All of the earth’s coal was created during the Carboniferous Period 400 million years ago, when a high level of carbon dioxide trapped the sun’s energy, warming the planet and providing copious carbon as raw material for plants and sea algae. The land and seabed were covered with a dense mat of dead organic matter built up over millions of years, extending thousands of feet deep in some areas. When coal was used to power steam engines, the first usage was to pump water out of coal mines, therefore accelerating the rate of extraction. Oil has an energy density double that of coal. A single barrel of oil produces the same amount of energy as a man doing hard manual labour for 10 years. Buckminster Fuller used the metaphor of an energy slave. It would take an energy slave pedaling hard on a bicycle to keep a hundred-watt bulb going. An average American consumes about 24 barrels of oil a year, and therefore requires 240 hundred energy slaves to sustain his lifestyle. At our current rates of usage, we are burning up about 14,000 years’ worth of fossilized sunshine every single day.