In the future, the world may be low carbon, but it likely won’t be low-metal. That is the conclusion reached by a recent study by the World Bank, which analyzed the demand that growth in clean and renewable energy technology would place on worldwide supplies of certain minerals and rare-earth metals. The report attempts to fill in a gap in previous analysis of climate change and global warming scenarios, which it admits “have typically paid scant attention to the metal implications necessary to realize a low/zero carbon future.” What the World Bank found is that building up clean energy technology to the levels required under the Paris Climate Agreement would likely take huge stores of a variety of rare-earth metals and other raw materials.

“As part of the transition to a low carbon economy, we are already seeing a remarkable growth in renewable energy technologies, now accounting for about 17% of global energy consumption,” writes Riccardo Puliti, head of the Energy and Extractives Practice Group at the World Bank. He is optimistic that the trend will continue. Demand for clean technology still has not reached the levels required under the agreement, however, and it is unclear what the cost of a global switch would be.

For the study, the World Bank developed commodities demand projections through 2050. These projections attempted to estimate how technological improvements in wind, solar, and energy storage batteries would make renewable energy sources more attractive in the near future. At the same time, the study acknowledges that supplies of rare-earth metals will necessarily limit the growth rate of clean energy technology.

The study examined projections for a dozen different metals, ranging from the relatively commonplace like iron, steel, and aluminum to the more rare indium, molybdenum, and lithium. All are materials used in the construction of solar photovoltaics and wind electricity generators, as well as energy storage technology.

The World Bank sees the growth of alternative energy technology, and the corresponding need for supplies of rare-earth metals, as an opportunity for resource-rich, but developing countries to grow their economies.

“With better planning, resource-rich countries can take advantage of the increased demand to foster growth and development,” said Puliti. “Countries with capacity and infrastructure to supply the minerals and metals required for cleaner technologies have a unique opportunity to grow their economies if they develop their mining sectors in a sustainable way.”

By analyzing a broad range of minerals and metals needed for clean energy production, the study shows that fears about Chinese domination of rare-earth metal production is far from universal. At present, China dominates the production of many raw materials necessary to produce batteries, solar panels, and wind generators. However, China’s natural resources do not include all necessary materials. It has no domestic platinum or palladium production, for example, two elements used in catalytic converters.

Although the study acknowledges that China has a “global dominance” specifically in supplies of rare-earth metals, it points out that growth in alternative energy technology will produce global opportunities for other mineral extraction in a variety of regions, particularly in South and Central America. In part, this reflects how little is known about the worldwide distribution of rare-earth metals. Most developing nations have not performed the necessary geologic surveys to discover these metals, which are often found mixed in with other materials.

“It is striking that aside from China, Brazil, India, and Malaysia there are no recorded production, reserve, or resource data for rare-earth metals available from any developing country regions. Although these critical metals can be found in these areas, no concerted efforts have been undertaken to accurately map their existence,” the report found.

However, even these predictions must be taken with a decent dose of skepticism. Although the study provides several different possibilities for the technology needed to sharply reduce carbon emissions in the future, the researchers acknowledge that reaching the ambitious 2050 goals relies on significant changes to both energy transmission and storage technologies. Reaching the ambitious goals of the Paris Climate Accords will require almost unforeseen levels of technological advancement and even then will only slow warming, rather than halt it.

“It is clear that meeting the Paris climate target of not exceeding 2 degrees Celsius (2°C) (and making best efforts to reach 1.5°C) global warming over this century will require a radical (that is, to the root) restructuring of energy supply and transmission systems globally,” the researchers found. At the same time, even these relatively modest gains will come at substantial materials costs.

“Furthermore, the technologies assumed to populate the clean energy shift (wind, solar, hydrogen and electricity systems) are in fact significantly MORE material intensive in their composition than current traditional fossil-fuel-based energy supply systems,” the report continued.

In this, the report acknowledges the difficulties that countries will face attempting to reach the lofty goals set by the Paris Climate Accord. Extrapolating out today’s technology predicts that demand for certain needed metals will increase dramatically. The World Bank estimates that the demand for lithium, for instance, will surge by 1,480 percent and demand for indium by 146 percent.

If demand were to reach these levels, the price of the necessary materials would doubtless become prohibitive. The details are outside of the scope of the analysis.

At the end of the day, the report is constrained by the difficulty of predicting where technology will stand thirty years from now. Today, our best predictions presume a mix of wind and solar, using new battery technology to store energy for future use. However, in the decades to come, new research could shift clean energy technology in unexpected directions. In the field of clean and green energy, there are a great many unknown unknowns.

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