Dew harvesting (Green Prophet)

Read at :

http://www.greenprophet.com/2009/06/tal-ya-water-dew-irrigation/

Tal Ya Water Irrigation Trays Make the Most of Dew

Karin Kloosterman

The ancient Israelites used stones to collect dew from the air, now the modern ones are taking the idea further.

A new Israeli company Tal-Ya Water Technologies, which launched in May, promises to squeeze dew from the air for watering crops where water resources are precious or scarce. This new invention has a number of ecological benefits that go beyond simple water savings.

For about $1 a piece, per plant, a square serrated tray made from a special plastic composite sits directly on the ground.

The reusable tray is fitted with a hole in the center for a plant to grow. Using non-PET recycled and recyclable plastic with UV filters, and a limestone additive, Tal-Ya’s trays do not degrade in the sun or after the application of pesticides or fertilizers.

An aluminium additive helps the trays — about 70 cm by 70 cm for a pepper plant — respond to shifts in temperature between night and day. When a change of 12 degrees centigrade occurs, dew forms on both surfaces of the Tal Ya tray, which funnels the dew and condensation straight to the plant and its roots.

The trays are also made in larger sizes for trees, Avraham Tamir, the company head and inventor tells ISRAEL21c.

Weeds out weeds, uses less water and fertilizer

“Using our system has a number of benefits,” Tamir says. Farmers don’t need to worry about weeds because the trays block the sun, so weeds can’t take root. “Farmers need to use much less water, and in turn much less fertilizer on the crop,” he explains. Less fertilizers and pesticides means less groundwater contamination.

Locking together like pieces of LEGO, special sections of the tray make space for irrigation and watering equipment to fit into the solution.

Field tests in Israel with the Ministry of Agriculture suggests whopping water savings of up to 50 percent of irrigated water by using the Tal-Ya system.

“Dew collection starts at night,” Tamir says. “The critical mass goes down below,” he explains while pointing to the serrated edges of the trays. If it rains, we can amplify 1 mm of rain so that it equals 27 mm.”

Protection from extreme temperature change

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Author: Willem Van Cotthem

Honorary Professor of Botany, University of Ghent (Belgium). Scientific Consultant for Desertification and Sustainable Development.