Volgens dit Engelstalige artikel belemmerd een tekort aan beschikbare kritische metalen (elementen) de opschaling van allerlei alternatieve energie opwekking.
Enkele quotes uit het artikel (sorry voor het Engels):
A shortage of “rare earth” metals, used in everything from electric car batteries to solar panels to wind turbines, is hampering the growth of renewable energy technologies. Researchers are now working to find alternatives to these critical elements or better ways to recycle them.
Researchers and industry workers alike woke with a shock to the problems caused by these dodgy supply chains in 2011, when the average price of “rare earths” — including terbium and europium, used in fluorescent bulbs; and neodymium, used in the powerful magnets that help to drive wind turbines and electric engines — shot up by as much as 750 percent in a year. The problem was that China, which controlled 97 percent of global rare earth production, had clamped down on trade. A solution was brokered and the price shock faded, but the threat of future supply problems for rare earths and other so-called “critical elements” still looms.
Despite the high cost and high demand of metals critical for energy technologies, very little of this metal is recycled
Getting the metals out of modern technology is a pain, since they are incorporated in tiny amounts into increasingly-complex devices. A circa-2000 cell phone used about two dozen elements; a modern smart phone uses more than 60. “We’re making things more difficult for ourselves,” says King. Despite the relatively high concentrations of rare earths in technology, he says, it’s actually chemically easier to separate them from the surrounding material in simple rocks than in complicated phones.
These efforts, among others, have reduced China’s production share from 97 percent to about 90 percent in the past year or two
It can be difficult to develop economies of scale when dealing with materials only used in tiny amounts. Global demand for tellurium in 2009, for example, was just 200 metric tons. All of that came as a by-product from copper or gold mining. Though tellurium is extremely valuable at $145 per kilogram, the tiny amounts hardly make a blip in the profit sheets of these mining companies. “They have to be dragged into production kicking and screaming…
A final approach is to find alternative materials that don’t need so many critical elements in the first place. This is a demanding task. “The rare earths are kind of magic,” says King, in terms of their properties. They are a critical ingredient in magnets, for example, because of the way they wrangle the strong but unruly magnetic properties of iron — a task that no other element seems able to do. Research efforts attempting to make even stronger magnets without any rare earths are considered a long shot.
But for other elements, like neodymium, this can’t be the only solution. “Right now we need tiny amounts of neodymium, for the ear-buds of your smartphone,” says King. “But for a high-performance wind turbine you need about two tons.”