High in the Himalayas in northern India, at a remote village near Phyang Monastery in Ladakh, stands two gigantic ice cones. They were built last winter by piping water from glaciers and streams high up in the mountains, and allowing the water to freeze in the cold winter nights. All throughout spring, the sun slowly melted the cones providing a steady supply of water for the villagers to irrigate their fields of barley, apples, and other crops. These ice cones are called ice stupas, because of their distinct shape resembling the mound-like Buddhist shrine. If everything goes as planned, there will be fifty more of these ice stupas everywhere in Ladakh providing farmers with tens of millions of liters of water to irrigate their crops with it.
The Ladakh region in in India is a cold desert. Being located on the leeward side of the Himalayas, monsoon clouds are denied entry leading to a dry and rainless climate. The main source of water here is the winter snowfall on the mountains.
Each winter large shelves of ice form at high altitudes and melt throughout the spring, flowing downwards as streams around which civilization thrive on the mountain. But during the two crucial months of April and May, when farmers plant new crops, the streams dry up. By mid-June, as temperature rise sharply, fast melting of the snow and glaciers in the mountains causes an excess of water and even flash flooding at times. By autumn, all farming activities ceases and yet, a small stream continue to flow throughout the winter steadily and wastefully going into the Indus river without being of use to anybody. Photo credit: Sonam Wangchuk
In 2014, a Ladakhi engineer, innovator and education reformist Sonam Wangchuk, came up with a solution to the problem—collect the wasting winter water from the streams and store it in giant ice mountains that melt in spring and feed the farms when water is most needed.
The idea grew in his mind one warm May morning when Wangchuk noticed ice under a bridge, which made him realize that it was direct sunlight that was melting the ice on the ground and not ambient temperature.
Wangchuk’s solution is very simple and elegant that requires no pumps or power to work. An underground pipe brings water from high up the mountains, usually 60 meters or more, to lower altitude where it is allowed to spray out into the freezing winter air by the pressure of gravity alone. The water instantly freezes before it falls to the ground, slowly forming a huge ice cone roughly 30 to 50 meters tall. The cone shape also has the advantage of having a low surface area in comparison to its volume, exposing very little of the ice to direct sunlight, and thus delaying its melting.
One of the first prototypes Wangchuk built was 20 feet tall and contained 150,000 liters of water. It lasted throughout the spring and into mid-May even when the temperature was above 20°C. Another much larger stupa grown near a forest survived until July.
The two ice stupas Wangchuck built near Phyang Monastery are about 80 feet tall and contained enough water to irrigate 10 hectares of land throughout the dry months. It was entirely a crowdfunded project. For his work, Wangchuck also received financial assistance from the Swiss watch giant Rolex. The money, he says, will be used to build more ice towers.
Source…..Kaushik in http://www.amusingplanet.com