Seven European transmission system operators have signed an agreement committing them to standardising interfaces and technology in offshore transmission systems and to adopt a ‘busbar’ concept rather than point-to-point connections
The partners in the project include 50Hertz Transmission and Amprion in Germany; Svenska Kraftnät, Sweden; Red Eléctrica De España, Spain; RTE, France; Statnett, Norway; and Terna in Italy. There are, however, some notable absentees from the list of those participating in it, including TenneT, National Grid and Energinet.
Dortmund-based Amprion first put forward the European Offshore Busbar (Eurobar) ‘networking concept’ for offshore windfarms in June 2020. The aim is to integrate power from offshore wind into the European grid in such a way that it makes the best possible contribution to climate objectives in Germany and the rest of Europe, transitioning from point-to-point connections of the type used to-date to an interlinked network or ‘busbar’ approach.
The busbar concept is a modular one and is designed to be implemented by TSOs around Europe using internationally agreed standards for interfaces and technology.
Adopting the Eurobar concept, the TSOs hope to connect offshore windfarms more efficiently. The participants in the project believe that adopting a busbar approach will also reduce the environmental impact of transmission systems and of interconnecting offshore wind clusters.
“The aim is to develop and implement a joint approach for offshore infrastructure systems, connecting future offshore wind capacity to Europe’s transmission system,” said 50 Hertz in a statement. “Standardised interfaces will ensure that technology is ‘offshore grid ready.’”
Describing the background to the project, 50Hertz chief financial officer Marco Nix said, “The Combined Grid Solution (CGS) adopted for the Kriegers Flak project points the way for transmission systems.
The CGS implemented at Kriegers Flak connects two offshore substations in the Baltic. It also connects to existing onshore connections for windfarms. As a result, the CGS can transmit power to Denmark or Germany and can also be used for cross-border energy trading.
“We want to build on this concept and jointly implement the Bornholm Energy Island project if it is economically and technically feasible. This would then be the second electricity hub in the Baltic Sea and a blueprint for electricity grids at sea,” Mr Nix said.
In January 2021, 50Hertz and Energinet signed an agreement to carry out studies to identify whether it would be advantageous to construct an interconnector between Germany and Denmark, using the island of Bornholm as an ‘energy island.’
Electricity from offshore windfarms in the Bornholm area would be fed into the interconnector. In subsequent phases of the project, connections to other states and offshore windfarms in the Baltic could also be developed.
The windfarms will be constructed approximately 20 km to the south and southwest of Bornholm and connected to a hub on the island.