Offshore wind farms in the Baltic Sea supplied around 5400GWh of electricity to the east German extra-high-voltage grid via 50Hertz’s offshore connection systems in 2025.
The transmission system operator said this represents year-on-year growth of about 10% and is sufficient to cover the electricity demand of Leipzig and the surrounding region.
According to 50Hertz, the increase was driven by continued offshore expansion off the coast of Rügen. The 450MW Baltic Eagle wind farm is now delivering its full output through the Ostwind 2 grid connection following the earlier commissioning of the 250MW Arcadis Ost 1 project.
The company noted that offshore generation in its grid area has risen steadily, increasing from 4300GWh in 2023 to 4900GWh in 2024, before reaching the new record level last year.
Stefan Kapferer, chief executive of 50Hertz, said the Baltic Sea is playing an increasingly important role in Germany’s energy system.
“The Baltic Sea is not only a fantastic holiday destination. Its role in security of supply and climate protection in Germany is becoming increasingly important,” he said.
Kapferer added that further growth is already in the pipeline, with Iberdrola’s Windanker offshore wind farm scheduled for commissioning in the second half of 2026.
He said the largest offshore wind farm in the Baltic Sea to date — Skyborn Renewables’ Gennaker project — is expected to be connected to the grid in 2028.
“In addition, 50Hertz will also provide access to wind power outside German waters in cooperation with its Danish partner Energinet, including through the Bornholm Energy Island joint project,” Kapferer stated.
While offshore output increased, 50Hertz reported a decline in onshore wind generation within its control area. Onshore yield fell by around 2000GWh in 2025 to 33,800GWh, which the company attributed to weather conditions, despite additional turbines being installed.
