Material World: A Substantial Story of Our Past and Future

by Ed Conway

Between 2004 and 2016 Chilean miners increased annual copper production by 2.6 per cent. Yet the amount of ore they had to dig out of the ground to produce this marginal increase in refined copper rose by 75 per cent.

But solar panels need roughly seven times as much copper as conventional power stations while offshore wind needs about ten times as much copper to generate the same amount of power.23 Perhaps

Without copper there is little hope of fulfilling any of the net-zero blueprints designed by governments and environmental institutes around the world. So, as our appetite for electrification intensifies, some intrepid explorers are seeking out deeper, darker and more controversial places to get this metal.

Oil and gas are by their very nature far trickier to substitute since they represent an almost perfect energy source and a near irreplaceable feedstock into nearly every manufactured product. Weaning ourselves off them will take far more than a bit of goodwill and a net-zero target.

That needle coke – a hard, black, stony substance, which looks a lot like coal – is the main feedstock for the production of synthetic graphite, the chief ingredient in the anodes in lithium-ion batteries. Most of us now realise that the batteries inside our smartphones and electric cars are made of many obscure ingredients we dig out of the ground – more on this in Part Six – but few are aware that among those ingredients is a big dollop of crude oil.

Much of what we eat today is, one way or another, a fossil fuel product.

regarded as the future for the cultivation of our crops. With the world’s population projected to surpass 10 billion later in this century, we will have to produce more food in the next four decades than all farmers have in the past 8,000 years.

Since carbon dioxide is, alongside light, the main input into photosynthesis, you can dramatically accelerate the rate of growth by increasing the CO2 content inside the greenhouse from the atmospheric average of just over 400 parts per million to 800ppm or even 1,000ppm.

Yet the chlorophyll inside these tomatoes contains carbon from natural gas, hydrogen from natural gas and nitrogen from fertiliser (which is produced with natural gas). They are made of fossil fuels.

As a result, a kilogram of greenhouse tomatoes generates as much as 3 kilograms of carbon emissions.

There are many, many different varieties of plastic – thousands in fact – but few are quite as versatile and useful as polyethylene. It can be spun into ultra-high molecular weight varieties that are stiffer than steel or into low-density sheeting, which is as soft as wax. Its incredible ductility means it will tend to stretch rather than breaking. Water resistant and durable, heatproof up above water’s boiling point yet recyclable, polyethylene could be strung into strands strong enough to deflect bullets; its non-conductive properties meant it was the perfect electrical insulator.

ships and submarines for avoidance and attack.9 ‘The availability of polythene,’ said Sir Robert Watson-Watt, the man who discovered radar, ‘transformed the design, erection, installation and maintenance of airborne radar from the almost insoluble to the comfortably manageable.’

And by playing around with this molecular structure, polymer designers can vary its strength and behaviour enormously. Pack the chains close together so they crystallise and you might end up with a hard, rigid plastic bottle; space them further apart, with fewer microscopic plastic crystals joining them together, and you have a bottle you can squeeze ketchup out of. Vary the length and something similar applies: the bulletproof vest version of polyethylene (ultra-high molecular weight) involves strands that – if they were the width of spaghetti – would be about 250 metres long.

Polyethylene isn’t the only plastic – indeed it’s one of five main families of human-made polymer. There is polystyrene, famed for its puffy packaging foam but equally capable of being moulded into a hard, clear plastic. There is vinyl – polyvinyl chloride – from which you can make hard pipes or soft shower curtains. There is nylon, famed for its silky stockings but just as easily moulded into hard machine screws. There is polypropylene, flexible enough to be used as the lid of a flip-top bottle but hard enough to be formed into furniture. There are also thermosetting materials like epoxy resin,

With plastic packaging we no longer had to melt down as much sand into glass or chop down as many trees and turn them into paper and card. Polyethylene insulation helped safeguard the Malaysian gutta-percha tree, not to mention other materials too. A Bell Labs report in the 1970s found that if America had continued to sheathe its telephone cables with lead rather than polyethylene, this use alone would have consumed four-fifths of all the lead produced in the country.

And while it is possible to recycle plastics at scale, the challenge is that while some types of plastic are perfectly suited to being melted down and remoulded, others are not. Soft drinks bottles made out of polyethylene terephthalate (PET), for instance, could easily be re-formed into a polyester fleece. But add a different type of plastic to the recycling process, a thermosetting one for instance, and what comes out is a bit of a mess. One argument about why plastic recycling rates remain so low (only about 25 per cent in Europe and 10 per cent in the US, compared with 80 per cent for steel) is that it is simply too complex, with consumers asked to distinguish between seven different types of plastic (those recycling codes you sometimes see on bottles) before putting them in the correct bin. The other argument is that the virgin material, those nurdles being churned out of ethylene crackers around the world, are so cheap that recycling makes little economic sense.

Were China to shift all its coal-fired power stations on to gas, then the world would immediately be on track to hit its climate goals.

in future we may, once again, use this extraordinary substance less as a fuel than as a chemical ingredient. The complex products distilled in refineries could help us make the battery ingredients we need to help us deal with the intermittency of renewable power. They can help us manufacture the resilient plastics we need for the biggest, toughest wind turbines. But there is no point in pretending either that this will be easy or that it will come without some uncomfortable compromises.

This is a magical metal: alongside hydrogen and helium it was one of the three primordial elements created in the Big Bang,

No other element has quite the same combination of lightness, conductivity and electrochemical power. No other metal is quite as good at storing energy. So light it floats in oil, so soft you could cut it with a kitchen knife but so reactive that it fizzes and bangs when it makes contact with water and air, it is one of those materials you don’t ever see in its elemental form outside of a chemistry lab.

The way this type of lithium mining works is relatively simple. The ancient brine is pumped out from under the salt crust, from brine wells located all over the Salar. It is channelled into gigantic ponds where the water is evaporated away. It is a slow process taking many months: first the sodium chloride precipitates, then the remaining brine is channelled into another big pond where the potassium salts precipitate, then into another evaporation pond where the magnesium salts are removed. Eventually, after well over a year, that brine that left the underground reservoir as a pale blue liquid has been concentrated into a yellow-green solution, almost as bright as a neon highlighter. At this stage, it is about 25 per cent lithium chloride, though the green colour actually comes from the boron still left in the solution. You

Yet it is also hard to escape a more discomforting thought: are we just replacing one form of environmental footprint with another?

The real question is not so much whether enough exists but what it will take – both in terms of money and environmental impact – to remove it.

It is being extracted at a rate that far outpaces the Salar’s ability to replenish itself but no one is altogether sure what constitutes a ‘safe’ rate. At what point does the exploitation cause an irreversible change in the local environment?

this time there are three important differences. The first is that this time around we are moving down the energy ladder rather than up it. Lithium-ion batteries are significantly less energy-dense than oil, gas or even coal. The second is that the materials we are mining are not being burned; their power is not being vaporised but installed inside batteries, which could, in theory at least, be recycled. The third is that the countries doing the extraction are no longer so sure that they want to do it any more.

Actually, cell manufacturing has something of the 1980s about it, which is not surprising since it is a close cousin of cassette-tape manufacturing. Both involve pasting a chemical slurry on to thin sheets and then winding them up, and this reel-to-reel manufacturing works equally well for those spirals of electrodes wound up inside a lithium-ion battery as it does for the magnetic tape in an audio cassette.

This dominance may not be especially obvious on the surface, given many of the cars powered by Chinese batteries still carry American or European badges, but the deeper you delve under the surface the harder it is to escape. For not only do Chinese companies control about 80 per cent of battery production, they also control about 80 per cent of the manufacture of the materials that go into these batteries. This next rung in the battery production chain might seem somewhat trivial, but do not be fooled; after all, the most valuable component of a battery is not the engineering or the casing but the raw materials pasted in slurry form on to those cathodes and anodes.3 Turning lithium and graphite into chemicals pure enough to play the role of cathodes and anodes – perfect matrices in which lithium ions can nest – is such a complicated business that it represents an entire economic sector of its own.

A typical electric car battery contains about 40kg of lithium, alongside 10kg of cobalt, 10kg of manganese and 40kg of nickel. This is before you consider the graphite that goes into the anode.

Umicore is now what you might call an ‘urban miner’. Rather than just refining metals from ores extracted from the ground, it also refines them from waste –

Across the world, the end-of-life recycling rate – the proportion of scrap that goes on to be reused – is somewhere between 70 per cent and 90 per cent. For aluminium the rate is 42–70 per cent; for cobalt 68 per cent; for copper 43–53 per cent. For lithium it is less than 1 per cent.5 The

We will need to get better at recycling wind turbine blades, which are mostly thrown away at present, or sometimes shredded and used in concrete, because they are formed of a thermoset resin which can’t be melted down and re-formed. We will need to work out how to recycle solar panels and wiring and circuitry, and all the other bits and pieces of the Material World.

So one of the hardest steps in the recycling process is actually the first one, pulling the battery pack apart, ideally without setting it on fire.

And this is before you factor in that in each of the previous transitions – the move from coal to oil and from oil to gas – there was a big incentive to shift: manufacturers could benefit from cheaper, more energy-dense fuels. Each previous shift made their lives easier. This time around, the opposite is often the case. Except for nuclear power, we are shifting to less dense sources of energy.

Creating the green hydrogen you would need to feed this fertiliser plant would consume the entire output of what was, at the time of writing, the world’s biggest wind farm, Hornsea One in the North Sea. All 174 enormous wind turbines – which can on a good day produce just over a gigawatt of electricity, enough to power more than a million homes – would need to be given over entirely to those vessels at Billingham.

The manufacture of green steel will gobble up even more hydrogen. Such things might seem beside the point but actually they are precisely the point. These industrial processes account for even more of the world’s primary energy use than the bit most people talk about – the generation of electricity. Electricity, it turns out, is the easy bit.6

There is, you will have noticed, no way of mass producing either wind turbines (or, for that matter, the silicon substrates of solar panels) without the use of fossil fuels. For the time being, the only way to turn silica into silicon metal is by smelting it with coking coal. Meanwhile, the blades of the wind turbine, in particular, are made out of resins that are primarily extracted from crude oil and natural gas. The story is similar elsewhere: you cannot make high-performance lithium-ion batteries without using graphite obtained from crude oil.

Consider what it takes to replace a small natural gas turbine, pumping out 100 megawatts of electricity, enough for up to 100,000 homes, with wind power. You would need around 20 enormous wind turbines. To build those turbines you will need nearly 30,000 tonnes of iron and almost 50,000 tonnes of concrete, along with 900 tonnes of plastics and fibreglass for the blades and 540 tonnes of copper (or three times that for an offshore wind farm). The gas turbine, on the other hand, would take around 300 tonnes of iron, 2,000 tonnes of concrete and perhaps 50 tonnes of copper in the windings and transformers. On the basis of one calculation, we will need to mine more copper in the next 22 years than we have in the entirety of the past 5,000 years of human history.7 Here, however, is the most unsettling thing about this vision of the future: many of us – perhaps most of us – will never get to experience it.