A new generation of machines sucks the moisture from air to provide clean drinking water. And they use relatively little energy to do so.
The summer of 2009 was the hottest ever recorded in parts of Texas and the accompanying drought has prompted authorities in many areas to order residents to reduce their water use. The average temperature of 88.6 degrees in August was almost 2 degrees hotter than the previous high in 1925, according to the National Weather Service.Meanwhile the drought in California is in its third year and even sub-tropical Florida is having a bit of a dry spell. Officials are warning that alternative sources of water need to be found soon if more severe restrictions are to be avoided.
But perhaps what they are looking for is not just under their noses, it is in their noses. It has been estimated that the atmosphere, the air that we breath, contains 3.1 quadrillion (10 to the 15) gallons or 0.04% of the world’s total supply of fresh water. Not only is it abundant, it there for the taking and surprisingly easy to extract.
In fact man has used simple atmospheric water generators for centuries if not millennia. All that is needed are warm days, cool nights and a surface for water to condense on. It’s what happens when dew forms on a metal roof.
You could create your own AWG in a matter of hours by building a framework to support a sheet of corrugated iron, seven to ten feet in the air. It should be inclined at 30 degrees to the ground, have a gutter to catch the precious precipitation and it works more efficiently if the under side of the metal sheet is insulated.
Alternatively you could buy one of the many rather more effective commercial AWGs currently in the market place. They are basically super dehumidifiers. But hook them up to a solar panel or a wind turbine and voila, you effectively have a well producing absolutely pure water, in the corner of your kitchen.
The EcoloBlue 28 Atmospheric Water Generator (http://www.ecoloblue.com/en/home-office) for instance produces up to 7 gallons or (28 litres) of pure drinking water per day. The precise amount depends on air temperature and humdity. (Water generators are ineffective at humidity of less then 35%.) It costs $1350 and the manufacturers claim that each gallon uses on average, $0.20 cents of electricity to produce. That’s about a fifth of the cost of a water delivery service. Of course that doesn’t include the filters you need to ensure your water is pure and they can cost a further $100 dollars a year.
Meanwhile the DewPointe Atmospheric Generator is listed at $2,000 but expect to pay closer to $1600. It claims a maximum output of 8 gallons, slightly greater than the Ecoloblue but again, it all depends on the prevailing heat and humidity. Power Consumption is 0.5 KWh. The Dewpointe places great emphasis on water purity, employing a 10-stage filtration process to ensure that the water is dirt free and UV filters to ensure it is contains no microorganisms.
That’s all well and good if drinking water is all you want. The average two person household uses roughly 23 gallons of water per day, so if you need to generate all your water, you need a larger machine.
Obviously they cost more, but one benefit is that the cost per gallon drops. The Ecoloblue 200, so-called because it produces around 200 litres per day, weighs in at around 320pounds and costs $11750. It consumes 0.5KWh of electricity per litre of water which, according to the Ecoloblue marketing director Traci Mondella, means that over the fifteen year life time of the machine, you’ll get water for just 1.4 cents per litre. If you power it by alternative means, which is more feasible with a larger device, the cost drops to near zero.
In truth AWGs are not yet a wise choice on economic grounds alone. Payback takes around five years-or more, depending upon how much water you use and how much water your local atmosphere can produce. But a couple of hundred dollars a year seems a small price to pay for complete autonomy.
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