IF THE unofficial rallying cry of the fossil fuel lobby is “drill, baby, drill”, renewable energy should have one too: “dig, baby, dig”. If we are going to hit our climate targets, the world is going to need a lot of new mines.
“Minerals are essential ingredients of the future clean energy system,” says Fatih Birol, executive director of the International Energy Agency (IEA). “If we try to visualise our future clean energy systems – millions of electric vehicles, cars, buses, windmills, solar panels – they need minerals to build. Huge amounts of minerals.”
He isn’t exaggerating. According to a , if the world is to reach its target of net-zero carbon emissions by 2050, overall demand for what it calls “critical minerals” – including lithium, copper, cobalt, nickel and the rare earth elements, all of them vital ingredients of clean energy tech – will increase sixfold. Another recent estimate from Japan’s National Institute for Environmental Studies forecasts that electrifying transport and expanding renewable power generation will .
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That presents a huge challenge to the realisation of our clean energy dreams. While there is no shortage of the minerals themselves, getting them out of the ground in time, in sufficient quantities, and without creating another environmental monster, is a different matter. Ultimately, we have no choice. “We need to do it,” says Kingsmill Bond, a strategist at energy think tank . “But we need to do it the very best way we can, so that we don’t trash the planet again.”
Mining is already a blot on Earth’s landscape, albeit a necessary one. According to , UK, even though mining technology has improved immeasurably over the course of human history, 99 per cent of all metal mining still , often after removing vast amounts of overlying rock. The ore must then be processed, creating an enormous quantity of waste – about 100 billion tonnes a year, . Mineral extraction and processing consumes a lot of energy, and the mining industry is one of the single-biggest emitters of greenhouse gases. In 2018, its , about 10 per cent of total human-generated greenhouse gas emissions.
Mining also has well-documented environmental and social costs. One recent study of mineral extraction in the Brazilian Amazon found that the environmental impact of a single mine can . That isn’t just a question of the toxic waste that is often produced, but stuff like roads for moving materials. “It’s the infrastructure associated with the project,” says study leader Laura Sonter at the University of Queensland in Brisbane, Australia, plus the secondary pressures as people come to live and work there and other industries spring up.
All of this gives pause for thought as the world seeks to wean itself off fossil fuels. Like-for-like, clean energy technologies require vastly more minerals than their dirty counterparts, as components of batteries, wind turbines, solar panels and electricity transmission and distribution lines. According to IEA figures, an electric car requires six times more minerals, excluding steel and aluminium, than a petrol one, and an offshore wind plant 13 times more than a gas-fired power plant of equal capacity. The growth of renewables means that it already takes 50 per cent more minerals to generate a unit of electricity than it did in 2010. For some minerals, growth in demand will be an order of magnitude higher.
For the IEA, the principal concern surrounding these critical metals is keeping the lights on, the issue that has energised the agency since it was formed after the oil crisis of the 1970s. It sees possible darkness ahead – because of a looming mismatch between mineral demand and supply. “We are expecting some huge demand increase for many of the minerals vital for the energy transition,” says IEA analyst Tae-Yoon Kim. “This could make the energy transition either more expensive or delayed.”
Already, this year has seen steep price rises for some essential minerals and metals. At the time of writing, lithium had roughly trebled in price and cobalt had risen by about 60 per cent. Copper, which the IEA describes as “a cornerstone for all electricity-related technologies”, with uses in power lines, batteries, solar panels and more besides, was up by about 25 per cent because of a lack of sufficient high-quality deposits. Battery-grade nickel, too, is in short supply, and there are also concerns around the rare earth metals.
That isn’t a symptom of insufficient known reserves we could extract now, says Bond. “We have in the Earth’s crust between dozens and hundreds of years of supply of the minerals required.” The problem, says Kim, is that mining companies aren’t yet sure that grand ambitions for a climate transition will be realised, and so are nervous of making the large investments needed to mine these reserves. Governments need to start sending stronger market signals to the mining industry that the energy transition is go, he says.
“Demand for critical minerals is set to increase by a factor of six”
According to the IEA, the average length of time it takes to convert a known mineral deposit into a productive mine is 16.5 years. The first decade or so of that is planning and feasibility studies, and then it takes another four or five years to dig the mine and build the infrastructure. There is some scope to reduce the planning phase, but there will still be a squeeze on supply in the coming decades.
Even then, “dig, baby, dig” isn’t the answer to energy security. Many known mineral deposits are concentrated in a handful of countries, sometimes quite unstable ones. Most of the world’s cobalt is in the Democratic Republic of the Congo (DRC), much of the lithium in Bolivia and Chile, battery-grade nickel is concentrated in Indonesia and 60 per cent of rare earth production takes place in China. “That is a concern from a geopolitical point of view,” says Kim. Trade disputes or natural disasters in important producing countries can have a major effect on global supply and prices. “Scaling up of supplies from diversified sources is quite crucial,” says Kim. To that end, governments should step up their geological survey work to find new deposits, he says. From what we know now, Australia, Canada, Chile, the DRC, Indonesia, Peru and the US could be the big winners of a green mineral boom.
The worry expressed in many quarters is that in our rush to extract these minerals, we risk cancelling out the environmental gains of the clean energy transition. In some cases, concerns about environmental sustainability are already a barrier to filling supply holes. With nickel from Indonesia, for example, much of it is under areas in or close to national parks or other protected areas.
There is no reason, however, to think that overall the green minerals boom will spawn an environmental problem equivalent to the one it aims to solve, says Bond. “You’ve got to think about the scale,” he says. Our current energy system requires us to harvest and process 13 billion tonnes of fossil fuels a year, he says. The equivalent figure for critical minerals is 43 million tonnes. “It’s 300 times less stuff,” says Bond. “It just stands to reason that it’s going to have a smaller environmental impact.”
In terms of greenhouse gas emissions, that case is unarguable, says , another IEA analyst. Across its lifetime, an electric car produces half the emissions of a petrol one, even accounting for those associated with mining and processing the lithium, cobalt and nickel in its battery. If the battery is recharged from renewable sources of electricity, that footprint halves again. The same is broadly true of other green energy technologies.
And unlike fossil fuels, which once burned stay burned, mineral resources can be reused, in many cases potentially hundreds of times. With better recycling of, say, cobalt and nickel from dead car batteries, mining intensity ought to fall over time. Whether this can happen is an open question. “Recycling is quite well established for bulk metals such as steel, aluminium and copper, but that’s not yet the case for others such as lithium and rare earth elements,” says . “That will have to change.”
The IEA estimates that between 2030 and 2040, the amount of recycled minerals in the supply chain – mostly copper, cobalt, nickel and lithium from spent batteries – will need to increase from around 100,000 tonnes a year to 1.2 million tonnes, about 10 per cent of total demand. Most importantly, that will require economies of scale to make recycling viable, says Kim. To that end, manufacturers need to design products that are more easily recyclable, and politicians need to encourage more efficient waste collection and sorting, he says.
“Mining is already our single biggest source of waste”
Kim also sees a role for innovation. When rising demand for photovoltaics pushed up demand for silver and silicon, manufacturers responded by reducing the quantity of both required in a solar panel. There are probably similar efficiency gains to be squeezed out elsewhere, as well as scope to substitute one mineral for another, especially among the rare earth metals, a group of 17 elements that share many physical and chemical characteristics.
But greenhouse gas emissions aren’t the only existential environmental crisis facing humanity. The UN recognises two others – the destruction of biodiversity, and waste and pollution. On both these fronts, mining doesn’t get such a clean bill of health.
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Earlier this year, a team at the Vienna University of Economics and Business in Austria published an analysis of the . It looked at nine metal ores: bauxite (a source of aluminium and gallium) and those of copper, gold, iron, lead, manganese, nickel, silver and zinc. The extraction of all of these, except lead, has boomed in the past two decades. In 2019, 79 per cent of the ore extracted originated from five of the six most species-rich of Earth’s biomes: deserts and dry shrublands; tropical and subtropical moist broadleaf forests; temperate broadleaf and mixed forests; montane grasslands and shrublands; and tropical and subtropical grasslands, savannas and shrublands. Since 2000, extraction from the most species-rich biome of all, tropical and subtropical moist broadleaf forests, has more than doubled, due largely to expansion in New Guinea, India and Indonesia.
The team also found that half of the world’s metal mines are 20 kilometres or less from protected areas – recall that a mine’s footprint can have a radius of 70 kilometres. And 8 per cent of global production of the metals it looked at in 2019, amounting to 480 million tonnes, was mined within protected areas. The researchers didn’t directly link mining activity to environmental damage, but there is ample evidence of that from case studies, says team member .
Waste is part of that picture. Mining is already the single biggest source of anthropogenic waste, largely in the form of rock removed to get at ores. The associated problems are well documented. Poorly maintained tailings dams are a particular issue. These are dams, often themselves built up from waste rock from mining, used to contain mining by-products. Frequently, they fail, sometimes spreading toxic slurry over a wide area. The Cobriza tailings dam failure in Peru in 2019, for example, released 67,000 cubic metres of cyanide-laced copper waste into the Mantaro river. Such collapses can also kill large numbers of people; another 2019 disaster at Feijäo in Brazil unleashed a mudslide that killed at least 237.
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One mine causing particular concern at the moment is the Grasberg copper and gold mine in Papua, Indonesia. One of the world’s largest mining projects, it sits right next to the largest national park in South-East Asia, Lorentz National Park, which is home to outstanding biodiversity and a range of important ecosystems. The mine has been .
Again, a minerals boom is only going to intensify such pressures. In 2020, a team led by Sonter totted up the , but also future prospective mines. It gathered information on all of the world’s documented mines, of which there are more than 62,000, including about 45,000 in development. The team found that these would collectively affect an area of up to 50 million square kilometres, more than a third of all land, excluding Antarctica. That assumes that mining sites have an impact on biodiversity extending 50 kilometres in all directions, .
The team also found that 31 per cent of this land is in areas designated as important for halting biodiversity loss, with 8 per cent formally protected. One in seven protected areas has a current or future mine in it, or near enough for its effects to be felt. Over 80 per cent of the mines, both active and planned, do or will produce minerals crucial for the energy transition. “I think it will be really challenging to achieve the energy transition without creating another huge environmental problem,” says Giljum.
Sonter’s analysis is just a rough indicator of where mines might be in the future, however. “There’s a lot of exploration and prospecting in places that will never be developed for a number of reasons – it might be economic, or it could come down to environmental factors,” she says. Analyses such as hers can be used to aid decisions on where to site mines, so as to limit their impact in areas important for biodiversity conservation. “There is a lot of opportunity for us to strategically invest in mining outside of these conservation areas,” she says.
But international bodies seem to be behind the curve: new mines aren’t explicitly acknowledged as a threat in the . “Mining isn’t mentioned at all,” says Sonter. “I’m constantly shocked that agriculture and forestry get mentioned specifically, and mining is just kind of pushed to the side.”
A spokesperson for the UN acknowledges that mining and mineral processing aren’t expressly mentioned, but points out that they are covered by many of the targets, including target 15, which asks businesses to move towards full sustainability of extraction and production practices, sourcing and supply chains, use and disposal, and reduce associated biodiversity related risks.
There are indications that the industry has got the memo, says Sonter. “I think there’s a broad understanding that social licence to operate is really important and environmental factors need to be considered,” she says. Some mining companies are also investing in solar-powered zero-carbon mines and low-impact extraction techniques that have been compared to keyhole surgery, where minerals are leached out via boreholes rather than dug up. At present this practice only works for uranium, but could be adapted to other metals.
“Here in Australia, when you fly, you see lots of mines scarring the landscape. If we could avoid that, it would be fantastic,” says Henning Prommer at the University of Western Australia in Perth, who is working on a .
At present, however, the minerals boom is also stimulating a lot of unsanctioned mining in places like the DRC. “High prices for strategic metals are driving a great deal of illegal and illicit mining in frontier areas, with severe environmental impacts,” says conservation biologist Bill Laurance at James Cook University in Australia. “Wildcat miners not only degrade the land and water, but also poach wildlife.”
But even conservation biologists acknowledge that the energy transition has to happen, and not just for the sake of the climate. “Mitigating climate change is an incredibly important part of achieving global biodiversity conservation goals,” says Sonter. “We’re not suggesting that continuing with fossil fuels is the way to go.” The balancing act, says Laurance, is to avoid destroying nature as we try to make humanity more sustainable. “That would be the ultimate irony,” he says.
“Destroying nature to be more sustainable would be the ultimate irony”
We have no choice but to walk that tightrope, says Bond. The IEA’s road map for doing so involves six major challenges. Governments must bolster investor confidence; companies need to get innovating; recycling must improve; supplies need to be made more secure, possibly through strategic stockpiling; coordination between producers and consumers has to get better; and environmental and social standards have to improve.
Ultimately, says Birol, it requires us all to dig the fact that when it comes to the energy transition, “minerals are not a sideshow, but a part of the main event”.
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