In 2006, TenneT entered into construction of the 700 MW
NorNed undersea
HVDC submarine power cable with the Norwegian transmission operator
Statnett. Commercial operation of the link was delayed by poor weather and a break in the cable, but it eventually entered operation on the night of 6 May 2008. Connecting the Norwegian and Dutch grids at
Feda and
Eemshaven, the ±450 kV
bipolar cable is, at , the longest undersea power line in the world. During the first two months of test operations, it generated approximately
€50 million in revenue, greatly exceeding estimates, and recovering 12% of its cost of construction. Operations began on 1 April 2011, and as of January 2012, electricity flow has mostly been from the Netherlands to the UK. The BritNed interconnection is seen as a vital link for the foreseeable
European super grid project. A 700 MW submarine power cable called
COBRA (like NorNed, also from Eemshaven) to
Denmark is operated with
Energinet.dk from 2019, signing contracts with Siemens and Prysmian in 2016. Further 3½ GW offshore DC links are intended to provide a sea grid structure, and 6½ GW AC links are planned between Netherlands and Germany. Its subsidiary Transpower Stromübertragungs together with
Statnett operates the 1400 MW
NORD.LINK cable between Norway and Germany from 2020. TenneT builds the 2 GW SuedLink, an onshore DC link between Hamburg and south Germany (near Frankfurt), but local opposition means that a timeline is unclear. Both SuedLink and NORD.LINK are on the EU "Projects of Common Interest" list, and SuedLink is supported by EU with €40 million. TenneT plans onshore AC upgrades in North Germany, connecting new wind power to some of the above DC links.
Dogger Island s in the North Sea In 2016, TenneT suggested a 6 km2
artificial island in the Dutch corner of the
Dogger Bank in the middle of the
North Sea, connecting several GW of offshore wind farms with
alternating current. Converters on the island would then transmit
direct current to the countries around the North Sea in a more economic manner than if each wind farm had its own cable to the country building it. TenneT called for feasibility studies in 2017, and signed an agreement with Energinet. The challenge of coordinating several DC links is studied by the
Technical University of Denmark using the
Kriegers Flak connector as an example.
Suedlink In Germany, most of the wind-power generation is located in the North, while most of the solar power plants are in the South. , cases of deficit of wind power in the North require using gas and coal powered power plants, even if the solar power is abundant in the South, and vice versa. To allow for a more robust redistribution of electricity, an almost 700 kilometer
high-voltage direct current transmission line called "Suedlink" (sometimes spelled "Südlink") is planned to be built, connecting North of the country to its South. The
overhead power line was originally planned to be finished in 2022. However, amid protest from local residents, the plan had to be converted to an
underground power delivery system, and scheduled to be finished in 2028. It is expected to provide four
gigawatts of electricity to around 10 million households. The new plan continues to be protested by residents and land owners close to the route of the line. Opponents of the power line cite damage to the environment and habitat, loss of the development opportunities for the local communities as arguments against it. Demonstrators' claim is that instead of big distributors like TenneT, Germany should rely more on a decentralized system of
photovoltaics,
wind energy and
hydrogen. ==See also==