Limiting the rise in global temperature to no more than 1.5 degrees Celsius requires decarbonization. This means slashing fossil fuel use, switching to renewable energy sources, and electrifying as many sectors of the economy as possible. Doing these things requires huge numbers of wind turbines, solar panels, electric vehicles, and storage batteries. All of them use rare earth elements and other critical metals.
The 17 rare earth elements are actually common, but they are called rare because they are seldom found in sufficient quantities to be extracted easily or economically.
China once supplied 97% of the world’s rare earth elements as a result of government support, cheap labor, lax environmental regulations, and low prices. Once the world started to realize the dangers of being so dependent on China, many countries began developing their own rare earth element production. (However, today China still produces 60-70% of the world’s rare earth elements).
It is difficult to mine rare earth elements without causing environmental damage. The prevalent extraction techniques involve toxic chemicals that can leach into the environment and, because rare earths are often found near radioactive elements, mining often brings dangerous radioactive waste into the environment.
Researchers are working on ways to make rare earth mining more sustainable. Some of these include biomining – which uses microbes to extract rare earths from ores, electrical methods to free rare earths from ores, and so-called agromining, which is growing plants that hyperaccumulate rare earths from the soil into their tissues.
Making rare earth mining more sustainable and less harmful to the environment is an essential part of the world’s future.
Photo, posted November 18, 2008, courtesy of the Oregon Department of Transportation via Flickr.