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Posts Tagged ‘wind’

Small-scale wind farms

Posted in Research by Kate Archdeacon on December 1st, 2009

Source: Environmental Research Web

turbine1
Image via physicsworld

From “Fish inspire wind farm configuration”, Edwin Cartlidge

Conventional wind turbines work best when located as far as possible from the destructive vortices of neighbouring turbines. However, a pair of scientists in the US have worked out that the performance of other kinds of turbine actually improves when they are placed close to one another, concluding that wind farms could therefore be made much smaller than they are today.  The familiar propeller-like turbine with a horizontal axis of rotation can convert 50% or more of the energy from the wind that it is exposed to. In a wind farm, however, the wake from one turbine will disturb the air reaching the blades of its neighbours meaning that turbines must be placed far apart.

A less familiar family of turbines have a vertical axis of rotation.  Individually, these vertical-axis turbines are less efficient than the horizontal-axis devices because only part of the turbine can be pushed by the wind at any one time, and they have therefore proven far less popular. However, these turbines have a significant advantage over the horizontal-axis variety – their power output can be increased when they are placed very close to one another.  Now, Robert Whittlesey and John Dabiri of the California Institute of Technology have worked out how best to arrange such closely spaced turbines by drawing on the work of aeronautical engineer Daniel Weihs, who showed in the 1970s how fish save on energy by swimming within schools. Such fish form a series of offset rows, and Weihs found that fish get carried forward by the vortices created by the swimming motion of their two closest companions in the row immediately in front of them. Whittlesey and Dabiri wondered whether the relative spacing of vortices produced by an individual fish might serve as a good template for the arrangement of vertical-axis turbines within a wind farm and set up a computer model to test this idea.

Read the full article by Edwin Cartlidge.


Harvesting the wind – integrating existing energy structures with new

Posted in Models by fedwards on June 3rd, 2009

This article, Harvesting the wind, was originally published by Suzanne LaBarre on 13 May 209 on the Metropolis website. It demonstrates an innovative model to integrate existing powerlines with wind energy. An alternative version of distributed systems perhaps? The full article can be found here.

Harvesting the wind
From the window of a TGV hurtling through France, the countryside flattens to a smudge—electrical towers rise and recede in clusters, and tall, lanky wind turbines seem to whip off pirouettes like a young Moira Shearer. Most passengers turn their heads, nodding off on a neighbor or burying their noses in Le Monde, but for a tri­umvirate of young designers, the sight is a view of the future. The passing turbines and pylons augur a new way to harness renewable energy in a country that relies almost entirely on nuclear power. “When we’re riding on the train, we al-ways see pylons, and some turbines too,” Nic­ola Delon says. “We say, ‘Both are here. Can’t we mix them together?’”

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