Advice Archives

Archive for the ‘Turbine Siting’ Category

Selecting a Wind Turbine Site

Posted on: April 15th, 2011

Wind Conditions Looking at nature itself is usually an excellent guide to finding a suitable wind turbine site. If there are trees and shrubs in the area, you may get a good clue about the prevailing wind direction. If you …]
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Park Effect

Posted on: November 3rd, 2008

As with the wake effect , each wind turbine will slow down the wind behind it as it pulls energy out of the wind and converts it to electricity. Ideally, we would therefore like to space turbines as far apart as …]
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Turbulence

Posted on: August 14th, 2008

You  have probably experienced how hailstorms or thunderstorms in particular, are associated with frequent gusts of wind which both change speed and direction. In areas with a very uneven terrain surface, and behind obstacles such as buildings there is similarly …]
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Tunnel Effect

Posted on: May 15th, 2008

If you take a walk between tall buildings, or in a narrow mountain pass, you will notice that the same effect is working: The air becomes compressed on the windy side of the buildings or mountains, and its speed increases …]
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Hill Effect

Posted on: May 11th, 2008

A common way of siting wind turbines is to place them on hills or ridges overlooking the surrounding landscape. In particular, it is always an advantage to have as wide a view as possible in the prevailing wind direction in …]
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Wind Speed Variability

Posted on: May 1st, 2008

The  wind speed is always fluctuating, and thus the energy content of the wind is always changing. Exactly how large the variation is depends both on the weather and on local surface conditions and obstacles. Energy output from a wind …]
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Obstacles

Posted on: April 11th, 2008

Obstacles to the wind such as buildings, trees, rock formations etc. can decrease wind speeds significantly, and they often create turbulence in their neighbourhood. The turbulence is more pronounced behind the obstacle than in front of it. Therefore, it is best to …]
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Roughness Class

Posted on: March 3rd, 2008

High above ground level, at a height of about 1 kilometre, the wind is hardly influenced by the surface of the earth at all. In the lower layers of the atmosphere, however, wind speeds are affected by the friction against …]
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Wake Effect

Posted on: January 13th, 2008

Since a wind turbine generates electricity from the energy in the wind, the wind leaving the turbine must have a lower energy content than the wind arriving in front of the turbine. This follows directly from the fact that energy can …]
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The Roughness Rose

Posted on: January 12th, 2008

If we have measured the wind speed exactly at hub height over a long period at the exact spot where a wind turbine will be standing we can make very exact predictions of energy production. Usually, however, we have to …]
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