By: 2022 DC Fellow Hanny Rivera
Electric vehicles will be critical for meeting global greenhouse gas emissions reduction targets, yet mining for the metals their manufacturing requires is carbon intensive and environmentally harmful. But, it doesn’t all have to be. What if the lithium, cobalt, manganese, nickel, copper, graphite, chromium, and other critical minerals in your car didn’t come from unearthing tons and tons of rocks and heaping harmful chemicals on them, but instead came from seawater, your old laptop, old mine tailings, contaminated soil, or even coal, delivered by tiny microbes?
To reach net zero goals by midcentury, in 2030 the global EV stock needs to reach roughly 245 million vehicles, about 30 times more than there were in 2020. For such volumes, the industry will need roughly 30 times the amount of cobalt, nickel, and lithium. Not to mention all the other rare earth elements that are required for all the car’s electronic components. In the near future, it will also require more metals to make each car, as batteries increase in size to meet the demand for a longer driving range. While changes in battery chemistry may reduce the amounts of certain metals, such as cobalt, that are needed, the demand is still expected still outstrip supply. The extraction of all those additional metals will likely be more energy and carbon-intensive than it has been. Why? We’ve started to run out of the easy-to-extract stuff, especially for the rarer minerals. Though even common metals, like copper, now require nearly twice as much excavation for the same yield. Future mining will mean processing even more material to obtain the same amount of output.
To make matters worse both the availability of many of these minerals as well as the infrastructure to process them is highly concentrated in only a handful of countries. For example, Australia, Chile, China, and Argentina are the four largest global producers of lithium. China in particular has a stronghold on both rare earth element extraction, producing over 60% of global raw material, and owning about 85% of the global processing infrastructure. Such localized extraction and processing can cause severe supply chain constraints, as the COVID-19 pandemic has shown. Changing mining practices is therefore not only a matter of sustainability but also one of energy independence, national security, and supply chain resilience.
However, we could avoid mining in some cases and mine more cleanly when we do. Metals can be recovered from used batteries and e-waste through recycling approaches, which alone can provide access to more than 10% of the expected needs in most metals and minerals. E-waste metals are roughly 10 times more concentrated than in natural ores, and accessing these have the added benefit of preventing hazardous metals from harming human and environmental health. In addition, billions of dollars worth of critical minerals are laying in waste ore or mine tailings (contaminated water from mining activities that is held in ponds on mine sites) in Canada alone. New extraction techniques can make mining practices cleaner, more efficient, and less environmentally impactful. One of the more promising avenues for the cleaner extraction of critical minerals is through the use of biological organisms to accumulate or extract the minerals of interest in a less harmful way than current methods of recycling or remediation.
There are scores of microbes known to act on metal ores, with biological proteins capable of binding various important elements. For instance, fungi, yeast, and bacteria can leach lithium from rock ores and accumulate it within their cells. Heat-tolerant archaea (a type of microbe) can be used to extract copper effectively from ore and with lesser impacts compared to traditional methods. Rock-loving bacteria can accumulate cobalt and communities of bacteria and archaea can recover cobalt from mine tailings. Some fungal and bacterial species have been found to biologically bind tellurium, which is used in semiconductors and solar cells. Other species have also been found to bind lanthanide elements, such as terbium, which are needed for most electronic applications. And various species of bacteria can leach cerium, neodymium, lanthanum, thulium, lutetium, and terbium, even in microgravity. Some bacteria can even extract neodymium, a rare earth element from coal!
Biology has already figured out how to bind to many of the critical minerals that we need to sustain a transition to clean energy and clean transportation. We should take advantage of biology to avoid more harmful mining practices. Using synthetic biology techniques, we can further enhance nature’s naturally occurring metal-binding organisms and find ways to supercharge their powers. For instance, we can use genetic engineering to alter their DNA to improve the binding efficiency of their proteins for desired metals. We can also put the DNA encoding metal-binding proteins into other microbes that can be grown more easily and more quickly.
While biomining in this way won’t be able to replace traditional mining entirely — it is simply too new to meet the required scale — it can lead us to a different future. A future where mining impacts are limited and the elements that have already been extracted are continuously reused. A future that allows us to mine less while also keeping harmful waste out of communities. Biomining still needs to develop further, but reaching its full potential will allow us to achieve an even cleaner future. Synthetic biology has already transformed how we take care of our own health and it can transform how we take care of our planet.
About the author
Hanny Rivera was previously an AAAS Science and Technology Policy Fellow in the U.S. Department of Energy’s Water Power Technologies Office. She is now an Associate Director for Business Development at Ginkgo Bioworks, where she seeks new ways to use synthetic biology for energy and sustainability applications. She holds a B.A. in Evolutionary Biology from Harvard University, and a Ph.D. in Biological Oceanography from MIT, where her research studied genetic and physiological responses of corals under warming temperatures. She is passionate about using biology to build a more sustainable future. The views expressed in this article are solely the author’s and do not represent the people, institutions, or organizations that the author may be associated with.
