Unprocessed liquid oil — called crude oil — is not an impressive sight, but it is a very concentrated form of energy. In fact, there is enough energy in one barrel (42 gallons / 159 liters) of crude oil to boil about 700 gallons (2,700 liters) of water.
Oil plays a part even in the simplest and most basic activities. Skateboarding, for example, only really took off with the development of wheels made from an oil-based plastic called polyurethane, which is both tough and smooth.
Soon speculative prospectors known as “wildcatters” were drilling anywhere in the US where there was a hint that oil might be lurking. Many went broke, but the lucky ones made their fortunes by striking “gushers.” Oil from California, Oklahoma, and especially Texas fueled a tremendous economic growth that soon made the US the world’s richest country. As car manufacturers and oil companies prospered, the oil bonanza transformed the country forever.
Within 5 years, there were a quarter of a million Model Ts, accounting to 50% of all the cars in the US. In 1925, still half of all American cars were Model Ts, but by now there were 15M of them. The Model T created the first big boom in oil consumption.
In the 1930s, companies looked for ways to use the oil leftover after motor oil had been extracted. In 1935, Wallace Carothers of the DuPont chemical company used oil to create a strong, stretchy artificial fiber called nylon. Launched in 1939, nylon stockings were an instant hit with young women. During the hardships of WW2, when nylons were in short supply, women often faked nylons by drawing black “seems” down the backs of their legs.
Oil and natural gas together make up petroleum, which is Latin for “rock oil.” Petroleum is a dark, oily substance that is typically liquid, but is can also be solid or gaseous. When it come straight out of the ground as a liquid it is called crude oil if it is dark and sticky, and condensate if clear and volatile (evaporates easily). When solid it is called asphalt, and when semisolid it is called bitumen. Natural gas can be found either with oil or on its own. Petroleum is made entirely naturally, largely from the decomposed remains of living things. Although it looks like a simple gooey mass, it is actually a complex mixture of chemicals. Different chemical groups can be separated out at refineries and petrochemical plants, and then used to make a huge range of different substances.
The surface waster of oceans and lakes are rich in floating plankton. Although far too small to see with the naked eye, plankton are so abundant that their corpses form thick blankets on the seabed.
The buried marine organisms are first rotted by bacteria into substances called kerogen and bitumen. As kerogen and bitumen are buried deeper — between 1,000 and 6,000m, heat and pressure “cook” them. This turns them into bubbles of oil and natural gas. The bubbles are spread throughout porous rock, like water in a sponge. Over millions of years, some of them seep up through the rock, collecting in traps when they meet impermeable rock layers.
A single gas tanker’s tank contains enough energy to meet all the US’s electricity needs for 5 minutes.
As a liquid, its volume is less than 1/600th of its volume as gas.
Most of the oil the world uses is black, liquid crude oil drawn up from subterranean pools. Yet this is just a tiny fraction of the oil that lies below ground. A vast quantity of more solid oil exists underground in the form of oil sands and oil shales. Extracting oil from oil shales and oil sands involves heating them so that the oil drains out. At the moment, this is not really economical, but many experts believe that when crude oil reserves begin to run out, oil shales and oil sands may become our main sources of oil.
In the past, “wildcat” wells were drilled in places where the oil hunters had little more than a hunch that oil might be found. Today, test drilling is carried out in locations where the results of surveying suggest that there is a reasonable likelihood of an oil strike. Even so, the chances of finding quantities of oil or gas that can be commercially exploited are less than one in five.
Platform in the Gulf of Mexico, for example, is the world’s tallest structure, standing some 2,000ft above the seabed. Rigs have to be immensely strong, able to withstand gale-force winds and relentless pounding by huge waves.
Each day, some 30M barrels of oil is on the move. That’s 1.5 times the daily consumption of oil in the entire US, and 15 times as much oil as is used in a day in the UK. To get a picture of just what a huge volume of liquid this is, imagine 2,000 Olympic swimming pools full to the brim with black oil.
Oil is the world’s top energy source, and over 80% of all the oil produced is used to provide energy to keep the world moving. Oil’s energy is unlocked by burning it, which is why it can only ever be used once. A little is burned to provide heat for homes. A lot is burned to create steam to turn turbines and generate electricity. But most is burned in engines in the form of gas, diesel, maritime fuel oil, and aviation fuel for transportation. It takes 30M barrels of oil each day to keep all our cars and trucks, trains, ships, and aircraft on the move.
Most cars run on gas. Trucks and buses, however, run mostly on thicker diesel oil. Diesel engines do not need a spark. Instead, the pistons compress the air in the cylinders so hard and warm it so much that the diesel fuel is squirted into the cylinders it ignites instantly. Diesel engines burn less oil than gas engines and are cheaper to run, but they have to be heavier and more robust to take the extra compression. This makes them slower to speed up than gas engines, which is why they are less popular for cars.
Jet fuel is slighter different from gas, having a higher “flash point” (ignition temperature). This makes jet fuel much safer to transport than gas.
Oil in lipstick acts as lubricant.
Grass gown with the aid of fertilizers made from petrochemicals.
Completed in 1936, the Hoover Dam was for many years the world’s tallest dam, at 221m high. Behind it, in Lake Mead, it holds up the equivalent of 2 years of the Colorado River’s water flow. When operating at full capacity, the Hoover Dam’s station can produce enough electricity to power a city of 750K people.