Why is gasoline so cool?

So we take crude oil and we turn it into gasoline. Why is gasoline so cool, and why is the United States so dependent on gasoline, diesel fuel and jet fuel? It's because gasoline contains an incredible amount of energy per gallon. When you burn gasoline with plenty of oxygen, all the carbons and hydrogens in gasoline combine with oxygen. You get carbon dioxide (from the carbon atoms in gasoline), water (from the hydrogen atoms) and lots and lots of heat. How much heat? If you took a 1,500-watt space heater or hair dryer and left it on full blast for a full 24-hour day, that's about how much heat is in a gallon of gas.

Or here is another way to think about it. If it were possible for human beings to digest gasoline, a gallon would contain about 31,000 food calories. The energy in a gallon of gasoline is equivalent to the energy in about 110 hamburgers. If you could "eat" gasoline, then gasoline contains enough "food energy" to last you about 20 days.

Image courtesy © BP p.l.c. Oil rig

You may be wondering why we all haven't converted over to electric cars and trucks. It's because gasoline contains so much energy per gallon. When you pump 20 gallons of gas into a car, it's like feeding your car 720 kilowatt-hours of electricity. If you were to plug an electric car into a typical house outlet -- an outlet big enough to power a 1,500-watt space heater -- it would take 20 days to get the same amount of energy out of that outlet as there is in 20 gallons of gas. It only takes about five minutes to pump the gas. Twenty days versus five minutes is a huge difference. That is why gasoline is so cool.

Oil Rigs and Derricks To drill for oil either on land or in the ocean, you use a drilling rig. The basic idea behind a drilling rig is to use a giant, spinning drill bit to drill deep into the earth. Each hole can be miles into the ground and up to a foot in diameter. To accomplish this, you need two things. First you need a spinning bit that can carve into rock. Then you need a way to get all of the pulverized rock out of the hole. Both of these needs are handled by a long piece of pipe called the drill string. At one end of the drill string is the bit. At the other end are the turntable and the kelly. The kelly is a four-sided or six-sided piece of pipe that the turntable can grab. The turntable spins the kelly, which spins the drill string, which spins the bit. Since the drill string is a pipe, it is easy to pump fluid into the hole. This fluid is called mud, and it contains water, clay and chemicals. The mud flushes the pulverized rock out of the hole and sends it back up to the surface. Image courtesy © BP p.l.c. Oil drill Above the hole is a derrick, a tall tower that acts like a crane. Every 30 feet or so, the crew attaches a new piece of pipe to the drill string. Every so often the crew also needs to pull the entire drill string and bit out of the hole. They need to do this if the bit breaks or if it is time to line the hole with casing. The derrick helps them do this. If the drilling rig is in the ocean, then it is either floating (in deep water) or anchored to the ocean floor (in shallow water). An ocean rig does the same basic thing a land rig does -- the platform is the only difference.