Energy is the ability to do work. In a number of ways it is absolutely essential for human existence: from the sun's energy that heats the earth and makes it habitable; to the energy stored in plants and animals that humans consume to keep their bodies running.
Within human society when complexity increases there is a matching
rise in energy use and, as we can see around all around us,
modern civilization is becoming more complex by the day. With increased
energy use mankind has more power to alter the environment around him,
to produce more food, build bigger and better shelters, and devote more
time to leisure. As the anthropologist Leslie White once explained
"Other things being equal, the degree of cultural development varies
directly as the amount of energy per capita per year put to work." Energy = Civilization.
For all but a tiny sliver of mankind's 50,000 year history, the use of
energy has been severely limited. For most of it the only source of
energy humans could draw upon was the most basic: human muscle. The
discovery of fire and the burning of wood, animal dung and charcoal
helped things along by providing an immediate source of heat. Next came
domestication, about 12,000 years ago, when humans learned to harness
the power of oxen and horses to plough their fields and drive up crop
The only other readily accessible sources of power were the
forces of wind and water. Sails were erected on ships during the Bronze
Age, allowing people to move and trade across bodies of water.
Measured in modern terms, these powerful pre-industrial water-wheels couldn't easily generate more than 4 kW of power. Wind mills could do 1 to 2 kW. This state of affairs persisted for a very long time:
"Human exertions… changed little between antiquity and the centuries
immediately preceding industrialization. Average body weights hardly
increased. All the essential devices providing humans with a mechanical
advantage have been with us since the time of the ancient empires, or
even before that."
With less energy use, the world was only able to support a small population, perhaps as little as 200 million at 1 CE, and gradually climbing to ~800 million in 1750 at the beginning of the industrial revolution.
Near the end of the 18th century, in a wave of unprecedented innovation and advancement, Europeans began to unlock the potential of fossil fuels. It began with coal. Though the value of coal for its heating properties had been known for thousands of years, it was not until James Watt's enhancement of the steam engine that coal's power as a prime mover was unleashed.
The steam engine was first used to pump water out of coal mines in 1769.
These first steam pumps were crude and inefficient. Nevertheless by
1800 these designs managed a blistering output of 20 kW, rendering
water-wheels and wind-mills obsolete.
Some historians regard this moment as the most important in human history since the domestication of animals.
Nevertheless, the genie was now out of the bottle and there was no going back. The remainder of the 19th Century saw a cascade of inventions and innovations hot on the steam engine's heels. These resulted from the higher amounts of energy available, as well as to improved metalworking (through the newly-discovered technique of coking coal).
In agrarian societies, untouched by industrialization, the population growth rate remains essentially zero.
Transport was revolutionized by steam-powered boats and trains. Steam
ships (1807) could sail against the winds, and steam locomotives (1804)
could move large quantities of goods 10 times
faster than was previously possible.
Michael Faraday first proved the feasibility of converting mechanical
energy into electrical energy in 1831. By 1872, Thomas Edison had
invented the light bulb, and in 1882 led development of the first commercial power plant, running on coal.
All these new fossil-fuel based technologies unleashed creative energies and allowed an exponential increase in the populations and the standards of living in industrialized states. This economic realignment had enormous negative effects: environmental degradation, inequality, and the empowering of industrialized states to dominate weaker ones.
If the 19th Century was the proving ground for our modern-day
fossil-fuel economy, the 20th Century saw the amplification of those
trends, with exponential increases in energy consumption and rapid improvements in
technology in every field.
Coal consumption grew from a billion tonnes per year in 1910 to nearly
five billion in 1990. Oil surged from 10 million tonnes a year in the
late 1880s to 3 billion tonnes in 1990. Natural gas, which was only economic to use for power generation after the Second
World War, went from two billion cubic feet a year in 1910 to
two trillion in 1990.
The energy historian Vaclav Smil compares the total useful energy
derived from fossil fuels to the primary energy form in pre-industrial
terms and across many parts of the developing world today: biomass. "In
equal sometime during the 1890s… By 1950 commercial energies delivered
about five times as much useful energy as biomass. By 1990 this
difference grew to more than twenty times."
The energy boom allowed the population boom to continue unabated. Global
population was around 800 million in 1750. By 1900, 150 years later, it
had doubled to 1.6 billion. It doubled again about 63 years after that.
By the end of the 20th Century, industrial states were almost fully
adapted to fossil fuels. Coal and natural gas provide the majority of
power generation; oil remains king of transportation, and is essential
in many industrial processes like making plastics and fertilizers.
Nuclear power, biomass and hydro-electric power all made inroads into
the complete dominance of fossil fuels in the world economy, but taken
together, along with all other renewables like wind and solar, they amount to less than a
quarter of global energy use.
Industrialization was centered largely in Europe, the United States,
Canada, Australia and Japan throughout the 20th Century. Towards the end
of that century however almost every other region on the earth began
experiencing industrialization to some extent or other, a development we
will cover more in the following sections.
Now that we have a basic
understanding of how the modern energy economy came to be, in the
following sections we will discuss the results of massively increased
energy use and how closely energy use is intertwined with every aspect of our world today.
"Famous Napoleon I Quotations." Quotes.net. Last modified 12 December 2011.
Grigg, David. Population growth and agrarian change: An Historical Perspective. (Cambridge University Press, 1980), p. 1
"History of U.S. Coal Use," National Energy Technology Laboratory, accessed February 10, 2012,
Mcgrail, Sean. "Sea Transport, Part 1: Ships and Navigation," in The Oxford Handbook of Engineering and Technology in the Classical World, ed by John P. Oleson. (Oxford University Press, 2008), p. 616.
Smil, Vaclav. Energy in World History. (Boulder, Colorado: Westview Press, 1994) p. 187.
Stevenson, David. Cataclysm: The First World War as Political Tragedy. (New York: Basic Books, 2004), p. 8.
World Population to 2300. UN Department of Economic and Social Affairs: Population Division.(New York: United Nations, 2004), p. 5.
Wikander, Orjan. "Sources of Energy and Exploitation of Power," in The Oxford Handbook of Engineering and Technology in the Classical World, ed by John P. Oleson. (Oxford University Press, 2008), p. 136.