Science & Technology

Civilization Runs on Ammonia, Plastic, Steel, and Cement—for Now

Vaclav Smil’s How the World Really Works offers hope and despair for techno-optimists.


How the World Really Works: The Science Behind How We Got Here and Where We're Going by Vaclav Smil, Viking, 336 pages, $28

For techno-optimists like me, Vaclav Smil's How the World Really Works is something of a downer. But it's rough on the catastrophist crowd too.

Smil has done interdisciplinary scholarship on food, energy, and the environment at the University of Manitoba, and his book is a clear, concise discussion of the material bases sustaining human life and rising prosperity. It opens by analyzing the sources of energy that power the modern world.

As Smil points out, the prosperity enjoyed in modern developed countries would have been unthinkable without the huge increases in energy that have been supplied by burning coal, oil, and natural gas. Until the 19th century, almost all useful energy available to humanity derived from plants: They fueled our heat, they fueled our light, and they fed our muscles and the muscles of our draft animals. Smil calculates that the increasingly efficient use of growing fossil fuel supplies over the past 220 years has led to a 3,500-fold increase in the availability of useful energy.

Put in terms of physical labor, this increased access to energy is equivalent to having 60 adults working nonstop, day and night, for every person on earth. For people living in rich developed countries, it is equivalent of 240 such laborers apiece. "An abundance of useful energy underlies and explains all the gains—from better eating to mass travel; from mechanization of production and transport to instant personal electronic communication—that have become norms rather than exceptions in all affluent countries," Smil writes.

Smil recognizes that climate change is likely to pose significant problems as the century advances. While Smil acknowledges that humanity needs "to pursue a steady reduction of our dependence on the energies that made the modern world," he persuasively argues that the coming transition "will not (it cannot be) a sudden abandonment of fossil carbon, nor even its rapid demise—but rather its gradual decline."

To show the difficulty of transitioning from fossil fuels, Smil points to the Energiewende, Germany's vast buildout of solar and wind energy. This has cost Germans around $400 billion so far, yet the share of fossil fuels in the country's primary energy supply has fallen just slightly, from 84 to 78 percent. In the International Energy Agency's 2020 sustainable development scenario, he notes, even aggressive decarbonization still leaves fossil fuels accounting for 56 percent of primary energy demand in 2040. The U.S. Energy Information  Administration's 2021 International Energy Outlook report projects that the world in 2050 will be consuming more oil, natural gas, and coal than it is using now.

Smil next tackles the realities of food production for nearly 8 billion people. He observes that mid-20th-century predictions of imminent global-scale famines did not come true. In fact, according to the Food and Agriculture Organization, 65 percent of the world population of 2.5 billion people were undernourished in 1950. By 2019, the rate of undernourishment had fallen to 8.9 percent of 7.7 billion people. In other words, the world in 1950 could supply adequate nutrition to 890 million people, and that rose nearly 8-fold to more than 7 billion in 2019.

These increases in agricultural production have occurred in large part because we have substituted fossil fuels for human labor and fertilizers. Smil calculates that farming and fishing consume about 4 percent of recent annual global energy use. Reducing the waste of a third of food, cutting back a bit on meat eating (from 220 pounds per person annually U.S. to 85 pounds per person in France), and ending the use of biofuels would go a long way toward providing adequate nutrition for the world's growing population while reducing humanity's deleterious effects on the biosphere.

Smil then turns his attention to what he calls the "four pillars of modern civilization": ammonia, cement, steel, and plastics.

Ammonia is used as a source of nitrogen to fertilize crops. The world currently produces 150 million tons of nitrogen fertilizers, largely using natural gas as feedstock. Smil calculates that "nearly 4 billion people would not have been alive without synthetic ammonia," thus making the "synthesis of ammonia perhaps the most momentous technical advance in history." While rich countries can cut back on their use of nitrogen fertilizers, African crop productivity remains low because the farmers on the continent currently have access to only 5 percent of the world's supply.

Plastics—the next pillar—are produced using fossil fuel feedstocks. Global production of plastics has increased from 20,000 tons in 1925 to 2 million tons in 1950, 150 million tons in 2000, and 370 million tons in 2019. Smil decries the "irresponsible dumping" of "these diverse and often truly indispensable synthetic materials."

The third pillar is steel, found everywhere from the skeletons of our bridges and buildings to the turbines that generate electricity. The world uses 1.8 billion tons of the metal annually, of which 1.3 billion tons are produced using virgin materials. Making steel uses about 6 percent of the world's primary energy supply.

And then there's the fourth pillar: cement. Humanity consumes 4.5 billion tons of this each year. From their apartment towers to their roads to their sewers, from their bridges to their subways to their airport runways, modern cities are, in Smil's words, "embodiments of concrete." And cement constitutes 10 to 15 percent of concrete's final mass. In 2018 and 2019, Smil notes, China produced nearly as much cement (4.4 billion tons) as the United States did during the entire 20th century (4.56 billion tons).

If the world's poor countries aim to replicate China's post-1990 experience over the next 3 decades, Smil calculates, that would entail a 15-fold increase in steel output, a 10-fold rise in cement production, a doubling of ammonia synthesis, and a 30-fold expansion of plastic manufacture. "Modern economies will always be tied to massive material flows," writes Smil. "And until all energies used to extract and process these materials come from renewable conversions, modern civilization will remain fundamentally dependent on the fossil fuels used in the production of these indispensable materials."

Smil next outlines the history of globalization. He notes its considerable advantages but questions the brittleness of our world-spanning supply chains. He also has an excellent chapter on understanding natural and technological risks. He points out that, thanks to technological progress and rising wealth, global life expectancy has greatly lengthened over the past century and the risk of dying from a natural disaster has massively declined.

Humanity's biggest impacts on the natural world, Smil notes, are agriculture and climate change. He is fairly confident that food production can be intensified and food waste cut, which would leave more land and sea for nature. But given humanity's dependence on fossil fuels, solving climate change will be difficult. Smil is scathingly dismissive of "quantitative fables" that project that decarbonization can be fast, cheap, and easy. He does believe that various reasonable steps—increasing energy efficiency, insulating buildings, reducing food waste, promoting electric vehicle transportation—can slow the rate of future warming. Nevertheless, he notes that "even a tripling or quadrupling of the recent pace of decarbonization would still leave fossil carbon dominant by 2050."

Let me briefly detour here for a bit of techno-optimist special pleading. The costs of solar power have dropped by 80 percent over the past 10 years, although intermittency remains a problem. And if regulatory authorities would get out of the way, safe new nuclear reactors could be sources of cheap and steady electricity. Recent research suggests that the worst-case scenarios for climate change are implausible and that average global temperature is likely to increase by around 2.2 degrees Celsius above the pre-industrial average by the end of this century.

Peak farmland is near, while biotech advances are enabling such resource-sparing products as microbe-fermented milk and cellular meat production in vats. An expanding number of startups claim to be able to manufacture ammonia much more cheaply than the current energy-intensive processes. For example, the Canadian company Hydrofuels says that it can produce carbon-free ammonia at a tenth the cost of conventional ammonia.

The Brimstone Energy startup claims that it can manufacture cement at the same cost using widely available calcium silicate, which contains no carbon, instead of calcium carbonate limestone. Several innovators have recently developed infinitely recyclable plastics and new energy efficient enzymes that break down current plastics into reusable molecules.

On the other hand, when it comes to energy use and carbon emissions, steel production remains a tough nut to crack.

In any case, Smil has delivered both techno-optimists and Malthusian pessimists a sobering dose of realism about the scale, mass, and inertia of the material underpinnings of modern civilization. "A realistic grasp of our past, present, and uncertain future is the best foundation for approaching the unknowable expanse of time before us," Smil concludes. How the World Really Works amply supplies that foundation.