Scotland-headquartered engineering services company Wood has led a joint industry project to improve knowledge and understanding of how submarine cables affect the marine environment.
The study gathered key industry players including EDF Energies Nouvelles, RTE, Bardot Group and DNV GL and it has spent the last year developing a new set of industry guidelines.
Submarine cables connect renewable energy sources such as offshore wind and wave and tidal power projects with the grid. However, it is acknowledged that existing guidelines were originally derived from the oil & gas industry and are more suited towards assessing the stability of pipelines.
Wood said this anomaly “can result in overly conservative designs with onerous recommendations and the need for expensive stabilisation systems which could, in turn, jeopardise the financial viability of new projects”, so the project has developed a new set of industry guidelines.
This new methodology, which is based on numerical models calibrated with laboratory tests performed in the wave and current basin of the Oceanide test facility in the south of France, provides advice on assessing subsea cables on-bottom stability on rocky and non-smooth seabed.
This comprehensive parametric description of the physical mechanisms driving cables stability resulted in the implementation of an advanced methodology for on-bottom stability analysis with a significant gain in conservatism compared with previous standards.
Bob MacDonald, chief executive of Wood’s Specialist Technical Solutions business, said the joint industry project “has really demonstrated the importance of industry collaboration. Our findings have acknowledged that there were over-conservatism issues but by working together we have developed a new set of guidelines which will ultimately deliver significant improvement of costs for both OPEX and CAPEX.”
Olivier de La Laurencie, St Nazaire offshore wind project director at EDF Energies Nouvelles, said the project “contributes to improve the competitiveness of the offshore wind sector and has provided a fair improvement on decreasing the level of the conservatism of the existing standards”.