Concept Design of Steel Bottom Founded Support Structures for Offshore Wind Turbines

Abstract

To meet growing energy demands wind energy has become an important source of energy. In the last decade wind turbines have been installed offshore to accommodate even more wind power. The offshore wind resource is of a better quality, resulting in higher electricity output. On the other hand, the costs of constructing and installing support structures for these turbines offshore is higher than onshore. Therefore offshore turbines are being made larger to economize in the support structure and installation costs. As the technology for wind turbines improves, the industry has developed wind turbines with rotor diameters as large as 150 m and power ratings of 8.0 MW. It is the intention to build wind farms in water depths of even 60 meters. The combination of increasing water depths, increasing wind tower heights and rotor blade diameters creates loads that complicate the foundation design. All of these factors pose significant challenges in the design and construction of wind turbine support structures and foundations.