Key link under the Elbe in Germany's north-south power line completed

Politicians from the northern German states of Schleswig-Holstein and Lower Saxony on Monday marked the symbolic breakthrough of a tunnel under the Elbe that will provide a key link in an electricity superhighway currently under construction.

Schleswig-Holstein Premier Daniel Günther and Lower Saxony Environment Minister Christian Meyer, were present to open the SuedLink tunnel between Wewelsfleth in Schleswig-Holstein and Wischhafen in Lower Saxony.

When complete the 700-kilometre power line will carry wind power generated in Schleswig-Holstein through Lower Saxony, then on to Thuringia and to the southern states of Bavaria and Baden-Württemberg.

The entire route, a major part of Germany's shift to renewable power, will run underground. The project consists of two power lines that will run largely in parallel but branch off at their starting and ending points.

All sections are expected to be completed by the end of 2028 - six years later than originally planned - according to grid operator TransnetBW. Once construction is complete, an estimated 8.5 million cubic meters of earth will have been moved.

SuedLink will also be able to transport electricity generated by solar installations in southern Germany to the north or, in combination with other transmission lines, bring electricity generated by Norwegian hydropower to Germany.

It is also intended to help meet expected increases in demand. In theory, the connection will be capable of supplying electricity to 10 million homes.

At full capacity, SuedLink will be able to carry up to four gigawatts of electricity, according to TransnetBW, roughly equivalent to the output of four nuclear power plants.