In order to fulfill the increasing demands for alternative energy, many offshore wind parks are planned in the North Sea, Baltic Sea and Irish sea. Aggravated conditions such as large water depths, increasing heights of towers and hubs, as well as other environmental conditions require new solutions for stability and service life of offshore wind energy converters. Therefore, the German Forschungsvereinigung Stahlanwendung e.V. has sponsored a research project. The aim of this project was to evaluate the individual problems concerning stability and service life of such structures and develop new solutions. This includes choice of steel grade, the technique for joining components, in particular the problems pertaining to cylindrical and conical connections, the assessment of the remaining life, methods to extend the service life and considerations on corrosion problems.
The advancement of regenerative energies causes a boom in the wind energy industry. In order to fulfill the increasing demands for alternative energy, and since a larger amount of space is available and the wind conditions are more constant offshore than onshore, many offshore wind parks are planned in the North Sea, Baltic Sea and Irish Sea. Aggravated conditions such as large water depths, increasing heights of towers and hubs, as well as other environmental conditions exist here, however. At the ISOPE-Conference 2006 in San Francisco, a new research project concerning solutions of details regarding fatigue and the use of high-strength steels for towers of offshore wind energy converters was introduced (Puthli et al., 2006). The investigations are completed now and the most important conclusions will be presented. The aim of this project was to evaluate the individual problems regarding stability and service life of such structures and to develop new solutions. This includes the choice of steel grades, the technique for joining components, in particular the problems pertaining to cylindrical and conical connections, the assessment of the remaining life and considerations on corrosion problems.