What Would a World with "Unlimited" Energy Look Like?

The Joint European Torus (JET) was in the news yesterday; The New Yorker's recent profile of the fusion industry, as we may now tentatively call it, paints a promising picture of a number of smaller companies making progress on their own fusion reactor designs. Meanwhile the cost of solar photovoltaics and wind power continues to plummet; and a number of next generation nuclear fission projects look to be edging closer to reality (far more than listed here).

With all that in mind it's fun to imagine how a world with "too cheap to meter" electricity might be different from the world we have now. So here are some ideas I've been able to come up with, in no particular order.

Electrofuels

There are a lot of things that require a lot of energy but have to operate untethered from the grid: planes, helicopters, ships, lorries, trains in places where governments can't be bothered to spend the money needed to electrify railways. Because of the low energy density of batteries and the high energy density of things you set on fire, these applications are likely to continue to need to get their energy from storing a combustible fuel in a tank and burning it. We have carbon neutral ways of achieving this right now. The easiest carbon neutral fuel to produce is probably hydrogen. If you run a fuel cell "backwards" it takes in water and electricity and uses the latter to split the former into hydrogen and oxygen. To get back the energy you put in you can either burn the hydrogen to get heat energy or run it through a fuel cell "forwards" to get back electrical energy.

Unfortunately hydrogen comes with a number of downsides. Because it's the smallest possible atom it leaks from most things, and in order to get it to a reasonable energy density it has to be either liquified or compressed. Either process uses up a considerable amount of energy, which wouldn't, in itself, be a problem in a more energy-rich world. But cryogenic fuels are difficult to handle for obvious reasons, and building light containers that are strong enough to store very high pressure hydrogen will probably always be more expensive than building light containers that only need to store fuels at ambient pressure.

Handily it's currently possible to pull carbon dioxide out of the air, split it into carbon and oxygen, and combine the carbon with hydrogen to start stringing together hydrocarbons. The shortest hydrocarbon, and therefore the easiest to produce, is methane. This is immediately a lot more usable than hydrogen. The natural gas we already use is mostly methane, so it would be a drop in replacement for natural gas in what gas infrastructure remained in such a world.

Unfortunately methane is a much worse greenhouse gas than carbon dioxide (though it doesn't stick around in the atmosphere for as long), so using it at scale might not be great for climate change. There would need to be strict regulations around preventing leaks, and flaring gas that needed to be vented. Flaring might seem wasteful, and it is, but in this world it would at least be carbon neutral. In an energy-abundant world this might not be much of a problem though. Longer-chain hydrocarbons that are liquid at ambient temperatures are easier to store, and more energy dense, so if the price difference between these and methane is low there will be few applications that need methane.

Aviation

Surprisingly, extremely cheap electrofuels would barely change the cost of short-haul flights, according to Wendover Productions only $2.50 of the cost of an $80 plane ticket is spent on fuel. The rest goes on airport fees, tax, crew salaries, company overheads, insurance, the amortised cost of the plane itself, and the rest. Fuel costs do start to become a larger percentage of the cost of long-haul flights though. Very long-haul, non-stop flights are desirable, but rare and expensive. This is because over short distances the dominating factor in fuel efficiency is the large amount of fuel burnt reaching cruising altitude, so the more kilometres you can move once you're there, the better. However after about 5000km the fuel you need to carry is heavy enough that fuel efficiency numbers start to get worse, and over very long distances it's cheaper to eat the cost of multiple take offs and refuellings than to load a plane up with all the fuel it needs.

As well as being more continuous, flights might also get faster. Sonic booms—a continuous phenomena heard by anyone underneath a supersonic plane at any time, rather than something that happens only when a plane first breaks the sound barrier—will probably ensure the sound barrier remains a barrier for flights over land, but with dirt cheap fuels the cost of keeping valuable assets and expensive staff tied up on one flight for longer than necessary might start to tip the balance in favour of increasing aircraft speed.

Carbon neutral aircraft aren't necessarily entirely green either. They will still produce NOx gases, which are responsible for smog and acid rain; and water vapour, which is a greenhouse gas in itself. Albeit one that doesn't stick around in the atmosphere for that long. So a sharp increase in long haul flights will likely come with consequences.

Shipping

Big ships run on bunker fuel, a substance that is as unpleasant as its name suggests. Bunker fuel is the low quality dregs of the crude oil refinement process, and as you'd expect it's pretty cheap and nasty. The cheapness means that shipping will probably be the last sector that switches to electrofuels, but the nastiness means that the benefits if and when that happens will arguably be the greatest. Right now the green premium of bunker fuels relative to electrofuels, that is how it costs to buy a given amount of electrofuel energy as a percentage of the cost of buying the same energy in bunker fuel, is about 600%. For comparison the electorfuel green premium for replacing petrol or diesel is about 230-240%, while it's around 300% for jet fuel.

Much as with aviation, the cost of keeping assets tied up on one trip may start to outweigh the cost of increasing speed. And shipping, which has been slowed down in recent years by high oil prices, might start to speed up again.

Carbon Sequestration

Carbon sequestration is another existing, yet energy intensive, technology cheap energy would start to make viable. Everything previously suggested could, in theory, arise as the result of market forces alone. Although waiting for this to happen on its own might be suboptimal to say the least. Carbon sequestration on the other hand benefits the commons rather than anyone in particular. So large scale deployment of carbon sequestration may be necessary, but it will rely on collective action for benefits that aren't immediately tangible, which is notoriously unreliable.

Agriculture

We used to mine guano and transport it around the world to meet our fertiliser needs. But now we use the Haber process to produce ammonia for the same purpose. This is worth doing, but is so energy intensive that it accounts for about 1.4% of the world's carbon dioxide emissions. Very cheap energy should make fertiliser affordable in parts of the world where it currently isn't.

It's conceivable cheap energy would accelerate the greenhouseification of agriculture, making it more reliable and more local. Hot countries could use cheaply desalinated seawater for farming, while Finland could grow avocados in artificially illuminated buildings. If enough agriculture moves indoors then white greenhouses could increase the albedo of the entire planet by a noticeable amount, and this might be no bad thing.

Dictatorships

Electrofuels outcompeting fossil fuels would be mixed news for democracies that make a lot of money from fossil fuels. It would be truly awful news for dictators who use fossil fuel revenues to buy off a small cadre in their country with huge riches so they don't have to tackle the more difficult problem of more equitably enriching their populous. All things being equal, it seems likely that such regimes will be in trouble. Abundant energy might also make other natural resources a less reliable source of income. While it's hard to imagine that demand for batteries will do anything other than increase over the next few decades, an increased viability of electrofuels will probably reduce the need for batteries relative to what it would otherwise have been, and if next generation nuclear power is able to provide the world's baseload power then the current growth in grid-scale battery storage facilities might at some point peter out. The consequence of this will likely be a relative decrease in demand for elements like cobalt and lithium whose supply chains are notoriously dodgy.

The less discussed side of the resource trap is the fact that as well as facilitating the existence of dictatorships, a glut of natural resources can also increase the political turmoil within them. An aspiring dictator in an oil-rich country need only tear through the country's oil fields with a gang of armed men and a satellite phone to gain control of the country's coffers. And unsurprisingly this sort of political "revolution" is far less likely to result in the establishment of another despot than any meaningful political change for the most people. If we're being optimistic we can hope that lower demand natural resources might mean that when freer regimes are established they are less likely to be overthrown.

Spaceflight

Traditionally the overwhelming cost of spaceflight has been building a massive rocket that gets dumped in the sea after a single flight. This began to change with SpaceX's Falcon 9; the majority of it, its first stage, is reusable, and their upcoming Starship is designed to be entirely reusable. If fuels become orders of magnitude cheaper, then building rockets and operations might become the only meaningful expenses left in getting to space. I still find it unlikely that SpaceX's vision of earth-to-earth commercial rocket travel will be viable. For most purposes rocket engines are too powerful for their own good, the vibration and acceleration they produce make for a good thrill ride, but probably aren't a pleasant way of getting about, and no city is likely to want a the noise of a nearby space port. All in all this is a silly idea.

Greener, cheaper spaceflight, one would expect, will mean more spaceflight. Which is great news for telecommunications, science, and space tourists, but might not be such great news for the planet. The pollution caused by rocket engines varies by fuel type, but universally their exhaust gases are so hot that when they come into contact with the troposphere (the lower atmosphere) they will produce NOx gases. Rockets that use RP-1, which is essentially a very expensive jet fuel, produce soot, carbon monoxide and sulphur compounds too. Methalox (methane fuel, oxygen oxidiser) rockets produce CO2 and water vapour, which might not sound bad for fuels that were produced with atmospheric CO2 in the first place, until you consider that gases in the upper atmosphere take longer to be cycled out, so sucking in carbon dioxide at sea level and dumping it into the upper atmosphere is not a fair trade. This is before you consider the fact that water vapour is a greenhouse gas too! So both methalox, and the cleanest fuel, hydrogen (which produces only water vapour and NOx) lose points for that. If you want to know more about rocket pollution I highly recommend this article/video on the topic.

Summary

It's hard to see an abundance of carbon-free energy as anything other than a good thing, and it is a good thing. But much as decreasing rates of death from heart disease will eventually lead to an increase in rates of death from something else, evading a greenhouse gas catastrophe probably means looking forward to the next catastrophe. Even if it's possible to create electrofuels cheaply we'd likely want to reserve their use for only the applications where batteries weren't viable. The non-CO2 pollution they produce might be tolerable on a remote road where there are few other options, but it should not be tolerated in cities or towns. Likewise, a free-market solution to aviation carbon emissions shouldn't make long-haul flights guilt-free, but it might make them low-guilt. For guilt-free flights we would probably have to find some way of scrubbing emissions or sucking pollutants out of the atmosphere, this should be made a lot easier by energy abundance, but we'll have to make a conscious effort to do so.

Thanks to Jack for the conversation that inspired this post.