Acciona's new low-wind turbines
Spanish turbine manufacturer Acciona Windpower is adding a low-wind rotor to its three-megawatt platform for low wind sites. Before the end of the year, the Spaniards want to build a prototype of the AW 125/3000.
Compared to the current largest model, the AW 116/3000, with its low-wind, 125-meter rotor diameter, enlarges the swept area by around 16 percent. The company promises that the fourth evolution of the three-megawatt platform produces a turbine that delivers maximum energy production at a low cost for almost any wind site.
Acciona tailor-made the AW 125/3000’s swept area of 12,271 square meters for the average wind speeds of low-wind sites.All over Europe, sites with an average wind speed of 7.5 meters per second throughout the year will be standardized to the IEC III class. At these speeds, the energy content of the wind is 258 watts per square meter (at an air density of 1,225 kg/m³).
A three-megawatt generator is calculated to sufficiently reach full power at 244 watts per square meter rotor area, due to long blades. In practice, however, a maximum of 52 percent of the wind energy can technically be used. In order to increase the yield in sites with less wind, the new turbine will be constructed on concrete towers as tall as 120 meters.
Fundamental changes were not necessary in turbine construction — Acciona adapted turbine construction of the three-megawatt platform, so that the turbine will now be available with rotor diameters of 110, 109, 116, and 125 meters. The platform strategy allows the turbines to be optimized for a variety of sites with as few changes to the basic concept as possible. All the major turbine manufacturers currently employ this strategy.
In early 2014, after the AW 125/300 is certified, the commercial delivery of versions with 50 and 60 hertz is expected to start. (Denny Gille / Marisa Irwin / Craig Morris)