Yesterday’s post about fake and real Christmas trees and menorahs developed out of several conversations during the holidays, but was precipitated by an article in The New York Times about the use of so-called rare earth elements in the manufacture of clean energy components. Cradle to cradle design would suggest that all materials used in consumer products ought to be capable of serving some function once the original purpose of the object has long passed. This design philosophy necessitates making components for consumer goods out of materials that can return to the ecosystem with toxification of the soils, water, or atmosphere.

Consider the plight of compact fluorescent light bulbs (CFLs). They provide efficiency several times greater than incandescent light bulbs, yet they rely on a toxic heavy metal – mercury. Now, burning coal to generate electricity also generates mercury and other toxins that degrade the environment around power plants, as well as hundreds of miles/kilometers away (as seen in acid rain). Making products more efficient is great. However, those consumer items cannot be toxic themselves.

The aforementioned New York Times article discusses the fact that “Some of the greenest technologies of the age, from electric cars to efficient light bulbs to very large wind turbines, are made possible by an unusual group of elements called rare earths.” The image at the top of this post shows these elements at the bottom of the table in light yellow. They include Terbium, Europium, and Einsteinium, among others. The article goes on to state that “These elements come almost entirely from China, from some of the most environmentally damaging mines in the country.”

In order to access these materials, “Miners scrape off the topsoil and shovel golden-flecked clay into dirt pits, using acids to extract the rare earths. The acids ultimately wash into streams and rivers, destroying rice paddies and fish farms and tainting water supplies.” The reason the elements are sought after, is that “Tiny quantities of dysprosium can make magnets in electric motors lighter by 90 percent, while terbium can help cut the electricity usage of lights by 80 percent.”

Fortunately, The Times reports that

“Multinational corporations are starting to review their dependence on heavy rare earths.[Furthermore] Osram, [featured in a recent post on efficient lighting,] a large lighting manufacturer that is part of Siemens of Germany, said it used the lowest feasible amount of rare earths. The biggest user of heavy rare earths in the years ahead could be large wind turbines, which need much lighter magnets for the five-ton generators at the top of ever-taller towers. Vestas, a Danish company that has become the world’s biggest wind turbine manufacturer, said that prototypes for its next generation used dysprosium, and that the company was studying the sustainability of the supply. Goldwind, the biggest Chinese turbine maker, has switched from conventional magnets to rare-earth magnets.”

Much like the dependence on silicon for photovoltaic panels, the dependence on finite elements may provide the greatest obstacle to clean energy. To bring back the cradle to cradle idea of design, materials that are plentiful and renewable – in addition to managed sustainably – must be the source of a regenerative, clean energy economy.

- Eric Wilson

[image source: Atomic Math]