Unlocking Offshore Wind Repowering for 2030 Delivery

Repowering mature offshore wind sites can deliver additional clean electricity within this decade without the need for new seabed allocation. Modelling of five United Kingdom offshore sites shows that repowering can provide around 915 megawatts of extra capacity and 3.76 terawatt hours of electricity every year. This volume of clean power can prevent 643000 tons (approx.) of carbon dioxide equivalent emissions each year. We show that the repowering project is socially beneficial at £73 per megawatt hour, but investor outcomes are negative in most simulations. This brief sets out the actions that can make repowering investable in the United Kingdom and repeatable in other offshore markets.

The international community is now examining actions to advance the transition to clean power by 2030. Repowering uses existing sites and grid connections, which reduces delays. The United Kingdom is a mature offshore wind market so lessons from this work can inform countries that are approaching a first repowering cycle.

Key Evidence from the United Kingdom Case Study

• Additional offshore wind capacity of about 915 megawatts from a small group of existing sites.
• Additional electricity generation of about 3.76 terawatt hours every year.
• Avoid emissions of about 643000 tons of carbon dioxide equivalent every year.
• Improvement in capacity factor from about 31.20 percent to about 42.24 percent.
• Socially positive project value at £73 for every megawatt hour of electricity produced.
• Investor simulations show an 87 percent probability of a negative net present value which indicates the need for policy action.

Policy Recommendations

United Kingdom National Actions

1. Create a dedicated repowering route in planning and marine licensing so that life extension and turbine replacement at existing offshore wind sites can proceed more quickly.
2. Adapt Contracts for Difference to address repowering projects, for example by setting separate allocations and by recognizing shorter remaining asset lives.
3. Align rules for decommissioning and for reuse of infrastructure, including options that are consistent with a circular economy for retaining sound foundations, cables and grid connections, so that these assets can be used again and developers can post proportionate decommissioning security, improving the economics of repowering projects.
4. Use public climate and infrastructure finance from national investment bodies or through green instruments to reduce risk for first repowering projects where private net present value is often negative.
5. Coordinate repowering schedules with upgrades to the electricity grid ports and installation capacity so that larger turbines can be installed without delay.
6. Include employment supply chain and community outcomes in repowering competitions so that coastal and regional areas gain predictable work.
7. Support innovation and better use of data for repowering, including condition monitoring remote inspection and digital design that can cut costs while protecting the environment.

International Actions

1. Recognize offshore wind repowering as an option that helps deliver 2030 targets and include this option in national contributions.
2. Prepare guidance on auction and tariff design that makes repowering investable and share this through multilateral organizations.
3. Support joint research and demonstration projects on offshore life extension, environmental baseline and component replacement to shorten learning times for emerging markets.
4. Encourage collaboration on installation vessels, larger turbines, and circular use of turbine materials so that countries with smaller project pipelines can achieve lower costs.
5. Share approaches for updating licenses and environmental approvals when a developer is upgrading an existing site rather than creating a new site.
6. Connect repowering with sustainable development goals by encouraging policies that protect energy access, support reskilling of the offshore workforce and provide benefits to coastal communities.

Contact and Provenance

Prepared by the University of Birmingham for presentation in the context of COP 30. The brief draws on 2025 modelling work on offshore wind repowering in the United Kingdom and is intended for policy makers energy regulators and international partners.

We would like to acknowledge and thank BISCA for their support and funding of this research project.