The "Temporary" transition

Few things have been as transformative to our civilization as the harnessing of fossil fuels. In terms of the velocity of the impact, the use of fossil fuels may eclipse even the discovery of fire, or that of the agricultural revolution. Starting in the 19th century coal put the industrial revolution on steroids and the modern world can simply not function without them. A few people of a 'certain' age should find it quite easy to imagine a world without the internet, but even the most secluded communities may find it difficult to imagine our world without fossil fuels.

But this is exactly the challenge of the first half of the twentieth century; to imagine a world without fossil fuels. We've done most of the imagining part (The sun and wind seem a limitless supply of cheap clean energy) but now we find ourselves entrenched in the murky quagmire of implementation. And while a lot of the debate of the last 20 years focuses on the lack of political will and economic fallout from the transition, several key technical problems are yet to be resolved if we are to imagine a truly sustainable world.

Problem 1: Element 3

Contrary to popular belief, lithium-ion batteries are not the most abundant source of energy storage in the world. That happens to be pumped storage hydroelectric (basically using excess energy to pump water to a higher altitude and then using turbines to convert the potential energy back to electricity when needed). However, lithium-ion batteries are the technology that receive the greatest investment for research, production and recycling. roughly $190 Billion was allocated to this purpose by the US matched by Global investment in the technology. While this may suggest that the production and supply chain of these batteries may soon rise to reduce reliance on fossil fuels there is a glaring flaw in their appeal as a long-term solution.

Element 3 (Lithium) is an incredibly rare element. Current proven reserves are 28 million tons of which we consume roughly 1.3 million tons annually. Even if we take optimistic figures of undiscovered reserves of 70 million tons and account for the increasing consumption trends, we have a little over 50 years' worth of lithium on the whole planet. The mining of lithium is expected to become unviable long before reaching that mark and while significant investment is going into the recyclability of these batteries, a global infrastructure for collection, sorting, safety and reuse of these batteries would increase costs and potentially prolong the use of fossil fuels. The recycling methods themselves (pyrometallurgical or hydrometallurgical) are energy-intensive or produce harmful emissions and it may be decades till recycling infrastructure keeps pace with energy use let alone production infrastructure. Yet lithium-ion seems to have become the de facto solution to replace internal combustion uses such as those in cars, appliance, homes, and potentially ships and planes. With luck we might be able to eke out 30-50 year with these but that's a heartbeat on civilization timescales.

There are alternatives in development; magnesium is a viable alternative, being very abundant (2.5% of the earth's crust and 0.12% of sea water) but most of proven reserves are in China, Russia and North Korea. Understandably, western governments are hesitant to build a civilization on a material that's supply is controlled by known adversaries. Sodium is an equally abundant mineral, but current batteries are not as energy dense for mobile use and the research investment in both technologies is miniscule compared to that going into lithium-ion.

Problem 2: Rare earth elements are spoiler rare

A lot of incredibly rare materials go into the production of objects we use every day. From camera drones to LED screens or smart watches, modern electronics are made up of a smorgasbord of these rare-earth elements (REEs). While recreational uses might not dent global reserves as much, if we have decided that electrification is the de facto answer to decarbonization, we will very soon run into a bottleneck for these very rare materials.

The most likely bottleneck is the metal neodymium, used to make high powered permanent magnets used widely in motors for electric cars and turbines for wind turbines. In fact, the application of neodymium magnets was one of the major breakthroughs that resulted in Electric vehicle with sufficient horsepower to rival combustion vehicles. A standard EV contains 3-5 kgs of neodymium. At current extraction levels we cannot produce more than 1.5 million EVs in a single year (Assuming no other uses). For comparison there are 1.4 billion combustion vehicles in the world to be replaced with 70 million sold every year, so we need a 50-fold increase in production just to keep up with current demand.

As we invest more and more into materials for the future, we might face more bottlenecks of materials that are either hard to fabricate or unsustainable to mine endlessly

Problem 3: Tritium is tricky

Before Solar and wind became the main drivers of the green transition, nuclear power held the promise of a future free from fossil fuels. From 1945 to 1984 400 new nuclear plants were commissioned. In the following 40 years, 96 were added and a similar number were decommissioned. Resulting from significant accidents like Chernobyl and Three-Mile Island.

In the last couple of years, governments seem to have realized this intransigence and are scaling up investments in nuclear power plants with investment averaging $40 Billion a year from 2016-2022. However, the biggest roadblock to current fission-based nuclear power plants is the massive amounts of nuclear waste they produce. Much of the waste produced in the last 80 years will still be radioactive and dangerous for a thousand years and there is no near-term solution to tackling that waste. Newer reactors based on latest research produce less waste of isotopes with much smaller half-lives (decades not millennia) but also lose efficiency and scale compared to older designs.

One technology that has long promised to solve this problem is Fusion based nuclear technology. Fusion based reactors harness the same mechanism that powers the sun and are orders of magnitude more efficient than fission-based reactors. resultantly the waste produced is also much less and generally harmless. The current designs are also considered to be much safer than current fission reactor designs. It's also extremely hard to divert these reactors to the production of nuclear weapons. That is also the reason that private investment into the technology has seen an uptick. So, what's the catch? Unfortunately, current designs require more energy to initiate the reactions than they produce out of them (So in a way they are not power plants at all).

Assuming that we do get around this difficulty we run into the same challenge of increasingly rare materials. Fusion reactions require extremely rare isotopes of hydrogen deuterium and tritium. Tritium is extremely rare with only 7-20 kgs naturally occurring on earth. More can be produced in breeder reactors using Lithium-6 (which in itself is rare) but that only increases the energy intensiveness of the process. That is the reason that this technology is considered a moonshot, or one that is awaiting the maturity of the space economy to flourish (Tritium is thought to be plentiful on the moon). Without a significant breakthrough we are stuck with inefficient and dangerous reactors that would be inadequate to replace coal and oil power plants.

Is there Hope?

None of this is to say that we should abandon these technologies or that the green transition is fanciful thinking, but rather it is important to think of the longer-term energy needs of humanity, so that we don't need to transition again 20-30 years down the road. Afterall when the first pioneers started burning fossil fuels, they probably never considered the planet-altering effects of their innovation. Material sciences and innovation don't work like the internet. Solar PVs took decades to become household even after becoming financially viable and still only account for less than 10% of all energy consumed in Europe (5% for the world). The modern economy is so massive and complex that even ground-breaking scientific breakthroughs take decades to industrialize and scale up enough to solve problems on a global scale.