Workers have begun laying cables for a major electricity transmission project in Germany dubbed Suedlink, aimed at delivering wind power from northern Germany to the country’s south.
“As the cables are pulled in, Suedlink is becoming a reality kilometre by kilometre,” said Tim Meyerjürgens, manager at the operator Tennet.
The cable work will start in Heeslingen, a small town roughly halfway between the northern port cities of Bremen and Hamburg.
Construction along the roughly 700-kilometre-long planned route of the transmission line will begin next year.
The Suedlink project is expected to supply up to 10 million households with renewable energy, or roughly as much power as four large nuclear power plant units used to generate, according to Thorsten Dietz, director of current projects at Tennet.
Improved electricity transmission infrastructure is seen as particularly important for the southern German states of Bavaria and Baden-Württemberg, especially since Germany shut down its last remaining nuclear power plants and seeks to close coal-fired plants as well.
Experts believe that the expansion of the electricity grid is necessary as part of the energy transition.
Local activist groups and residents, however, have repeatedly expressed concerns about the massive project and threatened legal action. Among other things, they have expressed fears about the project’s negative effects on agriculture and the environment.
Strictly speaking, the Suedlink project consists of two power connections with four cables. The lines are to begin near the German North Sea coast, join under the Elbe River and then branch out again in southern Germany.
Two of the cables are planned to end in Bavaria, while the other two will terminate in Baden-Württemberg. A total of more than 2,400 kilometres of cable are to be laid across six German states.
Digging and drilling is already under way in some places, said Dietz. From next year, there will be dozens of construction sites nationwide.
“We are building sections and connecting them one by one,” he said.
It will take at least another four years before electricity flows, he said. This should happen by the end of 2028, six years later than originally planned.
“Suedlink can only go into operation when the entire system is ready,” Dietz said.
The company said work crews will be able to move forward at about about one metre per minute. Workers will have to dig 1.3-metre-deep trenches and then lay the heavy underground cable metre by metre across the country.
Drums of the cable weigh several tonnes, and the lorries transporting the cables require special permits.
The cables will be laid in the trenches using cranes and pulled through with a rope.
The trenches will be backfilled with earth after the cable has been laid, and in a few years there should be no sign of the construction site.
The operator has sought to assure the public that the land can then be used for agricultural purposes without any restrictions.
The long-distance transmission project will use direct current to reduce the amount of energy lost, with converters at the end points transforming the power into alternating current for use in the regular grid.
Tennet is responsible for planning and construction in the north of the country, while another grid operator, TransnetBW, is responsible for central and southern Germany.
Laying underground cables has less impact on the landscape than electricity pylons, but is significantly more expensive. The operators estimate that it will cost around €10 billion ($11 billion).
It remains unclear what the future commissioning of Suedlink will mean for electricity prices in Germany, but the project costs will be paid for by consumers through grid charges.
At the same time, the new route should prevent bottlenecks in the electricity supply, which could save money.
In the best-case scenario, no additional electricity will need to be purchased and no additional power plants will need to be ramped up, meaning overall costs could decline.
