The CADEMO project will feature the world’s most powerful wind turbines atop the largest floating platforms proposed to date.

Floating Wind Turbine Technology

Offshore wind has become a key cornerstone of global efforts to decarbonize electricity production. However, efforts to date worldwide have been restricted to areas with relatively shallow water depths (less than 50 meters), with turbines secured to the seabed using large deep-drilled piled foundations. A floating wind turbine is an offshore wind turbine mounted on a floating structure, offering a more flexible solution, easing spatial constraints as it is not limited by seabed depth or conditions.

Floating platforms are an ideal fit for California, where a combination of high wind speeds and near-shore deep water offers an opportunity to demonstrate new floating offshore wind technology at a lower cost than can be achieved elsewhere. In leveraging the existing offshore engineering capability in the California supply chain, CADEMO will create a unique opportunity to establish the region as a world center for the floating offshore wind industry.

CADEMO will use the latest offshore wind turbine technology. The turbines will be visually similar to conventional onshore wind turbines, but they will be taller and with larger blades to produce high generation capacities. Each turbine will be capable of generating 12-15 megawatts (MW) of electricity for a maximum project capacity of up to 60 MW – a deployment that has not yet been made at this scale anywhere in the world.

Floating Platforms

As part of its technology demonstration strategy, CADEMO is a technology-agnostic project, seeking to evaluate different floating platform designs and deploy technology suitable for the site conditions. Two suppliers have been short-listed in the early assessment:  SBM Offshore and Saitec. However, the project will finalize its technology assessment process soon, possibly modifying the early choices made. It is fundamentally important that the project deploys technologies that are suitable for the Outer Continental Shelf area and can provide a robust and executable project.

SBM Offshore’s Tension-Leg Platform.

The SBM Offshore floating platform is a lightweight steel-based tension leg platform (TLP).  Most of the structure is submerged underwater and is anchored to the seabed under tension by near-vertical cables to minimize movement. Currently, three units of 8.3 MW each are being completed for the Province Grand Large project in France, to be installed 2023.

SBM Offshore

Saitec’s SATH Floating Barge.

The SATH (Swing Around Twin Hull) floating platform is a prestressed concrete floating platform consisting of two cylindrical, horizontal hulls with conical edges linked to each through bar-frame structures.

The design uses a single point mooring system (currently used in oil and gas applications) in which the platform weather-vanes into the facing wind, anchored to the seabed by catenary cables.

The system has been extensively modeled in tank testing campaigns and validated through numerical models, and is being demonstrated in two prototype deployments in open seas off the northern coast of Spain.

Saitec Offshore