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Hubbert peak

The Hubbert peak theory, also known as peak oil, is an influential theory concerning the long-term rate of conventional oil production and depletion. Geophysicist M. King Hubbert created the theory as a mathematical model for use in predicting the rate of future oil production and subsequent depletion for an oilfield, as well as the combined production of multiple oil fields of entire regions or nations. Before Hubbert's model, no one had created a model that accurately predicted the rate of future oil production applicable beyond a single oil well.

Given past oil production data, the model predicts the date of maximum oil production output for an oilfield, multiple oil fields, or an entire region. This maximum output point is referred to as the peak. The period after the peak is referred to as depletion. The graph of the rate of oil production for an individual oil field over time follows a bell-shaped curve: first, a slow steady increase of production; then, a sharp increase; then, a plateau (the "peak"); then, a slow decline; and, finally, a steep decline. In 1956, Hubbert accurately predicted the peak of oil production would take place in the early 1970s for the continental United States. In 1971, he predicted, using high and low estimates of global oil reserve data available to him at the time, that global oil production would peak between 1995 and 2000. This peak has not occurred, and the implications for the model are controversial. Some petroleum economists, such as Michael Lynch , argue that the Hubbert model is unapplicable globally. Others, such as Colin Campbell, argue that the Hubbert model is fundamentally correct, and that the world faces the start of oil depletion between 2004 and 2015 -- potentially leading to a major global crisis in the early 21st century.

One piece of data in this argument is the World Petroleum Assessment issued by the United States Geological Survey . It estimates, based on current recovery rates, that there are enough petroleum reserves to continue current production rates for at least 50 to 100 years. Reactions to this estimate vary, with Campbell arguing that the USGS estimates are methodologically flawed and that there will be a peak in global oil production anywhere between 2004 and 2015. (Natural gas is expected to peak anywhere from 2010 to 2020.) By contrast, Lynch argues that the USGS estimates are too pessimistic, citing the fact that previous estimates by the USGS have consistently underestimated oil reserves available. As would be expected by any theory that predicts future fuel shortages, the Hubbert model has significant political and economic foreign policy ramifications.

The Hubbert peak theory is most often applied to oil but is applicable to other fossil fuels such as natural gas, coal and non-conventional oil. These and other potential energy alternatives are discussed in future energy development.

The Hubbert curve, devised by M. King Hubbert, predicts future oil availability.
The Hubbert curve, devised by M. King Hubbert, predicts future oil availability.

The theory

In 1956, Hubbert created a mathematical model of petroleum extraction which predicted that the total amount of oil extracted over time would follow a logistic curve. The predicted rate of oil extraction at any given time would then be given by the rate of change of the logistic curve, which follows a bell-shaped curve now known as the Hubbert curve.

The general trend of oil availability, both for a single oil field or entire region, barring extraneous factors such as lack of demand, follows the Hubbert curve. When an oil reserve is discovered, production is initially small, because all the required infrastructure has not been installed. Step by step, more wells are drilled and better facilities are installed in order to produce an increasing amount of oil. At some point, a peak output is reached that can not be exceeded, even with improved technology or additional drilling. After the peak, oil production slowly but increasingly tapers off. After the peak, but before an oil field is empty, another significant point is reached when it takes more energy to recover, transport and process one barrel of oil than the amount of energy contained in that one barrel of oil. At that point, oil is not worthwhile to extract, and that oil field is abandoned. Hubbert peak theory proponents claim that this is true regardless of the price of oil.

When people use the phrase "the end of cheap oil," they are referring to two things: price increases due to scarcity, and the increasing inefficiency of oil production (cheap from both a monetary and energy efficiency perspective). When oil production first began in the early twentieth century, at the largest oil fields 50 barrels of oil was recovered for every barrel of oil used in the extraction, transportion and refining processes. This ratio becomes increasingly inefficient over time: currently, anywhere between one and five barrels of oil are recovered for every barrel used in the various recovery processes. When this ratio reaches the point where it takes one barrel to recover one barrel, then oil becomes useless as energy. At that point, all energy used to extract oil would result in a net energy loss; society would be more efficient and better off using that remaining energy elsewhere.

The law of conservation of energy states that energy can not be created, only converted. Despite appearances, even oil adheres to this law of nature. Oil is just a quirk of geological history, created when a finite amount of decayed organic matter was compressed underground millions of years ago. Except for geothermal power, tidal power, and nuclear power, all available energy flows and energy reserves (including oil) on earth are or were ultimately provided by the sun.


Hubbert, in 1956, accurately predicted oil production in the continental United States would peak in the early 1970s. U.S. oil production did indeed peak in 1970, and has been decreasing since then. According to Hubbert's model, U.S. oil reserves will be exhausted before the end of the 21st century. Huge, easily exploitable oil fields are likely to be a thing of the past. The Hubbert peak theory, while controversial, is increasingly influencing policy makers both within the oil industry and government.

However, significant criticisms exist. Proponents of peak oil theory point to the fact an increasing percentage of oil fields are either beginning depletion or are already depleted. Critics argue that technology advances and higher prices will allow for the recovery of conventional resources previously thought unrecoverable, and will allow for the exploration of new oil fields.

Exacerbating the potential oil depletion problem is the increasing global demand for oil due to population growth and increased global economic prosperity. In a recent year, 25 billion barrels of oil were consumed worldwide, while only eight billion barrels of new oil reserves were discovered. In 2004, world consumption of crude oil is expected to surpass 82 million barrels per day, which correlates to 30 billion barrels per year. This puts consumption equal to production, leaving no surplus capacity. Even if there are temporarily sufficient oil reserves that could be used to meet rising global demand, there is an unknown limit on the increase of oil production capacity, absent additional investment in oil production, transportation and refining facilities.

Implications of a world peak

The implications of a world peak, or lack thereof, are large. Economic growth and prosperity over the twentieth century have, in large part, been due to the use of oil as a fuel and fertilizer. The belief that there will be a world peak in oil production followed by a sharp decline implies that much of the lifestyle and prosperity of the twentieth century is unsustainable, and that limitations of resources will force a drastic change in the way that people live. By contrast, the belief that the Hubbert model is fundamentally incorrect -- that humanity is no where near the fundamental limits of oil production -- implies that the prosperity and lifestyle that has occurred in the twentieth century is sustainable, and that no drastic limits on resource consumption are required.

This argument also impacts development in the third world, as it touches on the question of whether it is possible for the vast majority of humanity to live at standards of living currently found in the United States and Europe. Pessimists argue that resource limitations make this scenario impossible, while optimists strongly disagree.


Some believe that the decreasing oil production portends a drastic impact on human culture and modern technological society, which is currently heavily dependent on oil as a fuel and chemical feedstock. Over 90% of transportation in the United States relies on oil. Some envisage a Malthusian catastrophe occurring as oil becomes increasingly inefficient to produce. No other known energy source is as cheap to extract, as easy to transport, and as full of energy as oil.

Market solution

A market solution is the belief that the rise of oil prices due to scarcity would stimulate investment in oil replacement technologies and/or more efficient oil extraction technologies. A challenge extant with both non-conventional oil extraction, as well as energy production based on methods other than fossil fuels, is that these sources rely upon fossil fuels for their construction. Were conventional oil and natural gas to become more expensive because of scarcity, alternative energy production costs would grow more expensive in kind.

Presumably, as rising energy costs exceed the labor costs of construction, and as long-term interest rates drop to match the falling productivity of an energy-starved economy, other sources of energy would become increasingly more attractive. However, critics argue that market solution proponents mistakingly phrase everything in terms of money, e.g., they only consider the price of oil when in reality, the important metric is energy efficiency (the ratio of extracted energy over energy used by the extraction and refining processes).

Additionally, some critics believe that a market solution is likely to result in profiteering by energy suppliers from the price shock, due to the scarcity of oil and artificial scarcity of replacement sources of energy, rather than providing a smooth transition from oil to other fuels.

Increased fuel efficiency

Any moderate oil price increase is expected to stimulate an increase in transportation fuel efficiency. This would postpone and lessen the impact of severe oil shortages. In addition, some governments currently mandate a minimum fuel efficiency standard for automobiles.

Political implications

As of 2004, the United States economy is the world's largest user of oil, with a historical reliance on what have been, and still are, some of the world's lowest oil prices. Its position as the global hyperpower rests on its economic supremacy, which in turn depends heavily on oil. At the same time, the world's largest oil reserves are held by Saudi Arabia, followed by those of Iraq, the United Arab Emirates, Iran and Russia. If a Hubbert Peak were to occur, and oil were to become a progressively more scarce commodity, it would be reasonable to expect massive political and economic tension between its principal consumers and producers.

Some observers see the 2003 U.S. invasion of Iraq as the beginning of a geopolitical struggle driven by anticipated oil scarcity, whereby the U.S. will seek to establish a long-term military presence in the Middle East in order to be able to maintain oil supplies, by force if necessary. Others view this as a conspiracy theory with no basis in fact.

Lifestyle choices

A significant percentage of today's resource use is based upon lifestyle choice rather than unalterable human needs. The United States accounts for 5% of world population but consumes 25% of the world's fossil fuel based energy. The voluntary simplicity movement advocates a shift from consumerism to a reduced use of natural resources and energy. Irregardless of choice, a period of decreasing fossil fuel reserves is likely to lead to a decrease of demand for goods and services. However, environmentally friendly, low-energy replacements for many current activities are increasingly or already available. For example, commuting using bicycles and mass transit as well as eating home-cooked locally grown organic meals instead of highly-packaged convenience foods from restaurants and grocery stores. Jobs that make use of telecommuting or that are nearer to home with shorter commuting distance may become increasingly desirable.

Some critics of consumerism argue that our current economy has addictive elements, exacerbated by advertising and overuse of credit; this addiction has been dubbed affluenza. If so, any future decline in energy supplies may force people to break out of their current consumer lifestyle and begin to reevaluate their values. Such a re-evaluation may induce a tipping point to further accelerate people away from a high-energy lifestyle. Other processional effects may include healthier lifestyles (reducing demands for medical resources) and improved communities and family relationships (reducing demands for government resources for social problems).

Changes in lifestyle choices have other important practical advantages. First, under extreme conditions, social change can proceed much more rapidly than large-scale infrastructure change. Second, the other alternatives assume the results are technologically feasible, whereas decreased energy availability can be planned for a potentially mitigated by increased efficiency and less demand. Finally, living simply can reduce one's reliance on the well-being of the global economy. Even so, a serious shift from a high-energy lifestyle could lead to increased unemployment and bankrupt many businesses and markets.

Others are pessimistic of the lifestyle changes needed to reduce energy demand. If society doesn't proactively reduce energy use and consumption remains high as supplies run entirely out, this reduction may be imposed by a reducing energy supply. Many of these lifestyle changes are seen as unpleasant. Airplanes and cars may be replaced by railroads, ships and mass transport. People may travel much less, for example staying at home during holidays. Foods like meat, chocolate, coffee, tea, fish, and milk may be be replaced by locally produced cereals and vegetables. Air conditioning may disappear. People may move to smaller houses that cost less to build and heat. In general, there will be less consumption because higher power cost affects all stages of production and transportation. In extreme cases there will be rationing of electricity and heating.

Alternatives to oil

If or when conventional oil begins depletion the following alternative energy options may be increasingly relied upon to meet the world's energy needs.

Non-conventional oil

Main article: Non-conventional oil

Non-conventional oil is another source of oil separate from conventional or traditional oil. Non-conventional sources include: tar sands, oil shale and bitumen. Potentially significant deposits of non-conventional oil include the Athabasca Tar Sands site in northwestern Canada and the Venezuelan Orinoco tar sands. Oil companies estimate that the Athabasca and Orinoco sites (both of similar size) have as much as two-thirds of total global oil deposits, but they are not yet considered proven reserves of oil. Extracting a significant percentage of world oil production from tar sands may not be feasible. The extraction process takes a great deal of energy for heat and electrical power, presently coming from natural gas (itself in short supply). There are proposals to build a series of nuclear reactors to supply this energy. Non-conventional oil production is currently less efficient, and has a larger environmental impact than conventional oil production.

Other fossil fuels and the Fischer-Tropsch process

It is expected by geologists that natural gas will peak 5-15 years after oil does. There are large but finite coal reserves which may increasingly be used as a fuel source during oil depletion. The Fischer-Tropsch process converts carbon dioxide, carbon monoxide and methane into liquid hydrocarbons of various forms. The carbon dioxide and carbon monoxide is generated by partial oxidation of coal and wood-based fuels. This process was developed and used extensively in World War II by the Germans, who had limited access to crude oil supplies. It is today used in South Africa to produce most of country's diesel from coal. Since there are large but finite coal reseves in the world, this technology could be used as an interim transportation fuel if conventional oil were to disappear. There are several companies developing the process to enable practical exploitation of so-called stranded gas reserves, those reserves which are impractical to exploit with conventional gas pipelines and LNG technology.

Methanol can be used in internal combustion engines with minor modifications. It usually is made from natural gas, sometimes from coal and could be made from any carbon source including CO2.

Nuclear power

The U.S. would require at least an elevenfold increase in nuclear power production to replace both the current amount of electricity generated from fossil fuels and gasoline usage. This likely would involve using hydrogen as an energy carrier (see below), which adds inefficiency (perhaps increasing this ratio). There may be a limited supply of uranium and other minerals, such as thorium, for use as fuel for nuclear power.

Fast breeder reactors are another possibility. As opposed to current LWR (light water reactors) which burn the rare isotope of uranium U-235, fast breeder reactors produce plutonium from U-238, and then fission that to produce electricity and thermal heat. It has been estimated that there is anywhere from 10,000 to five billion years' worth of U-238 for use in these power plants, and that they can return a high ratio of energy returned on energy invested (EROEI), and avoid some of the problems of current reactors by being automated, passively safe, and reaching economies of scale via mass production. There are a few such research projects working on fast breeders - Lawrence Livermore National Laboratory being one, currently working on the small, sealed, transportable, autonomous reactor (SSTAR ).

The long-term radioactive waste storage problems of nuclear power have not been solved, although onsite spent fuel storage in casks has allowed power plants to make room in their spent fuel pools. One possible solution several countries are considering is using underground repositories. The U.S nuclear waste from various locations is planned to be entombed inside Yucca Mountain, Nevada.

Renewable energy

Main article: Renewable energy

Another possible solution to an energy shortage or predicted future shortage would be to use some of the world's remaining fossil fuel reserves as an investment in renewable energy infrastructure such as wind power, solar power, tidal power, geothermal power, hydropower, thermal depolymerization and biodiesel which do not suffer from a finite energy reserves, but do have a finite energy flow. The construction of sufficiently large renewable energy infrastructure might avoid the economic consequences of an extended period of decline in fossil fuel energy supply per capita.

Biodiesel has some potential advantages because it could replace petroleum diesel without engine modification, and could reuse existing fuel distribution infrastructure. Hyrdro electric power currently produces electricity more cheaply than natural-gas turbines, as a result, nearly every river in North America that can be dammed has been. Gigantic hydropower projects have recently been built all around the world (see Itaipu and Three Gorges Dam). Another promising renewable energy source may be wind power (currently over four times as efficient as solar PV power systems). Solar trough concentrating power systems are economic in arid and semiarid regions today. This is particularly true if these solar power plants are designed to take full advantage of the combined heat and power potential outputs. These solar facilities can produce not only electricity, but also steam, hot water, chilled water, and ice using absorption refrigeration cycle equipment. Thermal depolymerization, like biodiesel, has significant current interest and investment because of the potential to replace or gradually replace oil based transportation fuels.

One factor potentially in renewable energy's favor is its much smaller environmental impact. Renewable energy sources may have a significantly smaller total "cost" compared with fossil fuel production after factoring in pollution, in other words, oil production is likely more expensive than the initial price seems to indicate and relative to renewable energy if you factor in the "cost" of pollution.


Methane clathrate, solar power satellite, abiogenic petroleum origin, and helium on the moon have been proposed as very speculative solutions to an energy peak. They are, for various reasons, probably not feasible today. This could change with new technology, for example a working space elevator which would dramatically reduce costs for space technologies.

More long-term, proposed future technologies, such as hydrocarbons on other planets and Dyson spheres, indicate that humanity is not now reaching some unavoidable theoretical limit to energy supply.


Main Article: Hydrogen economy

Some proponents claim hydrogen will be the next major thing in the field of energy, however, most people in the sustainable energy development community see any focus on hydrogen as an inefficient use of resources. According to the majority of energy experts and researchers, hydrogen is currently impractical as an alternative to fossil based liquid fuels. There are no uncombined hydrogen reserves in nature. Hydrogen is not a source of chemical energy rather it is an energy carrier like electricity, which must be produced using another energy source. Using the steam-reformed methane chemical conversion process to generate hydrogen requires natural gas, itself potentially in increasingly short supply. Another method of Hydrogen production is water electrolysis which can use electricity generated from any combination of: fossil fuels, nuclear, and/or renewable energy sources. Genetically modified organisms have also been proposed as a way to produce hydrogen.

The idea of using Hydrogen as a transportation fuel is currently impractical. Hydrogen is inefficient to produce, insufficiently energy dense (hydrogen gas tanks would need to be 2-3 times as large), and inexpensive to transport and convert back to electricity. However, theoretically it is more efficient to burn fossil fuels to produce hydrogen than burning oil directly in car engines (efficiency of scale). However, that analysis does not take into consideration the significant energy cost of having to build hundreds of millions of new hydrogen powered vehicles plus hydrogen fuel distribution infrastructure. Research is underway on the feasibility of Hydrogen as a fuel, the outcome is at best uncertain.


See also

Further reading

  • M. King Hubbert, "Energy from Fossil Fuels", Science, vol. 109, pp. 103-109, February 4, 1949
  • Kenneth S. Deffeyes, Hubbert's Peak: The Impending World Oil Shortage , Princeton University Press, 2003, ISBN 0691116253
  • Colin J. Campbell, The Coming Oil Crisis , Multi-Science Publishing Co. Ltd., 2004, ISBN 0906522110
  • Richard Heinberg, The Party's Over: Oil, War and the Fate of Industrial Societies , New Society Publishers, 2003, ISBN 0865714827
  • David Goodstein, Out of Gas: The End of the Age of Oil , W.W. Norton & Company, 2004, ISBN 0393058573
  • Stephen Leeb and Donna Leeb, The Oil Factor: How Oil Controls the Economy and Your Financial Future , Warner Books, 2004, ISBN 0446533173
  • Jeremy Rifkin, The Hydrogen Economy: After Oil, Clean Energy From a Fuel-Cell-Driven Global Hydrogen Web , Blackwell Publishers, 2002, ISBN 0745630421
  • Paul Roberts, The End of Oil: On the Edge of a Perilous New World , Houghton Mifflin, 2004, ISBN 0618239774
  • Paul Roberts, Last Stop Gas, Harper's Magazine, August 2004, pp. 71-72
  • Documentary film The End of Suburbia

External links

  • Energy Bulletin - Peak oil related news stories
  • Peak oil forum
  • Dwindling Supply vs. Abundant Oil: A Timely Debate - General Session of the Society of Petroleum Engineers 2004

Hubbert theory advocacy and research

  • Peak Oil presentation by Dr. Campbell, TU Clausthal
  • M. King Hubbert Center for Petroleum Supply Studies
  • ASPO, Association for the Study of Peak Oil & Gas
  • ODAC, Oil Depletion Analysis Centre independent, UK education charity
  • - Raising awareness of Britain's Energy Future
  • Peak Oil News and Message Boards
  • Yahoo Group: Running on Empty
  • PeakOilAction people working together to raise awareness of oil depletion, prepare for post petroleum age
  • International Peak Oil Awareness Meetup meet others in your area on 2nd Wednesday of month
  • Oilcrash
  • UK Survival in the 21st Century
  • Hubbert Peak of Oil Production biography , tribute , graph showing oil production in lower 48 US states following Hubbert's predictions , The Coming Global Energy Crisis
  • Energy Crisis/Shortage , English, German
  • Culture Change , promotes lifestyle change as a reponse to the Hubbert peak
  • Ecological Basis for Great Change
  • MuseLetter
  • Life After The Oil Crash
  • Wolf at the Door
  • Die Off
  • Planet for Life
  • From the Wilderness
  • M. King Hubbert on the Nature of Growth
  • Will The End of Oil Mean The End of America? Common Dreams NewsCenter article
  • David Goodstein on Peak Oil MSNBC news article
  • The End of Cheap Oil National Geographic article
  • Peak Oil News Blog
  • List of Resources on Peak Oil
  • Review: Oil-based technology and economy - prospects for the future
    The Danish Board of Technology (Teknologi-radet)
  • Crisis Energética Spanish page about Peak Oil.
  • Facts on the inevitable world-wide energy transition .
  • Play SimOil!
  • Post Carbon Institute
  • The End of Suburbia
  • Global Public Media
  • Sign the Oil Peak and Decline Declaration!
  • Before The Wells Run Dry - analysis about the oil situation from, an Irish website

Hubbert theory criticisms

  • The New Pessimism about Petroleum Resources: Debunking the Hubbert Model (and Hubbert Modelers)
  • The end of the age of oil?
  • Known Saudi Arabian Oil Reserves Tripled
  • Peak production in the news again
  • The global energy outlook for the 21sth century
  • International Energy Agency press release
  • Oil shale back in the picture

Last updated: 02-10-2005 14:05:07
Last updated: 02-25-2005 21:04:11