The diploma thesis covers from the first examples of the use of windmills to modern high speed wind turbines. Over the last thirty years, globally installed wind power has been gradually increasing despite its higher cost, compared to other fossil energy sources. In the last decade, however, the cost of solar and wind energy has dropped drastically and has become the cheapest source of energy. As a result, the use of these resources is on the rise and will become increasingly popular in the future. The main purpose of this thesis is to provide a broader knowledge of one of the most promising renewable energy sources in the future and to acquaint readers with the current state of wind energy use globally. The first part of the diploma thesis presents the history of windmills. This is followed by the global use of wind energy. The properties of local and global winds are shown. The second part shows the basic laws of wind energy and the characteristics of turbines, such as types, components, connection to the transmission network and costs. At the end of thesis, there is an analysis of wind turbine efficiency depending on the height of the tower for the selected locations Nanos and Lisca.
The first analysis for the Nanos site showed that throughout the year, the wind turbine with the highest tower would achieve 7 % higher power compared to the wind turbine with the middle tower and 16,4 % higher power compared to the wind turbine with the lowest tower. The best month for this location was March, where almost all windmills reached an average power of 1 MW. The worst month for this chosen location was June, where the windmill with the lowest tower would fail to reach rated power throughout the month. The differences between individual tower heights and powers were even more apparent in the second analysis. A windmill with the highest tower would achieve 9 % higher power compared to the wind turbine with the middle tower and 22 % higher power compared to the windmill with the lowest tower. For this selected location, the best wind conditions were in February. The worst month for this chosen location was July. At the end of the analysis, a comparison between the two selected locations is shown. The results showed that windmills on Nanos would be exposed to better wind conditions and would reach rated powers of about 300 hours more compared to windmills installed on Lisca.
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