Subsea Cables

The growing need for very long length, high voltage (HV) cable systems able to cope with subsea transitions, including power transmission from offshore wind farms and power supplied to offshore oil drilling projects, has opened the way for crosslinked polyethylene (XLPE) insulation. 

With the capability to deliver greater reliability over longer distances, XLPE outperforms traditional lapped, fluid-filled cable, reducing energy losses and offering lower environmental impact. 

To help cable makers and energy distributors realise the full advantage of these materials, Borealis has developed special Superclean™ XLPE insulation compounds and Supersmooth™ semiconductive materials specifically for the manufacture of HV transmission cables in sub-sea operating environments. Superclean™ XLPE insulated cable offers the distributor:

• faster installation;
• lower environmental impact - elimination of fluid leakage risk;
• low dielectric losses;
• better power flow control;
• higher operating temperature;
• improved transmission reliability and reduced risk of network failure.

Cleanliness ensures good electrical performance

Designed for HV operating conditions and system voltages above 36kV, Superclean™ XLPE insulation compounds are produced in contamination-free environments and delivered in Superclean octabins filled and emptied under clean room conditions. This provides the highest level of cleanliness, reduced risk of degradation by contaminants, and consistent performance with long-term reliability.

Importantly for the cable maker, Superclean aids manufacturing through better scorch safety, longer production runs before equipment needs to be cleaned, lower degassing burden, and shorter production cycles by 10-20%.

Semiconductive screening materials add value to HV cable

At higher electrical stresses a smooth interface between insulation and shielding increases the potential for reliable performance and uninterrupted power supply.  Supersmooth™ semicons have been optimised to provide the semiconductive layers on both sides of the Superclean XLPE insulation with very smooth and even surfaces that eliminate surface pips, reduce electrical stresses, and  minimise the risk of power failure.