Critical minerals scarcity could threaten renewable energy future
The supply chains for critical and rare minerals are vulnerable to political and economic disruptions that could hamper the global shift to a renewable energy future.
As population and standards of living rise in the coming decades, finding and developing sustainable sources of the critical and rare minerals crucial for modern electronics and renewable energy technologies will be one of the “most important topics facing humanity.”
That was the consensus of experts from industry, government agencies, and academia speaking at a mineral resources conference held at Stanford University last month.
“Due to the rapidly increasing need for mineral resources as Earth’s human population continues to grow exponentially and the need to minimize the environmental and social impacts of mining, it’s essential that Stanford be involved in the field of economic geology — the study of the formation, exploration, and utilization of mineral resources,” said conference organizer Gordon Brown, the Dorrell William Kirby Professor of Geological Sciences at the university’s School of Earth, Energy & Environmental Sciences (Stanford Earth).
Critical and rare metals — which include lithium, copper, uranium, gold, and so-called rare earth elements (REEs) — are prized for their electronic and magnetic properties and play a crucial role in the production of modern electronics. They are important for everything from smartphones and batteries to advanced weapons systems.
Ravenous consumption of metals
Rare metals are especially vital for renewable energy technologies, such as electric cars and solar panels. For example, a single Tesla vehicle requires about 15 pounds, or a bowling ball’s worth, of lithium, and thin, cheap solar panels need tellurium, one of the rarest elements on Earth.
Lawrence Meinert, the acting deputy associate director of the Energy and Minerals Division of the United States Geological Survey (USGS), called humanity’s consumption of metals over the last century “truly mind-boggling.” People now use six times more iron per person than 100 years ago, which has required iron ore production to ramp up by a factor of 26.
As the human population swells to an estimated 10 billion by 2050 and standards of living in developing countries rise closer to that of Western countries, our ravenous consumption of metals will only accelerate in the coming decades.
“Technology has changed how we use resources,” Meinert said. “A couple of decades ago, building something big like the Golden Gate Bridge required large amounts of a few metals like iron and steel. But a modern smartphone uses the majority of the periodic table.”
Essential rare elements concentrated in a few countries
There is one silver lining, though, which is that modern electronics require very small amounts of critical elements. “There’s no risk of running out,” Meinert said. “The bigger risk is supply chain disruption.”
These disruptions can take many forms, including economic and political, experts say. For example, critical and rare minerals are often byproducts of much larger mineral operations such as copper, so “if copper price falls, then the production of these critical elements will also be at risk,” said Roderick Eggert, a mineral economist at the Colorado School of Mines.
Production of many essential elements is also concentrated in just a few countries, most notably China, which mines 93 percent of the world’s rare earth elements. If China’s ports were devastated by a natural disaster such as a tsunami, Meinert said, it would have grave repercussions for world trade and economies.
Having a near monopoly on crucial elements also allows countries to restrict access whenever they want. For example, when Japan detained the captain of a Chinese fishing trawler that collided with Japanese coast guard vessels in 2010, China responded by halting all shipments of rare earth elements to Japan, which the country relies on to produce hybrid cars and electronics. Japan capitulated shortly afterward and released the captain.
China exerted its influence again a few years later, Brown said, when it lowered the price of global REEs to force a U.S. company that was operating the Mountain Pass Rare Earth Mine to go bankrupt.
Importance of U.S. mineral mapping
So, what can the United States do to minimize the risks of supply disruptions of critical minerals? One idea is for the U.S. to dramatically ramp up mineral mapping projects across the nation using cutting-edge geophysical imaging tools such as LIDAR and hyperspectral imaging. “We have better maps of the geology of Afghanistan than the U.S.,” Meinert said.
If the U.S. is to embark on a nationwide geological mapping project, it should do so soon, experts say. “There is about a 12-year lag between when a [mineral deposit] is discovered and when it goes into production,” Meinert said.
The U.S. has shown before that it is willing to invest in such projects when the perceived need is great, said conference speaker Tom Benson, a recent Stanford Earth PhD alumnus who now works at Lithium Americas. “There was a huge push by the USGS and the U.S. government to look for uranium resources [important for nuclear applications] in the 1970s and 1980s,” Benson said. “That push funded a lot of the fundamental geological maps that exists today. We need that same push for critical minerals.”
A recent Nature Communications study by Benson and Gail Mahood, a professor emerita of Geological Sciences at Stanford Earth, provides a preview of what a large-scale geological mapping project could unearth. The scientists showed that clay layers at supervolcano calderas around the world, including here in the U.S., contain large lithium deposits. Benson also discovered previously unknown supervolcano calderas in the McDermitt Volcanic Field on the Oregon-Nevada border that could be future targets for lithium mining.
If the technology to affordably extract lithium from clay can be developed, it would diversify the global supply of lithium, which is currently produced mainly in Chile and Australia from non-clay sources. “Lithium clays could really transform the market in the future,” Benson said.
Reducing critical mineral waste
Technological innovation could also help reduce critical mineral waste during the production phase. “About half of the neodymium that goes into magnet materials ends up on the shop floor because that’s the nature of magnet manufacturing,” Eggert said.
Eggert also urged materials scientists and product engineers to investigate ways to further minimize the amount of critical and rare minerals required for electronics.
“Produce more. Waste less. And use less,” he said. “Those are the three fundamental things we have to do in the long term if we want to avoid supply chain disruptions.”