The United Kingdom and Japan have agreed to invest up to £9bn ($12.1bn) in offshore wind development, according to Splash247 Maritime. The Offshore Wind Compact, signed by UK Prime Minister Keir Starmer and Japanese Prime Minister Sanae Takaichi, will support the construction of 5.9GW of floating offshore wind projects off the UK coast, including the Ossian, Green Volt, and Erebus projects.
The Offshore Wind Compact
The pact was signed at the highest governmental level, with Downing Street stating that the projects will support jobs across the UK and, when built, generate enough clean electricity to power 8 million homes. The statement added, "By boosting homegrown clean energy, the deal will help reduce reliance on volatile global fossil fuel markets, strengthen energy security, help get bills down for good, and make the UK Japan’s leading clean energy partner in Europe."
Project Details
Three floating offshore wind projects are central to the agreement. Below is a summary of their key characteristics:
| Project | Capacity (MW) | Location | Ownership | Key Details |
|---|---|---|---|---|
| Ossian | 3,600 | 84 km off Scotland’s east coast, water depth 72 m | Copenhagen Infrastructure Partners, SSE, and Marubeni Corp | Largest project in the pact, planned capacity 3.6GW |
| Green Volt | 560 | 80 km off Scotland’s east coast | Flotation Energy and Vårgrønn | Already received a Contract for Difference from the UK in 2024; commissioning set for 2029 |
| Erebus | 100 | Celtic Sea | Blue Gem Wind (joint venture of Simply Blue Energy and TotalEnergies) | Demonstration project; construction planned for 2026-2027 |
Japanese Involvement
All three projects have connections to Japanese firms. Marubeni Corp is a partner in Ossian. Flotation Energy, the owner of Green Volt, is a Scotland-based subsidiary of Tokyo Electric Power. Additionally, Kansai Electric Power bought a majority stake in Simply Blue Energy in October 2025, further strengthening Japanese ties to the Erebus project.
Implications for Energy Markets
By boosting domestic clean energy generation, the pact aims to reduce the UK's exposure to volatile global fossil fuel markets, according to Downing Street. The investment reinforces the UK's position as Japan's leading clean energy partner in Europe. For commodity traders and energy analysts, this signals a structural shift in the UK's power generation mix, potentially reducing long-term demand for natural gas imports used in electricity production. The floating wind technology involved also points to growing supply chain opportunities in vessels, cables, and turbine components, which may impact metals and logistics markets.
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