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

by Vaclav Smil

it is impossible to sum up our understanding even within narrowly circumscribed specialties:

such terms as “physics” or “biology” are fairly meaningless labels, and experts in particle physics would find it very hard to understand even the first page of a new research paper in viral immunology.

atomization of k...

America now has only about 3 million men and women (farm owners and hired labor) directly engaged in producing food—people

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.

free energy—energy available for conversions—as the Kampfobjekt (the object

“What an organism feeds upon is negative entropy” (negative entropy or negentropy = free energy).[20]

some of them now generate it 90–95 percent of the time, compared to about 45 percent for the best offshore wind turbines and 25 percent for photovoltaic cells in even the sunniest of climates—while Germany’s solar panels produce electricity only about 12 percent of the time.[33]

Energy is a scalar, which in physics is a quantity described only by its magnitude; volume, mass,

Power measures energy per unit of time and hence it is a rate

but power is simply the rate of energy production or energy use.

an adult man’s basal metabolic rate (the energy required at complete rest to run the body’s essential functions) is about 80 watts, or 80 joules per second;

hydrocarbons refined from crude oil (gasoline, aviation kerosene, diesel fuel, residual heavy oil) have the highest energy densities

1950 the US still produced about 53 percent of the world’s oil; by 1970, although still the largest producer, its share fell to less than 23 percent—and it was clear that the country would need increased imports—while the Organization of the Petroleum Exporting Countries (OPEC) produced 48 percent.

If energy, according to Feynman, is “that abstract thing,” then electricity is one of its most abstract forms.

electricity still supplies only a relatively small share of final global energy consumption, just 18 percent.

annual CO2 emissions from fossil fuel combustion surpassed 37 billion tons in 2019, the net-zero goal by 2050 will call for an energy transition unprecedented in both pace and scale.

12,000 watt-hours per

kilogram),

Li-ion batteries supply less than 300 Wh/kg, more than a 40-f...

electric motors are roughly twice as efficient energy converters as gas turbines, and hence the effective dens...

two decades of Energiewende the share of fossil fuels in the country’s primary energy supply has only declined from about 84 percent to 78 percent:

anthropogenic energy subsidies,

In two centuries, the human labor to produce a kilogram of American wheat was reduced from 10 minutes to less than two seconds.

growth. This is one of the great paradoxical realities of the biosphere and its explanation is simple: nitrogen exists in the atmosphere as a non-reactive molecule (N2), and only a few natural processes can split the bond between the two nitrogen atoms and make the element available to form reactive compounds.[17]

synthesis of nitrogenous fertilizers has undoubtedly been the primus inter pares among agricultural energy subsidies—but

If you want to eat wild fish with the lowest-possible fossil carbon footprint, stick to sardines.

This means that just two skewers of medium-sized wild shrimp (total weight of 100 grams) may require 0.5–1 liters of diesel fuel to catch—the equivalent of 2–4 cups of fuel.

yet another convincing example of small inputs having disproportionately large consequences, not an uncommon finding in the behavior of complex systems:

think of vitamins and minerals, needed daily in just milligrams (vitamin B6 or copper) or micrograms (vitamin D, vitamin B12) to keep bodies weighing tens of kilograms in good shape.

inedible household food waste (including fruit and vegetable peelings, and bones) is only 30 percent of the total, meaning that 70 percent of wasted food was perfectly edible and was not consumed either because it spoiled or because too much of it was served.[65]

(Si is the second-most common element in the Earth’s crust—nearly 28 percent, compared to 49 percent for oxygen)

global production of these four indispensable materials claims about 17 percent of the world’s primary energy supply, and 25 percent of all CO2 emissions originating in the combustion of fossil fuels—and

2020, nearly 4 billion people would not have been alive without synthetic ammonia.