How the World Really Works: The Science Behind How We Got Here and Where We're Going

by Vaclav Smil

Urbanization and mechanization have been two important reasons for this comprehension deficit. Since the year 2007, more than half of humanity has lived in cities (more than 80 percent in all affluent

call the four pillars of modern civilization: ammonia, steel, concrete, and plastics. Understanding

But it is imperative that we understand the facts of the matter. Only then can we tackle the problem effectively.

extrasomatic

In the Americas and in Australia (lacking any draft animals and any simple mechanical prime movers), all work before the arrival of Europeans is done by human muscles. In

By 1800 a passing probe will record that, across the planet, plant fuels still supply more than 98 percent of all heat and light used by the dominant bipeds, and that human and animal muscles still provide more than 90 percent of all mechanical energy needed in farming, construction, and manufacturing. In the UK, where James

Even by 1850, rising coal extraction in Europe and North America supplies no more than 7 percent of all fuel

But by 2020 more than half of the world’s electricity will still be generated by the combustion of fossil fuels, mainly coal and natural gas.

And by the year 2000 only poor people in low-income countries depend on biomass fuels, with wood and straw providing only about 12 percent of the world’s primary energy. Animate prime movers hold only a 5 percent share of mechanical energy, as human exertions and the work of draft animals are almost completely displaced by machines fueled by liquids or by electric motors.

my calculations show a 60-fold increase in the use of fossil fuels during the 19th century, a 16-fold gain during the 20th century, and about a 1,500-fold increase over the past 220 years.[16]

An average inhabitant of the Earth nowadays has at their disposal nearly 700 times more useful energy than their ancestors had at the beginning of the 19th century.

Robert Ayres has repeatedly stressed in his writings the central notion of energy in all economies: “the economic system is essentially a system for extracting, processing and transforming energy as resources into energy embodied in products and services.”[23] Simply put, energy is the only truly universal currency,

Understanding how the world really works cannot be done without at least a modicum of energy literacy.

As we’ll see, our civilization is so deeply reliant on fossil fuels that the next transition will take much longer than most people think.

This led to what is still the most common definition of energy: “the capacity for doing work”—a

And the advantages of liquid fuels go far beyond high energy density.

megatons

that our dependence on crude oil would grow once the product became more affordable and once it could be reliably delivered on a global scale. The shift from coal to crude oil took generations to accomplish. Commercial

Rudolf Diesel’s

In real terms, crude oil was so cheap that there were no incentives to use it efficiently: American houses in regions with a cold climate, increasingly heated by oil furnaces, were built with single-glazed windows and without adequate wall insulation; the average efficiency of American cars actually declined between 1933 and 1973; and energy-intensive

1970 its production share, combined with the retreat of American extraction (which peaked in 1970), made it impossible to ignore its demands.[46] In April 1972 the Texas Railroad Commission

lifted its limits on the state’s output and hence surrendered its control of the price that it had held since the 1930s. In 1971, Algeria

October 1973, it embargoed all oil exports to the US. On January 1 1974, the Gulf states raised their posted price to $11.65/barrel, completing

a 4.5-fold rise in the cost of this essential energy source in a single year—and this ended the era of rapid economic expansion that had been energized by cheap oil. From

Between 1973 and 1975 the global economic growth rate dropped by about 90 percent, and as soon as the economies affected by higher oil prices began to adjust to these new realities—above all by impressive improvements in industrial energy efficiency—the fall of the Iranian monarchy and the takeover of Iran by a fundamentalist theocracy led to a second wave of oil price rises, from

percent decline in the global rate of economic growth between 1979 and 1982.[47]

More than $30 a barrel was a demand-destroying price and by 1986 oil was again selling at just $13 a barrel, setting the stage for yet another round of globalization—this time centered on China, whose rapid modernization was driven by Deng Xiaoping’s economic reforms and by massive foreign investment. Two generations later, only those who lived through those years of price and supply turmoil (or those, increasingly few, who studied their imp...

but there is a fundamental difference between systems that derive 20–40 percent of electricity from these intermittent sources (Germany and Spain are the best examples among large economies) and a national electricity supply that relies completely on these renewable flows.

Could these new renewables produce enough electricity to replace not only today’s generation fueled by coal and natural gas, but also all the energy now supplied by liquid fuels to vehicles, ships, and planes by way of a complete electrification of transport? And could they really do so, as some plans now promise, in a matter of just two or three decades?

conurbations.

69] If the COVID-19 pandemic brought disruption, anguish, and unavoidable deaths, those effects would be minor compared to having just a few days of a severely reduced electricity supply in any densely populated region,

Notice the key qualifying adjective: the target is not total decarbonization but “net zero” or carbon neutrality.

and China (the world’s largest consumer of fossil

A nuclear renaissance would be particularly helpful if we cannot develop better ways of large-scale electricity storage soon.

In contrast, modern nuclear reactors, if properly built and carefully run, offer safe, long-lasting, and highly reliable ways

Electricity is only 18 percent of total final global energy consumption, and

but the course of decarbonizing modern long-distance transportation remains unclear.

have no readily deployable commercial-scale alternatives for energizing the production of the four material pillars of modern civilization solely by electricity. This means that even with an abundant and reliable renewable electricity supply, we would have to develop new large-scale processes to produce steel, ammonia, cement, and plastics.

And while the US has greatly reduced its dependence on coal—replaced by natural gas in electricity generation—the country’s share of fossil fuels in primary energy supply was still 80 percent fossil in 2019. Meanwhile China’s share of fossil fuels fell

why the global consumption of fossil fuels rose by about 45 percent during the first two decades of the 21st century,

two or three orders of magnitude

few generations ago only a small share of well-fed elites did not have to worry about having enough to eat.

worry about what (and how much) is best to eat in order to maintain or improve their health and extend their longevity, not whether they will have enough to survive.

worldwide share of undernourished people decreased from about 65 percent in 1950 to 25 percent by 1970,

to about 15 percent by the year 2000.

which means that rising food production reduced the malnutrition rate from 2 in 3 people in 1950 to 1 in 11 by 2019.[4]

but the modern world’s most important—and fundamentally existential—dependence on fossil fuels is their direct and indirect use in the production of our food.

Without these anthropogenic energy subsidies, we could not have supplied 90 percent of humanity with adequate nutrition and we could not have reduced

global malnutrition to such a degree, while simultaneously steadily decreasing the amount of time and the area of cropland needed to feed one person.

In two centuries, the human labor to produce a kilogram of American wheat was reduced from 10 minutes to less than two seconds. This is how our modern world really works. And as mentioned, I could have done similarly stunning reconstructions of falling labor inputs, rising yields, and soaring productivity for Chinese or Indian rice. The time frames would be different but the