It is not necessary to explain the process by which algae through millions of years of geological time and chemical reactions become fossil fuels such as oil, natural gas and coal. It is important to explain, however, why these fossil fuels have become the most vital resources in the world today. Our modern-day lives depend on these fossilized resources so much. More important, we should reflect on how we consume in just one year what it took nature over 5 million years to produce. Since 1860, geologists have discovered over 2 trillion barrels of oil and since that time, we have consumed over half that amount.
Unlike petrochemicals (usually a collection of well-defined pure chemical compounds), petroleum products are complex mixtures. According to the composition of crude oil, refineries can produce different types of petroleum products. The items produced from crude oil is astounding and number in the thousands. In fact, scientists have already identified some 500,000 different uses for oil. Currently, the global economy has an ever increasing demand and an ever increasing need for this resource. Our world is so dependent upon it and other fossil fuels that even the smallest disruption in supply can have devastating consequences. For example, our cities are completely fossil dependent. We construct our city roads from asphalt, a petroleum product. The roofs of our homes are a petrochemical product. Most cities are commercial and residential based and require many people to drive long distances. Also, suburban sprawl forces many people to drive to work, school, and stores. Further, large areas of the world would be uninhabitable without heating in the winter or air conditioning in the summer. Fossil fuels are also key ingredients in the creation of plastics and polymers used in the manufacture of computers, entertainment equipment and clothing. In addition, our modern day systems of agriculture are heavily dependent upon fossil fuels, as well as, hospitals, aviation, public transportation and water distribution systems.
In the early years, oil was easy to find and extract. Geologists found enormous deposits of oil, natural gas and coal. At that time, the US produced more oil than any other country which enabled it to become an industrial superpower. However, once an oil well begins producing, it is only a matter of time before it enters a decline. Typically, it takes about forty years for a well to reach its peak of production. Afterward, it enters a permanent fall. In the 1950s, M. King Hubbert, a geophysicists for Shell predicted that America’s oil production would reach a peak by 1970 (40 years after the period of the highest discoveries of oil in US history). Almost no one believed him. But by 1970, US oil production reached a peak and entered into a permanent decline. From that point on, America would become dependent on imported oil. The negative consequences of this event made the US vulnerable to supply disruptions such as the oil shocks of 1973 and 1979. Despite advances in technology, the decline in American oil fields continued. Even with the oil discovered in Alaska and the Gulf of Mexico, neither area comes close to supplying America’s demand for required energy.
Several factors make oil unique. For example, at room temperature it is a liquid, it is also easy to transport and it is usable in small engines. Oil produces energy which equivocates into the capacity to do work. Some fuels contain more energy than others – this is called energy density. Of all fossil fuels, oil is the most critical. But to acquire energy, you have to use energy. The challenge is to use small amounts of energy to find and extract large amounts of energy. This is EROEI or the return on energy invested. One characteristic that makes oil so important is one bottle of oil is equivalent to almost three years of human labor.
The history of conventional oil serves as a good example. First, the easy to extract, high quality crude was discovered and pumped. Oil producers spent the equivalent of one barrel of oil to find and extract one hundred barrels of oil. As the easy to find oil started to decline, exploration moved into deep waters and distance countries using ever increasing amounts of energy to find and extract oil. Today, much of the oil found is heavy or “sour” crude and it is expensive to refine. As a result, the return on investment is now as low as one barrel of oil to just ten barrels of oil found and extracted. Consequently, if the energy required to find and extract oil is more than the oil discovered, it is not worth the effort. It is possible to convert one fuel source into another. But each time this occurs, the original source loses energy.
Also, there are unconventional sources such as tar sands and shale. Tar sands are found mostly in mainland Canada and two thirds of all shale is in the United States. Both of these fuels can be converted to “synthetic” crude oil, but this requires large amounts of heat and fresh water reducing the EROEI to as low as 5 barrels to that of 1 and 1/2 barrels. And shale is an exceptionally poor fuel.
Finally, the world consumes about 30 billion barrels of oil per year equal to one cubic mile which contains as much energy as fifty-two nuclear power plants working for the next fifty years. Coal exists in vast quantities, but global coal production may peak before 2040. More important, much of the high quality anthracite coal is gone leaving lower quality coal that is less energy dense. Natural gas is often found alongside oil and coal, however it needs high energy prices to be profitable. Even with conventional gas, there may be a peak in global natural gas production by 2030. After 2080, all these vital resources may be in a state of perpetual decline.
Ranken Energy. (2010). What’s Made from from Crude Oil? accessed: 15 October 2016. http://www.ranken-energy.com/products%20from%20petroleum.htm; Free Documentaries. (2014). Energy…Where do we Stand? accessed: 4 October 2016. https://www.youtube.com; Wikipedia. (2016). Petroleum Product. accessed: 15 October 2016; https://en.wikipedia.org.