# Hubbert peak theory

(Redirected from Peak Oil)
A bell-shaped production curve, as suggested by M. King Hubbert in 1956.
2004 U.S. government predictions for oil production other than in OPEC and the former Soviet Union

The Hubbert Peak theory posits that for any given geographical area, from an individual oil field to the planet as a whole, the rate of oil production tends to follow a bell-shaped curve. Early in the curve (pre-peak), production increases due to the addition of infrastructure. Late in the curve (post-peak), production declines due to resource depletion.

"Peak Oil" as a proper noun, also known as Hubbert's peak, refers to a singular event in history: the peak of the entire planet's oil production. After Peak Oil, according to the Hubbert Peak Theory, the rate of oil production on Earth will enter a terminal decline. The theory is named after American geophysicist Marion King Hubbert, who created a model of known oil reserves, and proposed, in a paper he presented to the American Petroleum Institute in 1956 [3], that production of oil from conventional sources would peak in the continental United States between 1965 and 1970, and worldwide within "about half a century" from publication.

When the global peak will occur is a controversial issue. Production peaks are difficult to predict, and generally the only reliable way to identify the timing of any production peak, including the global peak, is in retrospect. United States oil production peaked in 1971 [4]. The peak of world oilfield discoveries occurred in 1962 [5]. Some estimates for the date of worldwide peak in oil production, made by Hubbert and others, have already passed. Estimates for the date of Peak Oil range from 2005 to dates after 2025.

Some industrialized countries are currently highly dependent on oil. Opinions on the effects of Hubbert's peak, and the subsequent terminal decline of global oil production, range from predictions that the market economy will develop alternatives to oil and decrease oil dependence in modern economies, to doomsday scenarios of global economic meltdown and societal collapse.

## Hubbert's theory

The standard Hubbert curve. For applications, the x and y scales are replaced by time and production scales.
A clear example of hubbert theory applying on Norway's production‎

In 1956, Hubbert proposed that crude oil production in a given region over time would follow a bell-shaped curve without giving a precise formula; he later used the Hubbert curve, the derivative of the logistic curve, for estimating future production.

Hubbert assumed that after oil reserves are discovered, oil production at first increases approximately exponentially, as wells are drilled and more efficient facilities are installed. At some point, a peak output is reached, and oil production begins declining until it approximates an exponential decline.

The Hubbert curve satisfies these constraints. Furthermore, it is symmetrical, with the peak of production reached when half of the oil that will ultimately be produced has been. It also has a single peak.

Given past oil production data, a Hubbert curve may be constructed that attempts to approximate past data, and used to provide estimates for future production. In particular, the date of peak oil production and the total amount of oil ultimately produced can be estimated that way.

The standard Hubbert curve is a real-valued function of one real variable; in order to apply it to the real world, scales have to be chosen, one for time and one for oil production, based on the observed data. They are usually given implicitly by specifying the integral of the Hubbert curve, the ultimate total oil production Q, with a unit of billions of barrels, and the initial growth rate asymptotically reached for very early times, a, often expressed in percent per year.

Hubbert also proposed a method for determining the values for Q and a based on empirical data, by considering the ratio of production at a given time and cumulative production to that point as a function not of time but of the cumulative production itself; if production followed a Hubbert curve, this function would have the form $a - \frac{Q}{Q_\infty} a$, a straight line. Thus, by considering the best linear fit to the function actually observed, estimates for a and Q can be obtained.

### Use of multiples curves

, the use of multiple curves instead of one can better model the behavior of diverse systems. In US oil production, Hubbert dealt with a large sampleset that wasn't very politically constrained. How discovery of new resources should be added to a Hubbert curve, and whether they were accounted for in the first place, is always controvertial, but it's intuitively warranted in certain circumstances. Timber production by European powers, for example, would follow its own curves for most of history, followed by the addition of new curves as colonialism took off. [6]

## Peak prediction

In 2004, ASPO predicted that conventional plus unconventional oil production would peak around 2007.
The Energy Information Administration predicts no peak in consumption before at least 2025. Source: International Energy Outlook 2004. The International Energy Agency makes a similar projection

In 1974, Hubbert projected that global oil production would peak in 1995 "if current trends continue" [7] (i.e., 2% growth in consumption per year)[8]. However, in the late 1970s and early 1980s, global oil consumption actually dropped (due to the shift to energy efficient cars, the shift to electricity and natural gas for heating, etc), then rebounded to a lower level of growth in the mid 1980s (see graphics on right). The shift to reduced consumption in these areas meant that the projection assumptions were not realized and, hence, oil production did not peak in 1995.

The Association for the Study of Peak Oil and Gas (ASPO) has calculated that the annual production peak of conventional crude oil was in early 2004. During 2004, approximately 24 billion barrels of conventional oil was produced out of the total of 30 billion barrels of oil; the remaining 6 billion barrels coming from heavy oil and tar sands, deep water oil fields, and natural gas liquids (see adjacent ASPO graph). In 2005, the ASPO revised its prediction for the peak in world oil production, from both conventional and nonconventional sources, to the year 2010[9]. Natural gas is expected to peak anywhere from 2010 to 2020 (Bentley, 2002).

In 2004, 30 billion barrels of oil were consumed worldwide, while only eight billion barrels of new oil reserves were discovered. Huge, easily exploitable oil fields are most likely a thing of the past. In August 2005, the International Energy Agency reported annual global demand at 84.9 million barrels per day (mbd) which means over 31 billion barrels annually. This means consumption is now within 2 mbd of production. At any one time there are about 54 days of stock in the OECD system plus 37 days in emergency stockpiles.

The United States Geological Survey claimed at one time that there are enough petroleum reserves to continue current production rates for 50 to 100 years[10]. That is countered by an important Saudi oil industry insider who says the American government's forecast for future oil supply is a "dangerous over-estimate."[11] Campbell argues that the USGS estimates are methodologically flawed (although he does not claim to be an expert in probability theory)[12]. One problem, for example, is that OPEC countries overestimate their reserves to get higher oil quotas and to avoid internal critique. Population and economic growth will almost certainly lead to increased energy consumption in the future.

According to the Energy Information Administration of the United States Department of Energy, "adjustments to the USGS and MMS estimates are based on non-technical considerations that support domestic supply growth to the levels necessary to meet projected demand levels. [emphasis added]" (Annual Energy Outlook 1998 With Projections to 2020[13]). [This is misquoted; the quoted part is not preceded by "international reserve", and does not make a statement about international reserve estimates.]

Professor Kenneth Deffeyes, author of "Hubbert's Peak" (ISBN 0-691-11625-3) and "Beyond Oil" (ISBN 0-8090-2956-1), asserts that the peak was passed on Dec 16, 2005 [14]. He also asserts that the total of world oil is 2.013 trillion barrels.

World oil supply.[2] Source: IEA
World Oil Supply 2002-2006 Q2. Source: Multiple tables from IEA
World Crude Oil Production 1960-2004. Sources: DOE/EIA, IEA

Chevron states that "oil production is in decline in 33 of the 48 largest oil producing countries". [15] Other countries have also passed their individual oil production peaks.

World oil production growth trends, in the short term, have been decreasing over the last 18 months. Average yearly gains in world oil production from 1987 to 2005 were 1.2MB/day (1.7%). Global production averaged 84.4 MB/day in 2005, up only 0.2 MB/day (0.2%) from 84.2MB/day in Q4 2004 (see figure at right). Production in Q2 2006 was 85.1MB/day, up 0.4MB/day (0.47%) from the same period a year earlier [16]. Yearly gains in the last 8 years ranged from -1.4MB/day (-1.9%; 1998-1999) to 3.3MB/day (4.1%; 2003-2004)[17].

Colin Campbell of the Association for the Study of Peak Oil & Gas (ASPO) has suggested that the global production of conventional oil peaked in the spring of 2004 albeit at a rate of 23-GB/yr, not Hubbert's 13-GB/yr. Another peak oil proponent Kenneth S. Deffeyes predicted in his book Beyond Oil - The View From Hubbert's Peak that global oil production would hit a peak on Thanksgiving Day 2005 (Deffeyes has since revised his claim, and now argues that world oil production peaked on December 16 2005[18]). Texas oilman T. Boone Pickens has stated that worldwide conventional oil production will top out at 85MB/day.[19]

Of the three largest oil fields in the world, two have peaked. Mexico announced that its giant Cantarell Field entered depletion in March, 2006, as did the huge Burgan field in Kuwait in November, 2005. Due to past overproduction, Cantarell is now declining rapidly, at a rate of -13% year over year. [20] In April, 2006, a Saudi Aramco spokesman admitted that its mature fields are now declining at a rate of 8% per year, and its composite decline rate of producing fields is about 2%[21], thus implying that Ghawar, the largest oil field in the world may have peaked.

Chevron has launched the Will You Join Us? [22] campaign, seeking to alert the public to the possibility of petroleum depletion and encourage discussion. The campaign's website notes findings from the International Energy Agency's (IEA) World Energy Outlook 2004: "Fossil fuels currently supply most of the world’s energy, and are expected to continue to do so for the foreseeable future. While supplies are currently abundant, they won’t last forever."

Traditional natural gas supplies are also under the constraints of production peaks, which especially affect specific geographic regions because of the difficulty of transporting the resource over long distances. Natural gas production may have peaked on the North American continent in 2003, with the possible exception of Alaskan gas supplies which cannot be developed until a pipeline is constructed. Natural gas production in the North Sea has also peaked. UK production was at its highest point in 2000, and declining production and increased prices are now a sensitive political issue there. Even if new extraction techniques yield additional sources of natural gas, like coalbed methane, the energy returned on energy invested will be much lower than traditional gas sources, which inevitably leads to higher costs to consumers of natural gas.

## Mitigation

Peak Oil on a license plate of a hybrid car driving past a wind turbine

Mitigation efforts attempt to prevent hazards from developing into disasters altogether, or to reduce the effects of disasters when they occur.

Most oil consumption comes from transportation, 68% in America [23], and there are many forms of transportation that do not require oil or require much less than the standard automobile. Today, these include the application of biofuels, high mpg hybrid vehicles, battery electric vehicles and plug-in hybrid electric vehicles. Solar- or hydrogen- powered demonstration vehicles have also been designed and developed as pilot projects or for engineering school competition. Because America uses 1 in 4 barrels of global oil consumed [24] [25] and uses 68% for transportation, it uses 17% of global oil consumption for transportation and is potentially the largest market for any new type of vehicle.

More comprehensive mitigations include better land use planning through Smart growth to reduce transportation inducements, increased capacity and use of mass transit, vanpooling and carpooling, and human powered transport from current levels [26]. Rationing is also a form of mitigation - see [27] for driving ban schemes and a list of policies and their oil savings in table E-1.

Since mitigation affects the price of oil and the economy it is very important in calculating the timing and shape of a peak. Conversely the shape of the peak[1] affects mitigation efforts. Key questions for mitigation are the viability of solutions such as alternative fuel cars, the roles of government and private sector [28] [29], and how early the switch to these technologies would have to be in order to maintain the lifestyle of a country or even prevent changes to the Earth's carrying capacity.

## Alternative sources for oil

Alternatives are energy sources other than conventional oil and natural gas which can be used instead in one or more applications, such as:

• a prime energy source to generate electricity
• a transportation fuel
• for space heating
• for water heating
• an ingredient in plastics, pesticides, pharmaceuticals, semiconductors, and fertilizers
• a lubricant in industrial machinery and manufacturing.

Popular alternatives include

One near-term alternative source of liquid fuel is the Athabasca Tar Sands in Alberta, Canada. Production from this source is around 1 million bbl/day as of 2006, and is expected to build up to 3.2 million bbl/day by 2015. Higher oil prices have overcome the high costs of extracting heavy oil from this source. The current extraction process, however, requires large inputs of scarce natural gas and fresh water. The figure for recoverable reserves from this source is currently (mid 2006) around 180 billion barrels (cf. the Saudi Arabian reserve of about 260 billion barrels of conventional oil). A similar field, the Orinoco tar sands in Venezuela, is also being exploited. These two are the largest known fields of tar (i.e., bitumen) sands.

## Hubbert peak for Gas

Because gas transport is a complicated operation,the global peak of gas is less important than the peak per continent.The North American peak happened in 2001, according to Western Gas Resources Inc; according to Doug Reynolds, the peak will occur in 2007 [42]; according to Bently, production will peak anywhere from 2010 to 2020 (Bentley, 2002).

## Longterm Hubbert peaks

### Coal

Peak is still very far,but we can observe the example of anthracite in the USA, a hie grade coal, that has peaked in the 1920's.

## References

1. ^ The Shape of World Oil Peaking: Learning From Experience by Robert L. Hirsch [1]
• "Feature on United States oil production." (November, 2002) ASPO Newsletter #23.
• Hubbert, M.K. (1982). Techniques of Prediction as Applied to Production of Oil and Gas, US Department of Commerce, NBS Special Publication 631, May 1982

Global fossil carbon emissions, an indicator of consumption, for 1800-2000. Total is black. Oil is in blue.

Prediction

Economics

Technology

### Books

Michael C. Ruppert, Crossing the Rubicon: The Decline of the American Empire at the End of the Age of Oil