Creating Drinking Water from Air

Cross-posted on Reuters

According to U.S. Government estimates, at least 36 states will face water shortages in the next five years, as available supplies decrease due to drought, rising temperatures, population and inefficient management.

Tensions created by mandatory conservation restrictions have turned neighbors against each other by reporting to the water police suspected illegal watering based on a lawn that was simply too green.

However, there is some good environmental news. Companies and individuals have developed technologies to capture water vapors in our air to create drinking water or to capture and collect dew.

These water makers may not end the severe water shortage, but they can
decrease the demand on our shrinking potable water supplies by providing useful conservation measures for drought-ridden communities. Water makers are providing drinking water to some of our troops in Iraq and have the capability to provide entire small villages with potable water when natural supplies are nonexistent or polluted.

Water makers are not a new technology. Fans of George Lucas's Star Wars may remember the home planet for the Skywalker family and Ben Kenobi was Tatooine, where the poor inhabitants were mostly moisture farmers who harvested water vapor from the atmosphere rather than growing crops by using a moisture vaporator. The harvested water was then used to recharge groundwater basins and reservoirs.

Back on planet Earth, it was theorized that the ancient Crimean city of Feodosiya [founded as Theodosia by Ionian Greek colonists from Miletus in the 6th Century BCE] used an air well constructed of stacks of stones as condensers and terra cotta pipes connected to wells and fountains to supply the city with water.

In the early 1900's,
rock air wells shaped similar to a bell with lots of "windows" were constructed to capture atmospheric humidity. The theory was that the air would be chilled by the rows of slates inside, deposit its moisture on the slates, and then the moisture would trickle from the slates to a collecting basin at the bottom of the well.

Many other water maker ventures were tried over the years with varying degrees of success. One interesting example is the use of
underground tunnels constructed to collect humidity in desert areas, such as Afghanistan, which are now used to evade US troops:
In the Sahara Desert there exist many miles of ancient underground passages called "foggaras" that have been dug into the sides of mountains. The tunnels connect with the surface through an air vent every 75 feet or so, serving to collect humidity and seepage. Similar excavations exist in Afghanistan, and have served to hide the movement of troops from observation by Soviets and Americans.
Today, companies are creating water makers that convert air into drinking water, sometimes with technology similar to a dehumidifier. The Aquamaker captures humidity in the air and transforms it into drinking water, complete with filters to eliminate pollutants in the air. The humidity levels affect how much water will be created.

"To make a sufficient quantity of potable drinking water, an air humidity level of at least 60% is preferred, although water can be produced in even dry desert air."

Water makers can be used to ease the water crisis as well as provide water supplies to communities that lack water due to physical or economic scarcity. Water makers can assist small villages where
drought or pollution has wiped out potable supplies. This is extremely important as "a child dies every eight seconds – worldwide, due to lack of clean drinkable water." Entire villages may be supplied with potable water:
Aquamaker's machines are capable of producing up to 5,000 liters of water at a time, which would be enough to supply an entire village with fresh water, without draining an area's precious natural resources. When used in combination with a solar power generator, they provide an environmentally friendly alternative to bottled water for areas with a limited tap water supply.
While some Aquamaker machines have a 5,000 liter capacity, another model is the same size as traditional office water coolers. Environmental benefits include eliminating the plastic water bottles that supply office coolers as well as decreasing trip traffic of transport trucks for water coolers. This model will produce 36 liters of water for "about 8 cents worth of electricity." At a retail price of $1,200 and daily operation costs of $15, tap water may seem cheaper…if water conservation is not needed in your area. Aquamaker is also planning a "countertop model for home use." This would be beneficial for areas whose hard water is so distasteful that people then buy bottled water, and may eliminate concerns about the pharmaceuticals which may contaminate our drinking water supplies.

One good sign is that governments are interested in the water makers. An Aquamaker official claims that in "five to ten years from now, we will be part of how Israel supplies its citizens with water." Presently, the Israel Defense Ministry has a number of the water machines being used throughout Israel.

Another water maker has caught the eye of environmentalist Willie Nelson, who has
cancelled his bottled water line business, dumping the plastic bottles for a new business venture with Wataire in Willie Nelson's Water From Air. The Wataire atmospheric water generator uses the dehumidifier technology to produce 6 gallons of water a day in an area like Miami that has an average 73% humidity and 76-degree temperature.

The Wataire has a home/office model that is a sink mounted filtration unit which processes the tap water. Additional models include counter top, commercial and industrial. The cooler model unit sells for
$1,499. Wataire is focused on specific uses of its air maker, including households, towns and villages, non-governmental organizations, humanitarian assistance organizations, disaster relief, food manufacturers, mining and petroleum exploration camps, offshore drilling platforms, military, and bottled water and beverage manufacturers.

The potential uses of water makers are numerous. Wataire provided water for two weeks to
drought areas in Georgia and Louisiana. The Wataire water maker was also used to provide water to the crew of the "Mars Society’s 4-month simulated Mars mission in Canada’s high Arctic." The confined quarters for the crew generated the high levels of humidity needed for the water maker. The water-producing greenhouse (graphic at link) is an interesting Wataire project:
Several exhaust fans force air through a greenhouse. Humid air passes through a series of cooling coils producing potable water. Natural coolant from saline groundwater is pumped to the surface. Energy to power the exhaust fans and lift the coolant can be from wind generators to provide a sustainable and environmentally-responsible water-producing system.

This system will provide drinking water for approx 30,000 people as well as supply an adequate supply of water to irrigate a greenhouse operation to supply a source of fresh vegetables to communities that currently are unable to produce enough for their needs. Wataire has identified the location for the first installation and is currently negotiating on the purchase of the property and seeking necessary permits to proceed with the project.
Another water maker is the Air Water Atmospheric Water Generator which is operated "similar to an air conditioner" using concepts from the natural processes of evaporation and condensation:
The air is sucked through the filter by the motor with the fan, that filter stops all living creatures – flies, mosquitoes, bugs and so on – and the water then enters a chamber where it is kind of squeezed through a condenser. It literally, in layman’s terms, the water is squeezed out of the air. It dribbles through the condenser, which is powered by a compressor, which of course, like the back of a refrigerator produces cold gas. It then goes down into the tank, which has got some copper pipes in there that keep the water at a very low temperature, and from there when you suck the water out and the actual filtration and the purification is done on a need-to-drink basis.
The machines can be operated using solar energy or electricity for the cost of less than 3 cents a liter. The water generators can produce 20 to 50,000 liters of water. The company has a range of models available, including a mobile unit which makes 1,000 liters of water and stores 850 liters; a unit that provides both water and icemaker; a commercial unit; a unit for small factories, clinics or hospitals which "delivers water continually as needed"; a lifesaver unit which "can sustain 5 liters of water for 100 people daily"; a villager unit which provides 1,000 liters of water daily for a small village and the irrigator unit for farming in under-developed countries.

Additional models are customized for particular industries or customer needs, such as the
oil industry, which has a model designed for use in offshore oil rigs or oil fields.

Coalition forces have been using the Air Water Atmospheric Water Generator in Iraq because it allows "troops to remain for much longer periods of time in remote parts of the desert." Aqua Sciences has developed water-harvesting technology that was "originally the brainchild of the Pentagon's Defense Advanced Research Projects Agency" that wanted a method designed to "ensure sustainable water supplies for U.S. combat troops deployed in arid regions like Iraq." Aqua Sciences now has contracts to provide water to our troops in Iraq and the next victims of a FEMA emergency disaster and is interested in global humanitarian relief services:

This atmospheric water generator is a 20-foot machine, which produces "600 gallons of water a day without using or producing toxic materials and byproducts." The Aqua Science water generator technology is not based on humidity, which enables it to operate in harsh climates.

The company does not discuss the details of its
technology, but has provided hints:
Aqua Sciences’ system uses a patented salty solution whose molecules attract and then pluck the water vapor atoms out of the air. Sher said his machine separates the new water from the briny mix, producing potable water.
(Wall Street Journal video at this link has interview with Aqua Science official who explains technology as well as operation.) Others have joined the search for making water. Two architect students working toward PhDs at a leading science and technology institute in Israel have created the "WatAir" as a "low-tech way to collect dew from the air and turn it into fresh water."

This invention won an international competition addressing how to provide potable water to millions globally.
The WatAir is an inverted pyramid of panels which collect dew from the air and transform the dew into fresh water in almost any climate. The idea originated from the natural process of leaves collecting dew. A 315 square-foot unit has the capacity to collect 48 liters of fresh water from the air per day. Quantification of the needed water supply would determine how many units are needed. As illustrated in the pictures at this link, the flexible panels collect the dew to one source:
Each WatAir unit features 96 square meters of lightweight dew-collecting panels that gravitationally funnel moisture from the air to one collective source. The designers estimate that each unit can collect roughly 48 liters of water in remote places or places that do not have any clean water sources. The panels are flexible, easy to collapse when not in use, and readily available to provide shade and even some shelter.
One of the inventors explained that the WatAir is designed to fit both rural and urban landscapes as well as provide other functions:
According to Cory, WatAir can be easily incorporated into both rural and urban landscapes because it has a relatively small base. Its vertical and diagonal design utilizes gravity to increase the collection areas. The panels are flexible and easy to collapse when not in use, and provide shelter from rain and heat and play areas for children.
While not a complete answer, water makers have been available for a few years with continued research and development to improve and expand capabilities. This is positive news of a promising technology to resolve issues we face with a global water crisis.

Guest contributor Patriot Daily is an environmental lawyer in California who blogs regularly at
Daily Kos on environmental, water, political and human rights issues.

Cross-posted on Daily Kos