Oil is processed into various types of fuel, such as kerosene, gasoline and diesel. Basically, the oil is heated at high temperature and the components start to separate.
Each fuel has a certain amount of energy per gallon: Gasoline has 125,000 British Thermal Units per gallon; kerosene has 135,000 BTUs per gallon; and diesel has a little over 138,000 BTUs per gallon. (A BTU is the amount of energy required to raise one pound of water on degree Farenheit at sea level.) These fuels are combusted (burned under high pressure) to do work, such as propel a motor vehicle. The motors that do this work are inefficient and dirty, so much of the energy is wasted as useless heat and there are serious levels of emissions of carbon dioxide (which causes global warming), sulfur dioxide (which causes acid rain) and nitrogen dioxide (which causes fish to suffocate when it eventually washes into rivers and ponds.)
It should be noted that oil is also converted into plastics, which do not have a very high energy content.
Each fuel has a certain amount of energy per gallon: Gasoline has 125,000 British Thermal Units per gallon; kerosene has 135,000 BTUs per gallon; and diesel has a little over 138,000 BTUs per gallon. (A BTU is the amount of energy required to raise one pound of water on degree Farenheit at sea level.) These fuels are combusted (burned under high pressure) to do work, such as propel a motor vehicle. The motors that do this work are inefficient and dirty, so much of the energy is wasted as useless heat and there are serious levels of emissions of carbon dioxide (which causes global warming), sulfur dioxide (which causes acid rain) and nitrogen dioxide (which causes fish to suffocate when it eventually washes into rivers and ponds.)
It should be noted that oil is also converted into plastics, which do not have a very high energy content.