As the demand for green energy continues to grow, offshore energy operators have an expanding network of subsea power cables to monitor and maintain.
With cable outages disappointing customers and costing operators a great deal of time and money, preventing cable failures, and quickly identifying and planning for the repair of damage is vital.
With Fotech’s smart cable monitoring solution, you can monitor your subsea cables in real-time and effectively target repair operations and pre-emptive maintenance.
Using optical fibres with the cables, you can monitor subsea cables automatically, 24/7, giving you enhanced and continuous visibility of integrity issues across your subsea cable network.
Fotech’s Distributed Acoustic Sensor (DAS) technology converts one of the optical fibres already present in most offshore cables into a state-of-the-art sensor which can detect vibrations along its length. Events such as cable motion in the water, insulation breakdown, and anchor strikes all generate strains, or vibrations with distinct characteristics. Fotech’s smart cable monitoring solution monitors these strains or vibrations. Each is analysed by cutting-edge software to provide continuous and accurate real-time information along your cables. And by using advanced artificial intelligence (AI) to automatically monitors the cable, filtering out complex background noise, to deliver alerts on risks to your cable and inform maintenance needs.
LiveDETECT® Subsea Cable Applications
Fotech LiveDETECT II® equips offshore cable operators to monitor and protect:
Subsea Cable Exposure:
Identifying acoustic vibrations and strain that indicate loss of burial, so that the cable can be reburied before damage occurs.
Subsea Cable Arcing:
Detecting the initial impulse and subsequent shock waves that indicate cable insulation breakdown, so that a targeted repair can be planned.
Subsea Cable Strikes:
Detecting events such as anchor strikes, drag, or trawlers in the vicinity. LiveDETECT II®’s cable monitoring data can be cross referenced with ship location data so that vessels can be alerted, and damage avoided. Plus, integration with security systems such as UAV drones can identify parties responsible for the damage so that compensation can be sought where appropriate.
Subsea Cable Maintenance:
Identifying offshore cable problems that periodic inspection may miss. Remotely operated underwater vehicles (ROVs) or divers can be deployed with precision to targeted areas.
Cable downtime is costly but finding the areas of risk or damage over many kilometres of cable is a challenge. Fotech’s smart cable monitoring solution allows you to confidently monitor your cables in real time and detect potential problem areas to within a few metres.
Fotech’s powerful software and advanced AI technology filters out the background noise and ensures that you are alerted to the events along the cable that matter.
Maintaining cables is itself a complicated and costly project. Due to the changing nature of the subsea environment, periodic ROV passes or bathometric surveys can miss potential problems. DAS’s continuous monitoring can give you an early warning to these problems, allowing you to target your maintenance programme and reduce costs.
Offshore Cable Monitoring Case Study: Minimising Downtime and Repair Costs
The increasing demand for renewable energy is creating pressure on operators to enhance the robustness of growing subsea cable networks.
In a recent case study, offshore cable operators detected a fault in the cable network supporting an offshore wind farm. They were keen to locate, analyse and repair the fault in the most cost effective, fast, and safe manner. So, they deployed Helios DAS® by Fotech to convert the fibre optic line located within the three-core subsea cable into a powerful acoustic sensor.
Combined with flashover and spatial calibration tests, Helios DAS® pinpointed the location of the subsea power cable fault with 1 metre accuracy. This allowed diving engineers to minimise the section marked for repair to just 3.5 metres. They carried out the repair just before the weather turned dramatically. If conventional cable fault finding techniques – with a much longer time window – had been employed, the knock-on effect would have been a delay of at least one month.
As a result, Helios DAS® saved the customer millions of pounds in downtime, loss of service and loss of productivity.