Petroleum

**Petroleum**, (from Greek πέτρα - rock and έλαιο - oil) also called **crude oil**, is a thick and black liquid. It is a natural material mainly made of hydrocarbons. The hydrocarbons come from many billions of ancient phytoplankton. When they die, their bodies sink to the bottom. This formed basins of oil in many parts of the world.

Most petroleum is found by drilling down through rocks on land or off-shore on the continental shelf. Major producers are in the Middle East, the Americas, and Russia. It is the most important world fuel source. It supplies 38% of the world's energy and is also used to make petrochemicals.

Crude oil is a mixture of many different chemicals (mostly hydrocarbons), most of which burn well. It is separated into simpler, more useful mixtures by fractional distillation in oil refineries to give separate chemicals such as gasoline (or *petrol*) for cars, kerosene for airplanes and bitumen for roads. The bitumen gives crude oil its dark black color; most of the other chemicals in crude are slightly yellow or colorless. 

Petroleum can be easily transported by pipeline and oil tanker. Refined petroleum is used as fuels; mainly gasoline (*petrol*) for cars, diesel fuel for diesel engines used in trucks, trains and ships, kerosene fuel for jets and as lubricants.

Petrochemicals:
* alcohols
* antiseptics
* artificial rubber
* detergents
* drugs
* explosives
* food additives
* insecticides
* perfumes
* plastics
* textile fiber

## Problems 
Petroleum resource is limited and non-renewable. Some believe it will run out within 70 years after a peak oil early in the 21st century.
Burning petroleum or other fossil fuel adds the carbon in the oil to the oxygen in the air to create carbon dioxide, which is an air pollutant.  The carbon can be removed from the carbon dioxide by plants.

There is a lot of crude oil left underground. Oil companies and experts quote "reserves" which some people confuse with the actual amount of oil underground. However, as an oil deposit is drained, making more come out of oil wells becomes more difficult and expensive, so "reserves" means the amount that is not too expensive. 

Most of the crude left underground is in the Middle East which is not a politically stable part of the world. Some governments with lots of oil reserves work together through OPEC to keep production low and prices high. People in countries that use oil complain about high oil prices. However, some environmentalists worry about damage being done by using oil as a fuel source (especially global warming) and are therefore happy when prices are kept high so that people use less oil.

## Viable alternatives 
There are none as far as we know. The small amounts of uncertain output from all wind and solar energy will not get near what is needed. The person who has proved this is Simon Michaux, an Australian expert. He has shown that the sum total of alternative energy sources comes nowhere near replacing oil. That is where we are at now.

## Related pages
* Asphalt
* Coal
* Natural gas
* Oil sands

## Other websites 
* US Energy Information Administration - Part of the informative website of the US Government's Energy Information Administration.
* Environmental effects of oil extraction 
* BP Statistical Review of World Energy  
* PetroTalk Portal for petro related Articles, Discussion, Links and more
* Oil, petroleum: Development, production, consumption and reserves 
* World oil consumption  World oil consumption
* *Crude*: 2007 Australian Broadcasting Corporation documentary [3 x 30 minutes] about the formation of oil, and humanity's use of it
* Petroleum crude oil Citizendium

### Data 
* Department of Energy EIA - World supply and consumption
* Department of Energy EIA - Crude Oil and Total Petroleum Imports to USA
* US petroleum prices  - from US Department of Energy EIA
* European Brent prices  since 1987

## References