Most of the offshore wind developments to date, globally, have been bottom-fixed foundations located in shallow waters (<30m water depth) and in close proximity to shore. However, as technology improves and as space for near-shore sites decreases, offshore wind development is projected to trend towards deeper waters. Floating wind is thus expected to become one of the leading renewable energy sources over the next decade or so. Notably, the success of pilot projects in Europe has confirmed the viability of floating wind technology, drawing in additional developers to the market. In the United States, there is a significant potential for floating offshore wind off the coast of California, Maine, and Hawaii. While the majority of current floating wind activity is concentrated in <200m water depth, further technology improvement coupled with experience from floating oil and gas developments will lead to even deeper floating wind projects in the future.
One key aspect for floating wind technology is the floater foundation that will support the wind turbine assembly. The entire unit will be moored to the seabed and be subject to challenging environment conditions throughout its service life (akin to a floating oil and gas production facility). There are several floating wind concepts currently in the market - a handful are field-proven at pilot project scale but the majority are still in development phase, each with their own unique offering. The purpose of this paper is to perform an independent qualitative assessment of the current floating wind concepts. The assessment will focus on aspects related to technology readiness, design complexity and scalability, material selection, constructability, installation, operations, and maintenance. This paper provides the offshore wind industry with an unbiased opinion on available designs as well as an insight into perceived challenges for future developments. As a disclaimer, it is noted that Wood has utilized public-domain information for this study and has no preference towards any existing floating wind concepts or designs.