Permanent Magnets in Offshore Wind: State of the Art, Future Trends and Risk

This paper presents an overview, state-of-the-art, development trends and associated risks of the rare earth permanent magnets usage in the offshore wind industry. The offshore wind is set for a major growth and demand for permanent magnets is expected to rise dramatically. This study puts forward a critical analysis and brings to attention discussions with pros and cons about the rare earth element (REE) in offshore wind. It also highlights the risks associated with REE permanent magnets including: a large increase in demand; concentration of supply chain; environmental hazards; market volatility and high prices; specialized workforce; constraints linked to patents; role of national policies, acts and international policies; and availability concerns. Moreover, it presents innovative technologies to reduce or substitute REE in magnet, although challenging to achieve similar performance characteristics. At the system level, use of hybrid system can also contribute significantly to lighter generator and thus REE reduction.