Is the electric revolution going to run out of key metals?

For years, whenever I went to an event talking about electric vehicles, there would always be some chap jabbing his finger and saying, “Yes, but where’s all the lithium going to come from, eh?” I’m sure you’ve met the same type of guy (and it is always a man).

It’s a fair question, but the way it was asked tended to undermine the argument. It was always obvious that this was someone desperate for the EV lobby to be proved wrong, so I had to suspect whatever they said was guided by motivated reasoning. History makes the ‘we’re running out’ argument just feel like crying wolf – Limits to Growth never happened, Peak Oil never happened, we’ve been here before surely?

“… the age of electricity and of copper will be short. At the intense rate of production that must come, the copper supply of the world will last hardly a score of years. … Our civilization based on electrical power will dwindle and die.”

Copper mining expert Ira Joralemon, in 1924

Now, however, the argument seems a little harder to dismiss. Every few days I see a new article or report about the coming supply crunch for the various metals needed in EVs (and solar panels, and wind turbines, and everything else electric).

Most recently I saw a presentation using copper as an example – it’s the third most used metal in industry, after iron and aluminium, and of course it’s used in everything electrical. It’s easy to paint a pretty dire picture, using reports from mainstream sources like the International Energy Agency and S&P Global. Inventories are down, we’re having to process ores of steadily lower quality, and new mines take over 10 years from discovery to production.

But again, we have been here before. Wikipeadia points out that in 1924 geologist and copper-mining expert Ira Joralemon warned: “… the age of electricity and of copper will be short. At the intense rate of production that must come, the copper supply of the world will last hardly a score of years. … Our civilization based on electrical power will dwindle and die.”

So what are we to conclude? Without pretending to be a minerals expert, here’s what I think we need to take away:

First, in the long term, metal shortages won’t stop the move towards electrification of society. We’ll find new metal deposits (astonishingly I just read that only 40% of US territory has been geologically mapped in detail). We’ll make more of our wiring out of aluminium, we’ll commercialise different battery chemistries. We’ll do things that nobody has thought of as yet.

Second, in the short term, prices will go up. It’s fair to say that we’ve left tackling climate change to the eleventh hour, and so we have ridiculously steep targets to reduce emissions. Transforming our energy system in a matter of just a decade is going to bump up against the timelines to build new mines or take a new type of battery from the university lab to the car showroom. We’re already seeing battery prices increase after decades of falling.

Third, we (obviously) need to be as efficient as possible in our use of energy and resources – and those high prices will help force this. In the case of transport, it means that SUVs are still a bad idea, even if they’re fully electric. We may want to re-examine the case for plug-in hybrids vs fully electric – more on that in a future post. And we will need diverse strategies – a variety of low carbon liquid fuels, travel demand management, modal shift, i.e. every tool in the box.

Finally, there will be winners and losers, and we are probably right to worry about the destabilising effect of that on global politics. It’s true that China currently processes a huge proportion of many of the key metals. It is unfortunate that this supply deficit is looming just as governments around the world are backing off from globalisation and returning to national interest and protectionism.

It is worrying that in pushing for domestic resource extraction, the US and Europe may well prioritise this strategic interest over nature, indigenous communities and clean air and water. And in countries with less stable institutions, concentrated mineral wealth historically does more harm than good, propping up corrupt and authoritarian regimes.

To end on a slightly more optimistic note, our response to the pandemic has proved that technological developments that used to take 10 years can happen in two, if there’s the will. Let’s hope that applies to new types of battery, motor or mining techniques as well as vaccines.

The ‘where’ approach to sourcing green hydrogen…

So, can we import lots of green hydrogen from places with abundant renewable electricity potential, but no market within cable-laying distance – what I call the ‘where’ solution? The short answer is much the same as for making hydrogen from curtailed renewables here in the UK, i.e. yes we can but it’s likely to be quite expensive, so its niche will be restricted to those areas with very little other option to decarbonise.

There are various ways that hydrogen could be transported, the main ones being:

  • Pipeline
  • Compression
  • Liquefaction
  • Convert to ammonia or methanol
  • Lock into metal hydrides or liquid organics

Since hydrogen is literally the least dense form of chemical energy in the universe, transporting it is inevitably going to be difficult. The following article does a good job of explaining those difficulties in detail –

I’m not technically qualified to attest to its accuracy, but even if the specifics can be debated, the broad picture is clear – moving hydrogen over long distances entails additional energy losses and significant capital costs. Just to recap the key points in brief:

Pipelines – hydrogen is a very small molecule that will leak through any sort of plastic pipes, and makes most types of metal pipe brittle and thus more likely to crack. Its low energy density means using a lot more energy in pumping a given amount of energy through a pipeline compared to natural gas.

Compression – very high pressures needed, lots of energy used in compression, and hoop stress limits the size of individual cylinders. Simply not practical for large quantities.

Liquefaction – hydrogen liquefies at -249degC (only 24 degrees above absolute zero), and has a reverse Joules Thompson effect, so that it warms when it expands at temperatures above -200degC. It therefore has to be pre-cooled with liquid nitrogen before final cooling via expansion. The whole process is very energy intensive, and boil-off rates are high.

Convert to ammonia – this releases heat at the point of production (which will probably be wasted as that’s where you have cheap energy) and requires high grade heat to convert the ammonia back to hydrogen at the destination. Ammonia is also poisonous in general, and poisonous to the catalysts in hydrogen fuel cells in particular.

Convert to methanol – as with ammonia, methanol is a useful product, or a fuel, itself, and as a liquid at room temperature is relatively easy to store and transport. The major problem is that it requires a supply of CO2 (and that CO2 will be released when the methanol is burned or turned back into hydrogen). If one has a source of non-fossil CO2 available, either from an AD plant, direct air capture or other, the question is whether it would be better to just bury it rather than make and transport the ethanol?

Lock into metal hydrides or liquid organics – this approach may well have a niche, but in both cases (as with ammonia) heat is needed at the destination to release the hydrogen, and the weight of the carrier has to be transported in both directions, so again round-trip efficiency is low.

So, should we conclude that this is just a non-starter? Well, apparently not. At the ITT Hub show last week I visited the Air Products stand, where they were talking up their plans to make green hydrogen, and convert it to ammonia, in Saudi Arabia, then ship it to a terminal in the UK to turn back into hydrogen. Saudi Arabia may have the world’s largest oil reserves, but it also has huge potential for wind and solar power, and a lot of ready capital to invest. I for one will be watching the development of this project closely to see whether it’s just Saudi greenwashing or whether the economics really stack up.

It’s also worth noting that the world’s second largest shipping line, Maersk, has bet on methanol as its route to decarbonising its ships. They will burn the methanol directly though, rather than converting it back into hydrogen. (I’ll write another post in a few weeks about this.)

Ultimately, I would broadly agree with the conclusions of the article I quoted:

  • Firstly, before we start finding other uses for green hydrogen, we need to make sure we replace all the grey hydrogen we use right now.
  • Second, rather than trying to move hydrogen long distances, we should move some of our industries to the hydrogen supply. An obvious example is to use hydrogen in Western Australia to process Australia’s iron ore and make low carbon steel – then export the metal rather than the hydrogen. All our fertiliser should be made in similar places.

Cheap electricity for hydrogen production – a few more thoughts on the ‘when’ approach

So, a couple of people have responded to my last post and prompted me to take a deeper look at the ‘when’ approach – i.e. using curtailed renewable electricity to make hydrogen. The main source I’ve taken a look at is the latest version of National Grid’s ‘Future Energy Scenarios’ report. They model the whole energy system of the UK, across all sectors, and offer four different scenarios out to 2050, three of which assume we hit net zero (plus one ‘business as usual’ comparator).

The number one consideration in thinking about the role of hydrogen is what we’re going to do about heating. Overall our energy demand for heating is about several times larger than what we use for surface transport (road plus rail). Historically, in the winter peak the gas grid has delivered up to seven times the amount of energy per day that the electricity grid delivered – most of which was going to gas boilers.

On the face of it, winter heating demand suggests that to switch to mostly renewables would require an awful lot of spare capacity in the summer in order to meet the peak in the winter.  The suggestion is that using spare summer capacity to make hydrogen as a balancing mechanism is cheaper than battery storage (which isn’t viable over a timescale of months anyway).

As it turns out though, there are a number of other factors that will work to lower the winter/summer capacity imbalance. Specifically:

  • Improving building insulation and thus reducing heat demand is a key part of any serious strategy
  • Heat pumps are considerably more efficient than gas boilers, which will also lower the winter energy peak in the future
  • The wind blows more in the winter than in the summer
  • As the climate warms, we’ll want to use more air conditioning in the summer (which we’ll have if we install heat pumps, because they can also deliver AC)

Despite these factors, there will still be a capacity imbalance on a longer timescale than can be addressed by demand response like smart charging of EVs overnight.

Interestingly, only one of the three main scenarios suggests much hydrogen going into surface transport. That’s the ‘system transformation’ scenario, which models a future in which government makes big investments in things like making ‘blue’ hydrogen (i.e. steam reforming natural gas with carbon capture and storage), alongside nuclear etc. In this scenario, consumers resist changes like heat pumps, so the energy system is transformed upstream and hydrogen plays a big role.

In the other two scenarios, hydrogen is mainly made by electrolysis, and most of it goes to industry, aviation and shipping. Relatively little is stored to turn back into electricity, presumably because storing hydrogen is quite hard (salt caverns are the main proposal) so it makes more sense to turn it into industrial products (fertiliser) or fuels (methanol, ammonia) and store those instead. In these scenarios almost no hydrogen goes to fuel cell road vehicles or trains.

So, what do I conclude? Well, I still think hydrogen will have a significant role to play. But, unless we have more of a ‘command and control’ approach to the energy system than recent governments have had an appetite for, it looks like the energy models agree that the hydrogen we do produce as part of balancing the grid will still go to uses where there are no other alternatives, rather than widespread use of fuel cell vehicles. Its use in road transport will remain expensive compared to batteries and therefore confined to a few use cases.

Of course I could be wrong… Next, the ‘where’ approach – could cheap hydrogen imports make its use more widespread?


How are hydrogen producers going to get their hands on lots of cheap electricity?

First of all, let me make clear that I’m not ‘anti’ hydrogen – I absolutely think we’re going to need it for some applications. For a start, we’ll have to replace all the ‘grey’ hydrogen we currently use to make fertilisers, and we’ll probably need a lot of hydrogen for steel-making. In applications like that, where there is not really any other zero carbon choice, the question is not whether to use non-grey hydrogen, but how best to do it.

So my question about hydrogen is really about using it where there are competing options – such as in vehicles. Where does the line get drawn between turning electricity into hydrogen and then back into electricity, vs just using the electricity? Physics says that the hydrogen option is always going to need a minimum of twice as much energy compared to using the electrons directly, so for hydrogen to compete, it has to use electricity that is half the usual price, or less.

As far as I can see, there are two possible options for finding cheap renewable electricity to make hydrogen – either ‘when’ or ‘where’. The ‘when’ option is to use curtailed renewables – wind power generated in the middle of the night for example. And the ‘where’ option is to hook up an electrolyser to a wind turbine out at sea or a solar farm in the Australian outback (rather than lay a cable).

Let’s look at the when option first (I’ll tackle ‘where’ in the next post). At the moment, in the UK, if the wind is blowing in the middle of the night, some wind farms get paid to switch off rather than damage the grid, so the electricity price is effectively negative. I can see why people get excited about hydrogen when looking at this. However, I had a client who asked me to assess the feasibility of producing hydrogen from curtailed power, and for now the numbers don’t stack up. The problem is that electrolysers are a big up front cost, so an operator needs to run them continuously in order to generate a return on investment – only running them when there’s excess electricity on the grid is not good enough for investors.

Even if the price of electrolysers falls significantly, my guess is there won’t be enough curtailed power to supply them, for two reasons. One, we are rapidly moving towards a smart grid in which consumers and energy companies collaborate to match demand to supply. And two, we are seeing exponential growth in electric vehicles, which will be left on overnight to be charged at the discretion of the smart grid whenever power is cheapest. Effectively, all those EV batteries will be soaking up the cheap electricity leaving none to make hydrogen.

I would really welcome comments on the above from anyone who has more detailed modelling of the UK electricity grid. My thoughts are purely qualitative, so maybe the scale of renewables we need to meet peak demand is such that we’ll have a huge amount of curtailed power even with EVs and a smart grid. But my suspicion is that the market will match the two, and not leave much for hydrogen production. So what about the where option? That’s for my next post…