Benefits of floating offshore wind

DNV predicts that, by 2050, floating offshore wind will generate 264 GW or 15% of all offshore wind energy. As part of Net-Zero goals and ambitious energy transition objectives, offshore wind projects are multiplying around the world and floating wind systems are allowing the industry to move farther offshore towards greater water depths. This blog delves into four main advantages of floating offshore wind: 

• More efficient installation and maintenance
• Less environmental impact
• Improved access to better resources
• Favourable impact on the local economy 

More efficient installation and maintenance 

One of the major cost benefits of floating wind systems is a lesser reliance on large and expensive installation vessels. 

Contrary to fixed turbines which require heavy lift vessels to install the foundations, transport and assemble the parts on-site, and erect the turbine, floating turbine platforms are assembled in port and towed to site with the help of tugs and anchor handling vessels, which can bring about significant cost savings.

Less environmental impact 

By allowing the wind turbines to be installed farther offshore, floating wind farms face less of the traditional NIMBY (“Not In My Back Yard”) resistance from local communities, since visual impact over the skyline and noise issues are minimised. 

Not only do they benefit from being “out of sight, out of mind”, but their installation is also less invasive than traditional bottom-fixed projects: 

Drag anchors, SEPLA anchors, suction piles, and other anchoring solutions minimise the need for noisy piling installation, posing less threat for fish and marine mammals. They are also easier to retrieve, should this be needed. Acteon’s long-standing track record in designing, fabricating, installing, and recovering suction piles, as well as their extensive worldwide inventory of mooring equipment make anchors, chain, rope, and other mooring kit easily available. Anchors like the SEPLA deliver the same vertical load capacity as a suction pile, while weighing four times less. Choosing such efficient anchors allows a faster installation of the mooring system, reducing the costs and the carbon footprint. 

By being farther away from the shore, they have less impact on the fragile coastal ecosystem and the landscape. They also have less impact on other marine users such as fishing, pleasure vessels, and marine transportation. 

Improved access to better resources

Not only do winds blow stronger farther offshore but they are also more consistent. Over 80% of all the offshore wind energy resource is in waters deeper than 60 meters where bottom-fixed installations are not feasible. Stronger and more consistent winds can mean that capacity factors of over 60% can be achieved for higher-depth, floating wind installations (the Hywind floating wind farm in Scotland achieved over 65% capacity factor in the first three months of operation) compared to between 45% and 60% for a fixed wind turbine in the North Sea. As a result, floating wind projects may very well lead to a better Levelised Cost of Energy (LCoE) than fixed ones.

Not only does floating wind technology allow improved access to more wind resources by moving farther offshore, but also by relying less on seabed conditions, it provides access to areas and resources normally not accessible with simply fixed foundations. For example, the offshore western coast of the United States drops off rapidly of the continental shelf and as a result, is largely impractical for fixed offshore wind. Future offshore wind development in California will likely be driven by floating projects.

Favourable impact on the local economy

As they are fully built and assembled onshore, floating wind turbines require the development of a local supply chain including specialties such as welding and assembly, electrical specialist services, heavy lifts, etc… The Port of Cromarty Firth recently secured significant government funding to expand and become the first UK port capable of manufacturing floating wind turbines at scale. The Port estimates that between 280 and 1,000 full-time equivalent (FTE) jobs will be created when the port becomes fully operational.

With the development of some ports dedicated to assembling floating offshore wind turbines, floating wind could have some serious positive impact on the regeneration of old industrial coastal areas. 

Conclusions 

The offshore wind industry is changing fast and floating wind is set to play a major role in its future. The industry is closing in on several platform designs but is still evaluating some prototypes. The resulting designs are unlikely to be a one-size-fits-all, as some may better fit local electricity demand and environmental conditions than others. Acteon leverages their domain knowledge in engineering, mooring, and marine installation to service this new and promising industry.