FEATURE
IMPACT OF ADDITIONAL INSTRUMENT AND SENSOR INFORMATION ON SUBMARINE CABLE INSTALLATIONS
BY VENKATA JASTI AND JOSE ANDRES
O
ffshore wind is already a key contributor of power in the European Union. The United States Department of Energy (DOE)’s Wind Vision goal is for offshore wind to supply 86 GW of US electricity by 2050; approximately 5 times the existing offshore wind capacity worldwide. Each windfarm development will involve planning and installation of array cables that inter-connect turbines, and longer export cables that bring the power from the wind farm to the shore. Similarly, Ocean Bottom Cables and Node on Rope systems (collectively called Seismic Arrays in this article going forward) are proven methods used world-wide for Subsea Hydrocarbon Exploration as well as Permanent Reservoir Monitoring. The Seismic Arrays are installed and recovered multiple times during these projects. Hence, submarine cable installation is a significant and impactful step for both these industries. The installations of power cables are monitored more heavily using ROVs or other emerging technologies, due to the high cost of cables, bending limits, and tension restrictions. In the case of Seismic Array installations, the
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SUBMARINE TELECOMS MAGAZINE
required installation accuracy is very stringent. To achieve this level of accuracy, several USBLs are added along the array, which provide additional positional feedback as the array is being installed. Adding USBLs to the array is viable due to the fact that arrays are not permanent installations, and all the array hardware can be recovered. In both these cases, there is clear economic justification for the expenses of adding additional instruments, and operating them in real-time to assist with submarine cable installations. The rest of the article discusses what some of these instruments are and why pairing them with a real-time control software like MakaiLay, built on a dynamic, 3D, fast and rigorous physical model of the cable, is a beneficial approach.
WHAT ARE SOME OF THE ADDITIONAL INSTRUMENTS AND SENSORS?
The following is a non-exhaustive list of Instruments and Sensors being used during Power Cable and/or Seismic Array installations. Note that some options listed below are established industry practices while others are newer and