The world is on the verge of a water crisis, with freshwater resources expected to decline around 40% by 2030. To solve the issue, experts propose collecting water from the air. Atmospheric Water Harvesters (AWH) might extract the life-sustaining liquid from the air, bringing clean water to underserved populations.
Researchers at X, the Moonshot Factory conceived and built a solar-powered prototype model that replicates the condensation process on a smaller scale. The team made enough water to keep an individual hydrated in various dry environments.
In a report published in the journal Nature, researchers from X, the Moonshot Factory, Google, and UNICEF outlined the process and design of their prototype, claiming that such a device may meet a target average daily drinking water need of five liters per person.
“Ensuring reliable access to safe drinking water for all remains a global challenge and is formally recognized as an international development priority by 2030 in the United Nations framework for global development priorities, the Sustainable Development Goals,” researchers said in the paper.
According to the WHO, 2.2 billion people worldwide do not have access to safe drinking water, 4.2 billion do not have access to proper sanitation, and three billion do not have basic handwashing facilities. According to the UN’s Joint Monitoring Program study, one-third of the world’s population lacks reliable access to safe drinking water. The estimates are sure to rise as climate change exacerbates the problem.
“The scale, severity, and human cost of this problem are one of the reasons teams at X have been hunting for moonshots in the clean water space for many years,” researchers said in a statement. The team found that daytime climate conditions may be sufficient for continuous-mode atmospheric water harvesters operation in the regions with the highest human need.
Researchers have developed a prototype harvester based on the condensation principle. Condensation is the term for the process of turning a gas into a liquid. For example, when warm, humid air collides with cooler air, the molecules slow down and become liquid.
The exact process is responsible for the formation of clouds in the environment. Researchers used this method to build a harvester with a solar heater, air fan, condenser, ambient air fan, and heat exchanger.
The recirculating stream of air on the machine’s top is heated by the sun, and it absorbs moisture from the surrounding air. As it passes through a colder stream of air in the heat exchanger, this humid stream of air cools. The cooled air condenses into liquid, which is collected at the bottoms of the devices, while the remaining air returns to the heat exchanger to be heated, and the cycle continues.
“After three years of work, the team felt confident they could build a device that would produce water for $.10 per liter; however, it would have taken significant development work and iteration to prove feasibility at $.01 per liter,” X stated.
Researchers also provided geographic analysis tools and datasets to help with future AWH implementation and design strategies, and AWH-Geo, to assess where harvesters are most valuable and what outputs work optimally.
While technology advancement is only one part of the complex problem of supplying safe water, the report stated that user-centric research involving a variety of end-users is critical for ensuring that devices are widely adopted.
The study was published in Nature.