Saturday, June 04, 2011

The Rare-Earth Crisis - Technology Review

The Rare-Earth Crisis

Today's electric cars and wind turbines rely on a few elements that are mined almost entirely in China. Demand for these materials may soon exceed supply. Will this be China's next great economic advantage?

  • May/June 2011
  • By Katherine Bourzac

Mighty mine: This 50-acre mine on the eastern edge of California’s Mojave Desert was once the world’s leading supplier of rare-earth metals. Water pooled at the bottom of the mine while it lay idle after being shut down a decade ago. Credit: Photography by Daniel Hennessy

On the eastern edge of the Mojave Desert, an hour's drive southwest of Las Vegas in Mountain Pass, California, lies a 1.4-billion-year-old deposit of cerium, neodymium, and other metals that is the richest source of rare-earth elements in the United States. Beside hills populated by cacti, Joshua trees, and wandering tortoises is a vast waste dump of tan and white rocks that was built up over more than 50 years of production at a 50-acre open-pit mine here. The mine was once the world's biggest producer of these metals, which are crucial to such diverse products as computer hard drives, compact fluorescent light bulbs, and the magnets used in electric vehicles' motors. And the site still holds enough of them to mine for at least another 30 years. But in 2002 it was shut down, owing to severe environmental problems and the emergence of Chinese producers that supplied the metals at lower cost. The mine sat idle for a decade.

With worldwide demand for the materials exploding, the site's owner, Molycorp Minerals, restarted mining at Mountain Pass last December. It is now the Western Hemisphere's only producer of rare-earth metals and one of just a handful outside of China, which currently produces 95 percent of the world's supply. Last September, after China stopped exporting the materials to Japan for two months, countries around the world began scrambling to secure their own sources. But even without Chinese restrictions and with the revival of the California mine, worldwide supplies of some rare earths could soon fall short of demand. Of particular concern are neodymium and dysprosium, which are used to make magnets that help generate torque in the motors of electric and hybrid cars and convert torque into electricity in large wind turbines. In a report released last December, the U.S. Department of Energy estimated that widespread use of electric-drive vehicles and offshore wind farms could cause shortages of these metals by 2015.

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