Remedial work on the cable protection system (CPS) on inter-array cables at an offshore wind farm in the UK, owned by RWE, is set to start in the next couple of days, following the discovery of a defect CPS at several locations within the wind farm site earlier this year.
The work, scheduled to commence on 8 October, will be carried out at 20 locations in the North and South fields of the Galloper offshore wind farm.
The vessel EDT Jane will be used for the operations at the wind farm site, located some 30 kilometers off the coast of Suffolk, where the work will be taking place for around ten days.
The 353 MW Galloper comprises 56 Siemens Gamesa 6.3 MW turbines. The wind farm generated its first power in November 2017 and was officially inaugurated in September 2018.
The first inter-array cable CPS fault at RWE’s offshore wind farm was discovered on the scour protection around one of the project’s wind turbine foundations at the beginning of the year. A subsea survey carried out in February found evidence of sections of cable exposure in ten areas over seven cable routes.
While remedial protection work was initiated a few months later, another survey performed in May discovered further 19 locations that have the same defect.
Back in June, following the news from Ørsted that several of its offshore wind farms were affected by a CPS defect, RWE confirmed to our sister site OffshoreWIND.biz that it was looking into the potential CPS issues across its own offshore wind farms.
“We are aware of the specific issues with CPS and have been analyzing potential issues on our fleet of offshore wind parks”, a spokesperson for RWE told OffshoreWIND.biz in June. “We have identified a limited number of locations in rather new assets, including Galloper, that may be affected. We have already identified and are taking steps to introduce remedial measures that will not have a material impact on RWE”.
In Ørsted’s case, the developer explained that the issue at its offshore wind farms occurred when the CPS moves across the scour protection, abrading the CPS and in the worst-case scenario causing the cables to fail.
To protect the cables and reduce the financial impact that has been estimated to be around €403 million, Ørsted decided to implement a “band aid” solution , which involves divers placing a cover over the cables that could potentially eliminate the need for all of the damaged cables to be fixed or replaced.