The triumph of electromagnetism over thermodynamics

How electricity is replacing combustion as humanity's key tool for mastering the physical world.

Today I want to rant about a technological revolution.

I’ve written a lot about things like the rise of batteries, the triumph of green energy, and other technological revolutions happening in the 2020s. But many of these developments are connected; I see them as visible protrusions of a shift so deep and fundamental that it’s almost hard to describe it. It’s about a shift in which fundamental physical processes human technology as a whole is based on.

I remember a time when I was a teenager, watching the cartoon show Robotech with my friends (it was many years after its initial release; I’m not that old!). In the show there was a secret super-powerful energy source called “protoculture”. I remember one of my friends asking “How do you actually get energy from protoculture? And another friend said “Well, first you use protoculture to boil water into steam, then you use it to turn a turbine…”

We all laughed, but the joke was deeply rooted in technological reality. To this day, most power sources — including nuclear power — basically just heat up water, which turns it into steam, which pushes some sort of a wheel, which either A) turns some gears that make a machine run, or B) turns a magnet that generates an electrical current. For fossil fuel power sources (although not for nuclear), this involves combustion — the rapid release of heat from chemical reactions.

Combustion is one of humanity’s two main methods for extracting and transporting energy. Understanding how to harness combustion was probably the most important technological revolution in human history. The energy provided by coal-powered steam engines, and then by oil-powered internal combustion engines, was what allowed the creation of mechanized agriculture, modern manufacturing, rail transport, cars, trucks, modern shipping, powered flight, and most of the things that raised humanity up out of the muck of abject poverty where we started.

But a second technological revolution was underway at the same time, which also changed the face of our world. This was electricity — the ability to move electrons through conducting materials.

Electricity and combustion are complementary — for example, when you burn coal to boil water to turn a turbine to turn a generator that creates electricity. And of course both rely on some form of chemical potential energy — a gas tank, a battery, etc. —to transport stored energy from place to place.

But ultimately these are two very different ways of moving energy around. Combustion happens in a disorderly rush, as rapid chemical reactions release heat in an uncontrolled fashion. Electricity is a far more stately and controlled process, pushing electrons deliberately through wires and other conducting materials. To understand combustion, you need to understand the physics of random motion; to understand electricity, you need the more precise physics of how electromagnetic fields move charged particles around. The two people pictured at the top of this post, James Clerk Maxwell and Rudolf Clausius — worked out some of the key theories of electrodynamics and thermodynamics, respectively.¹ Those were two of the greatest and most important intellectual triumphs in human history.

Often, electricity and combustion accomplish two different purposes. Combustion, which releases energy very quickly and relies on very dense energy storage mediums (e.g. gasoline), has long provided the “oomph” to make vehicles go. But electricity, with its capacity for fine control, is what we use to power our computers, radios, and other electronic instruments. And because pushing electrons in a nice orderly line is more efficient than releasing energy as heat, electricity is better for some applications like lighting our houses. So for a century and a half, combustion and electricity have largely existed side by side. One offered power and portability; the other, precision.

But there have been a few times throughout history where electricity and combustion got into a little fight. In the early 20th century, the big question was whether factories would run on steam power transmitted mechanically through systems of gears, or on electric power delivered through wires. At first, steam won out, because it was cheaper — burning fuel to turn a bunch of gears is more efficient than burning fuel to create electric current to turn a bunch of gears.

Eventually, though, as the economist Paul David has documented, manufacturers figured out how to use electricity’s precision to do things they could never do with combustion alone. They could bring power to a bunch of small independent workstations instead of having everyone working on one giant assembly line. This let them use power only when needed, and only in precise amounts. It also gave production engineers much more flexibility in rearranging factories to optimize production processes. The result was a tremendous, long-lasting boom in manufacturing.

Another little dust-up between combustion and electricity was in the automotive space. A lot of people tried to make and sell battery-powered cars in the early part of the 20th century. Ultimately, the greater power of internal combustion engines, and the high energy density of gasoline and diesel, doomed EVs for a century.

So anyway, electricity and combustion coexisted for a century. But then a few things changed, which significantly increased electricity’s advantages and shored up its weaknesses.

First, a new technological revolution entered the scene — semiconductors. Semiconductors allow us to generate electric power without combustion or other heat-based methods, because they allow us to capture energy directly from solar radiation. Blowing things up and burning things and boiling things, with all the attendant wastage of energy via the randomness of heat, is no longer a necessary step in the process. You can just go straight from natural energy sources to electric currents.

Semiconductors also allowed electricity to improve on its key strengths. It allowed the creation of computers, which can take much greater advantage of electricity’s amazing precision. Computerization allows electric power to be used in an even more targeted and efficient manner than before. A key example is the creation of MEMS (also a semiconductor technology), which allows precision control of drones via software.

Another key example is the brushless electric motor, which uses circuitry to control the currents in an electric motor through electromagnetic fields instead of mechanical devices. Brushless motors are much more efficient, powerful, durable, and easier to maintain than older motors. In any case, there are many more examples besides these two.

Those excellent new motors were key, because they allowed electric power to leverage another big benefit of precision — efficiency. In an internal combustion engine, or in any combustion technology, a lot of energy is lost to heat. Brushless electric motors can transmit energy more precisely between the moving parts using electromagnetic fields, without having to blast hot gases randomly in every direction.

The other big technological shift was improvements in battery chemistry — most importantly the switch to lithium-ion batteries, but also other things like better electrolytes. This made batteries capable of storing much more energy for a given amount of weight or volume, and it also made them able to release their energy faster — i.e., it made batteries more powerful.

The revolution in batteries also makes it easier to take advantage of electricity’s third advantage — storability. No physical process is fully reversible in the thermodynamic sense, of course, but batteries come a lot closer to that ideal than combustion. You can put energy into a battery and take it out again with only modest losses, while putting combustion products back together to synthesize gasoline or methane is never going to be economic.

In other words, two new technological revolutions shored up electricity’s fundamental weaknesses — low power and low energy density — while expanding on its fundamental strengths of precision, efficiency, and storability.

Combustion technologies, in contrast, have seen relatively modest gains in recent decades. Combustion saw a fantastic flowering of innovation in the 19th and much of the 20th century — better materials and better designs to contain and harness explosions and heat more safely and efficiently. But this efflorescence of innovation probably ended up picking much of the low-hanging fruit in the field. And combustion technology was also hampered by a large and persistent increase in the price of one of its major inputs: oil.

And that’s not even mentioning climate change.

As a result, we’re starting to see electricity become competitive in many of the applications where combustion easily won out in past decades. Solar power is taking over from fossil fuel combustion at an accelerating rate. Batteries are replacing internal combustion engines in cars, also at an accelerating rate. Battery-powered drones are quickly becoming much more important in warfare. Heat pumps are improving to the point where they’re able to challenge combustion-based heating. Battery-powered stoves, ovens, dryers, and other appliances will be both more powerful and cheaper than their gas-burning equivalents.

Nor is this change complete. There’s plenty of scope for both batteries and solar panels to get even better, with the potential introduction of solid-state batteries, alternative battery chemistries, and perovskite solar cells. Meanwhile, continuing progress in AI and other software will only increase the precision with which electric power can be targeted in various devices.

In other words, thanks to some assists from the semiconductor revolution and from big chemistry breakthroughs, electromagnetism is increasing its importance at the expense of combustion. Electrodynamics ran a tight race with thermodynamics for a hundred years, but it’s finally starting to pull ahead.

Source: RMI

I think people still don’t appreciate what a world-changing event this is. The number of basic physical processes that can be harnessed in our Universe is very small. Other than electricity and combustion, humanity really has very few tricks for manipulating the physical world. So when one of these basic control methods suddenly gets much, much better, to the degree where it starts to displace the other, it’s a big deal. It reaches into almost all the major topics I’ve been writing about over the last few years — the Abundance Agenda, competition with China, industrial policy, and so on.

Obviously the biggest effect is going to be an age of abundance. The stagnation of combustion meant a stagnation in energy use and (probably) in productivity as a whole. But electrical technology did not stagnate, and now electricity has finally caught up to the point where it can just replace combustion in a whole lot of physical technologies, and potentially accelerate productivity growth again.

But there are also going to be important competitive effects, at the level of companies and at the level of whole nations and alliances of nations.

One of the biggest effects right now concerns the relative economic power of China and the developed democracies (the U.S, Europe, Japan/Korea/Taiwan, etc.). The developed democracies all built their prosperity on the old traditional mix of combustion and electricity. The U.S. (and the USSR) built the world’s best jet engines, while Europe and Japan built the world’s best internal combustion engines for cars and other vehicles. China tried to catch up, but never managed to build a competitive traditional automotive or aerospace industry.

The reason is that combustion technologies are very hard to transfer — because combustion is very hard. Containing an explosion in a metal device safely and sustainably, while harnessing the explosion’s energy efficiently, is inherently an incredibly difficult task. It requires an untold number of metallurgical and geometric tricks that are distributed among the personnel of companies like Boeing, Toyota, and Volkswagen.

Electric technology is easier — electric motors have many fewer moving parts than engines, and because you don’t have to contain an explosion there’s a lot less fancy metallurgy involved. But just as importantly, electric technology represents a very different set of tricks than combustion does — which means Chinese companies are starting on a level playing field with their established rivals.

Actually, it’s not a level playing field — it’s tilted in China’s favor. As Clay Christensen wrote, big companies often have trouble adapting to the emergence of cheaper new technologies that undermine their established business models, allowing newcomers to disrupt them. BYD and other Chinese EV makers are definitely in the process of disrupting incumbents like Toyota, Volkswagen, and Ford, which are shifting away from ICE tech far more slowly than their Chinese rivals (or trying to experiment with dead-end ideas like hydrogen cars). Meanwhile, America’s Air Force may cling to its traditional strength in big fast jet aircraft, while China becomes king of versatile low-altitude drones.

Meanwhile, China’s political-economic system allows it to muster both the capital and the political will to make very rapid changes to its energy generation mix — building out solar at a tremendous pace, and electrifying much of their economy.

Source: RMI

In sum, the world’s developed democracies, including both their companies and their government institutions, were built for a world divided between combustion and electricity. Now that electricity is overtaking combustion in more and more ways, the world’s old powers have been disrupted. China is the country of electricity — the country of the electric motor, the battery, the solar panel, and the drone. It’s hard not to see that as a winning technological platform. Xi Jinping’s list of key technologies of the future might sound long and unfocused, but in practice a lot of it is just electricity.

Now, that might sound like a scary bad thing, because China is not friendly toward America or its allies. And many aspects of it are indeed quite worrying. But it’s not only China that can disrupt the old powers by harnessing the power of electricity — other developing countries can do it too. That’s why it’s so exciting to see up-and-coming nations like Bangladesh and Vietnam pull ahead of the U.S. and Europe in terms of electrification:

Source: RMI

Meanwhile, big developing countries like India have been building solar power rapidly. It would be unambiguously great to see the countries of the developing world become competitive in new electric technologies, as well as getting more abundant power and transportation.

My worry is that the U.S. and other developed countries won’t follow this approach, and will cling to increasingly outmoded combustion-based approaches. I’m not sure they’ll realize how broad and sweeping the shift is, or how unlikely it is to be reversed. The rise of electricity from “an adjunct to combustion” to “the near-universal medium of energy generation, storage, transfer, and extraction” is one of the most important technological shifts of our time, with the rise of AI and biotech as the only competitors. It’s time we started conceiving it as such.

Update: Sam D’Amico has a great short thread about the four key innovations that allowed the world to electrify. They are:

• Better permanent magnets (enabling better electric motors)

• Better power transistors

• Cheaper batteries

• Purpose-built computer chips for EVs and drones

Here’s a cool graph he shows, demonstrating how much better new magnets are relative to old ones:

Note that the recent “wonder materials” for magnets were invented in Japan and the U.S., but that their manufacture is now mainly in China due to that country’s dominance of rare earth supplies.

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1. I was also going to include pictures of Michael Faraday and Nicolas Léonard Sadi Carnot, but that would have made the image a little too crowded. Just for fun I also could have included a picture of Lord Kelvin, who made significant contributions to both electromagnetic theory and thermodynamics.