Orsted has unveiled plans for a 5GW offshore wind hub connecting Denmark, Poland, Sweden and Germany, supporting large-scale production of green hydrogen and creating what it called "the world's first energy island" on Bornholm in the Baltic Sea.

The global offshore wind pacesetter wants to kick-start the massive cluster with a 1GW wind farm in the Rønne Banke zone southwest of Bornholm, one of the areas already earmarked by Denmark for possible future development.

Orsted on Monday urged the Danish government to hold a tender for developing Rønne Banke as the next stage of its offshore wind expansion programme, after the awarding of the Thor project, tendering for which is currently underway.

Orsted said such a tender, in conjunction with new interconnectors between Denmark and Poland – as previously proposed by Danish grid operator Energinet – would shift the agenda for offshore wind to one based around clusters serving multiple countries, including so-called ‘energy islands’ of the type already mooted for the North Sea, but in this case a real, rather than artificial island.

The initial 1GW could later be expanded to 3-5GW, with interconnection extended to Sweden and Germany, said Orsted, which offered no specific timeline for the Bornholm vision, but said it could help Denmark meet 2030 emissions goals.

Martin Neubert, CEO of Orsted Offshore, said: “Offshore wind clusters with transmission to several countries are a necessity if we’re to realise offshore wind’s enormous potential in making Europe green.

“Before constructing large artificial sand islands in the North Sea, we suggest combining existing deployment plans for transmission and designated offshore wind areas with an existing granite island, namely Bornholm.”

The Bornholm cluster would help produce the vast levels of power needed to electrify transport and heating in Denmark and the other nations it serves, said Orsted, citing EU estimates that 450GW of capacity will be needed. Allying the cluster with green hydrogen production would bring a further dimension by supplying clean fuel to help green hard-to-decarbonise sectors like heavy transport and aviation, it added.

Speaking on the sidelines of the Recharge Summit in Copenhagen, Christina Aabo, Orsted’s head of R&D, said the Bornholm proposal represents “the next step in scale and innovation” of the sort offshore wind needs to take in the coming years.

The Danish government has been contacted by Recharge for comment on Orsted's proposal.