There are so many use cases for renewable energy, and only so many minerals available to build it.
How can the world pull more clean-energy-relevant minerals cleanly out of more spots on the planet?
Scholars grappled with the challenge at a recent Yale School of the Environment discussion.
On the evening of Feb 22nd, the inaugural Yale Energy Material Nexus conference was held at the Yale School of Environment. Students and scholars across the Yale and New Haven community gathered at Kroon Hall to hear professors, policymakers, and industry experts discuss the pivotal role critical minerals play in the global energy transition. As the world rapidly builds renewable energy infrastructure and transportation networks, the critical minerals' sourcing, processing, and trading will have profound economic, environmental, and geopolitical implications. Ensuring the critical minerals’ supply meets ever-rising demand while navigating the mineral supply chain’s impacts on the environment and society is a daunting challenge.
The conference organizers, a group of graduate student leaders in the Industrial Ecology and Green Chemistry Learning Community at the Yale School of the Environment, wanted to use the conference to bring awareness to the community and spark further discussions on understanding and addressing the challenge.
What are critical minerals?
First of all, how do we define critical minerals? Dr. Tom Graedel, Clifton R. Musser Professor Emeritus of Industrial Ecology at the Yale School of the Environment and the first keynote speaker, said a mineral is critical when "it is both essential in use and subject to the risk of supply restriction." Building on work by the National Academies, Professor Graedel developed the methodology of assessing material criticality in three dimensions: supply risk, the impact of supply restrictions, and environmental implications. The United States Geological Survey has designated a list of 50 minerals as critical, out of 81 that are non-radioactive. Professor Graedel called 21 of these critical for energy applications.
Growing mismatch in demand and supply
The global energy transition will significantly increase demand for critical minerals. Manufacturing wind turbines, batteries, and transmission lines requires a large amount and variety. Wind turbines use neodymium, praseodymium, terbium, and dysprosium. Common batteries use lithium, manganese, cobalt, and nickel. Transmission lines run on aluminum, magnesium, and silicon. Clean energy technologies also inherently require more minerals than conventional power sources. According to the International Energy Agency, "A typical electric car requires six times the mineral inputs of a conventional car, and an onshore wind plant requires nine times more mineral resources than a gas-fired plant." Since 2010, the average amount of minerals needed for a new unit of power generation capacity has increased by 50% as the share of renewables in new investment has risen." The chart below from IEA shows that the volume of minerals used for each MW of energy produced from wind and solar far exceeds fossil fuel sources. IEA estimated that “the world is currently on track for a doubling of overall mineral requirements for clean energy technologies by 2040.”
Mineral supply capacity needs to expand quickly, said speakers. Sarah Stewart, CEO of a policy research organization called Silverado Policy Accelerator, pointed out the "growing supply and demand mismatch" in the critical material market. "300 new mines need to come online in the next ten years just to serve the demand for clean technologies." said Ms. Stewart, "(and) new mines take 15-17 years to come online." The long mine development cycle translates to lagging supply increases, adding upward pressure on raw material prices and manufacturing costs of energy technologies.
The wide range of industrial applications of critical minerals exacerbates demand and supply imbalance. "There is truly a finite pot of minerals out there that are not just for clean technology applications, but many other applications, such as aerospace and defense, semiconductors or medical devices," said Ms. Stewart.
Critical minerals supply chains are also highly concentrated. China dominates many critical minerals markets, mining about 60% of the world's rare earth supply and taking a considerable share of graphite production, according to IEA. Australia and Chile produce about 70% of global lithium, while the Democratic Republic of the Congo produces the majority of global cobalt. Silverado's analysis found that Asian workers process 85% of all minerals that people dig up in the Western Hemisphere, according to Ms. Stewart. As a result, most Western countries heavily rely on imports of critical minerals. "We are leaving jobs and money on the table," said Ms. Stewart.
The highly concentrated supply of critical minerals indicates tremendous national security and geopolitical risks. "Having a single source of supply, regardless of whether or not it is your best friend or your worst adversary, is a choke point crisis waiting to happen," said Ms. Stewart.
We are leaving jobs and money on the table.
Countries should carefully consider the full implications of their policies around critical minerals to mitigate national security risks. The U.S. has taken steps to incentivize sourcing minerals domestically and from allies. For example, 40% of critical minerals used in EV batteries must be extracted and processed domestically or in a country with which the U.S. has a free trade agreement for the relevant car to prompt a $7500 credit under the Inflation Reduction Act. The percentage requirement will increase by 10% annually until it hits 80% in 2027. The IRA also introduced an advanced manufacturing production credit equal to 10% of the production cost of certain critical minerals used in advanced energy projects within the U.S.
Sourcing from political allies, in some instances, can be economically beneficial under current American policy. Abigail Hunter, Quebec Government Affairs Officer in D.C., discussed Quebec's long-standing mineral trading relationships with its Southern neighbor. "The U.S. is Quebec's largest trading partner…and the foundation of the trading relationships is based on minerals," said Ms. Hunter. For example, Quebec produces 60% of North America's aluminum, which is widely used in solar PV components, EV batteries, and overhead transmission infrastructure.
On the other hand, it is unrealistic to expect the United States and its allies to completely replace other countries’ supply, argued Dr. Saleem Ali, Blue and Gold Distinguished Professor of Energy and the Environment at the University of Delaware. He referred to this practice as "friend-shoring" and questioned its efficiency. In 2022, the U.S. domestic metal mine production was 6% lower than in 2021; the country was 100% net import reliant for 12 critical minerals and was more than 50% net import reliant for an additional 31, according to the Mineral Commodity Summaries 2023 report published by U.S. Geological Survey. On a global level, the threat of regional alliances hangs over commodity markets. An analysis by the World Trade Organization showed that splitting the world into Eastern and Western trading blocs would result in a 5% drop in global GDP.
The other drawback to friend-shoring, explained Professor Ali, is the unfair treatment of developing countries. "This approach is going to impact poorer countries disproportionately," said Professor Ali, whose family came from Pakistan.
Environmental impact and activism
Mining's soil contamination and erosion, and its contribution to deforestation and biodiversity loss, cause active opposition. Environmental activists have been leading campaigns and protests that intend to raise awareness of the environmental impact of mining and challenge the industry to scale back on mineral production. Professor Ali called this the "green paradox of criticality": minerals are needed for the clean energy transition environmentalists have called for, but at the same time, the extraction and processing of critical minerals are often vehemently opposed by them. Professor Ali argued environmental campaigns have good intentions, but the facts about environmental impacts are often muddled, especially in social media. Take deep-sea mining as an example; Professor Ali claimed that life-cycle analysis showed that deep-sea mining causes lighter impact and waste than traditional mining. However, well-funded campaigns against deep-sea mining obscured this fact.
..minerals are critically needed for the clean energy transition environmentalists have called for, but at the same time, the extraction and processing of critical minerals are often vehemently opposed by them.
Other political forces seize on anti-mining invective as a reason to attack the clean energy transition in general. Professor Ali gave another example of cobalt mining, a key element in manufacturing lithium-ion batteries for EVs. The Democratic Republic of the Congo produces about 70% of cobalt globally. In a recently published book, Cobalt Red, author Siddharth Kara revealed the horrific mining practices in Congo that exploit child labor and subject workers to hazardous working conditions. Some political conservatives have coopted the story to claim that EVs are causing harm in Congo.
Energy use in mineral processing and transportation also raises concerns among many stakeholders. Ms. Hunter used aluminum to illustrate the intensive energy toll of minerals. Nicknamed "congealed electricity," aluminum is one of the most energy-intensive metals. Mining, refining, and smelting aluminum consume 4% of global electricity. "There lies the paradox," said Ms. Hunter. "You need aluminum for clean energy technologies, but you also need clean energy technologies for aluminum."
Is recycling the solution?
How do we mitigate the geopolitical, environmental, and societal issues critical mineral production faces right now? Barbara Reck, a senior scientist at Yale researching the sustainability of material use, believes that the industry is not recycling enough to alleviate these concerns. "Recycling industry is doing well with a few major metals in products, such as steel and aluminum. However, many other critical minerals could have been recycled," said Ms. Reck. The industry realizes that much needs to be done, but the progress of R&D around recycling critical minerals is slow.
Technological innovation will also be important in reducing mineral waste and lowering the material intensity. Annick Anctil, Associate Professor in Civil & Environmental Engineering at Michigan State University, talked about how technological progress has already reduced the energy and material required in clean technologies and increased the proportion of recycled materials.
Her research on end-of-life batteries showed that 95% of these battery components are functioning and can be used to manufacture second-life batteries. Michael Hollomon, commercial director of U.S. Strategic Metals, talked about how his enterprise used proprietary hydrometallurgical processing technology for recycling. By partnering with Interco, a global recycler of lithium-ion batteries, U.S. Strategic Metals uses the technology to process "black mass" - shredded recycled batteries - and recovers more than 95% of nickel, cobalt, copper, and lithium. Holleran acknowledged there is no end-of-life battery market right now due to lack of supply, and the company's recycled batteries are only from scrapped production.
Government policies and initiatives play a key role in supporting mineral recycling at scale. The Quebec government created the "Minerals for the Future" program, working with battery recycling facilities on lithium recycling. The government is also working with Rio Tinto to run a pilot that extracts scandium from titanium tailings. Moreover, the government is targeting brownfield sites and creating an ecosystem in which battery manufacturers can repurpose the waste and byproducts. For example, the sulfur dioxide generated from battery manufacturing can be used to produce fertilizers. For Quebec, many of the production processes run on hydropower, which further reduces the carbon footprint.
However, more than recycling and innovation are needed to solve the problem. Professor Ali reminded us that 775 million people in the developing world still do not have access to electricity. "No reduction and conservation will address that - we are still going to need more metals to provide electricity access to these people," said Professor Ali. He supported the idea of an international mineral supply agreement under the United Nations or a related body.
So what is the path forward? Tough trade-offs have to be made to balance the needs of different parties. "We need to countenance some ecological impacts for the delivery of electricity and mobility that have become widely recognized as key features of human development," said Professor Ali. Nevertheless, it is up to us to decide what these trade-offs are.
Lastly, the speakers agreed that we must involve broader stakeholders and communities in the conversations. Ms. Stewart said: "it is a moment of opportunity where companies, government, community, and consumers can all benefit from policy and commercial decisions towards decarbonization, adopt less extractive methods, and create a more virtuous supply chain." The Biden administration initiated a new interagency working group across the Department of the Interior, the White House, and the Department of Energy to address different stakeholders.
Evoking the importance of stakeholder engagement, the conference was open to the public, not just the Yale community. The organizers also invited ten students from local high schools to attend and facilitated further discussions in a workshop after the session. After all, the next generation of energy leaders will face their own material issues.
You can view the full conference recording here.