Copper Shortfall Threatens U.S. Renewable Energy Transition
A study by researchers at the University of Michigan and Cornell University has found that the current rate of copper mining cannot meet the demands set by U.S. policy guidelines for transitioning the country's electricity and vehicle infrastructure to renewable energy. The paper, published by the International Energy Forum, analyzed 120 years of global data from copper mining companies and assessed the copper required to upgrade the U.S. electricity infrastructure and car fleet to renewable energy sources. The findings indicate that renewable energy's copper needs will far exceed current production capabilities.
The Inflation Reduction Act, signed into law in 2022, mandates that 100% of cars manufactured be electric vehicles by 2035. However, electric vehicles require three to five times more copper than internal combustion engine vehicles, not including the additional copper needed for electric grid upgrades. "A normal Honda Accord needs about 40 pounds of copper. The same battery electric Honda Accord needs almost 200 pounds of copper. Onshore wind turbines require about 10 tons of copper, and in offshore wind turbines, that amount can more than double," said Adam Simon, co-author of the study. "We show in the paper that the amount of copper needed is essentially impossible for mining companies to produce."
The study highlights the lengthy permitting process for new copper mines as a significant barrier. The average time from discovering a new copper deposit to obtaining a permit to build a mine is approximately 20 years. With over 100 companies mining copper across six continents, the researchers compiled global copper production data dating back to 1900 and modeled future production needs.
To meet current demands and support the developing world without considering the green energy transition, the world will need to mine 115% more copper between 2018 and 2050 than has been mined in all human history until 2018. To electrify the global vehicle fleet, as many as six new large copper mines must be brought online annually for the next several decades, with about 40% of new production required for electric vehicle-related grid upgrades.
"I'm fully on board with the energy transition. However, it needs to be done in a way that's achievable,” Simon said. The study suggests that instead of fully electrifying the U.S. vehicle fleet, a more feasible approach might focus on manufacturing hybrid vehicles. "We are hoping the study gets picked up by policymakers who should consider copper as the limiting factor for the energy transition, and to think about how copper is allocated," Simon added. "We know, for example, that a Toyota Prius actually has a slightly better impact on climate than a Tesla. Instead of producing 20 million electric vehicles in the United States and globally, 100 million battery electric vehicles each year, would it be more feasible to focus on building 20 million hybrid vehicles?"
Simon also emphasized the critical need for copper in developing countries to build infrastructure. Approximately 1 billion people lack access to electricity, 2 billion lack access to clean drinking water, and 4 billion lack access to sanitation facilities. "Renewable energy technologies, clean water, wastewater, electricity -- it cannot exist without copper. So we then end up with tension between how much copper we need to build infrastructure in less developed countries versus how much copper we need for the energy transition," Simon explained.
The study underscores that significant progress can be made to reduce emissions in the United States. However, the current emphasis on the downstream manufacture of renewable energy technologies cannot be met by the upstream mine production of copper and other metals without a complete mindset change about mining among environmental groups and policymakers.
