Wind power plants from Siemens have evolved dramatically over the past 30 years. The first commercial wind turbine had a capacity of 30 kW and 5 meter long rotor blades, for a 10 meter rotor diameter. The latest turbine generation from Siemens has a six megawatt capacity and 75 meter long rotor blades for a rotor diameter of 154 meters – the largest in the world. Thus, the energy capture area and the turbine capacity have grown by a factor of 200 in the last 30 years.