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Falling Lithium Prices | Earth Wise

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Lithium, the key element in the batteries that power electric cars, as well as smartphones, tablets, and laptop computers, is sometimes called white gold.  Over time, the price of the metal has gone up and up.  But recently, and surprisingly, the price of lithium has actually gone down, helping to make electric vehicles more affordable.

Over the first couple of months of this year, the price of lithium has dropped by nearly 20%.  The price of cobalt, another important component of vehicle batteries, has fallen by more than half.  Even copper, another battery material, has seen its price drop by 18%.

Many analysts predicted that prices of these commodities would stay high or even climb higher.  The reason for the decline, as well as whether it is likely to persist, is the subject of much debate.

Some experts believe that the price drops are a result of demand not being as high as expected, perhaps related to slowing sales growth of EVs in Europe and China after certain subsidies expired.  Other industry experts said that the drop was a result of new mines and processing plants providing additional supply sooner than was thought possible.

Despite the price drops, mining and processing lithium remains an extraordinarily profitable business.  It costs from $5,000 to $8,000 to produce a ton of lithium that sells for ten times that amount.  With such fat profit margins, there is no shortage of banks and investors eager to finance lithium mining and processing projects.  Such profit margins are probably not sustainable and that will likely result in more reasonable prices over time.

There is plenty of lithium in the world.  The huge demand for it is a recent phenomenon and the world is still working out how to meet that demand.

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Falling Lithium Prices Are Making Electric Cars More Affordable

Photo, posted January 9, 2023, courtesy of Phillip Pessar via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The Scourge Of Salt | Earth Wise

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Rising seas are increasing saltwater intrusion on land and rising temperatures are causing greater evaporation.   The result is mounting levels of salt in waters and in soils.

Rising sea levels cause salty ocean water to push further into river deltas.  There is already a surge in saltiness across all inhabited continents.   Seawater works its way further upstream when dams hold back water.  Pumps that remove fresh water from underground sources for irrigation and drinking supplies add to the problem.  In dry regions, irrigation systems delivering water to crops increasingly bring salt onto fields.

People add to the problem by pouring saline drainage water from mines into rivers and by using salt to de-ice roads in the winter.

A modeling study pinpointed hotspots for climate change-induced salinization in numerous locations including the U.S. Southwest, wide areas of Australia, Mexico, South Africa, Brazil, central India, northern China, and more.

Some ecosystems are adapted to saline environments but major alterations in the balance between saline and fresh water is creating growing problems for ecosystems, lake fisheries, crop growing, and even human health.

The damage caused by salt is likely to be so severe that salinization will become a major cause of environmental refugees when the land they live on can no longer sustain them. 

Salt will be a growing threat to the world’s food supplies, especially where farmers depend on artificial irrigation.  About a third of the world’s food is grown in irrigated fields, and a fifth of those fields are deemed to already be salt-contaminated.  Ultimately, only a halt to climate change will be capable of combatting the scourge of salt.

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Salt Scourge: The Dual Threat of Warming and Rising Salinity

Photo, posted June 3, 2017, courtesy of Jason Jacobs via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Sand From Mining Waste | Earth Wise

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The natural resources people use the most are air and water.  It may come as a surprise that in third place is sand.  Sand is used to make glass, computer chips, toothpaste, cosmetics, food, wine, paper, paint, plastics, and more.  It is estimated that 50 billion tons of sand are used each year.

Concrete is 10% cement, 15% water, and 75% sand.  The concrete required to build a house takes on average 200 tons of sand, a hospital uses 3,000 tons, and a mile of a highway requires 15,000 tons.

One would think that there is no shortage of sand, but we are using it up faster than the planet can make it and the extraction of sand from seas, rivers, beaches, and quarries has negative impacts on the environment and surrounding communities.  For example, removing sand leads to erosion in riverbanks, significantly increasing the risk of flooding in some places.

A potential strategy to reduce the impact of extracting sand to meet society’s growing need for is also a strategy for helping to reduce the production of mineral mining waste, which is the largest waste stream on the planet.  Mining produces between 33 and 66 billion tons of waste material each year.

A new study by researchers in Switzerland and Australia looked at the potential for using mining waste as a source of so-called ore-sand.  Sand-like material left over from mining operations could be used for many current applications for sand.  Separating and repurposing these materials before they are added to the waste stream would not only reduce the volume of waste being generated by mining operations but would also create a responsible new source of sand.

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Solution to world’s largest waste stream: Make sand

Photo, posted October 22, 2005, courtesy of Alan via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Metals In Western Water Supplies | Earth Wise

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A new study published by the University of Colorado Boulder looked at the problem of rivers being contaminated by acid rock drainage.  Rocks that include sulfide-based minerals, such as pyrite, oxidize when exposed to air and water.  The resulting chemical reaction produces sulfuric acid which, when present in water, dissolves metals like lead, cadmium, and zinc.  The recent study found that rare earth elements are also leached out of rock by this process.

Rock drainage occurs naturally throughout the western United States, but historic mines that disturbed large amounts of rocks and soil have dramatically increased this process and have led to growing downstream water pollution.  Upwards of forty percent of the headwaters of major rivers in the West are contaminated by some form of acid mine or rock drainage.

The warming climate has brought longer summers and less snow in winters.  Longer, lower stream flows make it easier for metals to leach into watersheds and concentrate the metals that would otherwise be diluted by snowmelt.

Rare earth elements are essential components of many high-tech devices such as computers, hard drives, and cell phones.  There is not a long history of studying the hazards they might represent when they enter the environment.

The study looked at the Snake River watershed in Colorado and found that increasing amounts of rare earth elements are entering Colorado water supplies.  Concentrations of rare earth elements are not ordinarily monitored and there are no water quality standards set for them.

According to the researchers, once rare earth elements get into water, they tend to stay there.  Traditional treatment processes don’t remove them.  It is a growing problem that needs to be addressed.

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Rare earth elements and old mines spell trouble for Western water supplies

Photo, posted October 27, 2007, courtesy of Dion Gillard via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio.

Metal From Plants | Earth Wise

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Large amounts of metal in soil are generally bad for plants.  But there are about 700 species of plants that thrive in metal-rich soils.  These plants don’t just tolerate minerals from soil in their bodies but actually seem to hoard them to ridiculous levels.

In areas where soils are naturally rich in nickel, typically in the tropics and Mediterranean basin, plants have either died off or have adapted to become nickel loving.  Slicing open a tree with this adaptation produces a neon blue-green sap that is actually one-quarter nickel, which is far more concentrated than the ore that typically feeds commercial nickel smelters.

A group of researchers from the University of Melbourne and other institutions is investigating whether this phenomenon is not just interesting but might also be of real commercial value.  They established a plot of land in a rural village in Borneo and have been harvesting growth from nickel-hyper accumulating plants.  Every six to twelve months, a farmer shaves off one foot of growth from these plants and either burns or squeezes the metal out.  After a short purification, they end up with about 500 pounds of nickel citrate, potentially worth thousands of dollars on international markets.

Phytomining – extracting minerals from hyper-accumulating plants – cannot fully replace traditional mining techniques.  But the technology could enable areas with toxic soils to be made productive and might allow mining companies to use plants to clean up their former mines and waste while actually collecting some revenue.

There are other plants that suck up cobalt, zinc, and similarly crucial metals.  With growing demand for metals, perhaps it is time to harvest them on the farm.

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Down on the Farm That Harvests Metal From Plants

Photo courtesy of the University of Queensland.

Earth Wise is a production of WAMC Northeast Public Radio.

WAMC Northeast Public Radio

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