A recent article in The New Yorker discusses the importance of refrigeration to the development of Rwanda, where cold storage is necessary to reduce rates of foodborne illness and secure more stable income for farmers. The piece demonstrates an inescapable fact about the future of the world: we need to use more energy — a lot more.
There’s probably about 3 million households in Rwanda, and a vanishingly small number have a fridge. A refrigerator uses about 2 kilowatt-hours (kWh) of energy per day, so if we were able to get one into every household, that would add about 2 billion kWh (2 terawatt-hours, or tWh) to Rwanda’s annual energy usage. That’s about as much energy as there is contained in 1 million barrels of oil — and fully one-third of Rwanda’s current primary energy consumption.
Primary energy describes the amount of energy not just in a barrel of oil but in a lump of coal, a gust of wind, a ray of sunshine, or a uranium fuel rod. Energy, in general, is a measurement that describes the capacity of any system—a cigar, a soccer player, a lightbulb—to perform work on its surroundings. A cigar converts chemical energy into heat via combustion; a soccer player transfers kinetic energy to a ball by kicking it; a lightbulb converts electricity into heat and light. The fundamental unit of energy is the joule: roughly, this is the amount of energy required to lift a pencil one foot into the air. Kilowatt-hours are just another measure of energy, in this case about the amount that a medium-sized person might use in running a 10k at an 8-minute pace.
Energy, put slightly more simply, is just a measure of how much stuff is done in the world. Access to more energy means the ability to do more stuff.
And the world needs to do a lot more stuff. Ten percent of people live in extreme poverty, and 85% live on less than $30 per day. In places like Somalia, Nigeria, and Chad, more than one in every ten children die before the age of five. In those countries, pneumonia, which is caused primarily by malnutrition, is among the top causes of death.
What does it take to end malnutrition? One thing that would help is, as the New Yorker notes, refrigeration: massive amounts of fresh food spoil in the developing world. Refrigerators are part of the solution: to fix malnutrition, you need to get food from where it’s grown to where it’s needed while it’s still edible. And in order to get food between refrigerators, you also need refrigerated trucks, which are extremely energy intensive and of which Nigeria, a country of 200 million people, has fewer than 1000 (it needs 25 times as many).
Those trucks will be more useful (and longer-lived) with better roads to drive them on: only about 16% of Nigerian roads are paved. You need energy equivalent to 240 tons of coal to pave 1 kilometer of asphalt, and with the need to do so for 135,000 km of roadway, you’re looking at an energy cost of roughly 2GwH — about as much as a full square kilometer of solar panels produces each day.
Suppose now that the world has done what it takes to address pneumonia as a cause of infant mortality. What next?
Well, then there’s everything else. Just for starters, we need to set up and run the systems that distribute clean water in order to prevent diarrhea, the next-most-common cause of infant mortality across much of the world. This takes energy. It also takes energy to run dialysis machines, school buses, and incubators for preterm babies. It takes energy to boil a pot of water on the stove, to pasteurize milk, and to manufacture antibiotics. It takes energy to build universities, preschools, old folks’ homes, affordable housing, bookstores and art museums, and yet more energy to provide the air conditioning that allows students to focus and the elderly to survive on hot days in a warming world. It takes energy just to grow food: most of the billions of people alive today — and, with any luck, the billions to come — owe their lives to the Haber-Bosch process, which quite literally turns energy into artificial fertilizer for the purposes of growing more food. That process is responsible for about 1% of global energy consumption.
It takes energy to do all this — and we haven’t even gotten to Netflix.
Energy and poverty in a nutshell
The economist Lant Pritchett has argued that, when it comes to reducing poverty, “Economic growth is enough and only economic growth is enough.” In other work, he has supported this claim with the following graph, which demonstrates that economic growth seems empirically necessary for poverty reduction. That is, for any given poverty level, there is some corresponding level of GDP capita such that no country has ever been able to eliminate the former without achieving the latter.
GDP measures (or tries to measure) all the economic activity that takes place in a given country, in a given year. Every time money changes hands, GDP goes up. And every time money changes hands, that’s usually becomes someone is doing something. As we’ve seen, that takes energy. So it shouldn’t come as a surprise that GDP and energy are highly correlated.
But Pritchett’s observation also suggests something important about poverty: you can’t eliminate it without using a lot of energy. As it happens, this is also true of infant mortality— as well as a number of other variables that we might care about:
No country has reduced its rate of extreme poverty far below 1% and barely any has reduced its infant mortality rate below 1 in every 1000 births without using more than 10,000 kWh per capita. Enrollment in secondary school increases steadily with energy use, and so does life satisfaction as measured using the Cantril Scale.
You could be forgiven for thinking that energy, in these graphs, is simply a proxy for GDP and all that it entails. But it would be more accurate to say that both figures get at an underlying reality about people’s freedom to exist in the world: what’s going on is that doing stuff in the world requires energy and is measured as economic activity. This is in line with the capabilities approach first developed by the Indian economist Amartya Sen and the American philosopher Martha Nussbaum. In this view, human welfare is basically about positive freedom: we judge the goodness of the world based on how able we are to thrive in it free from violence, disease, and privation.
A world of Britains
At its core, however, the math here is very simple. In the US, the average person uses 77,000 kWh per year. The average Finn uses only about 58,000 kWh. The Brits, good global citizens, use only about 30,000 kWh on average.
The developed world uses a lot of energy. But the situation in the world’s poorest countries is quite different. The figure is 10,000 kWh for Egypt, 8,000 for Bolivia, and 3,000 for Myanmar. In the Democratic Republic of Congo, average primary energy consumption is only 400 kWh, and it shows: less than half of people in the DRC have access to clean drinking water.
It is possible for the developed world to dramatically reduce energy usage, either by increasing efficiency or by taking drastic measures to limit energy use. And it’s necessary for developing countries to increase their energy use so that they can do more stuff in the world in order to meet basic human needs.
So let’s suppose that both things happen: the energy-guzzling citizens of the West, and the United States in particular, cut their energy use to British levels, tolerating up to a fivefold drop in their energy consumption and dramatically restructuring their societies to accommodate the new normal of energy austerity. People in the Global South increase their usage to the same level in order to finally have the basic necessities of modern life. Now the world is using 30,000 kWh per person for each of 8 billion people on the planet, or about 240,000 TWh per year. That’s twice as much energy as the world currently uses.
Can the world lock in this scenario? Can we double energy usage and then hold steady? There are good reasons to think that we can’t — and that we shouldn’t.
The first reason is that the global population is expected to increase from 8 billion to more 10 billion over the next four decades. This entails a 25% increase in population and, if we want to maintain living standards, a 25% increase in energy consumption.
The second reason is that we have a lot of stuff to do. At the top of the list, of course, is solving climate change. According to the International Energy Agency, it is possible to achieve the Net Zero Emissions by 2050 Scenario, potentially limiting warming to under 1.5 degrees above pre-industrial levels, if we dramatically scale up direct air capture technology. According to the IEA, we need to be removing nearly 1 gigaton of carbon per year from the atmosphere in order to hit this target.
At its most efficient, direct air capture technology seems to use about 1500 kWh per ton of carbon removed from the atmosphere. In order to hit the 2050 target, we therefore need to be using about 1500 TWh per year — 1% of current global energy consumption.
But there is more we can do to mitigate the effects of climate change. As a growing population bumps up against the limits of freshwater supplies in places like Jordan, Libya, the Philippines, and even California, increased access to energy can stop millions of people from parching. At a cost of 1 kWh per cubic meter of seawater, it is the massive energy intensity of desalination that currently prevents it from becoming a reality.
It’s worthwhile to think even bigger still. With enough energy, there are no real limits. We could move heavy industry to space, thereby eliminating pollution, rewilding huge swaths of our planet, and allowing long-threatened animal species to flourish once again. We could do away with highways and instead crisscross the earth with high-speed trains that rocket through underground tunnels, or catapult across the earth in planes powered by clean hydrogen. We could sustainably construct housing and reliably produce nutritious food for every single person on the planet.
What does it take?
It can be done. In the near term, it is conceivable that already-common sources of renewable energy like wind and solar power can meet most of the need. Things would be easier if existing nuclear power technologies were expanded, or at least if we avoided shutting such plants down prematurely.
But the more fanciful world described above—the one in which, thanks to plentiful energy, the world has eliminated want—is possible only with continued innovation. In the long term, the renewables we currently have will hit a ceiling. Every square meter of land with a solar panel on it is a spot that can’t be agriculture, housing, forest, or wetland. There are only so many places you can put a windmill, and only so many rivers to dam. To provide a pathway to a world that uses vastly more energy, we will need advanced geothermal, fusion, space-based solar power, or yet more ingenious technologies that we haven’t even thought of yet.
We shouldn’t scoff at these technologies, or the new possibilities that they open up. A world of dramatically increased energy usage doesn’t need to be a dystopian wasteland, and traditional renewable energy isn’t the only way to get it. After all, a world full of dammed rivers, mesas blanketed with solar farms, and plains speckled with windmills to the distant horizon is hardly one where the footprint of humanity falls lightly.