[en] The author gives explanations and answers and comments data on issues related to wind energy. He discusses why this energy which is one of the oldest, emerges in the 21. century again, what is its share in electricity production and what it may become, how to compare KWh costs (wind and other sources), what are the other consequences of wind intermittence, whether wind energy is actually a promising way to reduce greenhouse gas emissions, where this energy is growing the fastest, what are the best wind sites, what is the potential of offshore wind facilities, what are the other limits of the wind energy development, whether wind energy has a different behaviour than other generators with respect to network disturbances, what are the selling condition, what is the role of the European Union in the development of solar energy in France