PETROLEUM

In 1000 B.C. the Chinese first used oil. Oil was first discovered in the U.S. in 1859 in Pennsylvania and by 1870 oil produced 1% the nation's energy needs. By 1900 the U.S. had 8,000 cars and by 1990 oil contributed 42% the U.S. energy. For the first 60 years of production, oil was refined for kerosene and gasoline was discarded as a waste. The demand for petroleum in the United States is obviously tied to the wide use of automobiles for transportation. The average American spends 440 hours in their car per year. One quarter of the world's cars are in the United States where 40% of households own 2 cars and 18% own three or more. Five percent of the world's gasoline is used by the state of California alone. In 2002, SUVs represented one quarter of the auto sales in the U.S. although they only travel 14 miles per gallon (Blatt, 2005). Driving an SUV for one year for an average American uses as much energy as leaving a refrigerator door open for six years or leaving a television or light on for 28-30 years. The U.S. demand for gas has increased 13% since 1990 (Blatt, 2005). As other countries become more developed, their use of cars is increasing. For example, the number of automobiles sold in China increased 73% in 2003 (Blatt, 2005). In developing nations, the majority of the population do not own cars and depend on public transportation (a bus in Paraguay is depicted below).

Oil (petroleum) reserves are trapped within the earth's crust or beneath the sea floor; rarely is there enough pressure to cause it to gush out and usually it must be pumped. Even after water is added to push oil to the surface of the well, only 1/3 of the oil is typically removed from a well. There are ways of removing the remaining oil (steam & carbon dioxide may be used) but they are expensive; as oil prices increase these may become more practical (this recoverable heavy oil from U.S. sources could supply the country for 7 years).

Petroleum is a mixture of compounds which is refined through fractional distillation-it is separated into its various components. In refining, petroleum is superheated until all its components become gaseous; these components then pass through a long column that provides a range in temperatures; larger hydrocarbons become liquid first and can be drained first. At various levels, liquids are drained, now separated by size: gasoline, kerosene, heating oil, aviation fuel, diesel fuel, lubricating oils. The amount of gasoline can be increased by cracking (large C chains broken to form C6-C8 gasoline molecules) and polymerization (short C chains united to form gasoline-sized chains) (American Chemical Society, 1994).

There is a limited supply petroleum: the American Petroleum Institute and the U.S. Dept. Energy estimate that 80% the reserves will be depleted between the years 2022-2045 (depending on whether demand stays constant or increases). Two thirds of the world's proven oil supplies (and most of the undiscovered oil) resides in 5 countries: Saudi Arabia (25%), Kuwait, Iran, Iraq, and the United Arab Emirates. The U.S. has 3% the world's oil reserves but uses 17 million barrels a day (or, in a year, 30% world's output). The richest 20 countries in the world consume 65% of the world's oil, 80% natural gas, and 50% coal in world; 20% of the world's population uses 66% energy. The United States has 5% world's population but 35% cars and trucks. The distance driven in U.S. equals the distance driven in the rest of the world per year.

Oil prices are often tied to political events: in the 1970s, prices rose 10 fold due to Arab oil embargo in 1973 and the Iranian revolution of 1977. While this caused long lines in U.S., it created debt in developing countries.
How long will oil reserves last? More oil is continually being discovered but the amounts aren't terribly significant. It is estimated that humanity has used more than 875 billion barrels of oil since oil was discovered and about 30.6 billion barrels of oil are used per year. According to the US Geological Survey an estimated 2.6 trillion barrels remain to be used, including both known reserves (1.7 trillion barrels) and undiscovered reserves (900 billion barrels). At current rates of consumption, known reserves will last another 40 years although this may decrease as world energy consumption increases. It is thought that the current rate of oil production is close to the peak production which can be achieved. Although studies vary, it is thought that peak global oil production will be reached prior to 2035 (if it has not already passed) (Demirbas, 2008; Lattin, 2007).

During the period of 1977-91 in the U.S., 5 billion barrels of oil supply were discovered vs. the 92 billion used while in the world, 91 billion barrels were discovered vs. 221 billion barrels used. The U.S. has used 40% of its original reserves; we could support ourselves for only 10 years on our own supply. As oil prices increase, reserves which are presently not economical to recover may provide additional supplies.
In 2003, the world used 77 million barrels of oil per day of which 20 million barrels were used by the U.S. Although America does produce oil, the amount of this oil is declining. In 1973, American production totaled 9.2 million barrels/day while in 2003 the amount had fallen to 5.7 million barrels/day. Throughout the world, the amount of new oil discoveries is declining (from 470 million barrels during the period of 1950-1960 to 110 million barrels during the period of 1990-2000) (Blatt, 2005).

There are other sources of petroleum and gas:
a) oil shale: Petroleum can be removed but it is costly (U.S. pilot projects have been abandoned; the world's largest oil shale deposits are in the U.S.). After the rock is crushed, waxy hydrocarbons can be vaporized and collected.
b) tar sands; The largest deposits are in Canada where they supply 12% Canada's energy. They could meet U.S. needs for 3 months at 2-3x present cost. Extracting both these forms produces a great deal of environmental contamination and uses large quantities of water.
c) Natural Gas: A number of the smaller hydrocarbons are gases at room temperature. Natural gas is a mix of these hydrocarbons: 50-90% methane, also ethane, propane, and butane. Gas burns hotter and produces less air pollution than any other fossil fuel. It is more efficient as well: 75% potential energy in petroleum and coal lost while only 30% of natural gas's energy is lost. Natural gas provides 24% world's consumption, after oil and coal. The former U.S.S.R. contains 40% of the world's proven reserves while the U.S. has 6%. Since natural gas is difficult to ship, it is often simply burned as a waste at oil refineries. The U.S. consumes 27% of the world's natural gas (Blatt, 2005).