The last section (22km) of the 260km long BritNed sub marine cable, a new electricity connection between the UK and The Netherlands, has been placed safely on the seabed. The cable laying works started in September last year and were carried out in six sections. The next phase will involve creating three offshore cable joints and another four land joints and burying the recently installed cable, which should all be completed by the end of September.
The two HVDC marine cables are bundled together and buried below the bottom of the North Sea using special cable laying vessels and a range of support vessels. The cables are buried at least a meter below the North Sea floor. Water depths can be down to some 50 m. BritNed cable is a bi-pole high voltage direct current (HVDC) electricity interconnector with a pair of high voltage cables bundled together. Due to the distance involved (260 km) direct current (DC) is used to transmit power through the cables that connect the converter stations on both sides. These stations were built by BritNed at the Isle of Grain in Kent (Great Britain) and at Maasvlakte – near Rotterdam (The Netherlands). At these locations, the electricity is converted back into alternating current (AC) and connected to the British (400kV) and Dutch (380kV) grids.
Cable facts & figures
- Voltage: ± 450 kV DC
- Cable capacity: 1.000 MW
- Weight 44 kg/m (single cable)
- Length sea cable route: 250 km (two cables, bundled)
- Length land cable route: 7 km (NL) and 2 km (GB), two cables, laid together
- Conductor: 1 x 1430 mm2 Cu (copper)
ABB High Voltage Cables has been responsible for producing and laying the cable on behalf of BritNed.