Numbers Don't Lie: 71 Stories to Help Us Understand the Modern World

by Vaclav Smil

historical context, the scientific unit of energy is one joule, and affluent economies now consume annually about 150 billion joules (150 gigajoules) of primary energy per capita (for comparison, one ton of crude oil is 42 gigajoules); while Nigeria, Africa’s most populous (and oil- and natural gas–rich) nation, averages only 35 gigajoules. The difference is impressive, with France or Japan using nearly five times as much energy per capita, but the historical comparison illuminates the real size of the gap: Japan used that much energy by 1958 (an African lifetime ago), and France averaged 35 gigajoules already by 1880, putting Nigeria’s access to energy two lifetimes behind France.

The world will soon have 8 billion people (8 x 109), in 2019 its economic output (in nominal terms) was about $90 trillion ($9 x 1013), and it consumed more than 500 billion billions of joules of energy (500 x 1018, or 5 x 1020).

In 1800, less than 2 percent of the world’s population lived in cities; by 1900 the share was still only about 5 percent. By 1950 it had reached 30 percent, and 2007 became the first year when more than half of humanity lived in cities. By 2016, the United Nations’ comprehensive survey found 512 cities with a population greater than 1 million, with 45 of them larger than 5 million and 31 surpassing 10 million. This largest group has a special name: “megacities.”

Besides, why rush to elevate ourselves into the creators of a new geological era instead of waiting a bit to see how long the experiment conducted by Homo sapiens can last? Each of the six elapsed epochs of the Cenozoic era—from the beginning of the Paleocene 66 million years ago to the beginning of the Holocene 11,700 years ago—lasted at least 2.5 million years, including the previous two (the Pliocene and the Pleistocene), and we are now less than 12,000 years into the Holocene. If there is in fact an Anthropocene, it may date no further back than 8,000 years (counting since the beginning of settled agriculture) or 150 years (counting from the takeoff of fossil fuel combustion). Should we manage to be around for another 10,000 years—a trivial spell for science fiction readers; an eternity for modern, high-energy civilization—we should congratulate ourselves by naming the era shaped by our actions. But in the meantime, let us wait before we determine that our mark on the planet is anything more than a modest microlayer in the geologic record.

With little less than 100 gigajoules per vehicle, the 75 million vehicles sold in 2020 embody about 7 exajoules of energy (slightly more than Italy’s annual energy use) and weigh about 100 million tons. New cars thus weigh more than 180 times as much as all portable electronics, but require only seven times as much energy to make. And as surprising as that may be, we can make an even more startling comparison. Portable electronics don’t last long—on average, just two years—and so the world’s annual production of these devices embodies about 0.5 exajoules per year of use. Because passenger cars typically last for at least a decade, the world’s annual production embodies about 0.7 exajoules per year of use—which is only 40 percent more than portable electronic devices! I hasten to add that these are, necessarily,

Bonus point: it would actually work. And there is also a comfort factor. With the outdoor temperature at –18°C (common January overnight lows in Edmonton, Alberta, or daily highs in Russia’s Novosibirsk) and the indoor temperature at 21°C, the internal surface temperature of a single-pane window is around 1°C, an older double-pane window will register 11°C, and the best triple-glazed window 18°C. At that temperature, you can sit right next to it.