10390 Design validation of ICCP systems for offshore wind farms

Wednesday, March 17, 2010: 1:25 PM
210 A/B (Henry B. Gonzales Convention Center)
Leslie Bortels*1, Jacques Parlongue1, Joop de Leeuw2, and Bart Wessels2
(1)Elsyca NV; (2)Corrosion & Water-Control
The Greater Gabbard Offshore Wind Farm is the world's largest offshore wind farm project (500MW) to move into the construction phase and will be built approximately 25 kilometers off the Suffolk coast of the United Kingdom (UK). The construction work started in summer 2009 and features 140 wind turbines each having a rated capacity of 3.6 MW. The turbines are mounted on steel monopiles and transition pieces in water depths between 24 and 34 meters.
The selection of the optimal cathodic protection system was based on extensive computer modeling. The simulation campaign compared ICCP, SACP as well as combined approaches against operating parameters taking into account calcareous layer erosion, flow rate dependant polarisation behavior and layers with changing resistivity. In addition, the dissolution effect of the sacrificial anodes and remaining lifetime of the MMO anode pastilles has been simulated.
This presentation details the results of the comparison study of the various cathodic protection systems as well as the initial field measurements of the installed design.