There is something to be said for understanding energy in both ecological systems and human social systems, as well as its relation to complex economic and political systems. This understanding doesn't seem to be common knowledge and yet the basics of energy seem to be within the grasp of most people. This entry is aimed at providing a basic overview of energy and how energy systems affect our society.
All life depends on energy. Most of that energy comes from the sun (with very little exception). Even though the Earth is 93 million miles from the sun we always have 1,372 watts of energy from the sun per meter hitting the earth. This energy is used for weather systems such as heating the atmosphere and oceans, as well as fueling life by providing autotrophs with energy. As we all learned in biology, photosynthesis is the process whereby plants trap solar energy and chlorophyll molecules turn this into chemical energy. It is because of these autotrophs that us hetrotrophs or consumers can survive. We are locked into a system often called the web of life or food chain which energy is the currency and it is transferred i.e. from green plants to herbivores to carnivores to decomposers. As it is transferred the some of the energy is lost and merely 5-20% of the usable energy can be transferred between members of the food chain. This is why autotrophs account for a much higher percentage of the biomass since they are the energy producers for the rest of the system. If left undisturbed these ecosystems often tend to get to a state of dynamic equilibrium known as climax phase. This means that organisms have adapted themselves to live with relatively constant population levels, to avoid direct competition, and recycling energy as efficiently as possible. In other words they have formed a community. That's all well and good but what does this have to do with human society?
We humans like nearly every other organism are trying to capture solar energy. Although there is much data that shows humans can live as members of the long term climax ecosystems in modern times we have taken more and more of this solar energy acting as a colonizer or invader. Even 60,000 years ago in Australia when humans arrived they used fire to flush out game for hunting, which in turn wiped out the food sources of giant kangaroos, and other large mammals and birds. In fact within a few millennia of human arrival on the island 85% of animals weighing over 100 pounds disappeared. The same kind of trends followed when humans arrived in many new habitats around the earth. However what's really important about this is what happened next. That is that in Australia the Aborigines developed systems of myths, and rituals wherein over hunting was forbidden and fire was only to be used seasonally. They also limited their own population through extended lactation, contraceptive herbs, and even infanticide. In other words they adapted to their surroundings. However this was only after a strategy of takeover had been applied. This strategy of takeover was through tool use in the form of fire. From early in our history most all of our tools were used to gain more access to and get greater amounts of solar energy - or in other words most of our tools have been used for the takeover of ecological systems.
Most of our strategies for takeover come from a culture of agriculture. This is because agriculture is by it's nature a strategy of takeover. Forests are cleared for fields which contain plants only to be used by humans which is a literal takeover of the ecological system which used to provide energy to many different types of organisms. The act of clearing land for use by a monoculture fed on only by humans and their livestock however was not the most startling strategy by which humans seek energy in my opinion. The most startling thing is when humans began to use other humans as tools systematically. This happens through slavery as well as specialization or change to a hierarchical society. Or as David R. Montgomery says in Dirt,
Or Richard Heinberg in The Party's Over,"Class distinctions began to develop once everyone no longer had to work the fields in order to eat. The emergence of religious and political classes that oversaw the distribution of food and resources led to development of administrative systems to collect food from farmers and redistribute it to other segments of society."
"Some humans could capture the energy of others who had been seized in war, putting them to work at tasks too dangerous, dreary, or physically taxing for any free person to undertake voluntarily - tasks such as mining metal ores from beneath the Earth's surface. Those ores were, in turn, the raw materials from which were fashioned the chains and weapons that kept the slaves themselves in bondage. Eventually, metals also came to be used as money, a tool that would become the basis for a more subtle form of energy capture: wage labor. Through the payment of money, humans could be persuaded to give their energies to tasks organized by - and primarily benefiting- others."This use of humans by other humans was a cultural of empire as well. This meant that if you had a larger area with which to trade or often steal resources from you had a better chance of surviving local catastrophes such as earthquakes, floods, or most likely famines. This system is now known as globalization. We now survive mostly off of goods coming from far away. Even an average carrot comes 1,838 miles to get to you. A t shirt may travel 17,000 miles. Neither of them are the most important good to be shipped around the globe though. The most important goods to modern human society are fossil fuels. Fossil fuels are what make this globalization really possible. The reason is simple, they are packed with energy. A fit human adult can sustain about one-tenth of a horsepower, so a human would have to labor more than 10 years to equal the energy of a barrel of oil. Except for maybe John Henry no human can compete with most any modern machine. Why would you hire workers for tasks like agricultural labor, making cars, t-shirts, band aids, and most all consumer goods when you only have to pay for the energy for the labor of a machine which needs no retirement or other benefits?
The new fossil fuel based economy had dreadful effects on society. With fossil fuels being used in farm equipment it allowed one farmer to farm much more land. Cattle could now be shipped via railway to major cities. Throughout the late 19th and early 20th century in the US, cattle often fed on lands that once fed Buffalo that in turn fed Nations of Native peoples. As less people were needed on farms the small farm that was idealized in early US history was almost impossible to keep. There were other reasons though. Soil erosion from farming with the new fossil fueled machinery was a major often caused lower yields as well as the infamous dust bowl of the 1930's.
This came at a time following wheat farming became very profitable because of WWI and price inflation and then very unprofitable as the price collapsed. Farmers had no choice but to plow large acreages in order to get money which led to farming practices that were ruinous. Banks began to seize land and assets from those who could not pay back loans made as the economic depression was setting in. This caused people to migrate to the cities much like English Land Enclosures of the 19th century displacing peasants.
Total population: 17,069,453; farm population; 9,012,000 (est.); farmers 69% of labor force
Total population: 75,994,266; farm population: 29,414,000 (est.); farmers 38% of labor force; Number of farms: 5,740,000; average acres: 147
Total population: 122,775,046; farm population: 30,455,350; farmers 21% of labor force; Number of farms: 6,295,000; average acres: 157; irrigated acres: 14,633,252
1970Now oil is responsible for harvesting crops which also have to be transported by oil to get to you as in the example of the carrot. Fossil fuels have completely reshaped our economy and now our economies are very reliant on fossil fuels. The only problem is that they're a limited resource. According to the International Energy Agency (IEA) world oil production peaked in 2006. Coal is set to peak by 2025. The decreasing supply of fossil fuels with an increase in demand for energy is going to make oil, and coal much more expensive. Some may think what about solar, wind, hydrogen, nuclear, and bio-fuels?
Total population: 204,335,000; farm population: 9,712,000; farmers 4.6% of labor force; Number of farms: 2.780, 000; average acres: 390 http://www.agclassroom.org/gan/timeline/farmers_land.htm
Alternatives to fossil fuel based energy systems exist but, they cannot replace the amount of energy we currently use because of fossil fuels. The main reason can be attributed to a figure known as Energy Returned On Energy Invested (EROEI). First of all keep in mind oil had an EROEI of 100 in 1940, meaning that 100 units of energy were returned for every one invested. By the 1970's the oil EROEI had dropped to 23. Solar photovoltaic can be anywhere from 1.7-10, wind up to 2. Hydrogen is hard to get a real number on but so far it's a net energy loss since it requires fossil fuels to fuel the process to make it. Nuclear plants are about 4-4.5 and bio-fuels about 1.8 at the highest. In other words we're facing a world that in the very near future is going to have more energy demands than can be met. The repercussions this will have on our economy will change our world and force us to change from economies based on continual growth since that will no longer be possible. Our economy will be hampered by the loss of cheap, and easy to get energy to do our work.
So where does this leave us? Undoubtedly although applications of renewable energies could avert a total crisis, although according to the Hirsch report which stated, "Initiating a crash program 10 years before peaking leaves a liquid fuels shortfall of a decade." Prospects of an easy transition don't look good but all is not lost. There are many efforts which can be undertaken to help mitigate the shortfalls in global energy. If we look to Cuba, who after the fall of the USSR, began to grow more and more of its food locally rather than import Soviet grown foods. More than 200 gardens in Havana supply its citizens with more than 90% of their fruit and vegetables. Yields have more than quintupled from 4 to 24 kilograms per meter squared between 1994 and 1999, and currently around a million tons of food per year is produced. This story is well told in the film The Power of Community: How Cuba Survived Peak Oil. This type of food production could help to stem off problems of hunger once oil becomes to expensive to be used to transport consumer goods around the world. In other words globalization will peak and recede since it will become more and more expensive to transport goods.
Possibly the best strategy to be pursued by humans in the near future will be to re-examine the fundamental strategies of controlling energy and using it in our culture especially on the ecological level. Many people such as Bill Mollison have done considerable work showing that much energy is required in order to stop ecological succession with agriculture. Creating forest gardens could both reduce the work load and provide an abundance of food. Not only that but the systems are more drought resistant and contain more biodiversity which is becoming more important with the changes occurring in Earth's climate. We also have to confront that working simply for existence and the gain of others is an immoral practice by which one man purchases your energy to sell it's effect at a greater price. In other words we'll probably have to stop the hyper-individualistic lifestyle led in the US in order to make better decisions based on how it affects the community at large. The future maybe bleak if all we try to do is continue with our same system in place, but the collapse of the fossil fuel economy may help the people to win back the power of production away from corporations, machines, and the super rich that own and finance them.
I hope this helps you wrap your head around the energy and it's effects on society. Although it is a short summary if you're interested I will leave a few links as well as books you may be interested in checking out.
The Party's Over: Oil, War and the Fate of Industrial Societies- Richard Heinberg
Dirt: The Erosion of Civilizations- David R. Montgomery
Twilight in the Desert: The Coming Saudi Oil Shock and the World Economy- Matthew R. Simmons