The importance of Renewable Energy is usally broadly accepted within the population. The progress of introduction and improvement within certain regions and states however is strongly depending on the political and legal background. Also in Hungary the importance of wind energy as a significant part of potential future energy resources is generally accepted. To start a wind energy project should therefore be a rather easy task. But when it comes to the details of the financial calculations and the necessary permissions from the authorities a completely different picture of the situation is perceived. A special aspect of cost calculation in wind energy is the fee which has to be paid for the forecast errors of the energy delivery. This book is trying to give you some background of the legal and economical questions related to wind energy forecast and fee calculation by using actual data of the Hungarian Meteorological Service and the technical data of an existing wind project. It was the intention of the author to generate a practicle guide into this topic by combining technical, legal and commercial details with a general introduction of the background.