The Powerkite project is developing a power take-off system (PTO) for a novel tidal energy converter by Swedish developer Minesto known as Deep Green. One of the key deliverables of the project was to develop a conceptual design of the complete offshore array system including substations, cables and grid connection, with the aim to assess the key parameters of the future tidal plant (electrical efficiency, protection systems, fulfilment of requirements from network owners, cost, etc.), without going into a detailed design.
A base case array design was defined with focus on a short time to implementation and low cost, with standard technology as far as possible for the array infrastructure. Relevant standards, regulations and other requirements were identified, based on the assessment that it is an off-shore installation, and the choice of Holyhead Deep site off the coast of North West Wales as reference site.
An array design was developed in steps of 3, 12 and 80 MW. The base concept design was defined as 6 kites (3 MW total), connected to one Tidal Marine Substation (TMS). A floating buoy solution was chosen for the TMS. The design of the tidal power array is established and refined using electrical modelling and simulations. In addition, a base design of the TMS buoy hull structure, layout of electrical equipment, cable handling and mooring solution was achieved.
This first conceptual design study has identified a number of key design issues, both for array and the kite. These are being addressed in the current project and/or will be fed into to the future development.
Alternative technological solutions are explored for future performance improvement and reduced costs of the kite and the system.