Fossil fuel

A fossil fuel is a fuel formed by natural processes, such as anaerobic decomposition of buried dead organisms, containing organic molecules originating in ancient photosynthesis[1] that release energy in combustion.[2] Such organisms and their resulting fossil fuels typically have an age of millions of years, and sometimes more than 650 million years.[3] Fossil fuels contain high percentages of carbon and include petroleum, coal, and natural gas.[4] Commonly used derivatives of fossil fuels include kerosene and propane. Fossil fuels range from volatile materials with low carbon-to-hydrogen ratios (like methane), to liquids (like petroleum), to nonvolatile materials composed of almost pure carbon, like anthracite coal. Methane can be found in hydrocarbon fields alone, associated with oil, or in the form of methane clathrates.

"Oil and gas" redirects here. For other uses, see Oil and gas (disambiguation).

Coal, a fossil fuel

As of 2018, the world's main primary energy sources consisted of petroleum (34%), coal (27%), and natural gas (24%), amounting to an 85% share for fossil fuels in primary energy consumption in the world. Non-fossil sources included nuclear (4.4%), hydroelectric (6.8%), and other renewables (4.0%, including geothermal, solar, tidal, wind, wood, and waste).[5] The share of renewables (including traditional biomass) in the world's total final energy consumption was 18% in 2018.[6] Compared with 2017, world energy-consumption grew at a rate of 2.9%, almost double its 10-year average of 1.5% per year, and the fastest since 2010.[7]

Although fossil fuels are continually formed by natural processes, they are generally classified as non-renewable resources because they take millions of years to form and known viable reserves are being depleted much faster than new ones are generated.[8][9]

Most air pollution deaths are due to fossil fuel combustion products, it is estimated to cost over 3% of global GDP,[10] and fossil fuel phase-out would save 3.6 million lives each year.[11]

The use of fossil fuels raises serious environmental concerns. The burning of fossil fuels produces around 35 billion tonnes (35 gigatonnes) of carbon dioxide (CO2) per year.[12] Natural processes can only absorb a small part of that amount, so there is a net increase of many billion tonnes of atmospheric carbon dioxide per year.[13] CO2 is a greenhouse gas that increases radiative forcing and contributes to global warming and ocean acidification. A global movement towards the generation of low-carbon renewable energy is underway to help reduce global greenhouse-gas emissions.

Origin
Since oil fields are located only at certain places on earth,[14] only some countries are oil-independent; the other countries depend on the oil-production capacities of these countries

The theory that fossil fuels formed from the fossilized remains of dead plants by exposure to heat and pressure in the Earth's crust over millions of years was first introduced by Andreas Libavius "in his 1597 Alchemia [Alchymia]" and later by Mikhail Lomonosov "as early as 1757 and certainly by 1763".[15] The first use of the term "fossil fuel" occurs in the work of the German chemist Caspar Neumann, in English translation in 1759.[16] The Oxford English Dictionary notes that in the phrase "fossil fuel" the adjective "fossil" means "[o]btained by digging; found buried in the earth", which dates to at least 1652,[17] before the English noun "fossil" came to refer primarily to long-dead organisms in the early 18th century.[18]

Aquatic phytoplankton and zooplankton that died and sedimented in large quantities under anoxic conditions millions of years ago began forming petroleum and natural gas as a result of anaerobic decomposition. Over geological time this organic matter, mixed with mud, became buried under further heavy layers of inorganic sediment. The resulting high temperature and pressure caused the organic matter to chemically alter, first into a waxy material known as kerogen, which is found in oil shales, and then with more heat into liquid and gaseous hydrocarbons in a process known as catagenesis. Despite these heat driven transformations (which increase the energy density compared to typical organic matter by removal of oxygen atoms),[2] the energy released in combustion is still photosynthetic in origin.[1]

Terrestrial plants, on the other hand, tended to form coal and methane. Many of the coal fields date to the Carboniferous period of Earth's history. Terrestrial plants also form type III kerogen, a source of natural gas.

There is a wide range of organic compounds in any given fuel. The specific mixture of hydrocarbons gives a fuel its characteristic properties, such as density, viscosity, boiling point, melting point, etc. Some fuels like natural gas, for instance, contain only very low boiling, gaseous components. Others such as gasoline or diesel contain much higher boiling components.

Importance
A petrochemical refinery in Grangemouth, Scotland, UK
See also: Fossil fuel power plant

Fossil fuels are of great importance because they can be burned (oxidized to carbon dioxide and water), producing significant amounts of energy per unit mass. The use of coal as a fuel predates recorded history. Coal was used to run furnaces for the smelting of metal ore. While semi-solid hydrocarbons from seeps were also burned in ancient times,[19] they were mostly used for waterproofing and embalming.[20]

Commercial exploitation of petroleum began in the 19th century, largely to replace oils from animal sources (notably whale oil) for use in oil lamps.[21]

Natural gas, once flared-off as an unneeded byproduct of petroleum production, is now considered a very valuable resource.[22] Natural gas deposits are also the main source of helium.

Heavy crude oil, which is much more viscous than conventional crude oil, and oil sands, where bitumen is found mixed with sand and clay, began to become more important as sources of fossil fuel in the early 2000s.[23] Oil shale and similar materials are sedimentary rocks containing kerogen, a complex mixture of high-molecular weight organic compounds, which yield synthetic crude oil when heated (pyrolyzed). With additional processing, they can be employed in lieu of other established fossil fuels. More recently, there has been disinvestment from exploitation of such resources due to their high carbon cost relative to more easily processed reserves.[24]

Prior to the latter half of the 18th century, windmills and watermills provided the energy needed for industry such as milling flour, sawing wood or pumping water, while burning wood or peat provided domestic heat. The wide-scale use of fossil fuels, coal at first and petroleum later, in steam engines enabled the Industrial Revolution. At the same time, gas lights using natural gas or coal gas were coming into wide use. The invention of the internal combustion engine and its use in automobiles and trucks greatly increased the demand for gasoline and diesel oil, both made from fossil fuels. Other forms of transportation, railways and aircraft, also require fossil fuels. The other major use for fossil fuels is in generating electricity and as feedstock for the petrochemical industry. Tar, a leftover of petroleum extraction, is used in construction of roads.

Reserves
An oil well in the Gulf of Mexico
See also: Oil reserves

Levels of primary energy sources are the reserves in the ground. Flows are production of fossil fuels from these reserves. The most important primary energy sources are carbon-based fossil energy sources.

Environmental effects
The Global Carbon Project shows how additions to CO
2 since 1880 have been caused by different sources ramping up one after another.
Main articles: Effects of global warming and Environmental impact of the coal industry

The use of fossil fuels was central to the industrial revolution and over the past few centuries has helped deliver huge improvements to the standard of living across the planet. Nevertheless, the burning of fossil fuels has a number of negative externalities - harmful environmental impacts where the effects extend beyond the people using the fuel. The actual effects depend on the fuel in question. All fossil fuels release CO
2 when they burn, thus accelerating climate change. Burning coal, and to a lesser extent oil and its derivatives, contribute to atmospheric particulate matter, smog and to acid rain.[25][26][27]

Global surface temperature reconstruction over the last 2000 years using proxy data from tree rings, corals, and ice cores in blue.[28] Directly observational data is in red, with all data showing a 5 year moving average.[29]
In 2020, renewables overtook fossil fuels as the European Union's main source of electricity for the first time.[30]

Climate change is largely driven by the release of greenhouse gasses like CO
2, with the burning of fossil fuels being the main source of these emissions. While climate change may have positive effects in some parts of the world, in other parts it is already negatively impacting ecosystems. This includes contributing to the extinction of species and reducing people's ability to produce food, thus adding to the problem of hunger. Continued rises in global temperatures will lead to further adverse effects on both ecosystems and people, with the World Health Organization having stated climate change is the greatest threat to human health in the 21st century.[31][32][33][34]

Combustion of fossil fuels generates sulfuric and nitric acids, which fall to Earth as acid rain, impacting both natural areas and the built environment. Monuments and sculptures made from marble and limestone are particularly vulnerable, as the acids dissolve calcium carbonate.

Fossil fuels also contain radioactive materials, mainly uranium and thorium, which are released into the atmosphere. In 2000, about 12,000 tonnes of thorium and 5,000 tonnes of uranium were released worldwide from burning coal.[35] It is estimated that during 1982, US coal burning released 155 times as much radioactivity into the atmosphere as the Three Mile Island accident.[36]

Burning coal also generates large amounts of bottom ash and fly ash. These materials are used in a wide variety of applications, utilizing, for example, about 40% of the US production.[37]

In addition to effects that result from burning, the harvesting, processing, and distribution of fossil fuels also has environmental effects. Coal mining methods, particularly mountaintop removal and strip mining, have negative environmental impacts, and offshore oil drilling poses a hazard to aquatic organisms. Fossil fuel wells can contribute to methane release via fugitive gas emissions. Oil refineries also have negative environmental impacts, including air and water pollution. Transportation of coal requires the use of diesel-powered locomotives, while crude oil is typically transported by tanker ships, requiring the combustion of additional fossil fuels.

A variety of mitigating efforts have arisen to counter the negative effects of fossil fuels. This includes a movement to use alternative energy sources, such as renewable energy. Environmental regulation uses a variety of approaches to limit these emissions, for examples rules against releasing waste products like fly ash into the atmosphere. Other efforts include economic incentives, such as increased taxes for fossil fuels, and subsidies for alternative energy technologies like solar panels.[27]

In December 2020, the United Nations released a report saying that despite the need to reduce green house emissions, various governments are "doubling down" on fossil fuels, in some cases diverting more than 50% more of their Covid-19 recovery stimulus funding to fossil fuel production rather than to alternative energy. The UN secretary general António Guterres declared that "Humanity is waging war on nature. This is suicidal. Nature always strikes back – and it is already doing so with growing force and fury." Guterres also said there is still cause for hope, with US president elect Joe Biden having suggested that the US will join other large emitters like China and the E.U. in adopting targets to reach net zero emissions.[38][39] [40]

Illness and deaths
Hypothetical number of global deaths which would have resulted from energy production if the world's energy production was met through a single source, in 2014.

Environmental pollution from fossil fuels impacts humans because particulates and other air pollution from fossil fuel combustion cause illness and death when inhaled. These health effects include premature death, acute respiratory illness, aggravated asthma, chronic bronchitis and decreased lung function. The poor, undernourished, very young and very old, and people with preexisting respiratory disease and other ill health, are more at risk.[41] Total global air pollution deaths reach 7 million annually.[42]

While all energy sources have inherently adverse effects, the data shows that fossil fuels cause the highest levels of greenhouse gas emissions and are the most dangerous for human health. In contrast, modern renewable energy sources appear to be safer for human health and cleaner. The death rate from accidents and air pollution in the EU are as follows per terawatt-hour: coal (24.6 deaths), oil (18.4 deaths), natural gas (2.8 deaths), biomass (4.6 deaths), hydropower (0.02 deaths), nuclear energy (0.07 deaths), wind (0.04 deaths), and solar (0.02 deaths). The greenhouse gas emissions from each energy source are as followed measured in tonnes: coal (820 tonnes), oil (720 tonnes), natural gas (490 tonnes), biomass (78-230 tonnes), hydropower (34 tonnes), nuclear energy (3 tonnes), wind (4 tonnes), and solar (5 tonnes).[43] As the data shows, coal, oil, natural gas, and biomass cause higher death rates and higher levels of greenhouse gas emissions than hydropower, nuclear energy, wind, and solar power. Scientists propose that 1.8 million lives have been saved by replacing fossil fuel sources with nuclear power.[44]

Phase-out
This paragraph is an excerpt from Fossil fuel phase-out[edit]

Fossil fuel phase-out is the gradual reduction of the use of fossil fuels to zero.

It is part of the ongoing renewable energy transition. Current efforts in fossil fuel phase-out involve replacing fossil fuels with sustainable energy sources in sectors such as transport, and heating. Alternatives to fossil fuels include electrification, hydrogen and aviation biofuel.
Investment: Companies, governments and households invested $501.3 billion in decarbonization in 2020, including renewable energy (solar, wind), electric vehicles and associated charging infrastructure, energy storage, energy-efficient heating systems, carbon capture and storage, and hydrogen.[45]
Cost: With increasingly widespread implementation of renewable energy sources, costs have declined, most notably for energy generated by solar panels.[46]
Levelized cost of energy (LCOE) is a measure of the average net present cost of electricity generation for a generating plant over its lifetime.

Industry
Main articles: Coal industry and Petroleum industry
Further information: Fossil fuel exporters and Fossil fuels lobby

In 2014, the global energy industry revenue was about US$8 trillion,[47] with about 84% fossil fuel, 4% nuclear, and 12% renewable (including hydroelectric).[48]

In 2014, there were 1,469 oil and gas firms listed on stock exchanges around the world, with a combined market capitalization of US$4.65 trillion.[49] In 2019, Saudi Aramco was listed and it touched a US$2 trillion valuation on its second day of trading,[50] after the world's largest initial public offering.[51]

Economic effects

Air pollution from fossil fuels in 2018 has been estimated to cost US$2.9 trillion, or 3.3% of global GDP.[10]

Subsidy

The International Energy Agency estimated 2017 global government fossil fuel subsidies to have been $300 billion.[52]

A 2015 report studied 20 fossil fuel companies and found that, while highly profitable, the hidden economic cost to society was also large.[53][54] The report spans the period 2008–2012 and notes that: "For all companies and all years, the economic cost to society of their CO
2 emissions was greater than their after‐tax profit, with the single exception of ExxonMobil in 2008."[53]:4 Pure coal companies fare even worse: "the economic cost to society exceeds total revenue in all years, with this cost varying between nearly $2 and nearly $9 per $1 of revenue."[53]:5 In this case, total revenue includes "employment, taxes, supply purchases, and indirect employment."[53]:4

Fossil fuel prices generally are below their actual costs, or their "efficient prices," when economic externalities, such as the costs of air pollution and global climate destruction, are taken into account. Fossil fuels are subsidized in the amount of $4.7 trillion in 2015, which is equivalent to 6.3% of the 2015 global GDP and are estimated to grow to $5.2 trillion in 2017, which is equivalent to 6.5% of global GDP. The largest five subsidizers in 2015 were the following: China with $1.4 trillion in fossil fuel subsidies, United States with $649 billion, Russia with $551 billion, the European Union with $289 billion, and India with $209 billion. Had there been no subsidies for fossil fuels, global carbon emissions would have been lowered by an estimated 28% in 2015, air-pollution related deaths reduced by 46%, and government revenue increased by $2.8 trillion or 3.8% of GDP.[55]

See also

Footnotes
  1. "thermochemistry of fossil fuel formation" (PDF).
  2. Schmidt-Rohr, K. (2015). "Why Combustions Are Always Exothermic, Yielding About 418 kJ per Mole of O2", J. Chem. Educ. 92: 2094-2099. http://dx.doi.org/10.1021/acs.jchemed.5b00333
  3. Paul Mann, Lisa Gahagan, and Mark B. Gordon, "Tectonic setting of the world's giant oil and gas fields", in Michel T. Halbouty (ed.) Giant Oil and Gas Fields of the Decade, 1990–1999, Tulsa, Okla.: American Association of Petroleum Geologists, p. 50, accessed 22 June 2009.
  4. "Fossil fuel". ScienceDaily. Archived from the original on 10 May 2012.
  5. "Primary energy: consumption by fuel". BP Statistical Review of World Energy 2019. BP. 2019. p. 9. Retrieved 7 January 2020.
  6. World Bank, International Energy Agency, Energy Sector Management Assistance Program. "Renewable energy consumption (% of total final energy consumption) | Data". data.worldbank.org. World Bank. Retrieved 12 February 2019.CS1 maint: uses authors parameter (link)
  7. "2018 at a glance" (PDF). BP Statistical Review of World Energy 2019. BP. 2019. p. 2. Retrieved 7 January 2020.
  8. Miller, G.; Spoolman, Scott (2007). Environmental Science: Problems, Connections and Solutions. Cengage Learning. ISBN 978-0-495-38337-6. Retrieved 14 April 2018 – via Google Books.
  9. Ahuja, Satinder (2015). Food, Energy, and Water: The Chemistry Connection. Elsevier. ISBN 978-0-12-800374-9. Retrieved 14 April 2018 – via Google Books.
  10. "Quantifying the Economic Costs of Air Pollution from Fossil Fuels" (PDF). Archived from the original (PDF) on 6 April 2020.
  11. Zhang, Sharon. "Air Pollution Is Killing More People Than Smoking—and Fossil Fuels Are Largely to Blame". Pacific Standard. Retrieved 5 February 2020.
  12. Ambrose, Jillian (12 April 2020). "Carbon emissions from fossil fuels could fall by 2.5bn tonnes in 2020". The Guardian. ISSN 0261-3077. Retrieved 27 April 2020.
  13. "What Are Greenhouse Gases?". US Department of Energy. Retrieved 9 September 2007.
  14. Oil fields map Archived 6 August 2012 at the Wayback Machine. quakeinfo.ucsd.edu
  15. Hsu, Chang Samuel; Robinson, Paul R. (2017). Springer Handbook of Petroleum Technology (2nd, illustrated ed.). Springer. p. 360. ISBN 978-3-319-49347-3. Extract of p. 360
  16. Caspar Neumann; William Lewis (1759). The Chemical Works of Caspar Neumann ... (1773 printing). J. and F. Rivington. pp. 492–.
  17. "fossil". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.) - "fossil [...] adj. [...] Obtained by digging; found buried in the earth. Now chiefly of fuels and other materials occurring naturally in underground deposits; esp. in FOSSIL FUEL n."
  18. "fossil". Oxford English Dictionary (Online ed.). Oxford University Press. (Subscription or participating institution membership required.) - "fossil [...] n. [...] Something preserved in the ground, esp. in petrified form in rock, and recognizable as the remains of a living organism of a former geological period, or as preserving an impression or trace of such an organism."
  19. "Encyclopædia Britannica, use of oil seeps in ancient times". Retrieved 9 September 2007.
  20. Bilkadi, Zayn (1992). "Bulls From the Sea: Ancient Oil Industries". Aramco World. Archived from the original on 13 November 2007.
  21. Ball, Max W.; Douglas Ball; Daniel S. Turner (1965). This Fascinating Oil Business. Indianapolis: Bobbs-Merrill. ISBN 978-0-672-50829-5.
  22. Kaldany, Rashad, Director Oil, Gas, Mining and Chemicals Dept, World Bank (13 December 2006). Global Gas Flaring Reduction: A Time for Action! (PDF). Global Forum on Flaring & Gas Utilization. Paris. Retrieved 9 September 2007.
  23. "Oil Sands Global Market Potential 2007". Retrieved 9 September 2007.
  24. Editor, Damian Carrington Environment (12 December 2017). "Insurance giant Axa dumps investments in tar sands pipelines". The Guardian. Retrieved 24 December 2017.CS1 maint: extra text: authors list (link)
  25. Oswald Spengler (1932). Man and Technics (PDF). Alfred A. Knopf. ISBN 0-8371-8875-X.
  26. Griffin, Rodman (10 July 1992). "Alternative Energy". 2 (2): 573–596. Cite journal requires |journal= (help)
  27. Michael Stephenson (2018). Energy and Climate Change: An Introduction to Geological Controls, Interventions and Mitigations. Elsevier. ISBN 978-0128120217.
  28. Neukom et al. 2019.
  29. "Global Annual Mean Surface Air Temperature Change". NASA. Retrieved 23 February 2020.
  30. "The European Power Sector in 2020 / Up-to-Date Analysis on the Electricity Transition" (PDF). ember-climate.org. Ember and Agora Energiewende. 25 January 2021. Archived (PDF) from the original on 25 January 2021.
  31. EPA (19 January 2017). "Climate Impacts on Ecosystems". Retrieved 7 December 2020.
  32. "WHO calls for urgent action to protect health from climate change". World Health Organization. November 2015. Retrieved 7 December 2020.
  33. World Meteorological Organization (2020). WMO Statement on the State of the Global Climate in 2019. WMO-No. 1248. Geneva. ISBN 978-92-63-11248-4.
  34. US EPA. "Overview of Greenhouse Gases". Retrieved 7 December 2020.
  35. Coal Combustion: Nuclear Resource or Danger Archived 5 February 2007 at the Wayback Machine – Alex Gabbard
  36. Nuclear proliferation through coal burning Archived 27 March 2009 at the Wayback Machine – Gordon J. Aubrecht, II, Ohio State University
  37. American Coal Ash Association. "CCP Production and Use Survey" (PDF).
  38. Damian Carrington (2 December 2020). "World is 'doubling down' on fossil fuels despite climate crisis – UN report". The Guardian. Retrieved 7 December 2020.
  39. Fiona Harvey (2 December 2020). "Humanity is waging war on nature, says UN secretary general". The Guardian. Retrieved 7 December 2020.
  40. "The Production Gap: The discrepancy between countries' planned fossil fuel production and global production levels consistent with limiting warming to 1.5°C or 2°C" (PDF). UNEP. December 2020. Retrieved 7 December 2020.
  41. Liodakis, E; Dashdorj, Dugersuren; Mitchell, Gary E. (2011). "The nuclear alternative". Energy Production within Ulaanbaatar, Mongolia. AIP Conference Proceedings. 1342 (1): 91. Bibcode:2011AIPC.1342...91L. doi:10.1063/1.3583174.
  42. Watts N, Amann M, Arnell N, Ayeb-Karlsson S, Belesova K, Boykoff M; et al. (2019). "The 2019 report of The Lancet Countdown on health and climate change: ensuring that the health of a child born today is not defined by a changing climate". Lancet. 394 (10211): 1836–1878. doi:10.1016/S0140-6736(19)32596-6. PMID 31733928.CS1 maint: multiple names: authors list (link)
  43. "What are the safest and cleanest sources of energy?". Our World in Data. Retrieved 29 December 2020.
  44. Jogalekar, Ashutosh. "Nuclear power may have saved 1.8 million lives otherwise lost to fossil fuels, may save up to 7 million more". Scientific American Blog Network. Retrieved 29 December 2020.
  45. "Energy Transition Investment Hit $500 Billion in 2020 – For First Time". BloombergNEF. (Bloomberg New Energy Finance). 19 January 2021. Archived from the original on 19 January 2021.
  46. Chrobak, Ula (author); Chodosh, Sara (infographic) (28 January 2021). "Solar power got cheap. So why aren't we using it more?". Popular Science. Archived from the original on 29 January 2021. ● Chodosh's graphic is derived from data in "Lazard's Levelized Cost of Energy Version 14.0" (PDF). Lazard.com. Lazard. 19 October 2020. Archived (PDF) from the original on 28 January 2021.
  47. Seba, Tony (27 June 2014). Clean Disruption of Energy and Transportation: How Silicon Valley Will Make Oil, Nuclear, Natural Gas, Coal, Electric Utilities and Conventional Cars Obsolete by 2030. Tony Seba. p. 3. ISBN 978-0-692-21053-6.
  48. "International Energy Outlook 2019". U.S. Energy Information Administration. Retrieved 11 January 2020.
  49. Evans, Simon (27 August 2014). "Why fossil fuel divestment won't be easy". Carbon Brief. Retrieved 10 January 2020. There are 1,469 oil and gas firms listed on stock exchanges around the world, worth a combined $4.65 trillion.
  50. Kerr, Simeon; Massoudi, Arash; Raval, Anjli (19 December 2019). "Saudi Aramco touches $2tn valuation on second day of trading". Financial Times. Retrieved 10 January 2020.
  51. Raval, Anjli; Kerr, Simeon; Stafford, Philip (5 December 2019). "Saudi Aramco raises $25.6bn in world's biggest IPO". Financial Times. Retrieved 10 January 2020.
  52. "Fossil-fuel subsidies". International Energy Agency. Archived from the original on 4 February 2019. Retrieved 7 February 2019.
  53. Hope, Chris; Gilding, Paul; Alvarez, Jimena (2015). Quantifying the implicit climate subsidy received by leading fossil fuel companies — Working Paper No. 02/2015 (PDF). Cambridge: Cambridge Judge Business School, University of Cambridge. Archived from the original (PDF) on 28 March 2016. Retrieved 27 June 2016.
  54. "Measuring fossil fuel 'hidden' costs". University of Cambridge Judge Business School. 23 July 2015. Retrieved 27 June 2016.
  55. International Monetary Fund (IMF), May 2019, "IMF Working Paper, Global Fossil Fuel Subsidies Remain Large: An Update Based on Country-Level Estimates", Abstract and p. 24, WP/19/89

Further reading
  • Ross Barrett and Daniel Worden (eds.), Oil Culture. Minneapolis, MN: University of Minnesota Press, 2014.
  • Bob Johnson, Carbon Nation: Fossil Fuels in the Making of American Culture. Lawrence, KS: University Press of Kansas, 2014.
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