The greenhouse effect with its negative impact, global warming, has to be limited by lowering greenhouse gas emissions. Therefore renewable energy sources are getting more and more important in order to ensure a sustainable energy mix. Wind energy production plays a major role among others like hydropower or solar power and the last assessment report of the United Nations mentions that renewable energy can provide 30 to 35 % of electricity by 2030. The key will be the development of new renewable energy sources and the continuous enhancement of economic production methods for the established renewable energy sources like wind energy.