The EU Green Deal calls for a rapid and efficient green transition. On-going climate change and an increasing need for secure and sustainable energy means ambitious projects and goals are accelerated. To expand and exchange offshore wind energy across North Sea neighbouring countries, the Danish government presented in 2020 the Danish North Sea Energy Island (NSEI) project. This pilot project illustrates the shift from ‘nationally individualistic’ modes of connecting offshore wind energy projects, to supplying a multi-lateral renewable offshore energy grid. The Energy Island project builds on the Hub-and-Spoke (H&S) approach, which introduces a new level of complexity to governing the next generation of offshore wind energy projects. This paper analyses the political motivations for the Danish project and the planning and implementation of the Energy Islands, integrating a combination of collaborative and transboundary governance perspectives. The qualitative analysis is based on a document analysis and a literature review. Findings show how planning for the Danish Energy Island has faced delays and challenges, causing uncertainties about the Island’s capability to support Green Deal goals, as well as a mismatch between political ambitions and practical implementation. The artificial offshore island is currently under reconsideration due to costs and is, as of March 2024, still in its planning phase. This case study on the Danish NSEI serves as an introduction to the general functionalities and development of the Island and defines a Danish Energy Island. Results indicate that the combination of transboundary and collaborative governance structures are necessary as part of a successful implementation of Energy Islands.