Posters
Come meet the poster presenters to ask them questions and discuss their work
We would like to invite you to come and see the posters at our upcoming conference. The posters will showcase a diverse range of research topics, and will give delegates an opportunity to engage with the authors and learn more about their work. Whether you are a seasoned researcher or simply curious about the latest developments in your field, we believe that the posters will offer something of interest to everyone. So please join us at the conference and take advantage of this opportunity to learn and engage with your peers in industry and the academic community.
PO158: Site-specific design optimization of semisubmersible platforms for floating wind turbines
Stefano Bontumasi, R&D Project Manager, Eni SpA
Abstract
Floating offshore wind turbines are key technologies to harness the abundant wind resource in sea areas characterized by water depths where bottom-fixed structures are unfeasible. In this context, this work addresses the topic of techno-economic optimization of floaters and mooring systems, a key challenge in the strive to lower the high cost of energy connected to this technology. However, reducing the cost of energy for such system remains a complex challenge, as floating wind energy platforms comprise multiple components subject to a range of technical issues, including aerodynamic, hydrodynamic and structural complexities. In this study, we implemented a multi-stage optimization framework employing numerical methods across different levels of model fidelity: frequency-domain analyses, Finite Element Analyses (FEA), time domain analyses, and the characterization of key hydrodynamic parameters leveraging a CFD-based simulation tool. The design optimization process involves multiple variables of the substructures including dynamic performance, power production and capital costs; selection of the final candidate is then performed according to a CAPEX-over-productivity parameter. The optimization workflow is applied to two floaters for the IEA 15 MW reference wind turbine: a four-column semisubmersible, with a centered wind turbine, and a three-column semisubmersible, with an eccentric wind turbine. The semisubmersible concepts are optimized on two different deployment sites, one in the Mediterranean Sea, the other in the Northern Sea, characterized by far different wind resource availability and wave conditions. The optimization process begins with a thorough assessment of site conditions, like water depth, wind resource availability, wave characteristics and soil properties. Specific load cases are developed for each location as per DNV standards, addressing both power production and ultimate load scenarios. The optimized platforms are described in terms of masses, dimensions, dynamic performance, power production and capital costs. No major differences in productivity, cost and performance are found among the two concepts.
