High performance under extreme conditions

The WindFloat® is a structurally efficient, three-column semi-submersible floating platform for wind turbines that combines a unique set of features to provide unparalleled performance in the harshest environments.

The smart hull trim system adapts to metocean conditions by shifting water ballast between columns to keep the wind turbine tower at vertical, maximizing output and minimizing loads.

Designed for performance

The WindFloat® achieves stability via a combination of waterplane area (footprint), draft, and column diameter. The three-column design is scalable to accommodate the largest offshore wind turbines, efficiently managing loads with a minimum increase in structural mass. 

The WindFloat® has a shallow draft structure that allows turbine installation at most ports, without the need for temporary buoyancy or single-use permanent buoyancy systems, removing the need for offshore heavy lifting, and is inherently stable during transit. Permanent water ballast is used to lower the platform to its target operational draft for additional stability. The smart hull trim system moves water from column to column to compensate for mean turbine thrust loads during operation, boosting performance and power yield.

WindFloat Atlantic in operation during storm Dora, December 2020. Significant wave height up to 9 m.

WindFloat Atlantic in operation during storm Dora, December 2020. Significant wave height up to 9 m.

Damping plates: dynamic stability

The WindFloat® patented damping plates fitted at the bottom of each column minimize wave and turbine induced motion, enabling the platform to stay light while performing as if it was a much larger structure (hydrodynamic added mass).

Passive ballast: flexible draft and added stability

The WindFloat® has ballast tanks located at the bottom of each column, allowing the draft of the platform to be adjusted between temporary and operational phases, providing the flexibility to install and commission wind turbines at most ports prior to towing the complete system to site. Once at sea, these tanks are filled with seawater to achieve platform operational draft, lowering the overall center of gravity and further increasing stability.

Smart hull trim system: increased power production

The WindFloat® patented smart hull trim system consists of a robust and fully redundant ballast system that moves water from column to column to compensate for changes in average wind velocity and direction to keep the tower’s mean pitch angle at zero degrees. Compared to fully passive semi-submersibles, the WindFloat® optimizes power production and reduces structural loads during operation. 

The system is entirely closed-loop, meaning no water is exchanged between the platform and the environment.

The smart hull trim system is highly efficient and, unlike fully passive floating platform designs, allows the WindFloat® to adapt to learn from its environment, boosting revenue generation over the course of the 25+ year project lifetime.

Wind turbine agnostic

The WindFloat® is designed to host any conventional commercial wind turbine with only software modifications and a site-specific tower. This flexibility allows developers to choose the best turbine for the project, balancing cost and performance.

Flexible scaling

The WindFloat® scales flexibly to accommodate increasingly larger wind turbines with minimal additional steel mass while maintaining simplicity during operations and installation.

Scaling the WindFloat® from the 2 MW turbine installed on the WindFloat 1 prototype to the nearly 10 MW turbines installed at KOWL showed that a 5x increase in turbine size could be met with less than a 2x increase in platform weight. Studies with next-generation wind turbines, with capacities in the 15 to 20 MW range, show that these scaling efficiencies continue to be a major benefit of the WindFloat®.

The wind turbine and floating platform form a highly coupled system that must be designed collaboratively to achieve optimal performance with minimal impact on the floating platform. Principle Power has class-leading experience in this space and works closely with all major wind turbine manufacturers and classification societies to assure designs meet site-specific customer requirements.

Let's get your project floating

Contact our expert team to learn about how we can support your floating wind project.