Tuesday, April 5, 2011

Clean Energy's Dirty Secret

Dysprosium Chips
Time Magazine's article Got Yttrium? was a revelation to me on the environmental cost of modern technology and "clean energy".  It turns out that rare-earth minerals are "key ingredients in electronics."  Dysprosium, neodynium, praseodynium, samarium and terbium all go into you iPod.  That sentence is enough to drive me back to learning the Latin names of plants.

While they are frequently used in tiny amounts, in fiber optics, energy-efficient bulbs and TVs, a Chevy Volt uses seven pound of rare earth magnets.  Each wind turbine uses 660 pounds of neodynium.  Dysprosium (Latin for "hard to get") has gone from $6.50 to $130 per pound over 8 years.  About 100 tonnes of dysprosium are produced worldwide each year,[16] with 99% of that total produced in China

The problem is that rare-earth minerals... are rare!   By this they mean that "they are not often found in concentrations that are economically worth mining. "  Prices have skyrocketed as the need for them increased.

Mining rare earth minerals is a messy business.  Large amounts of toxic acids are used in the refining process.  The Molycorp mine in Mountain Pass, California, in the 1990s was producing "hundreds of gallons of waste water and hour, mixed with radioactive elements from the thorium and uranium that are ofter found with rare earths."  Tightening environmental regulations made it no longer profitable and it was closed.

Meanwhile, China had become the center of rare earth mining because it didn't have the environmental and work place safety restrictions like we have in the US.  As China is becoming more aware of the environmental hazards, the price went up and the US is back in the game.  Molycorp has reopened the mine using new technology which will require only 10% of the previous waste water and will recycle that to produce the acid and alkali required in the refining process.

I would recommend you read Got Yttrium? to understand the price we will pay for having clean energy.  It is an import important step and a necessary expense for the health of the planet.  Like your daddy said,  there is no free lunch.

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