COP26 has made it plain. The world needs to act to forestall the worst effects from the greatest existential threat our society has ever faced, namely climate change. Everything we have done in the west to combat this problem, so far, has been market-driven. Our greatest “success” has been the shift from coal to less-expensive natural gas to generate electricity, but in practical terms other efforts have been inadequate or inconsequential. Governments talk about taking action but do nothing, probably because they are unsure what to do. We are going to offer a few suggestions and project what resulting critical material demand could be in the face of their adoption.
We first need to understand that the origin of man-made carbon emissions in the U.S. are shown in Figures 1 and 2.
COP26 concludes that we must achieve a 43% reduction in CO2 emissions by 2030 and net zero emissions by 2050, but acting sooner at any scale is better than later. I would suggest that progress will be made only if the actions we take will not be overly harmful to the economy. That makes the task daunting, but not impossible.
First proposal – transportation
Major western governments should announce, as soon as possible, that all new vehicles sold will meet emissions standards mandating that these new vehicles are hybrids, plug-in hybrids or battery-electric vehicles (HEVs, PHEVs or BEVs). This will dramatically reduce emissions from the transportation sector and, since HEVs and PHEVs can already be sold at essentially the same price as internal combustion vehicles (ICVs) there should be little negative economic impact.
For those seeking to make “perfect” the enemy of “better”, mandating BEVs cannot work in the long run, not without massive disruption in other sectors. For example, the U.S. used 520B litres of gasoline and 181B litres of diesel fuel in 2019. That represents a lot of energy. If we were to try to replace that energy with electricity, we would need to generate 60% more electricity than the U.S. generated in all of 2019 and we would need to ensure the grid could deliver it to all the new chargers required, a task that will not even be remotely close to completion by 2050, much less well underway by 2030. By mandating adoption of HEVs, PHEVs and BEVs, we believe emissions from the transportation sector could be reduced by 50% or more over time, with the present grid sufficient to charge PHEVs overnight and fossil fuels providing additional energy to HEVs and PHEVs when needed.
Perhaps the most welcome impact of such a change would be that many of the batteries in vehicles would be small. This means the typical cathode active material in those batteries could be lithium iron phosphate, eliminating the need for rare metals such as cobalt in these batteries. If all new passenger vehicles in the world became HEVs, PHEVs or BEVs, lithium demand from this use alone would be 1.8Mt, based on roughly 80M new vehicles, average battery size of 25 kWh and current LFP energy density. While this demand would greatly increase lithium demand, worldwide lithium reserves are more than 117Mt LCE, according to the USGS. Time and investment could increase lithium supply to required levels.
We will also likely need the rare earths neodymium, praseodymium, dysprosium, and terbium to make the powerful magnets that are the core of the simplest electric motors for driving electrified vehicles down the road. Here, the eventual demand is more tractable. There are plenty of rare earth deposits out there. At present prices, and with guaranteed demand, we can double output of these required materials and support new mines.
Second proposal – cleaner electricity
As soon as possible, mandate the replacement of coal power with non-carbon generation, including renewables (where possible) and nuclear, hydro or geothermal (when necessary). This has another potential huge impact on global CO2 emissions (see Figure 3).
While solar and wind are not reliable enough to entirely replace coal, there is capacity within the grid to expand their use. Nuclear is an effective replacement for coal, but the world does have serious limitations regarding uranium reserves. The World Nuclear Association reports that uranium reserves total 6.15Mt, but current annual need is roughly 67,000t. If we dramatically increase uranium demand, global reserves will only last two or three decades.
What we suggest is using current reactor designs that can be fuelled with mixed uranium and thorium fuel. Combining thorium with uranium can dramatically reduce lifetime need for uranium but requires a reactor design that is capable of using such a fuel. Fortunately, there are licensed and proven designs that can use mixed uranium and thorium fuel, something that would actually improve reactor safety.
We have the deposits of uranium, but time is not our friend with respect to their development
The impact of such a change would be particularly large in China. However, Chinese authorities would likely view a dependence on foreign uranium as decreasing their energy security, since China does not have large conventional domestic uranium reserves. Governments would likely have to find ways to guarantee necessary supply to China in order to allow such a generating shift to take place, but this is one of the best targets for CO2 reduction available globally and something that all governments should work to enable.
Of course, what we require to make such a change is more uranium and more of the material that goes into reactors, including zirconium. Thorium is plentiful, thankfully, but we would need an entirely new industry processing thorium oxide for use in reactor fuel. We have the deposits of uranium, but time is not our friend with respect to their development, at least not without incentive to develop them more quickly.
Third proposal – target the real enemy
There are several specific industries that government must target. One is not a major polluter, but serves to demonstrate technology that could then allow a technology shift in the other.
Aluminium is made by electrolyzing aluminium oxide. A very hot bath of salts can dissolve a small amount of aluminium oxide, allowing an electric current to pull aluminium to one electrode, collecting the aluminium as molten metal while sending oxygen to the other electrode. These electrodes are, presently, made of graphite. When oxygen reaches the graphite electrode, it combines with carbon atoms and creates carbon dioxide. In essence, the production of aluminium has a CO2 co-product.
It is possible to replace the graphite electrode collecting oxygen with a conductive ceramic electrode. The result will be improved reliability, lower operating costs and reduced electricity consumption. In fact, it is possible that the produced oxygen gas could now be collected and sold for profit.
Unfortunately, the aluminium industry is simply not large enough and does not produce enough CO2 to make a huge difference on its own. But making steel combines hot iron oxide with powdered metallurgical coal in a blast furnace to create molten iron and carbon dioxide. It is entirely possible to, using ceramic electrodes and electricity, make molten iron directly from iron oxide using electrolysis.
According to Rio Tinto, each tonne of steel made today uses 770kg of metallurgical coal (plus more coal to make coke from metallurgical coal plus other energy needs). Converting the making of iron and steel to an electrolytic model would dramatically reduce carbon emissions. But this simply will not happen without government intervention.
Fourth proposal – stand-alone houses
Residential and commercial buildings are built to the standard of a local building code. As quickly as possible, relevant governments should move to require new construction to meet passive building standards. Passive buildings are designed to dramatically reduce the need for active heating and cooling, by as much as 90%. And apart from the passive building standard, in all regions that would benefit from it, a requirement to install appropriately-sized solar hot water systems should also be put in place.
The U.S. government has done studies on homes and on energy use within various types of homes (Figure 4). In the U.S., an average of 71% of the energy used by a home is used for heating, cooling and making hot water. Even in Canada, where a disproportionate amount of electricity is generated by green sources, home heat and hot water are largely generated from fossil fuels like natural gas. Eliminating much of the need for this energy in new buildings would provide, over time, a significant reduction in CO2 emissions. And given the long life of new buildings, it is better to begin requiring this type of construction as soon as possible.
The result
Many people feel that we are powerless against climate change, that there is no way to make meaningful reductions in CO2 emissions without doing serious economic damage to our society. This is simply wrong. However, if you are hoping for the market to incent lower carbon emissions quickly enough to make a difference, you are being foolish. We require government action. Carbon taxes might work over time, but we need reductions starting now. Gradual increases in carbon taxes would simply be too slow. Governments can and should attack specific targets where CO2 emissions can be reduced without excessive disruption of the economy and leave the carbon taxes to act indirectly and in a gradual manner on other sectors over time.
And to do anything like the above, we will need various critical materials. Our First Proposal requires lithium chemicals, primarily lithium hydroxide, and rare earths to be implemented. The Second Proposal depends on available low-enriched uranium and thorium for nuclear reactors, along with rare earth elements and perhaps chemicals such as tellurium for use in wind turbines and thin-film solar cells. The Third Proposal will require materials such as yttrium, zirconium, and some rare earth elements to make the appropriate electrodes, plus the electricity from the Second Proposal. And the Fourth Proposal, with greater use of insulation in construction, will require larger amounts of chemicals such as borates.
In short, we can meaningfully reduce CO2 emissions without crushing our economies, but we need the political courage to try. Sadly, it seems that we have much less political courage in our society than we have carbon emissions, but all it might take is one courageous political leader. Do we have a volunteer?
