The use of wind turbines can be considered from various points of view. The use of the generated energy, the organisational integration into the public energy supply infrastructure, the operational concepts, and the geographic location all characterise the range of possible applications. The size of the turbines is of essential importance. The areas of application and use for small wind turbines with an output of a few tens of kilowatts are a priori different from those for large turbines in the megawatt output range.