NordLink is a proposed bi-pole, high-voltage, direct current (HVDC) interconnector that will link the German and Norwegian power grids, connecting the two main European electricity markets for the first time.
Designed to be Europe’s longest interconnector, NordLink will be developed by Statnett (50%) in collaboration with TenneT (25%) and investment bank KfW (25%). The electricity generated from the project will be able to meet the energy requirements of 3.6 million German homes.
The project will also help in reducing carbon emissions by promoting the exchange of renewable energy and increasing the use of renewables in power generation. By utilising Norway’s vast hydropower and Germany’s wind and solar power, the interconnector will ensure an efficient and secure power supply.
An investment decision on the project was taken on 10 February 2015 and followed by the ground breaking ceremony for the construction of the German converter station on 16 September 2016.
The project is expected to be completed by 2019 and will start commercial operations in 2020 after successful trial operations. The total cost of the project is estimated to be between €1.5bn ($1.68bn) and €2bn ($2.24bn).
NordLink Interconnector details
NordLink will enable Germany to export energy generated from wind and sun to Norway during the dry season, while Norway can export its surplus energy from hydropower to Germany during winters, which will help in facilitating the integration of the European energy market.
The 623km-long cable will have a planned capacity of 1,400MW and will connect the continental ENTSOE grid with the Nordic grid, which have an installed capacity of 600GW and 100GW, respectively.
The interconnector will consist of 54km of underground cable in Germany, 516km of submarine cable and 53km of overhead line in Norway. Its planned route will be between Tonstad / Ertsmyra in Norway’s Sirdal municipality and Wilster in the German Schleswig-Holstein district.
The HVDC system will comprise a bipole configuration with a rating of ±525kV. The converter stations will be located in Wilster and Tonstad, where electricity will be converted between direct current and alternate current and supplied to the transmission grids, for distribution to homes and businesses.
Details of the NordLink Interconnector cable system
Subsea cables in Germany will be buried at a depth of approximately 25m and comprise two parallel mass impregnated cables. They will be installed in a bundled configuration to ensure minimum impact on magnetic marine compasses.
The submarine cables will be equipped with a copper conductor, as well as a paper insulation system and double-steel wire covering. The cable will have an outer diameter of 15cm.
The underground cables will be similar to the subsea cables but without a wire covering, instead being equipped with an extruded polyethylene (PE) sheath. The cables will be delivered in lengths of approximately 1km on cable steel drums and joined onsite.
Contractors involved
Nexans was awarded a €500m ($560m) contract to design, manufacture and install two 525kV cable subsystems. It will also design, manufacture and install mass impregnated non-draining (MIND) HVDC cables at depths of 450m using the cable-laying vessel C/S Nexans Skagerrak. Nexans will use its Capjet system for trenching the cables on the seabed for protection.
A $900m contract for the HVDC converter stations and cable system in Germany was awarded to ABB. The scope of work includes design, engineering, supply and commissioning of two 525kV, 1,400MW converter stations using its Voltage Sourced Converter (VSC) technology.
ABB will also design, manufacture and install a 525kV mass impregnated cable system in the German sector that will encompass 154km of subsea and 54km of underground cable.