Fossil fuel

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Fossil fuels are hydrocarbons formed from the remains of dead plants and animals. The theory that hydrocarbons were formed from these remains was first introduced by Mikhail Lomonosov in 1757. In common dialogue, the term fossil fuel also includes hydrocarbon-containing natural resources that are not derived from animal or plant sources. These are sometimes known instead as mineral fuels. The utilization of fossil fuels has enabled large-scale industrial development and largely supplanted water-driven mills, as well as the combustion of wood or peat for heat.

Fossil fuel is a general term for buried combustible geologic deposits of organic materials, formed from decayed plants and animals that have been converted to crude oil, coal, natural gas, or heavy oils by exposure to heat and pressure in the earth's crust over hundreds of millions of years. [1]

When generating electricity, energy from the combustion of fossil fuels is often used to power a turbine. Older generators often used steam generated by the burning of the fuel to turn the turbine, but in newer power plants the gases produced by burning of the fuel turn a gas turbine directly.

With global modernization in the 20th and 21st centuries, the thirst for energy from fossil fuels, especially gasoline derived from oil, is one of the causes of major regional and global conflicts. A global movement toward the generation of renewable energy is therefore underway to help meet the increased global energy needs.

The burning of fossil fuels by humans is the largest source of emissions of carbon dioxide, which is one of the greenhouse gases that allows radiative forcing and contributes to global warming. A small portion of hydrocarbon-based fuels are biofuels derived from atmospheric carbon dioxide, and thus do not increase the net amount of carbon dioxide in the atmosphere.

A limited resource

Annual carbon dioxide emission broken down into various fuel types during 1800-2000 AD. Shows the increasing rate at which fossil fuels are being consumed.

The principle of supply and demand suggests that as hydrocarbon supplies diminish, prices will rise. Therefore higher prices will lead to increased alternative, renewable energy supplies as previously uneconomic sources become sufficiently economical to exploit. Artificial gasolines and other renewable energy sources currently require more expensive production and processing technologies than conventional petroleum reserves, but may become economically viable in the near future. See Future energy development.


Levels and flows

Levels of primary energy sources are the reserves in the ground. Flows are production. The most important part of primary energy sources are the carbon based fossil energy sources. Oil, coal, and gas stood for 79.6% of primary energy production during 2002 (in million tonnes of oil equivalent (mtoe)) (34.9+23.5+21.2).

Levels (reserves) (EIA oil, gas, coal estimates, EIA oil, gas estimates)

  • Oil: 1,050,691 to 1,277,702 million barrels (167 to 203 km³) 2003-2005
  • Gas: 6,040,208 - 6,805,830 billion cubic feet (171,040 to 192,720 km³) 6,805.830*0.182= 1,239 BBOE 2003-2005
  • Coal: 1,081,279 million short tons (1,081,279*0.907186*4.879= 4,786 BBOE) (2004)

Flows (daily production) during 2002 (7.9 is a ratio to convert tonnes of oil equivalent to barrels of oil equivalent)

  • Oil: (10,230*0.349)*7.9/365= 77 MBD
  • Gas: (10,230*0.212)*7.9/365= 47 MBOED
  • Coal: (10,230*0.235)*7.9/365= 52 MBOED

Years of production left in the ground with the most optimistic reserve estimates (Oil & Gas Journal, World Oil)

  • Oil: 1,277,702/77/365= 32 years
  • Gas: 1,239,000/47/365= 72 years
  • Coal: 4,786,000/52/365= 252 years

Note that this calculation assumes that the product could be produced at a constant level for that number of years and that all of the reserves could be recovered. In reality, consumption of all three resources have been increasing. While this suggests that the resource will be used up more quickly, in reality, the production curve is much more akin to a bell curve. At some point in time, the production of each resource within an area, country, or globally will reach a maximum value, after which, the production will decline until it reaches a point where is no longer economically feasible or physically possible to produce. See Hubbert peak theory for detail on this decline curve with regard to petroleum.

The above discussion emphasizes worldwide energy balance. It is also valuable to understand the ratio of reserves to annual consumption (R/C) by region or country. For example, energy policy of the United Kingdom recognizes that Europe's R/C value is 3.0, very low by world standards, and exposes that region to energy vulnerability, since the United Kingdom, by instance, relies on fossil fuels as its primary source.

Environmental effects

In the United States, more than 90% of greenhouse gas emissions come from the combustion of fossil fuels. In addition other air pollutants, such as nitrogen oxides, sulfur dioxide, VOCs, and heavy metals are produced.

It is not as commonly known that radioactive materials are also produced, mainly uranium and thorium, and released directly into the atmosphere. In 2000, about 12,000 metric tons of thorium and 5,000 metric tons of uranium were released worldwide from burning coal. It is estimated that during 1982, US coal burning released 155 times as much radioactivity into the atmosphere as the Three Mile Island incident.

Environmental regulation uses a variety of approaches to limit these emissions, such as command-and-control (which mandates the amount of pollution or the technology used), economic incentives, or voluntary programs.

Fossil fuel subsidies

In economic terms, pollution from fossil fuels is regarded as a negative [externality] and should be taxed. This 'internalizes' the cost of pollution and makes fossil fuels more expensive, thereby reducing their use and the amount of pollution associated with them. Although European nations do impose some pollution taxes, they also give billions of subsidies to the fossil fuel industry, offseting the taxes.

although taxation may be one opinon on reducing their use its not conclusive by any measure.

See also

External links