SeaTwirl S1

SeaTwirl S1 Wind Farm Profile

Overview

SeaTwirl's S1 is a pioneering project in the field of floating offshore wind energy, utilizing SeaTwirl's unique vertical-axis wind turbine design. Here is a detailed profile of the SeaTwirl S1 wind farm:

Design and Technology

• Vertical-Axis Turbine: The S1 features a vertical-axis wind turbine, which is designed from the start for the deep-water offshore environment. This design integrates the tower and the SPAR (a buoyant structure) into one rotating unit, providing a low center of gravity and enhancing stability.
• Components: The turbine consists of three main parts: the SPAR for buoyancy and stability, the Generator house where the rotation motion is converted to electricity, and the Turbine itself which transforms wind energy into rotating motion.

Robustness and Maintenance

• Robustness: The design is robust and capable of withstanding strong winds and waves, making it suitable for harsh marine environments.
• Easy Maintenance: Parts requiring maintenance are located inside the Generator housing, which is easily accessible right above water level and below the wind turbine. This accessibility reduces maintenance costs and allows for the use of locally available vessels.

Installation and Deployment

• Deployment: The S1 was deployed off the coast of Lysekil in July 2015. It has been connected to the grid and has been tested according to plan since its deployment.
• Assembly and Installation: The assembly of the turbine onto the floating substructure can take place at a port using an onshore crane or a port-side jack-up vessel. However, the large draft of the substructure may require deep-water locations or the use of floating installation vessels, which can add to the costs.

Performance and Energy Generation

• Capacity: The S1 is a 30kW floating wind turbine, which is a smaller scale compared to larger commercial turbines but serves as a proof of concept for SeaTwirl's technology.
• Scalability: While the S1 is a smaller unit, SeaTwirl's design is flexible and scalable. For example, analyses have been conducted on wind farm layouts comprising 25 10MW vertical axis turbines using SeaTwirl's design, indicating the potential for larger-scale deployments.

Market and Applications

• Niche Markets: SeaTwirl's turbines are identified for use in niche markets such as oil and gas platforms, islands, remote seaside villages, wind farms, and fish farms, where they can replace diesel generators and reduce CO2 emissions.
• Market Growth: The floating offshore wind market is projected to grow significantly, with annual growth rates estimated at over 40% from the end of the 2020s.

Challenges and Considerations

• Levelised Cost of Energy (LCOE): Vertical axis wind turbines, like those used in the S1, have historically had higher LCOE compared to horizontal axis turbines due to lower coefficients of performance. However, SeaTwirl's design aims to mitigate some of these challenges through its integrated and robust structure.
• Mooring and Stability: The floating substructure requires a robust mooring system to ensure stability and continuous operation under various environmental conditions.

Conclusion

The SeaTwirl S1 wind farm represents a significant step in the development of floating offshore wind technology, particularly with its vertical-axis turbine design. Its robustness, ease of maintenance, and scalability make it a promising solution for harnessing wind energy in deep-water offshore environments. As the technology continues to evolve, it is poised to play a crucial role in the transition to renewable energy sources.