Denmark and Germany concluded a binational agreement on the Bornholm Energy Island project that establishes a shared funding model and cost‑sharing framework for the hybrid offshore wind hub and its grid links, including the HVDC connection between Bornholm and Zealand. Signed around the 2026 North Sea Summit and highlighted in a European Commission statement, the deal confirms joint financing responsibilities aligned with expected power flows and benefits, underpinning long‑term investment in the multi‑terminal HVDC interconnector infrastructure.
At the North Sea Summit in Hamburg on 26 January 2026, German Energy Minister Katherina Reiche and Danish Climate and Energy Minister Lars Aagaard concluded an investment agreement for the Bornholm Energy Island hybrid interconnector, confirming a shared-cost financing model between Germany and Denmark. Under this deal, the countries will jointly fund construction of the electricity hub on Bornholm and associated subsea and onshore links, including a 2 GW cable from Bornholm to a new German substation in Vorpommern‑Greifswald and a 1.2 GW cable to Zealand in Denmark, with implementation entrusted to TSOs Energinet and 50Hertz and supported by €645 million in EU CEF funding.
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Bornholm Energy Island is a hybrid multi‑terminal HVDC hub developed by Danish TSO Energinet and German TSO 50Hertz to centralise offshore wind generation and transmit it into the Danish and German onshore grids. The project’s strategic role is to integrate large volumes of Baltic Sea offshore wi...
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Energiø Bornholm, Energy Island Bornholm, BEI, Bornholm artificial energy island, Energiø Bornholm project, Energiø Bornholm-Zealand, Energiø Bornholm– Zealand
50Hertz reports on its BEI interconnector project page (last updated January 2026) that installation of the underground cable conduit system for the German land route has already begun. This conduit runs approximately nine kilometres from the port of Vierow on the Greifswald Bodden northward to the planned new transformer and converter station site at Rappenhagen in Mecklenburg-Western Pomerania. Critically, this cable conduit is shared infrastructure: 50Hertz states that the installation has begun "in connection with the construction work for the Ostwind 3 offshore grid connection system", meaning the conduit serves both the Ostwind 3 project and the future BEI Bornholm-Germany HVDC land cable. The BEI cable will be fed into this pre-installed conduit at a later date once BEI-specific construction begins. This is preparatory shared infrastructure rather than the formal start of BEI project construction — FID for BEI has not yet been reached (projected 2027) and BEI-specific onshore works (converter station construction, cable pulling) have not commenced. The conduit work is nevertheless a material physical milestone for BEI as it secures the German onshore cable route corridor and reduces future construction risk and duration for the BEI interconnector.
The European Commission, via the CEF Energy programme administered by CINEA, signed a €645.2 million grant agreement to support the Danish part of the Bornholm Energy Island hybrid interconnector, funding two new converter stations on Bornholm and Zealand and an approximately 200 km submarine HVDC cable plus a 17 km onshore connection between Bornholm and Zealand. The grant, awarded to Energinet for the joint Energinet–50Hertz project, provides capital support that reduces Denmark’s investment burden while enabling up to 3 GW of offshore wind power to be transmitted through the Bornholm hub into the Danish and German grids.
Energinet selected NKT to deliver the 525 kV HVDC on- and offshore power cable systems for the Danish connection between Bornholm Energy Island and Zealand, signing a contract valued at around EUR 650 million. The contract covers design, manufacturing and installation of approximately 200 km of offshore route and 16.8 km of onshore cables, securing the main cable link that will transmit offshore wind power from Bornholm Energy Island into the Danish grid.
Energinet and German TSO 50Hertz signed a contract with Siemens Energy to supply advanced high-voltage equipment for the Bornholm Energy Island interconnector project, including four HVDC converter stations and one HVAC high-voltage station located on Bornholm, Zealand, and in Germany. This contract, valued at over €1 billion, secures one of the largest work packages in the joint Danish-German project and will enable at least 3 GW of offshore wind power from the Baltic Sea to be transmitted to consumers in both Denmark and Germany.
As part of the early public participation for the Bornholm Energy Island interconnector between Bornholm and Germany, 50Hertz scheduled a public consultation meeting on 3 April 2025 specifically for public bodies and local politicians within the German project region, with invitations sent on 10 March.
On 13 May 2024, the Danish Energy Agency published and adopted the Plan for Program Bornholm Energy Island based on a strategic environmental assessment and earlier consultations, establishing the overall environmental and planning framework for the offshore wind farm south of Bornholm and the high-voltage installations on Bornholm and Zealand, including the Energiø Bornholm–Zealand HVDC connection, while noting that separate project-level permits are still required for construction.
Bornholm Energy Island, developed by 50Hertz and Energinet as a hybrid offshore interconnector between Denmark and Germany, is recognised as a Project of Common Interest (PCI) by the European Union, with its status confirmed via inclusion in the 6th Union PCI list that entered into force on 28 April 2024. This EU-level PCI listing supports cross-border electricity infrastructure development and underpins the project’s role in integrating offshore wind and facilitating European power trading.
On 10 April 2024, 50Hertz held an early public participation event in the form of a public information market at the community center in Brünzow, Germany, where the Bornholm Energy Island interconnector project was presented to local residents and interested parties for the first time, including information on the project’s technology and approval steps.
On 30 November 2023, Danish and German TSOs Energinet and 50Hertz started the tendering process for key technologies for the Bornholm Energy Island project, including issuing a major procurement invitation whereby the HVDC equipment for the stations in Germany and Denmark will be tendered as one joint contract that was sent to prequalified vendors on the same day, aiming to reserve production capacity early and maintain the project timeline.
The Danish Energy Agency opened an eight-week public consultation on 2 October 2023 for the Draft Plan for Program Energiø Bornholm and the associated Environmental Report, inviting comments from citizens, stakeholders, and authorities and holding public meetings on Bornholm and Zealand covering the offshore wind hub and its grid connections, including the Bornholm–Zealand link.
On 20 June 2023, Germany and Denmark marked the signing of an intergovernmental agreement for the Bornholm Energy Island hybrid interconnector, establishing the framework for TSOs Energinet and 50Hertz to jointly develop and operate the project. The agreement clarifies ownership rights and allocates responsibilities, with both TSOs committing to equally bear the infrastructure costs, share the renewable energy target volumes, and split congestion revenues from the power lines between Denmark and Germany, while each retains ownership of the interconnector assets to its respective mainland.
From May 2023, Bornholms Museum began conducting archaeological pre-investigations near Aakirkeby on Bornholm as part of the preparatory site investigations for the onshore infrastructure associated with the Bornholm Energy Island project.
RTE International was contracted to perform modelling and simulation requirements and produce specifications to de-risk multi-vendor, multi‑terminal HVDC functionalities for the Bornholm Energy Island project.
Energinet, the Danish transmission system operator, began field and environmental studies on Bornholm and Zealand in connection with the Bornholm Energy Island project, including areas where underground cables and high-voltage substations for the Bornholm–Zealand HVDC link may be installed. The programme involves biologists surveying plants and animals in ponds, lakes, marshes, and meadows along the prospective onshore cable and station corridors between late March and October 2022, with landowners notified in advance.
On 14 March 2022, a regulatory decision was taken to change the figure on soft-start requirements in the preliminary studies for the Bornholm Energy Island, modifying conditions attached to Energinet’s investigation permits for the project.
Bornholm Energy Island was included in ENTSO-E’s Ten-Year Network Development Plan 2022 as European project no. 1106, meaning the hybrid offshore interconnector between Denmark and Germany is formally taken into account in European grid development planning.
On 21 December 2021, Energinet was granted an additional preliminary investigation permit in the Baltic Sea, allowing further preliminary studies to be carried out for the Bornholm Energy Island area beyond the initial campaign.
On 13 October 2021, Energinet received a revised general legal order concerning preliminary studies for Energiø Bornholm, updating and expanding the mandate under which it could plan and execute investigations for the Bornholm Energy Island project.
On 22 June 2021, Energinet received a preliminary investigation permit to start preliminary studies in the Baltic Sea for the Bornholm Energy Island, authorising geophysical, geotechnical and environmental investigations in the designated offshore area.
In summer 2020, Danish transmission system operator Energinet and German TSO 50Hertz signed a cooperation agreement to jointly plan and construct the Bornholm Energy Island hybrid interconnector, including a 1.2 GW connection between Bornholm and Zealand and a 2 GW interconnection between Bornholm and Germany, establishing the project as a binational transmission undertaking.
The Danish authorities issued a legal order on 30 November 2020 instructing Energinet to carry out preliminary studies for the Danish energy islands, including areas on and around Bornholm in the Baltic Sea, thereby formally authorising Energinet to begin site investigations for the Bornholm Energy Island concept.
A public consultation phase was opened in Denmark for the planned high-voltage cable connection associated with the Bornholm Energy Island, inviting stakeholders and citizens to provide feedback on the proposed onshore cable and station works.
A local development plan for the onshore stations serving the Bornholm Energy Island received approval from the council, setting the planning framework for converter and high-voltage station layouts that blend with the landscape and provide recreational value.
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