Siemens AG (SIE) is working to obtain rare earths used in its wind turbines from outside China, the world’s biggest supplier, after the nation curbed production of the strategic commodities to reduce environmental damage.
Siemens, Germany’s largest engineering company, is seeking to develop supplies for rare earths in Australia, Russia, Greenland and California that will limit price increases and keep materials crucial to their products flowing, said Henrik Stiesdal, chief technology officer of Siemens Wind Power.
“It will take a longer time before Australia and the U.S. have working mines,” Stiesdal said at Siemens’s office in Brande, Denmark.
China supplies more than 90 percent of global rare earths, a group of 17 elements used in electronic technologies from hybrid cars to sonar systems. The country imposed controls on mining and exports after more than a decade of extraction depleted the resources and harmed the environment.
Siemens uses neodymium in a turbine model that’s been on sale since 2010. That technology involves “direct-drive” turbines with fewer moving parts than traditional models with gearboxes. The geared models require more maintenance and are costly to repair when used in offshore projects.
Vestas vs Siemens
Vestas Wind Systems A/S, the world’s biggest maker of wind turbines, makes geared models that contain a 10th of the quantity of rare earths used in the direct-drive machines so does not depend on the rare earths, said Finn Stroem Madsen, head of technology research at the Randers-based company.
“We will not deliver a technology to our customers which depends on a strategic raw material, and one example of that could be rare earth material,” Stroem Madsen said. Vestas is developing a 7-megawatt machine that along with some of its other models will use neodymium in its generator.
Siemens’s gearless machine links the blade to the generator directly so they spin at the same pace. This requires more magnets made of compounds using neodymium, iron and boron.
“Further than that we’re developing a variant that doesn’t use rare earth magnets at all,” said Stiesdal.
The Munich-based company purchases magnets that require less than 1 percent of the annual capacity of rare earth production, said Torsten Wolf, a spokesman for Siemens.
It doesn’t mine rare earth metals or make the magnets that use the materials, so it’s not directly affected by China’s export quotas, he said.
Enercon GmbH, a German maker of onshore wind turbines that had a 59.2 percent share of the nation’s market last year, also makes a direct drive model. It uses non-permanent magnets made of copper to avoid dependence on rare earths, said Ruth Brand- Schock, head of the Enercon Berlin office.
Siemens, which installed 2,300 megawatts of wind power last year, this month installed a 6-megawatt prototype direct-drive machine. It will offer geared turbines through 2015 as it transitions its products to all direct-drive technology, Stiesdal said.
