http://www.treehugger.com/renewable-energy/worlds-longest-wind-turbine-rotor-blade-measures-246-feet.html Impressive beast! World's longest wind turbine rotor blade measures 246 feet! Michael Graham Richard (@Michael_GR) Energy / Renewable Energy July 30, 2012 © Siemens How Big Can They Get? A single of these giant wind turbine blades produced by German manufactuer Siemens is almost as big as the wingspan of an Airbus A380, the world's largest airliner. At 75 meters (246 feet), this massive beast is destined for a prototype 6-megawatt turbine to be erected at Denmark's Østerild test station. This arms' race in wind turbine size is due to the simple fact that as turbine blades get longer, the amount of electricity produced increases exponentially - it's all about the surface area covered by the rotor - and as more offshore projects are built, it makes more sense to build fewer big turbines than lots of small ones to control costs. © Siemens Siemens writes: "As it moves, each rotor covers 18,600 square meters, which is the size of two and a half soccer fields. The tips of the blades move at up to 80 meters per second, or 290 kilometers per hour. The huge rotor was made possible by special technologies that enable Siemens to make extremely strong yet lightweight structures. " This blade weights 20% less than conventionally produced blades thanks to those special lightweight materials. © Siemens "the entire blade is poured as a single piece made of glass fiber-reinforced epoxy resin and balsa wood. As a result, the blade has neither seams nor bonded joints and is extremely robust. The gigantic rotor, which measures 154 meters, has to withstand huge air masses, as it is hit by the energy of 200 tons of air per second when the wind blows at a speed of 10 meters per second. " © Siemens As you can see, transportation is starting to get difficult. Maybe at some point the manufacturing plants for large offshore turbines will need to be located right on the shore so that the turbine parts don't have to be transported by road or rail.. Via Siemens, GCC ======================== http://www.energy.siemens.com/us/en/renewable-energy/wind-power/wind-turbine-technology/blades.htm#content=Lightning%20protection%20system A IntegralBlade® technology Integral blade In 2000, we achieved our first major blade-technology advancement with the development of IntegralBlade® technology. Siemens remains the only wind turbine manufacturer to use blades cast in one piece in a closed process. IntegralBlade® technology eliminates glue joints to deliver blades of optimum quality, strength, and reliability. Aerodynamic optimization To further boost the efficiency of Siemens blades, we developed the Power Curve Upgrade package, which is designed to provide increased energy production. It includes the aerodynamic accessories DinoTail, DinoShell, and Vortex Generator. Used by Siemens Wind Power for more than a decade, these aerodynamic add-ons can also reduce noise emissions. B DinoTail DinoTails are serrated flaps that, true to their name, resemble the tail fin of a stegosaurus dinosaur. They are mounted at the airflow breakaway edge close to the blade tip, which accounts for most of the noise—and energy—produced by the blade. By decreasing turbulence on the trailing edge, DinoTails can enhance lifting performance while still keeping local acoustic emissions to a minimum. C DinoShell DinoShells, as applied on Siemens turbines, are fixed control surfaces attached from the blade shoulder toward the root. They effectively increase lift, especially on the root section of the blade closest to the hub. D Vortex Generator Our Vortex Generators are designed to improve the flow of air over wind turbine blades and thus enhance aerodynamic performance. They do this in the so-called boundary layer, the region of flow very close to the blade’s surface. E Shielding wind turbines against lightning Lightning protection system Our Siemens lightning protection system helps prevent failures caused by lightning strikes. All the main components of a turbine, including the nacelle, blades, controller, and tower, have extensive lightning protection integrated into their design. When a wind turbine suffers a lightning strike, whether onshore or offshore, the system provides the lightning with a safe path through the turbine and down into the electrical grounding. This safe path reduces the likelihood of damage to the main components. The blade is the highest point of the wind turbine and its most exposed component. For optimal blade protection, the lightning protection system is incorporated into the IntegralBlade® design, with receptors strategically placed on the blade surface. Our lightning protection system is subject to thorough testing as part of an ongoing program of optimization that continues to enhance our knowledge and experience of lightning protection at Siemens Wind Power. =============== http://en.wikipedia.org/wiki/Siemens_Wind_Power (Siemens history) Siemens Wind Power, (formerly Danregn Vindkraft A/S and Bonus Energy A/S) is a wind turbine manufacturer established in 1980 as Danregn Vindkraft. Bonus Energy was acquired by Siemens of Germany in 2004. The organisation became a separate division of Siemens in 2011, with headquarters established in Hamburg, Germany. In 2011, Siemens Wind Power had 6.3% share of the world wind turbine market.[2] In 2009 it had a market share of nearly 75% of European offshore wind turbines by capacity and number.[3] ================= http://www.gizmag.com/worlds-largest-wind-turbine-blades/23578/ ================= https://www.youtube.com/watch?v=uWVwG2_J0hc Dramatic video ================