One of the biggest problems humanity is facing at the turn of the third millennium is the threat of dwindling energy resources. A debate is raging across the globe in which climate change skeptics, peak oil deniers and oil barons cross swords with environmentalists,  renewable energy champions and doomsday prophets.

You could drown in the commotion and conclude there are as many possible outcomes as there are voices. But that isn’t the case. Not really. Two facts govern parties of all colors. Fossil fuels are our biggest source of energy today, supplying 80% of the global energy consumption. And fossil fuels are finite.

Looking at history it can easily be argued that the progress of humanity is closely related to its ability to harness energy. When a people increase their control over an existing energy source -or better yet- tap a new one, innovation leaps forward and the organizational level of a culture becomes more complex. Equally, when the availability of energy dwindles living standards regress rapidly. The anthropologist Leslie White wrote in 1949: “[Thus] we trace the development of culture from anthropoid levels to the present time, as a consequence of periodic increases in the amount of energy harnessed per capita per year effected by tapping new sources of power”. For White the harnessing of energy is the single determining factor that drives the course of history.

Manfred Weissenbacher displays a wider view of history in his book Sources of Power: How Energy Forges Human History (2009). He allows for other factors such as political systems, diseases and ill-decision-making to contribute to the shaping of history. But energy is the main factor. He makes a compelling argument that bodies of power that dominate their surroundings –be that a conquering people, a colonizing nation, or a species shaping its environment to its own needs- always have access to larger amounts of energy than those they subdue.

Energy revolutions

The first energy source available to humans was food. The energy acquired through hunting and gathering allowed the first humans not only to sustain themselves but also  to convert energy into muscle power. Applying that muscle power eventually led to the agricultural revolution that took place 10.000 B.C.E. Instead of living on what the environment provided, the first farmers started to manipulate their habitat. They cleared the land of natural growth and built irrigation canals to water the crops. They planted large-seed grasses such as wheat, maize and rice. It was the first energy revolution because the energy of the sun was captured by the crops and made available to the people tending the crops in the form of food.

The shift from hunting-gathering to farming boosted the available energy enormously. The crops yielded up to four times more food than the farmer needed to sustain himself. The surplus energy released some people of the necessity to work in food production. This allowed for classes of people with specialized occupations such as engineers, priests, warriors and artisans. Farming required a better organization than the foraging  lifestyle. Large numbers of people needed to work together to maintain the irrigation canals. Means of transportation were needed to move building materials. A political class emerged to manage the increasing complexity of society. The new energy source led to the rise of the first civilizations.

With the emergence of a controlled energy source, energy campaigns also came into existence. In search for more land to farm, the agricultural societies chased the roaming bands off the grounds they had been hunting. Their surplus energy made it an unequal fight, the farmers were greater in number and had a specialized warrior class. Before long the foraging peoples where expelled from all arable lands and driven back to the harshest and most uninhabitable of lands.

The second energy revolution takes place when coal replaces firewood and steam driven machines replace muscle power at the end of the eighteenth century. Harnessed energy per capita per year boosts dramatically. Again the increase in energy results in a more complex civilization. Less people have to work in food production and even more specialized professions come into existence. Urbanization and faster means of travel and communication advance innovation in science and technology leading up to the first industrial revolution. Great Britain produced 80% of all coal in the global market. And it was Great Britain who dominated the world.

At the beginning of the twentieth century coal makes way for oil. And again we witness all the familiar characteristics of an energy revolution. Society gets more complex. More specialized jobs. Science and technology boost and the two nations that produce the most oil -the United States and the Russian federation- are the two world powers.

History tells a clear story about how human progress is bound to energy sources.

Decline

But if there is a correlation between the increase in available energy and the rise of a civilization than the reverse must also hold true: a decline in available energy leads to a deteriorating civilization. A sad example of this is the Easter Island. In 1722 the Dutch explorer Jacob Roggeveen was the first non-inhabitant to set foot on the island in centuries. What he saw presented him with an enigma. The island was practically barren. There were no animals larger than rats, there were no trees higher than 10 feet.  The 64 square mile island was mostly grassland. The estimated 2000 inhabitants formed a disorganized society. And yet, lining the coast, there were 200 gigantic stone statues as high as 33 feet, weighing 82 tons. The mystery that Roggeveen couldn’t solve was how these people had been able to erect the images without timber being available to build hauling machines, nor the materials to fabricate ropes. Over the centuries the most fantastic explanations have been proposed including an alien invasion. But in 1996 Jared Diamond, writer of Guns, Germs and Steel, proposed a convincing albeit sad explanation.

In 400 C.E. Easter Island was inhabited by Polynesian settlers. Diamond introduces evidence from pollen analyses that at that time the island was overgrown with a lush subtropical forest. Anthropological and paleontological research shows that the inhabitants lived in abundance. There were a variety of crops and fruits available and different kinds of birds and animals. Moreover, the trees provided timber to built strong seafaring canoes which were used to catch porpoises. And that timber was also used to haul the 82 ton statues across the island to the coastline.The riches of the island enabled those first settlers to develop into a highly organized society. Evidence of the energy surplus is in the statues. As there must have been a lot of people specializing in crafting and moving them. So what happened to this thriving community?

They cut the trees. They cut the trees until there were no more trees to cut.

And when the trees were gone no more canoes could be built to fish. The once fertile soil eroded until only grass could grow. Migrating birds stopped visiting the island and the animals all died out. The organized society deteriorated to chaos and the island population which once was 7,000 or even 20,000 strong dwindled to the 2,000 Roggeveen encountered in 1722. (You can read the entire article here)

Vaclav Smil is a prolific writer about energy sources and its impact on humanity. In his book Energy Transitions (2010) he zooms in on those moments in history when one energy source gradually replaces another. When asked what his reason was for writing the book he answered he aims to get the following point across: “There is only one thing that all large scale energy transitions have in common: (…) they take decades to accomplish, and the greater the degree of reliance on a particular energy source or prime mover, the more widespread the prevailing uses and conversions, the longer their substitutions will take. This conclusion may seem obvious, but it is commonly ignored.“

Photo: Frame from the movie Sunshine