Here in the US, most of us take clean drinking water for granted as we can turn on our faucets and have access to it whenever we please. For many others around the world, it’s not that easy, and in some cases, it’s nearly impossible to come by water of any kind (clean or dirty). Scientists and engineers have been developing systems that are capable of creating potable drinking water in harsh environments (desert), which is what Berkeley scientists have done with their next-gen water harvester.
They actually field tested their harvesting platform in Arizona last October, and it started sucking the water out of the air without using any electrical power. Granted it was a smaller version, but the functioning principle is the same, and the larger proved that the process still works.
The harvester works by utilizing a metal-organic framework (MOF)- a compound consisting of metal ions or clusters paired with organic ligands. These one, two, or three-dimensional highly-porous structures have a love/hate relationship with water molecules, which is the secret to the harvester. The powdery-crystal-like material holds water molecules in low temperatures and releases them when temps rise, thus perfect for a desert environment.
The harvester functions using a layer of MOF material that’s exposed to air, and as the temperature cools, humidity rises, and water molecules become trapped in the material. As the sun comes up, it heats the material, releasing the water where it’s collected at the bottom of the box and kept cool by a cover. The scientists found they were abler to harvest one ounce of water per-pound of material during the nighttime cycle.
The bad news, yeah it’s nowhere enough for one person to stay hydrated unless the platform is scaled to size. The good news, improvements are already underway as the original zirconium-based MOF material is being replaced with aluminum, which will cost less to manufacture and produce twice as much water. Combine several harvesters together as a modular-like solution and a platform to store the water, and it could provide small communities with clean drinking water in the near future.