Countries around the world are beginning to fully unleash the potential of wind power as a key source of energy. However, among the biggest challenges for the centuries-old technology are continued improvements in reliability and efficiency. Most turbines use a series of shafts and gearboxes that are capable of converting the slow rotation speed of a wind turbine into the high rotation speed necessary for power generation. While this is effective, the method is less efficient, and the gearboxes and shafts often require maintenance.
The next generation of wind turbines, however, utilizes “direct drive” technology powered by rare earth permanent magnet generators (PMGs). Direct drive turbines produce energy even at a low rotation speeds, eliminating the need for gearboxes. The results are more efficient power production and, with the elimination of the gearbox, lower chances of mechanical failure.
The PMGs are the key, and they require hundreds of kilograms – if not tons – of neodymium (neo) magnets. Neo magnets are very well-suited for this application because of the enormous amount of magnetic power they can create relative to their size. And in the case of wind power, where rotation speeds can vary greatly, the neo magnet powered PMGs can more consistently and more efficiently generate electricity.
In most cases, the neo magnets must also have dysprosium so that the magnet will maintain its strongest magnetic properties even at high heat levels. However, some PMG wind turbines are being designed to keep the magnets cool and reduce the need for dysprosium, which is one of the rare earths in shortest supply.
By improving the efficiency and reliability of wind power, rare earth PMGs are also improving the cost-competitiveness of wind turbine technology and helping to ensure that wind power features prominently in the world’s current and future portfolio of energy sources.