Global Developments in Floating Offshore Wind

By Prof Lars Johanning, University of Exeter and Programme Lead for Marine-i

Floating Offshore Wind (FLOW) has huge long-term potential to deliver cost-effective renewable energy at scale. FLOW offers the scope to site wind farms in much deeper waters and with access to more powerful wind resources. Around the world, governments and businesses are racing to solve some of the key challenges that will need to be met in order to grasp this important opportunity.

These challenges include:

·       Refining the optimum designs for moorings, blades and turbines

·       Installing and operating in harsher and more dangerous sea conditions

·       Constructing and laying power cables in deeper waters and over longer distances

·       Setting up the necessary port facilities for the construction of turbines

·       Putting in place the support services needed for operations and maintenance

·       Developing robust commercial models to attract long term investment

The UK is already a global leader in FLOW development and deployment, with the Hywind project in Scotland being the world’s first commercial windfarm to use FLOW technology. Marine-i is now playing a leading role supporting innovation creation towards a major FLOW wind farm in the Celtic Sea. Celtic FLOW intends to deliver the world’s first 500MW FLOW farm. You can read further details on this project on our News pages

Looking beyond the UK, there are a number of important developments taking place around the globe that will help accelerate worldwide uptake of this new technology. Here is a selection of these projects:

Portugal: WindFloat Atlantic is a 25MW FLOW array that is under construction off the Portuguese coast and has already delivered its first power. It is built on three semi-submersible platforms and does not require heavy-lift construction vessels, which is an important cost saving. Once fully operational, WindFloat could provide enough power for 60,000 homes.

Spain: W2Power is the world’s first FLOW turbine to feature two rotors. Spanish company EnerOcean claims that the solution also offers reduced costs, compared to floating foundations or traditional fixed foundations, due the materials used in its construction. A 1:6 scale version of W2Power is currently being tested off the coast of Gran Canaria.

In a separate development in Spain, a prototype of SATH (Swing Around Twin Hull) is being trialled in open seas off Santander. This design is based cylindrical pre-stressed concrete hulls anchored to the seabed via a single-point mooring system. This allows the system to move freely to face the wind.

Sweden: SeaTwirl is a unique,  vertical-axis design which rotates as one unit, down the length of its axle. This powers a direct-drive permanent-magnet generator. The SeaTwirl design uses the seawater itself as a roller bearing and stores energy in a water-filled torus. Its makers claim that its simple, robust design has a minimum of breakable moving parts, which means less downtime and more output. The design also provides easy access to parts requiring maintenance. As well as planning a new flagship site off the coast of Norway, SeaTwirl is also actively targeting new offshore developments in Brazil.

Denmark: Stiesdal Offshore Technologies’ innovative TetraSpar is set for prototype testing off Norway during 2020. The design is based on a tubular steel main structure with a suspended keel that will be moored to the seabed by three anchor lines. Due to this design, it can be fabricated at quayside, reducing the cost of both materials and assembly.

South Korea: Equinor, Korea National Oil Corporation and the Korean power company Korea East-West Power have formed a consortium to develop a 200MW floating wind farm off Ulsan in South Korea. Following an initial feasibility study, the plan is to start construction in 2022, with possible power production start-up in 2024.

Japan: The Japan Wind Energy Association claims that 18 GW of floating wind turbines could be installed in that country by 2050. Japan has been operating a demonstration scale FLOW project off the coast of Fukushima since 2015. The country sees FLOW as a vital part of its future energy supply requirements.

USA: The USA has seven high-profile FLOW projects in development, as it seeks to accelerate its exploitation of the technology. One of the most ambitious is Castle Wind’s plan to build a 1,000 MW FLOW wind farm at Morro Bay off of California’s central coast. If successful, this will consist of approximately 100 FLOW systems situated 30 miles offshore in order to take advantage of consistent wind resources. The company believes this would play a crucial role in helping the state achieve its goal of 100% emissions-free energy by 2045.

The examples above give some impression of the scope, scale and pace of development that is taking place in Floating Offshore Wind. No wonder that some analysts are forecasting a 50% annual growth rate for the FLOW market over the next five years.

FLOW represents a massive opportunity for marine tech businesses and innovators right across the supply chain. As well as opportunities related to FLOW in the Celtic Sea, the global market potential is immense.

If your business needs help with its RD&I in order to develop FLOW-related product or service ideas, contact the team at Marine-i and let us share our knowledge and expertise with you, to help you take it forward to commercialisation.