Sustainable Marine Structures

Design Basis Considerations for the Design of Floating Offshore Wind Turbines

Ove Tobias Gudmestad

Department of Marine Science, Western Norway University of Applied Science, Haugesund, 5528, Norway; Department of Mechanical and Structural Engineering and Material Science, University of Stavanger, Stavanger,4021, Norway

Anja Schnepf

CoreMarine AS, Stavanger, 4014, Norway

DOI: https://doi.org/10.36956/sms.v5i2.913

Received: 30 July 2023; Revised: 25 August 2023; Accepted: 5 September 2023; Published:16 September 2023

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Abstract

The wind farm owner/operator must prepare a Design Basis to facilitate the design of floating offshore wind turbines. The Design Basis is crucial to ensure that the individual elements of the wind farm are designed according to the relevant standards and the actual site conditions. In case of under-design, systematic failures can occur across the wind turbines, which can result in progressive damage to the turbines of the wind farm. This paper focuses on the safety and overall economics, including limiting potential excessive costs of heavy maintenance caused by damage due to under-design. Thus, this paper highlights critical aspects of particular importance to be implemented in the Design Basis document. Meeting all required constraints for developing offshore wind farms in deep water may result in higher costs than initially anticipated. Nonetheless, a realistic cost estimation for all phases of the project, engineering, construction, transport, and installation on site, remains essential for all engineering projects, including those involving renewable energy.

Keywords: Design Basis, Safety level, Wave conditions, Current conditions, Soil conditions, Transformer stations, Insurance, Costs for wind turbine projects

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