Siemens has been awarded an order for a high-voltage direct current (HVDC) transmission system to connect the British and Belgian national grids via subsea cable. Siemens will be responsible for the turnkey installation of both converter stations using HVDC Plus technology with a transmission voltage of ±400 kilovolt (kV) DC.
Customer is Nemo Link, a joined venture between the British grid operator National Grid and Belgian Transmission System Operator Elia Group, who together have founded this joint project. After its completion, Nemo Link will provide 1,000 megawatt (MW) of capacity, enough to power 500,000 households.
The link will run 140 kilometers (km) between Richborough on the Kent coast and Zeebrugge near the city of Brugge with a combination of subsea and underground cables. Commercial operation of the link is scheduled for 2019. The contract also includes a service and maintenance agreement for a period of five years.
Using subsea cables Nemo Link will connect two high-voltage alternating current (HVAC) electricity systems separated by the North Sea. The utilization of HVDC avoids the need to synchronize the two interconnected AC networks. Both converter stations will be using HVDC Plus voltage-sourced converters in a modular multilevel converter arrangement (VSC-MMC) that convert AC to DC and DC back to AC on the other side of the link.
The Nemo Link interconnector will allow power to flow in both directions and will be the third electricity connection between UK and Europe. The 1,000-MW-interconnector BritNed between UK and the Netherlands was also developed by Siemens and went into operation in 2011.
Image: teshmont