How the World Really Works by Vaclav Smil.
This book is mostly an old guy shaking his head at the follies of youth while describing the realities of providing food and shelter for billions of people. Even though written post-pandemic, left unsaid is that unaddressed policy failures will ultimately be resolved by one or more of the four horsemen.
The proverbial best minds do not go into soil science and do not try their hand at making better cement; instead they are attracted to dealing with disembodied information, now just streams of electrons in myriads of microdevices. From lawyers and economists to code writers and money managers, their disproportionately high rewards are for work completely removed from the material realities of life on earth.
Moreover, many of these data worshippers have come to believe that these electronic flows will make those quaint old material necessities unnecessary. Fields will be displaced by urban high-rise agriculture, and synthetic products will ultimately eliminate the need to grow any food at all. Dematerialization, powered by artificial intelligence, will end our dependence on shaped masses of metals and processed minerals, and eventually we might even do without the Earth’s environment: who needs it if we are going to terraform Mars? Of course, these are all not just grossly premature predictions, they are fantasies fostered by a society where fake news has become common and where reality and fiction have commingled to such an extent that gullible minds, susceptible to cult-like visions, believe what keener observers in the past would have mercilessly perceived as borderline or frank delusion.
The first chapter of this book shows how our high-energy societies have been steadily increasing their dependence on fossil fuels in general and on electricity, the most flexible form of energy, in particular. Appreciation of these realities serves as a much-needed corrective to the now-common claims (based on a poor understanding of complex realities) that we can decarbonize the global energy supply in a hurry, and that it will take only two or three decades before we rely solely on renewable energy conversions. While we are converting increasing shares of electricity generation to new renewables (solar and wind, as opposed to the long-established hydroelectricity) and putting more electric cars on the roads, decarbonizing trucking, flying, and shipping will be a much greater challenge, as will the production of key materials without relying on fossil fuels.
A very high reliability of electricity supply—grid managers talk about the desirability of reaching six nines: with 99.9999 percent reliability there are only 32 seconds of interrupted supply in a year!—is imperative in societies where electricity powers everything from lights (be they in hospitals, along runways, or to indicate emergency escapes) to heart-lung machines and myriad industrial processes.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, and if prolonged for weeks nationwide it would be a catastrophic event with unprecedented consequences.
Annual global demand for fossil carbon is now just above 10 billion tons a year—a mass nearly five times more than the recent annual harvest of all staple grains feeding humanity, and more than twice the total mass of water drunk annually by the world’s nearly 8 billion inhabitants—and it should be obvious that displacing and replacing such a mass is not something best handled by government targets for years ending in zero or five. Both the high relative share and the scale of our dependence on fossil carbon make any rapid substitutions impossible: this is not a biased personal impression stemming from a poor understanding of the global energy system – but a realistic conclusion based on engineering and economic realities.
In contrast to recent hasty political pledges, these realities have been recognized by all carefully considered long-term energy supply scenarios. The Stated Policies Scenario published by the International Energy Agency (IEA) in 2020 sees the share of fossil fuels declining from 80 percent of the total global demand in 2019 to 72 percent by 2040, while the IEA’s Sustainable Development Scenario (its most aggressive decarbonization scenario so far, allowing for substantially accelerated global decarbonization) envisages fossil fuels supplying 56 percent of the global primary energy demand by 2040, making it highly improbable that this high share could be cut close to zero in a single decade.
Certainly, the affluent world—given its wealth, technical capabilities, high level of per capita consumption and the concomitant level of waste—can take some impressive and relatively rapid decarbonization steps (to put it bluntly, it should do with using less energy of any kind). But that is not the case with the more than 5 billion people whose energy consumption is a fraction of those affluent levels, who need much more ammonia to raise their crop yields to feed their increasing populations, and much more steel and cement and plastics to build their essential infrastructures. What we need is to pursue a steady reduction of our dependence on the energies that made the modern world. We still do not know most of the particulars of this coming transition, but one thing remains certain: it will not be (it cannot be) a sudden abandonment of fossil carbon, nor even its rapid demise—but rather its gradual decline.
12Many people nowadays admiringly quote the performance gains of modern computing (“so much data”) or telecommunication (“so much cheaper”)—but what about harvests? 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 relative gains would be similar.
Most of the admired and undoubtedly remarkable technical advances that have transformed industries, transportation, communication, and everyday living would have been impossible if more than 80 percent of all people had to remain in the countryside in order to produce their daily bread (the share of the US population who were farmers in 1800 was 83 percent) or their daily bowl of rice (in Japan, close to 90 percent of people lived in villages in 1800). The road to the modern world began with inexpensive steel plows and inorganic fertilizers, and a closer look is needed to explain these indispensable inputs that have made us take a well-fed civilization for granted.
Machines consume fossil energies directly as diesel or gasoline for field operations including the pumping of irrigation water from wells, for crop processing and drying, for transporting the harvests within the country by trucks, trains, and barges, and for overseas exports in the holds of large bulk carriers. Indirect energy use in making those machines is far more complex, as fossil fuels and electricity go into making not only the steel, rubber, plastics, glass, and electronics but also assembling these inputs to make tractors, implements, combines, trucks, grain dryers, and silos.
But the energy required to make and to power farm machinery is dwarfed by the energy requirements of producing agrochemicals. Modern farming requires fungicides and insecticides to minimize crop losses, and herbicides to prevent weeds from competing for the available plant nutrients and water. All of these are highly energy-intensive products but they are applied in relatively small quantities (just fractions of a kilogram per hectare).14 In contrast, fertilizers that supply the three essential plant macronutrients—nitrogen, phosphorus, and potassium—require less energy per unit of the final product but are needed in large quantities to ensure high crop yields.
Rather than tracing the energy cost of beef (a meat that has already been much maligned), I will instead quantify the energy burdens of the most efficiently produced meat—that of broilers reared in large barns in what have become known as CAFOs, central animal feeding operations. In the case of chicken, this means housing and feeding tens of thousands of birds in long rectangular structures where they are crowded in dimly lit spaces (the equivalent of a moonlit night) and fed for about seven weeks before being taken away for slaughter.28 The US Department of Agriculture publishes statistics on the annual feeding efficiency of domestic animals, and over the past five decades these ratios (units of feed expressed in terms of corn grain per unit of live weight) show no downward trends for either beef or pork, but impressive gains for chicken.
the synthesis, formulation, and packaging of 1 kilogram of nitrogenous fertilizer requires an equivalent of nearly 1.5 liters of diesel fuel. Not surprisingly, these studies show a wide range of totals, but one study—perhaps the most meticulous study of tomato cultivation in the heated and unheated multi-tunnel greenhouses of Almería in Spain—concluded that the cumulative energy demand of net production is more than 500 milliliters of diesel fuel (more than two cups) per kilogram for the former (heated) and only 150 mL/kg for the latter harvest.37
We get this high energy cost, in large part, because greenhouse tomatoes are among the world’s most heavily fertilized crops: per unit area they receive up to 10 times as much nitrogen (and also phosphorus) as is used to produce grain corn, America’s leading field crop.38 Sulfur, magnesium, and other micronutrients are also used, as are chemicals protecting against insects and fungi. Heating is the most important direct use of energy in greenhouse cultivation: it extends the growing season and improves crop quality but, inevitably, when deployed in colder climates it becomes the single largest user of energy.
Capturing such plentiful pelagic (living near the surface) species as anchovies and sardines or mackerel can be done with a relatively small energy investment—indirectly in constructing ships and making large nets, directly in the diesel fuel used for ship engines. The best accounts show energy expenditures as low as 100 mL/kg for their capture, an equivalent of less than half a cup of diesel fuel.42
Between 1900 and the year 2000, the global population increased less than fourfold (3.7 times to be exact) while farmland grew by about 40 percent, but my calculations show that anthropogenic energy subsidies in agriculture increased 90-fold, led by energy embedded in agrochemicals and in fuels directly consumed by machinery.
Can the world of soon-to-be 8 billion people feed itself—while maintaining a variety of crop and animal products and the quality of prevailing diets—without synthetic fertilizers and without other agrochemicals? Could we return to purely organic cropping, relying on recycled organic wastes and natural pest controls, and could we do without engine-powered irrigation and without field machinery by bringing back draft animals? We could, but purely organic farming would require most of us to abandon cities, resettle villages, dismantle central animal feeding operations, and bring all animals back to farms to use them for labor and as sources of manure.
Every day we would have to feed and water our animals, regularly remove their manure, ferment it and then spread it on fields, and tend the herds and flocks on pasture. As seasonal labor demands rose and ebbed, men would guide the plows harnessed to teams of horses; women and children would plant and weed vegetable plots; and everybody would be pitching in during harvest and slaughter time, stooking sheaves of wheat, digging up potatoes, helping to turn freshly slaughtered pigs and geese into food. I do not foresee the organic green online commentariat embracing these options anytime soon. And even if they were willing to empty the cities and embrace organic earthiness, they could still produce only enough food to sustain less than half of today’s global population.
Another choice is to expand the cultivation of leguminous crops to produce 50–60 megatons of nitrogen per year, rather than about 30 megatons as they currently do—but only at a considerable opportunity cost. Planting more leguminous cover crops such as alfalfa and clover would boost nitrogen supply but would also reduce the ability to use one field to produce two crops in a year, a vital option for the still-expanding populations of low-income countries.58 Growing more leguminous grains (beans, lentils, peas) would lower the overall food energy yields, because they yield far less than cereal crops and, obviously, this would reduce the number of people that could be supported by a unit of cultivated land.59 Moreover, the nitrogen left behind by a soybean crop—commonly 40–50 kilograms of nitrogen per hectare—would be less than the typical American applications of nitrogenous fertilizers, which are now about 75 kg N/ha for wheat and 150 kg N/ha for grain corn.
Another obvious drawback of expanded rotations with leguminous crops is that in colder climates, where only a single crop can be grown in a year, cultivation of alfalfa or clover would preclude the annual planting of a food crop, while in warmer regions with double-cropping it would reduce the frequency of harvesting food crops.60 While it might be possible in countries with small populations and plentiful farmland, it would, inevitably, reduce food-producing capacity in all places where double-cropping is common, including large parts of Europe and the North China Plain, the region that produces about half of China’s grain.
Double-cropping is now practiced on more than a third of China’s cultivated land, and more than a third of all rice comes from double-cropping in South China.61 Consequently, the country would find it impossible to feed its now more than 1.4 billion people without this intensive cultivation that also requires record-level nitrogen applications. Even in traditional Chinese farming, famous for its high rate of organic recycling and for complex crop rotations, farmers in the most intensively cultivated regions could not supply more than 120–150 kg N/ha—and doing so required extraordinarily high labor inputs, with (as already stressed) manure collection and application being the most time-consuming.
Even so, such farms could produce only overwhelmingly vegetarian diets for 10–11 people per hectare.
Four materials rank highest on this combined scale, and they form what I have called the four pillars of modern civilization: cement, steel, plastics, and ammonia.
Physically and chemically, these four materials are distinguished by an enormous diversity of properties and functions. But despite these differences in attributes and specific uses, they share more than their indispensability for the functioning of modern societies. They are needed in larger (and still increasing) quantities than are other essential inputs. In 2019, the world consumed about 4.5 billion tons of cement, 1.8 billion tons of steel, 370 million tons of plastics, and 150 million tons of ammonia, and they are not readily replaceable by other materials—certainly not in the near future or on a global scale.
As noted in chapter 2, only an impossibly complete recycling of all wastes voided by grazing animals could, together with near-perfect recycling of all other sources of organic nitrogen, provide the amount of nitrogen annually applied to crops in ammonia-based fertilizers. Meanwhile, there are no other materials that can rival the combination of malleability, durability, and light weight offered by many kinds of plastics. Similarly, even if we were able to produce identical masses of construction lumber or quarried stone, they could not equal the strength, versatility, and durability of reinforced concrete. We would be able to build pyramids and cathedrals but not elegant long spans of arched bridges, giant hydroelectric dams, multilane roads, or long airport runways.
Between 1990 and 2020, the mass-scale concretization of the modern world has emplaced nearly 700 billion tons of hard but slowly crumbling material. The durability of concrete structures varies widely: while it is impossible to offer an average longevity figure, many will deteriorate badly after just two or three decades while others will do well for 60–100 years. This means that during the 21st century we will face unprecedented burdens of concrete deterioration, renewal, and removal (with, obviously, a particularly acute problem in China), as structures will have to be torn down—in order to be replaced or destroyed—or abandoned. Concrete structures can be slowly demolished, reinforcing steel can be separated, and both materials can be recycled: not cheap, but perfectly possible. After crushing and sieving, the aggregate can be incorporated in new concrete, and reinforcing steel can be recycled. Even now, replacement concrete and new concrete are needed everywhere.
land is not a limiting resource, and if we have the know-how to manage water supply, what are the prospects for providing the macronutrients our crops need while also limiting the environmental impact of applying nitrogen and phosphorus? As already explained, the Haber-Bosch synthesis of ammonia made it possible to provide a reactive form of nitrogen, the leading macronutrient, in any desirable quantity.25 We can also provide adequate amounts of the two mineral macronutrients, potassium and phosphorus. The US Geological Survey puts potassium resources at about 7 billion tons of K2O (potassium oxide) equivalent; reserves are about half that amount, and at the current rate of production these reserves would last for nearly 90 years.26
During the last 50 years there have been periodic comments about imminent phosphorus shortages, some even raising the inevitability of starvation in a matter of decades.27 Concerns about wasting a finite resource are always appropriate, but there is no imminent phosphorus crisis. According to the International Fertilizer Development Center, the world’s phosphate rock reserves and resources are adequate to meet fertilizer demand for the next 300–400 years.28 The US Geological Survey puts the world resources of phosphate rock at more than 300 billion tons, sufficient for more than 1,000 years at the current rate of extraction.2
Losses of nitrogen from fertilized farmland (and from animal and human waste) also cause eutrophication, but aquatic photosynthesis is more responsive to phosphorus additions. Neither primary sewage treatment (sedimentation removes 5–10 percent of phosphorus) nor secondary removal (filtration captures 10–20 percent) prevents eutrophication, but phosphorus can be removed by using coagulating agents or by microbial processes, then turned into crystals and reused as fertilizer.33As already explained, the worldwide efficiency of nitrogen uptake by crops has declined to less than 50 percent, and to below 40 percent in China and France. In conjunction with phosphorus, soluble nitrogen compounds contaminate waters and support excessive algal growth. Decomposing algae consume oxygen dissolved in seawater and create oxygen-less (anoxic) waters where fish and crustaceans cannot survive. These oxygen-depleted zones are prominent along the eastern and southern coasts of the United States and along coasts in Europe, China, and Japan.34 There are no easy, inexpensive, and rapid solutions to these environmental impacts. Better agronomic management (crop rotations, split applications of fertilizers to minimize their losses) is essential, and reduced meat consumption would be the single-most important adjustment as it would lower the need for producing feed grains—but sub-Saharan Africa will need much more nitrogen and phosphorus if it is to avoid chronic dependence on food imports.
a temperature rise that would continue for 25–35 years after the launching of a massive global decarbonization effort would present a major challenge for enacting and pursuing such drastic measures. But because there are currently no globally binding commitments that could see any widespread adoption of such steps within a few years, both the break-even point and the onset of measurable temperature declines advance even further into the future. A commonly used climate-economy model indicates the break-even year (when the optimal policy would begin to produce net economic benefit) for mitigation efforts launched in the early 2020s would be only around 2080.