World Wind Watch | Green Energy News

September 21, 2003 – Vol.8 No.26

WORLD WIND WATCH.

Wind turbines continue to improve with each new generation - greater output capacity and the ability to capture ever lighter breezes. And the improvements are easy to comprehend. Increasing the length of rotor blades allows more surface area for wind to come in contact with and push against. The longer rotors too, acting like lever arms, allow light breezes to turn the generator to more easily to produce a flow of electric current. (Like moving a big rock the longer the stick, pole or pry bar the less effort is required to move it out of the way.) Further, when rotors are made of lighter materials - weigh less, a lower mass - less effort, less wind is needed to turn them.

In its newest models of turbines - the V-90 series - Vestas has incorporated these improvements and others. The line of 1.8, 2.0 and 3.0 megawatt turbines to begin serial production in 2004 has rotors up to 44 meters long (exceeding Vestas’ current maximum of 39 meters) that are made of light-weight carbon fiber composites as opposed to glass fiber rotors now used. The light weight of the new rotor and a new aerodynamic profile also reduces the wear and tear on the turbine shaft and its bearings.

In the nacelle too - which holds the electric generating equipment - Vestas has made upgrades such as removing the conventional main shaft to significantly reduce the nacelle’s weight thus lowering transportation and installation costs. Visit Vestas at http://www.vestas.com.

REpower will begin to upgrade its line of megawatt class turbines by building a 5-megawatt prototype in 2004. What could be the largest turbine in the world, the prototype will have a rotor diameter of 415 feet (126 .5 meters) with a hub height of 394 feet (120 meters)

The REpower prototype will be tested on land, but its intended use will be for offshore installations. Visit REpower at http://www.repower.de/ .