Composite offshore floating platforms

To meet the requirements for Net-zero 2030, particular attention is given to renewable energies. Among these, offshore wind is a technology still under development and studied with particular focus due to its greater wind predictability, reduced oscillation in the day-night cycle, and extensive experience in the onshore wind energy sector. Additional advantages are present in floating solutions, which can be installed in sites with depths greater than 30 meters, where generally stronger and more consistent winds are found, essential parameters for improving turbine performance.

The analysis focuses on ReFloat, a toroidal platform made of GFRP, a material with a good strength-to-weight ratio, with good resistance to marine corrosion and fatigue due to wave motion. Additionally, the development of a system for energy production and storage located inside the toroid is studied, able to supply potential users in the maritime sector. The study addresses both the design part of the platform, to meet technical requirements, and an economic study to compare the construction of the platformwith a classic one made of steel and concrete. Finally, the production of a single 15MWwind turbine is simulated in different sites to verify the effectiveness of the off-grid system and to quantify the hydrogen supply developed by single platforms. It is found that, depending on the traffic in the zone, for small and medium-sized vessels, it is possible to use FOWT independently or with the development of small wind farms, while for large vessels, e.g. cargo ships, the development of large wind farms is necessary tomeet the demand of individual vessels.