Siemens Energy has been awarded a major contract to supply converter stations for the Bornholm Energy Island project, a cross-border energy infrastructure initiative linking Denmark and Germany through offshore wind power.
The agreement, signed with transmission system operators Energinet (Denmark) and 50Hertz (Germany), covers the design, supply, installation, and commissioning of four converter stations and supporting components. These will be located on the Danish islands of Bornholm and Zealand, as well as on the German mainland.
The Bornholm Energy Island aims to connect multiple offshore wind farms in the Baltic Sea to a central hub on Bornholm, from which electricity will be transmitted to both countries. The converters will transform alternating current (AC) to direct current (DC) and vice versa, enabling high-voltage power transmission via submarine and land cables.
“This project lays the foundation for a truly integrated, low-emission energy future,” said Tim Holt, member of the managing board at Siemens Energy. “The power grid is the backbone of a resilient energy system.”
Two converter stations will be built on Bornholm and linked by DC switchgear and a substation. The island will serve as a collection point for offshore wind power, raising it to 525kV for distribution via a 2GW cable to Germany and a 1.2GW cable to Zealand.
The €7 billion project had been temporarily paused during a six-month transitional period to resolve regulatory coordination between the two countries. With this contract, the project moves into its implementation phase.
Funding support has been granted by the European Union, with €645 million provided to Energinet through the Connecting Europe Facility (CEF), reflecting the project’s role in supplying clean electricity primarily to Germany.
“Today, important foundations have been laid to make the Bornholm Energy Island vision a reality,” said Stefan Kapferer, chief executive of 50Hertz.
Energinet chief executive Thomas Egebo added, “We are taking a big step forward into a future in which offshore wind from the Baltic Sea supplies millions of consumers with electricity… Energy that will make both Denmark and Europe greener and less dependent on external energy sources.”
Permitting processes have begun in Denmark, including preparations for public hearings by the Danish Environment Agency. In Germany, the approval process for cable routes through territorial waters and land is still pending.
