"Our project starts out as a desire, a whisper, like grasping at straws, clenching water. Taking clues from the way the wind caresses a field of wheat, or reeds in a marsh; our hair on a gusty afternoon."
Designed for Site #3 in Abu Dhabi, adjacent to Masdar City Site.
Concept and Design: Darío Núñez Ameni and Thomas Siegl, with Atelier dna
The Masdar Windstalk project consists of 1203 stalks, 55 meters high, anchored on the ground with concrete bases that range between 10 to 20 meters in diameter. The silent stalks are made of carbon fiber reinforced resin poles, 30 cm in diameter at the base and 5 cm at the top. The top 50 cm of the poles are lit up by an LED array that glows and dims depending on how much the poles are swaying in the wind. When there is no wind–when the poles are still–the lights go dark. The bases that support the poles are arrayed along the site following a logarithmic spiral, the kind we see in the center of a sunflower. The bases all touch each other, forming a kind of carpet, a kind of fabric.
The bases are shaped like vortices–no two vortices are identical. When it rains, the rain water slides down the slopes of the bases to collect in the spaces between, concentrating scarce water. Here, plants can grow wild. You can walk on the bases of the poles, you can traverse the whole site by walking from base to base. You can lean on the slopes, lie down, stay awhile and listen to the sound the wind makes as it rushes between the poles.
Within each hollow pole is a stack of piezoelectric ceramic discs. Between the ceramic disks are electrodes. Every other electrode is connected to each other by a cable that reaches from top to bottom of each pole. One cable connects the even electrodes, and another cable connects the odd ones. When the wind sways the poles, the stack of piezoelectric disks is forced into compression, thus generating a current through the electrodes.
Within each concrete base is a hollow chamber that houses a torque generator.
The generator converts the kinetic energy of the swaying poles into electrical energy by way of an array of current generating shock absorbers, which convert energy produced by the forced movement of fluid through the shock absorber cylinders. The electricity that the project generates isn’t constant, it depends on the wind. To compensate you need a kind of battery, a capacitor, a way to store energy: Below the field of poles are two very large chambers, chambers as large as the whole site. The chambers are shaped like the bases of the poles but inverted, then inverted again, and again and once more. There’s upper chamber and a lower one beneath. When the wind blows, part of the electricity generated powers a set of pumps, the pumps move water from the lower chamber to the upper one. When the air is still–when there is no wind– the water from the upper chamber flows down again turning the pumps into generators. The project is conceptual, yet It is based on a set system that already exists and works.
The shape of our Windstalks should be optimized to behave as chaotically as possible, they should flutter, oscillate, vibrate. Computer generated simulations can aid in determining and optimizing the best profile for maximizing movement and variation.
It is roughly estimated that the overall output of the project is comparable to that of a conventional wind turbine array. While a single wind turbine that is limited in height to 55 meters may produce more energy than one of the Windstalks, the Windstalks can be packed in denser arrays.
Entry for 'Land art generator' competition.
Second Prize Winner.
2010. Masdar U.A.E. www.landartgenerator.org