RE: Im emailing Tekmar1 May 2021 10:20
'The method where the inter-array cables were left unstabilised was adopted industry-wide at the time.'
https://www.offshorewind.biz/2021/04/30/orsted-points-at-possible-reason-for-eur-403-million-cable-problem/
The issue occurs when the cable protection system (CPS) moves across the scour protection, the rocks placed on the seabed around the foundations to avoid seabed erosion, abrading the CPS and in the worst-case scenario causing the cables to fail.
It appears now that the second layer of rock placed on top of the cables could have prevented the damage to the CPSs.
”For the first many wind farms we built we had another solution. First we had rocks around a monopile, then we had a cable coming out, and then we put rocks on top again,” Marianne Wiinholt, Ørsted’s Chief Financial Officer, said in a conference call about the company’s Q1 2021 results.
”Then, together with the industry, we thought that there was a better solution, and therefore we did not put the additional second rock layer on top. That was believed to be the best solution and we used that for ten of our wind farms. We have now found out that this is not a good solution, so for the wind farms we are constructing now, Hornsea Two and Changhua 1 & 2a we are stabilising the cables again.”
When asked if this could be a generic problem for offshore wind operators and owners, Wiinholt said that the method where the inter-array cables were left unstabilised was adopted industry-wide at the time.