Unique floating wind turbine model tests at MARIN, The Netherlands

Testing of three different floating wind turbine concepts for the DeepCwind Consortium (USA), led by the University of Maine. It is for the first time in the world that such an extensive scale model test campaign is conducted in this field. Floating wind turbines are considered to be the next step in development of offshore wind energy, after the present generation shallow water fixed wind turbines. For this unique model tests MARIN and the DeepCwind Consortium worked closely together to develop a new high quality wind generation machine in the MARIN testing facility.



Floating wind turbines allow wind energy generation in deeper areas with more wind and more space. However, selecting the most economical platform with minimized motions is an important technical challenge. This is why DeepCwind is testing a Spar, a Tension Leg Platform and a Semi-submersible at MARIN. The scaled-down model tests are an early part of Phase 1 of the Maine Deepwater Offshore Wind Plan, which aims to have a commercial floating wind farm in the Gulf of Maine by the year 2030 generating 5,000 megawatts of energy. The tests are of great importance for successfully developing floating wind turbines in the future.

Erik-Jan de Ridder and Arjen Koop, responsible Project Managers at MARIN, state that “a key point in these tests is that wind and waves are present simultaneously, allowing the study of the complex motions and loads of the rotating wind turbine on a moving platform in both wind and waves. Therefore these tests serve as high quality benchmark data to validate simulation methods for the coupling between aerodynamic and hydrodynamic behavior”.

Richard Kimball Associate Professor of Engineering at Maine Maritime Academy and responsible for the aerodynamic design: “Although the model tests results need further analysis, the first observation is that the aerodynamic wind loading on the rotor has a considerable influence on the behavior of the floaters and will impact the design and operation of the turbine, showing the importance of the developed high quality wind generation machine in combination with waves”. The set-up was designed in close co-operation between the University of Maine and MARIN. The test results will now be further analyzed in close corporation between both institutes for the three tested floaters which include a spar buoy, a tension leg platform and a semi-submersible. The results will then be used to calibrate and validate simulation codes for floating wind turbines.

The next step of the DeepCwind consortium is to deploy a floating wind turbine design at a 1:3 scale in July 2012 off Monhegan Island, and additional designs at the 1:3 scale in July 2013. Data from these tests and the validated numerical simulation models will be available to help select and optimize the most cost-effective floating wind turbine design concept.

Source: MARIN