News, Power Generation & Electrical

Statnett and TenneT recently completed a subsea interconnection between Norway and the Netherlands.

The NorNed-cable connects The Netherlands and Norway. The project has been executed by the two national Transmission System Operators, TenneT and Statnett, as equal partners.
NorNed is an open interconnection. The capacity will be available to the market through an explisit auction, until a market coupling is established between the Nordic and the Dutch power exchanges Nord Pool and APX.
The interconnection is regulated, meaning that the costs and revenues related to the project will be attributed to the grid customers. According to our calculations, the expected revenues are sufficient to cover the costs with acceptable margins.
NorNed is a prioritised infrastructure project under the EU Trans European Networks (TEN) programme.
The decision to build the interconnector was made at year-end 2004, and it was completed in May 2008, four months delayed due to a fault on the cable that occured before Christmas 2007, and bad weather for repair works at the North Sea during the following winter.
Facts and figures
Cable length: 580 km
Total project development costs:   Approx. EUR 495 million
Cable capacity: 700 MW (megawatt)
Land terminals are established at Feda in the municipality of Kvinesdal (county of Vest –Agder, Norway) and Eemshaven (The Netherlands)
Weight: Single-core cable = 37,5 kg per m; two-core cable = 85 kg per m 
Voltage level: 450 kV (kilovolt) 
Maximum sea depth: 410 m
The cable is either buried in the seabed, with the use of a special remotely-controlled excavator based on waterjet technology, or covered by rock.
Along the seabed route the cable crosses 18 other objects such as gas pipelines and telecommunications cables. At the crossing points the cable is protected by a riprap rock covering.
Cabling consists of 270 km two-core cable (bundled) and 2 x 310 m stretches of single-core cable.
Transmission losses are calculated at four per cent for full utilisation at 700 MW (megawatt), a rate which is particularly low for a cabling distance of 580 km.