Risø has been monitoring wind resources and power output from offshore wind farms since 1993. A considerable degree of expertise has been developed in optimizing measurements and in using these databases to develop and validate models for offshore environments. This paper describes the evolution of monitoring strategies to a fully automated satellite based retrieval that provides near-real time access to offshore data, even at remote stand-alone masts. An overview of wind speed and turbulence at offshore sites in Denmark is given. Finally, three methods of generating long-term wind resource estimates from short-term measurements are outlined.

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