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 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.
"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. "
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..