The volume and scale of opportunity for floating offshore wind (FLOW) is unprecedented - but comes with major challenges.
FLOW will need to provide industrialized solutions, (reliability, cost and production volume) - a huge challenge for un-proven technology's.
Floating offshore wind turbines require inter-array cables to connect strings of turbines to the offshore substation, including the use of dynamic and static cable types. The current market for the Celtic Sea stands at 4.9GW (TCE Leasing Round 5 (4.5GW) plus 4 x T&D sites (400MW)). With a value of c.£1 billion. made up of cables, accessories, and offshore installation costs.1 This will require somewhere in the region of 41km of dynamic and 515km static cables, requiring 3-6 cable, laying vessels.2
Dynamic cable manufacturing capability does exist within the UK, however the scale and demand for floating offshore wind projects will present a significant capacity challenge. The demand for components (cable protection systems, bend stiffeners, buoyancy modules, dry and wet mate connectors etc.) as well as cables may require the expansion of existing, or development of additional manufacturing facilities, which adopt serial production techniques along with the distribution, logistics and ongoing maintenance services needed to access multiple markets The Offshore Wind Industrial Growth Plan has prioritised dynamic cable manufacture as ‘Make’ requiring investment of £30-50 million.3
Dynamic cables, connectors and other ancillary equipment are critical components in floating offshore wind projects, they represent a single point of failure for a turbine. In offshore wind more generally, cable technology has not proved to be as reliable as assumed in design and procurement activity. Issues include damage incurred during handling/installation, fatigue failures, manufacturing issues and cable exposure/re-burial. To date, cables have made up the largest share of insurance claims in the fixed market.4 Fresh thinking is therefore required on dynamic cables for successful and sustainable commercialisation of floating offshore wind.
Prior to offshore deployment dynamic cabling systems will require marshalling, assembly, integration and load out at a port facility. It is typical for some of these components to be assembled at the load out facility, whilst others are assembled on the vessel just prior to installation. These facilities are required to be coastal or on large rivers with direct access to the sea. Key requirements for the development of these facilities are access to a suitably large site (for component storage, laydown and assembly), appropriate specification of quayside and direct access to the sea for the transport of mooring systems direct to the project site.
Cable installation can take place well in advance of turbine installation, however, will require close coordination with project developers and regional Port operators, working in an environment with constrained Port capacity whilst multiple projects compete for quay side and vessels.
