Optimising the Design of Offshore Wind Farm Collection Networks

Wind turbines have reached a stage of maturity such that their use in offshore applications is becoming common. A principal objective of the offshore wind farm developer is to implement the wind farm to give the lowest cost of energy over the lifetime of the project, thus ensuring the greatest return on investment. Economic performance of the turbines is paramount, but the performance of the electrical infrastructure can comprise a significant portion of total project costs, typically 10-20%. This paper reviews the principles of offshore wind farm collection system economics and outlines methods to optimise the turbine layout, location of offshore substations and the sizing and design of the wind farm collection network. It considers the economic impact of cable size selection and the potential benefits for using multiple offshore substations, with a view to minimising lifetime ownership costs of the scheme without compromising or operational technical requirements