Alastair Muir Wood, CEO, Wood Thilsted
The UK has set ambitious clean energy targets for 2030 as part of its commitment to achieving net zero emissions by 2050. In its Clean Power 2030 report, the National Energy System Operator (NESO) called for offshore wind to form the backbone of Great Britain’s clean energy strategy, recommending that it provides over half of the nation’s power generation by 2030 to achieve a fully clean power system. This requires expanding offshore wind capacity to 50 GW by 2030, including 5 GW from floating wind – a substantial commitment to a nascent and relatively unproven technology at scale.
Given the imperative to decarbonise energy systems in the UK, is the emphasis on floating the right approach, or is it overshadowing other viable solutions?
The UK’s Offshore Wind Landscape
By the end of 2024, the UK had surpassed 30 GW of wind generation capacity, with over 14 GW of offshore wind capacity in operation, providing more than 17% of the nation’s electricity needs.
Despite this progress, a significant gap remains in meeting the 2030 targets. The most recent Allocation Round 6 (AR6) in 2024 awarded 5.3 GW of offshore wind capacity, including 400 MW of floating wind. However, this addition is modest, especially considering AR5’s lack of successful awards. The UK must accelerate its efforts to achieve its ambitious goals.
Floating Offshore Wind: Opportunities and Challenges
Floating offshore wind enables access to deeper waters up to and beyond 100 metres, effectively covering much of the UK continental shelf, where wind speeds are typically higher and more consistent. This capability also opens up new areas for development, including projects like the Innovation and Targeted Oil and Gas (INTOG) initiative, which aims to decarbonise oil and gas infrastructure by connecting small-scale, innovative wind projects directly to these facilities. Globally, countries such as France and South Korea are incorporating floating wind into their offshore wind auctions, creating potential opportunities for the UK to export its expertise and maintain its leadership position in offshore wind. Consequently, floating wind has garnered significant attention and funding from policymakers, research institutions and government-backed innovation bodies, including its own Contacts for Difference (CfD) mechanism.
However, the widespread adoption of floating wind faces notable challenges, including higher material requirements and costs. A floating foundation for a 15 MW turbine in ~100m deep UK waters may require 5,000 to 6,000 tonnes of steel, compared to approximately 2,000 tonnes for a deepwater jacket foundation. Additionally, the supply chain for floating wind is underdeveloped, with substantial upgrades required to the UK’s port infrastructure to facilitate the assembly and deployment of floating wind farms. While floating wind’s promise is undeniable, these hurdles must be addressed to realise its full potential as a cornerstone of the UK’s clean energy future.
Learning from the Past: The Monopile Experience
In the early 2010s, there was a prevailing belief that monopile foundations would become obsolete for larger turbines in deeper waters, leading to a focus on alternative structures like jackets. The research community, backed by government supported initiatives like the Carbon Trust’s Offshore Wind Accelerator, promoted innovative foundation designs, resulting in the demonstration of the twisted jacket. Industry alignment around this narrative followed, given the UK’s extensive experience fabricating jackets for oil and gas platforms.
However, advancements in monopile design approaches, most notably through the Pile Soil Analysis (PISA) joint industry project, proved this assumption wrong. PISA demonstrated that monopiles could be optimised for larger turbines and deeper waters by refining design methods, enabling them to remain the most cost-effective foundation option in competent soils. Today, monopiles are the foundation of choice for turbines exceeding 15 MW, even in increasingly challenging environments.
This historical context underscores the risks and costs of prematurely discounting existing technologies in favour of untested alternatives. By enhancing proven approaches, such as optimising monopile designs, the UK significantly reduced the cost of energy and maintained its leadership in offshore wind. These lessons should inform current efforts, ensuring innovation is balanced with practical enhancements to proven approaches.
Deepwater Wind: A Balanced Approach
In its March 2024 Contracts for Difference for Low Carbon Electricity Generation report, the Department for Energy Security and Net Zero acknowledged the transformative role of innovative foundation solutions in unlocking the commercial viability of offshore wind in deep waters. However, the focus to date has largely centred on floating wind, leaving the potential of deepwater wind technologies underexplored.
In ~100m water depths, deepwater jacket foundations and alternative monopile options, could offer a viable, cost-effective alternative to floating, leveraging established supply chains and requiring less material than floating structures. Fixed-bottom solutions are well-suited to competent soils found on the UK continental shelf and could also drive demand for UK steel, which currently contributes only 2% of the material used in domestic offshore wind projects.
Moreover, deepwater wind technologies present an opportunity to expand the UK’s offshore wind capacity without over-reliance on floating solutions. Supporting research and development in deepwater wind technologies can provide a diversified toolkit, including floating, to address the varying conditions of offshore sites. This approach balances innovation with practicality, enabling the rapid, scalable and cost-efficient deployment of offshore wind.
Conclusion: Setting the Right Goals
The UK Government’s commitment to a clean energy future should be applauded, and floating wind undoubtedly has an important role to play. However, building supply chains and scaling floating technology will take time – time we may not have if we are to meet the 2030 targets.
The real question is not “How do we scale floating wind?” but “How do we deliver 50 GW of offshore wind by 2030?” By broadening its focus and support mechanisms to include deepwater solutions, the UK could achieve its clean energy goals faster and at a lower cost, with floating as part of a balanced portfolio.
As Sir Henry Royce once said, “Take the best that exists and make it better. When it does not exist, design it.” For UK offshore wind, it’s time to take this advice to heart.
Alastair Muir Wood
Alastair Muir Wood is the Founder and CEO of Wood Thilsted, a global leader in offshore wind engineering. With over a decade of expertise in geotechnical engineering, Alastair co-founded Wood Thilsted in 2015 to revolutionise offshore wind design, delivering innovative solutions that accelerate the transition to renewable energy.
Wood Thilsted
Wood Thilsted is a specialised offshore wind engineering consultancy at the forefront of designing the global energy transition.
Driven by a shared purpose to accelerate the green energy transition, its team of world-class engineers delivers innovative, sustainable and optimised solutions that empower clients to achieve their renewable energy goals with greater speed and efficiency.
As a Certified B Corp, the company continues to push the boundaries of what it means to be a responsible business in the renewable energy industry.
For more information, visit www.woodthilsted.com/