There is plenty of clean fresh water in the air. The trick is extracting it. Developers of the WaterSeer say they have made strides reducing the cost and simplicity of a device that does exactly that and in a nearly passive process. It relies on the temperature difference between the above-ground air and the cooler temperatures a few feet below ground. Early designs used a small vertical axis wind turbine to provide a few watts to drive a fan that improves performance but later models use solar power.
Previous condensation devices relied on processes similar to that in air conditioners: compressing a thermodynamic fluid, expanding it in a copper coil, and collecting the condensate − the water that collects on the cool pipes. These relatively complex devices, although powered by wind-generated electricity, were expensive and required skilled maintenance.
The WaterSeer gets rid of the air conditioning equipment and uses the earth for the temperature difference. Its design looks like a cylinder about 10-in. diameter and 8-ft long. The device is buried so that about two-thirds of it is below ground. An internal fan above ground pulls moisture-laden air into a collection chamber where the vapor condenses and collects in a pool at the bottom. The company says the yield is accelerated by a proprietary hydrostatic feedback system, new material applications, constant below-ground temperatures, and solar-powered coolers. The company add that the device continuously produces water for less than 100 watts/liter.
Recently, the company announced a successful first round of field tests. Some results are presented in the following table.
The company also said in an email that intake and exhaust vents have insect resistance screens to limit entry by dust and debris. The water at the output is filtered through a commercial filtration module. What’s more, the WaterSeer water quality before filtration exceeds EPA and WHO standards for drinking water and is completely free of metals, nitrates, nitrites, and bacteria. Here are the results of the field water quality test:
“Water from the air is the next source of water for the world. We will continue to improve the design over the next month and years to increase efficiencies and yield. We will not be satisfied until everyone everywhere has water security and independence” said Nancy Curtis, Founding Partner WaterSeer in a press release. The company says it will deploy 100 devices to some of its distributors first in California and Texas and then throughout the United States, and in different parts of the world; Colombia; Mexico, Peru, South Africa, Tanzania; Botswana, and Mozambique.