Alternatives for the Design of Grid Connection Infrastructures for Wave Energy

Abstract: This work was carried out as a first feasibility study for the Biscay Marine Energy Platform (bimep) and concerns the preliminary assessment of different alternatives for the connection of wave energy converters to the grid applied to the specific case of the Basque coast at water depths between 50 and 90 metres. The size of the farm is about 20 MW but the connection is performed through four different 5 MW cables to shore.

The objective is the definition of the best solution for the connection of several wave energy devices to the 5 MW cable. The criteria for the selection are based on qualitative engineering assessment methods as well as hydrodynamic performance and mooring responses using common methodologies and offshore recommendation practices. Four different solutions were taken into account:

• Connection of the umbilical to a secondary dynamic cable and further to a submerged hub placed on the seabed
   
• Floating platform connecting umbilicals and 5 MW cable to shore
   
• Connecting platform as the previous one but mounted on pile or gravity foundations
   
• Connecting platform placed at an intermediate depth below the surface

A feasibility study was carried out to define all the main components of each solution and identify preliminary budget estimation.