Monday, November 03, 2008

EWA squeezes drinking water from thin air


Karin Kloosterman
Israel 21c

For Dr. Etan Bar, CEO of EWA, it was a question of priorities. His company, which focuses both on solar energy and clean water extraction from the air, had already developed a new solar energy air conditioner that was sparking interest in the industry, but Bar realized that clean water was a far more pressing need. He put aside the air conditioner and began working on a new technology that could collect humidity naturally present in the air and turn it into clean water.

It sounds like a far-fetched idea, but it's actually thousands of years old. It was mentioned in the Bible and in ancient Jewish prayers, and archaeologists still find the stones Israelite farmers used thousands of years ago to collect dew for watering their crops.

The technology is the key

Essentially EWA (which stands for Extraction of Water from Air), has developed a clean technology that extracts water from the air, while using little energy in the process. The key is in its unique water adsorption technology - which employs a solid desiccant to trap the water - and a special energy saving condenser that reuses more than 85 percent of the energy input to the system.

Renewable energy sources, such as solar power, biofuel, waste heat or even the heat from organic matter are compatible with the system.

The company, which was founded in 2006, is based on nine years of research by Bar, a former researcher at Ben Gurion University. The company now has representatives in the US, India, Jordan, Cyprus, Australia and West Africa where EWA is helping farmers generate carbon credits, on top of providing them with clean water for drinking and irrigating their crops.

The technology, Bar tells ISRAEL21c, works in three steps: first is the absorption of air's humidity, then the removal of water from a solid desiccant (silica based gel granules) which holds the water, and third, condensation. The absorption of the humidity is an exothermic process (involving heat release), humidity absorption occurs spontaneously, and only minimal energy is used as the air is pumped through the unit. Heat recovery techniques are integrated as part of the condenser, reducing the cost for producing water to a reasonable price, similar to other processes, such as desalination.

Water is not created equal

Making use of renewable energy sources enables EWA to supply water at cheaper cost because the need for long distance piping and infrastructure (the water consumer is the water producer) is erased from the equation.

In countries like America and Canada where freshwater is abundant, people take long showers for granted. Today in less fortunate developing and even developed nations - such as Cyprus -- the cost of water is so high that even in 4-star hotels water to the shower taps is being turned off, Bar tells ISRAEL21c, after a recent experience on the Cypriot island. There a cubic meter of water costs 6 Euros, because it is transported all the way from Greece.

To compare - according to the US-based Global Policy Forum, the average American household consumes about 480 cubic meters (127 thousand gallons) of water during a year. While homeowners in Washington D.C. pay about $350 a year (72 cents per cubic meter), buying the same amount of water in the slums of Guatemala City would cost about $2,000.

More than a drop in the bucket

Even though clean water for drinking and bathing seems like a basic human right, for most of the worlds' poor it is a luxury. EWA hopes to change that: "One cubic kilometer of air contains 10 to 40 thousand tons of water -- enough to supply at least 100 thousand people with all their water needs, or enough 'safe' drinking water for two million," Bar explains. EWA's device, can be scaled up or down, and will produce anywhere from a few hundred liters of water per day to 1,000 cubic meters of water in a single plant.

The company, which employs 12, is currently operated out of Beersheba, Israel. Last year was the first year the company reported its earnings, at about $100,000, while this year, it predicts sales upwards of $5 million, and $100 million for 2009, mainly due to growing demand from Africa, India and Australia. The bottleneck right now is being able to supply demand, says Bar.

As global warming heats the world, and its population continues to grow, there is less water for everyone: "Due to the effectiveness at extremely wide ranges of environmental conditions and due to its low energy consumption, huge water plants could be built and operated using the novel EWA technology," says Bar. "The technology answers the world's desires for available, clean and safe water - without air pollution from energy production - and expensive infrastructure," he concludes.

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