Oil
Crude oil or liquid petroleum is a fossil fuel that is refined into many different energy products (e.g., gasoline, diesel fuel, jet fuel, heating oil). Oil forms underground in rock such as shale, which is rich in organic materials. After the oil forms, it migrates upward into porous reservoir rock such as sandstone or limestone, where it can become trapped by an overlying impermeable cap rock. Wells are drilled into these oil reservoirs to remove the gas and oil.
Status and Contribution
Currently the world consumes 85 barrels of oil per day.
According to the International Energy Agency, Global oil demand will expand by 1.5 million barrels a day or 1.6 percent a year on average in the five years between 2009 and 2013.
Advantages of oil
- Oil is one of the most abundant energy resources
- Liquid form of oil makes it easy to transport and use
- Oil has high heating value
- Relatively inexpensive
- No new technology needed to use
Disadvantages of oil
- Oil burning leads to carbon emissions
- Finite resources
- Oil recovery processes not efficient enough
- Oil drilling endangers the environment and ecosystem
- Oil transportation (by ship) can lead to spills, causing environmental and ecological damage
Some Important Facts
- The world consumes more than 85 million barrels of oil each day. By 2015 the consumption is expected to increase to 99 million barrels per day.
- Fossil fuels such as oil take billions of years to form.
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