Scientifically reading your tea leaves

Environmental specialists compute a sustainable future

Mine Workers in Mineral Springs, ca. 1890.

If mankind is to switch to a more sustainable economy, we will need other resources. But will there be enough of them? Yes, according to calculations by Leiden environmental scientists. “We have the technology and we have the resources.”

Let’s say we decided to try and tackle climate change after all. Let’s say we actually managed to reduce global CO₂ emissions. It will be hard enough to grasp the financial consequences, but the same is true for ignoring the problem. Anyway we, mankind, could decide to do it.

Then obviously, it would be useful to have some alternatives. Financial pain is one thing, but giving up our transportation and our electricity would hurt much more. A low-carbon economy would mean that our fleet must be electric, for instance.

And another thing: coal-fired power plants always work and work about as much as you want them to. If the whole of Europe were to switch to renewable energy sources, the entire electricity network would need to be overhauled to compensate a temporary lack of wind in one country with extra water power in another region of the continent.

We can’t do all of that without encountering some problems. We’ll need raw materials to construct those alternatives, so we need to know they’re available. “Luckily, it’s not necessary, but should you want to store renewable power in gigantic lithium batteries, you can forget it”, environmental scientist Arjan de Koning says to illustrate the point: the global production of lithium simply isn’t large enough.

De Koning and his colleagues discuss whether we would have enough of the resources needed for low-emission life in an article in the specialist journal Resources, Conservation & Recycling: How much more copper do we need for our electric wires? How many metals like neodymium do the dynamos in our wind turbines require? And so on, for eleven different types of metal.

De Koning and his colleagues have based their calculations on a fairly optimistic vision of the future, in which we do absolutely everything we can do reduce or contain CO₂ emissions. For instance, all homes are heated by green electricity. All power plants that still emit CO₂ should intercept the emissions in their chimneys and the whole of our global car fleet should switch to electric engines.

Such measures mean that the world-wide production of metals listed in the paper would need to increase substantially. And an increase is possible, apparently. Some mines will need to raise their production and perhaps a few more will need to be opened, but in theory, with the current production growth and the reserves, it should be enough. Only the production of the semiconductor indium, used in electronics and solar panels, might lag behind the demand, but that is a special case.

“At present, indium is a by-product of zinc mines; some refineries extract it from the zinc ore while others don’t. As the global demand for indium rises, and consequently its price, the production could be scaled up relatively easily”, De Koning explains.

He would like to point out that, of course, it’s only a model. “It’s like scientifically reading your tea leaves. We know how large the stocks are, how the market has responded so far, what the prognoses are for the growth of the global population, etc., but if there’s a major technological breakthrough or wide-spread armed conflict, the world could be a very different place in 2050 than the one we’re computing.” Having said that, he’s sticking to his conclusion: “It’s unlikely that those eleven substances will form a bottleneck in a transition to a low-carbon economy.”

That’s the good news. The bad news is threefold.

Firstly, the availability of metals does not mean that we will make that transition. It would require huge amounts of decisiveness, agreement and investment. “In fact, there should be a global tax on CO₂ emissions so that renewable energy can compete with the dirt-cheap coal-fired plants”, De Koning sighs.

Secondly, De Koning uses the slightly artificial term “low-carbon” instead of more commonly used expressions like “sustainable” and “clean” because, although this energy is quite clean, you need to mine those metals before they become available. And mining is not a very clean enterprise at all. “It’s difficult to compare our entire CO₂ emission in a chain with the local impact of a mine, which is frequently disastrous. Large open pits that spread dust or toxic residual matter, sometimes in vulnerable ecosystems like the Amazon rainforest. Our article doesn’t focus on that, but it’s certainly something we need to consider.”

And lastly, even in the Leiden scientists’ most technologically optimistic vision, the earth will be four degrees warmer. “I’m reasonably optimistic about the resources issue”, continues De Koning. “But I’m not so sure about the climate goal of a rise in temperature of no more than two degrees, which was agreed in Paris. We have the technology and the resources – that’s not the problem. But the rising population and economic growth are against us and many countries have not succeeded in reducing their emissions. I’m constantly tossed between hope and fear, I guess.”

Bart Braun

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