The CTC Technology Centre has developed an innovative digital twin approach for mooring systems in floating wind farms, capable of estimating mooring line tension in 0.15 seconds. This model offers a 99.95% reduction in prediction time compared to leading benchmark solutions and ensures the accuracy required for the operational monitoring of floating wind turbines. This innovation will enable virtually real-time analysis of mooring lines, making it easier to plan maintenance, prioritise inspections and anticipate potential problems.

The breakthrough, which forms part of the research carried out under the FUTCAN project, was unveiled at the 65th International Congress on Naval Architecture and Marine Engineering in Málaga. The forum, considered one of the major technical events on the European naval calendar, brought together 250 specialists and featured around 70 presentations and round-table discussions focusing on defence, decarbonisation, offshore wind, merchant shipping, fisheries, the blue economy and industrial transformation.

In this context, Marco Antonio Melgarejo, a data scientist at CTC, outlined the main features and advantages of a system capable of estimating stresses quickly and with low computational cost. The development is based on a data-driven Reduced Order Model (ROM). ROMs are a simplified approximation of a complex simulation model, which reduces the number of variables whilst preserving the essential accuracy of the system’s behaviour. In the solution presented by Melgarejo, estimates will be made using a finite element ROM trained with OrcaFlex, the internationally recognised software for this type of analysis.

As the CTC researcher explained, full simulation remains essential for the design and validation of mooring systems for floating wind turbines, but the ROM proposed in this solution provides the speed required for more operational management of these infrastructures.

In this regard, although this type of modelling began to be proposed around 2021, the approach presented at the Malaga forum proposes a model with improved accuracy, which maintains prediction times of less than one-sixth of a second.  In other words, it estimates stresses in less than 0.15 seconds, compared to the more than 5 minutes that a comparable high-fidelity dynamic simulation may require.  A virtually real-time estimate, enabling a shift from offline analysis to an approach much more closely aligned with the reality of each tension line.

By estimating stresses and, subsequently, the accumulated fatigue damage, the system allows maintenance to be planned according to the actual condition of the mooring. This will reduce preventive inspections at sea and optimise the use of resources such as vessels, equipment and personnel.

Now, having achieved very promising results, the aim is to demonstrate predictive capability against reference simulations and lay the foundations for its extension to fatigue analysis and remaining life assessment. An approach that demonstrates how a reduced AI-based model can become the core of a digital twin for a critical system such as the mooring of a floating wind platform.

Digital twin of mooring systems

Melgarejo’s approach is not an isolated development, but forms part of a clear strategy by CTC to define a complete digital twin of mooring systems. Indeed, this solution can be integrated with the Smart Sensor development of the MooringSense project, a European initiative led by CTC aimed at reducing operation and maintenance costs and improving the integrity management of mooring systems in floating wind farms. MooringSense set itself the objective of achieving a 10–15% reduction in the operating and maintenance costs of floating wind turbines, relying on monitoring, control and structural integrity technologies.

The data collected would feed into the model to be translated into estimated stresses and, subsequently, would enable the calculation of fatigue damage, which is the information that is truly useful for monitoring, inspection planning and predictive maintenance.

It should be noted that current monitoring technologies and methodologies for offshore mooring systems involve the use of robots, load cells and other systems whose cost is extraordinarily high. In this regard, the Smart Sensor developed in MooringSense can reduce the cost of the monitoring system itself by around 90% compared to other monitoring technologies.

With this work, CTC is not only presenting an advanced simulation tool, but a piece of technology with the real capacity to transform the management of mooring systems in floating wind farms: from real-time stress estimation to future integration into a complete digital twin, capable of anticipating fatigue, remaining life and maintenance requirements with an unprecedented level of detail.

A strategic sector for Spain

Offshore wind is a field in which Spain aims to establish itself through floating technology, structural manufacturing, industrial integration and coastal logistics chains. Solutions such as that proposed by CTC act as a catalyst for the development of floating wind power along the Spanish coast. The fact is that, despite its leadership in R&D&I linked to this type of energy, Spain is lagging behind in terms of commercial deployment in Europe.

The significance of this advance is not only technological, but also energy-related and strategic. Offshore wind power, included in Spain’s energy planning in line with the 2030 Agenda, is necessary to continue scaling up renewable energy and strengthening energy security. This aspect takes on particular importance given international uncertainty and geopolitical tensions in critical areas such as the Strait of Hormuz. The Roadmap for the Development of Offshore Wind and Marine Energy in Spain (approved in 2021 and aligned with the PNIEC 2023–2030) sets targets of 1–3 GW of floating wind power by 2030, contributing to 81% of renewable generation in the electricity mix and to the SDGs of the 2030 Agenda, such as climate action (SDG 13) and affordable and clean energy (SDG 7).