0.038 back in 2019.

However, more advanced and newer models with renewable sources of energy and a lifespan of more than a decade, like Frieson's two thousand-dollar hydropanels, can become a more efficient solution to the water crisis. These panels from Source Global last around 15 years and produce around four to five litres per day per panel. And with their commitment to using advanced machine learning to optimise the process, the company could almost double production.

Home-based AWGs these days typically produce one to 20 litres a day and cost between $1,000 and $5,000, whereas commercial units are capable of ten thousand litres of production per day on average, with an initial unit cost between $10,000 and $1 million.

As of right now, the initial investment and the per-litre cost may seem unfeasible to many, especially to those of us fortunate enough to live in the land of rivers. But in places like Somalia, Djibouti, Kenya, and Eritrea in Africa, where there may not be a single usable water body for hundreds of miles, these atmospheric water generators are nothing short of life-saving.

As the water reserve in the cities continues to deflate, even we, the Dhaka dwellers, might need to resort to these tech wizardries for drinking water. Thankfully, with renewable energy sources powering these AWGs, they will only become more and more economically viable, and the only thing we will need to make our own drinking water is humidity from the air.

But that should not be a problem since there are almost thirteen trillion cubic metres of water in our atmosphere that is constantly replenished by Mother Earth's hydrologic cycle.