`Green' energy alarm sounds

Sunday Age
Sunday 27/12/2009 Page: 16

SOME, of the greenest technologies of our time - - from electric cars to efficient light bulbs to large wind turbines - are made possible by a group of unusual elements called rare earths. The world's dependence on these substances is rising fast. Just one problem - these elements come almost entirely from some of China's most environmentally damaging mines, in an industry dominated by criminal gangs. Western capitals are suddenly worried about China's near monopoly, which gives it a potential stranglehold on technologies of the future. In Washington, Congress has just ordered a study of potential alternatives to the Chinese rare earth materials that are crucial to the US military.

In Guyun Village, a small community in south-eastern China fringed by lush bamboo groves and banana trees, the environmental damage can be seen in the red-brown scars of barren clay where emerald rice fields once grew. Miners scrape off the topsoil and shovel golden-flecked clay into dirt pits, using acids to extract the rare earths. The acids wash into streams and rivers, destroying rice paddies and tainting water supplies.

There are 17 rare-earth elements, some of which, despite the name, are not particularly rare. However, two heavy rare earth elements, dysprosium and terbium, are in especially short supply, mainly because they have emerged as crucial ingredients of green energy products. Tiny quantities of dysprosium can make magnets in electric motors lighter by 90%, while terbium can help cut the electricity usage of lights by 80%. Dysprosium prices have climbed nearly sevenfold since 2003, to $53 a pound. Terbium prices quadrupled from 2003 to 2008, peaking at $407.

China mines more than 99% of the world's dysprosium and terbium. Most production comes from about 200 mines in Guangdong and in neighbouring Jiangxi province. Half the heavy rare earth mines have licenses and half are illegal. Western importers don't know where the minerals they buy have come from. "I don't know if part of that feed, internal in China, came from an illegal mine and went in a legal separator," said David Kennedy, president of Great Western Technologies in Michigan, which imports rare earths.