The German Suedlink grid project is set to treble in cost due to a decision by the government to use underground cable instead of overhead power lines.

The public resistance to overground power transmission of the vital link means certain southern regions are in danger of power blackouts.
The German Suedlink grid project
Bavarian nuclear power plants are set to be phased out by 2022 yet the link itself, bringing renewable energy from northern Germany, is not expected to be fully operational until 2025.

Transmission system operators TenneT with partner TransnetBW are performing the development of the 800 km direct current line, which will provide combined capacity of 4 GW to ship power from the windy north to Germany’s industrial south.

In a joint statement, the two TSOs published a new possible underground corridor for the power link, calling the new 2025 completion date an “ambitious timetable.”

The statement did not mention costs, but a report in Munich-based Sueddeutsche Zeitung quoted a tripling of the initially estimated costs of Eur4 billion ($4.4 billion) for the project.

The TSOs will now start a first public consultation with communities impacted and hope to file the planning application with the federal grid regulator in the first quarter of 2017.

Platts reports that around 8 GW of nuclear capacity will be closing in the two southern states of Bavaria and Baden-Wuerttemberg in 2022, and planning must take into account that potential shortfall of energy before the link is completed.

According to a German ministry report released this week, 85% of all grid expansion projects are on track to be completed by 2020 with the remainder on track for 2025 and only the new planned interconnector with Poland delayed to 2030.

The slow progress of the grid expansion to date has forced the government to scale back its renewable ambitions with the latest reform of the EEG (Renewable Energy Law) calling for a slower speed in wind expansion especially in so-called grid-bottleneck regions already saturated with new wind turbines.