Atmospheric water generator

AWG may require significant energy inputs, or operate passively, relying on natural temperature differences.

Biomimicry studies found that the Onymacris unguicularis beetle has the ability to perform this task.

These traditional methods were passive, employing no external energy source and relying on naturally occurring temperature variations.

[7][8][9] In 2022 brine-based extraction technology was contracted by the US Army and the US Navy from Terralab and the Federal Emergency Management Agency (FEMA).

[15] The rate of water production depends on the ambient temperature, humidity, the volume of air passing over the coil, and the machine's cooling capacity.

As a rule of thumb, cooling condensation AWGs do not work efficiently when the ambient temperature falls below 65 °F (18 °C) or the relative humidity drops below 30%.

Solid-state semiconductors are convenient for portable units, but this is offset by low efficiency and high power consumption.

The relatively cold (below the dewpoint) evaporator coil condenses water vapor from the processed air.

The most efficient and sustainable method is to use an adsorption refrigerator powered by solar thermal, which outperforms photovoltaic-powered systems.

In 2024 a sorption-based atmospheric water harvesting technology using a fin-array adsorption bed powered by high-density waste heat demonstrated 5.8 liters per kg of sorbent per day at 30% humidity via a 1 l adsorbent bed and commercial adsorbents.

The brine then enters a chamber, under a partial vacuum and is heated, releasing water vapor that is condensed and collected.

As the condensed water is removed from the system using gravity, it creates a vacuum which lowers the brine's boiling point.

[23] Hydrogels can capture moisture (e.g. at night in a desert) to cool solar panels[24] or produce fresh water.