A project has been launched to make cables used in the offshore wind industry more reliable
The Cable Lifetime Monitoring Joint Industry Project was launched on 8 July 2019 and is a collaboration between more than 30 international organisations that aim to reduce subsea power cable failures and make offshore wind energy more reliable.
Partners in the project aim to reduce the levelised cost of electricity, insurance costs and the CO2 footprint of the offshore industry.
Failures in subsea power cables are one of the main risks affecting offshore windfarm development and operation. They account for approximately 80% of insurance claims in the offshore wind industry. Their impact is so large because cable failures can shut down an entire section or even an entire windfarm.
Cable inspection and repair is expensive. Repairs on cables can easily be delayed for a few weeks or months because of the weather or limited vessel availability, impacting revenue and reducing the technical lifetime of a subsea cable. Reducing the risk of subsea cable failure will make the offshore energy grid more reliable and provide greater control over the costs of the offshore cables throughout their lifetime.
The project was initiated by DNV GL, TNO, BREM, Van Der Hoek Photonics and Deltares in collaboration with 30+ industry partners ranging from international suppliers to system integrators, end users and regulators.
Due to the wide range of partners, improvements will be made in the areas of the design, installation, operations and maintenance of subsea cables. The consortium will create guidelines for transparent, industry-supported practice focusing on the main aspects of subsea cable systems and their failures.
The work will begin with a thorough analysis of the main causes of cable failures. On that basis, improvements can be made in the areas of the design, installation, operations and maintenance of subsea cables.
Another important topic covered by the study is developing lifetime monitoring techniques.
Deltares offshore wind project manager Jan-Joost Schouten said, "By continuously monitoring the cables from installation through to operation using optical fibres, it is possible to establish a picture of why cables fail and develop an early warning system."
In addition, the project partners will improve the predictions of morphological features such as sand waves around subsea cables and develop a decision support tool to quantify the achieved cost reductions for offshore wind energy.
The project will take 30 months and is being supported by the Dutch Ministry of Economic Affairs and Climate Policy through the Netherlands Enterprise Agency. It comes hard on the heels of a call for entries from the Carbon Trust Offshore Wind Accelerator for a subsea cable design study seeking entries from companies and consortia interested in undertaking a study looking into improved cable designs.
A key objective of this study is to evaluate and recommend potential improvements to subsea cable designs for bottom-fixed offshore windfarms and develop specifications of possible future cables.
“Improved cable designs could lead to reduced lifecycle costs due to improved reliability and fewer mechanical failures,” said the Carbon Trust.
The study will also investigate the technical feasibility of surface-laid subsea cables and develop relevant standards and best practice guidelines for improved cable handling.