IEA Wind Task 30 Offshore Code Comparison Collaboration Continued

The IEA Wind Task 30 OC4 (Offshore Code Comparison Collaboration Continuation) project was a continuation of the OC3 project of IEA Wind Task 23 Subtask 2, and was initiated due to the strong interest in continuing the work of OC3. The purpose of the project was to perform a benchmarking exercise of offshore wind turbine dynamics codes. OC4 consisted of two phases that were not considered in OC3: (1) analysis of a wind turbine on an offshore fixed-bottom jacket and (2) analysis of a wind turbine on an offshore floating semi-submersible. Additionally, an experts meeting on the topic of test methods, data availability, and code validation was held as a stand-alone meeting. OC4 was led cooperatively by the National Renewable Energy Laboratory (NREL) and the Fraunhofer Institute for Wind Energy and Energy Systems Technology IWES. NREL was responsible for project management, coordination with the ExCo, project finances, and organization of the topical experts meeting. Fraunhofer IWES was responsible for the technical coordination and reporting of Phase I, while NREL was responsible for the technical coordination and reporting of Phase II. IEA Wind Task 30 lasted for three years. Each phase lasted about two years, with one year of overlap in the middle, beginning with Phase I in the first year. The topical experts meeting was held in the second year. A report summarizing the results was published at the conclusion of each phase, as well as on the results of the topical experts meeting. This report, as well as a technical summary report, are the final reports for the project. While the verification of offshore wind tools through the OC3 and OC4 projects was successful, the participants feel that validating the tools against actual physical data is important. Therefore, an extension of the OC4 project was presented to and approved by IEA Wind for this purpose. The project is officially called the Offshore Code Comparison Collaboration Continuation, with Correlation (OC5), and will begin the process of validating offshore wind modeling tools through the comparison of simulated responses to physical response data from actual measurements. It will start in 2014 and run for 4 years and also operate under Task 30. During the OC4 project, the operating agents found it difficult to get some countries to pay their dues, and suggest a more stringent requirement on payment for participation in the follow-on extension.