Bentley,R.W.(2002): Global oil & gas depletion: an overview. Energy Policy, 30, 189-205.


 The world's production of conventional hydrocarbons will soon decline. Hydrocarbon shortages are inevitable unless radical changes occur in demand, or in the supply of non-conventional hydrocarbons. The details are as follows:
 Global conventional oil supply is currently at political risk. This is because the sum of conventional oil production from all countries in the world, except the five main Middle-East suppliers, is near the maximum set by physical resource limits. Should Middle-East suppliers decide to substantially curtail supply, the shortfall cannot be replaced by conventional oil from other sources.
 World conventional oil supply will soon be at physical risk. The Middle-East countries have only little spare operational capacity, and this will be increasingly called upon as oil production declines elsewhere. Large investments in Middle-East production, if they occur, could raise output, but only to a limited extent. (A partial exception is Iraq, but even here, there would be significant delays before prospects are confirmed, and infrastructure is in place.) If demand is maintained, and if large investments in Middle-East capacity are not made, the world will face the prospect of oil shortages in the near term.
 Even with large investments, resource limits will force Middle-East production to decline fairly soon, and hence also global conventional oil production. The date of this resource-limited global peak depends on the size of Middle-East reserves, which are poorly known, and unreliably reported. Best estimates put the physical peak of global conventional oil production between 5 and 10 years from now.
 The world contains large quantities of non-conventional oil, and various oil substitutes. But the rapidity of the decline in the production of conventional oil makes it probable that these non-conventional sources cannot come on-stream fast enough to fully compensate. The result will be a sustained global oil shortage.
 For conventional gas, the world's original endowment is probably about the same, in energy terms, as its endowment of conventional oil. Since less gas has been used so far compared to oil, the world will turn increasingly to gas as oil declines. But the global peak in conventional gas production is already in sight, in perhaps 20 years, and hence the global peak of all hydrocarbons (oil plus gas) is likely to be in about 10 or so years.』

 世界の在来型石油供給は現在、政治的 リスクをもつ。これは、中東の5大供給国を除いて、世界のすべての国からの在来型石油生産量の合計が、物理的な資源限界によって定められた最大量に近いためである。中東供給国が実質的に供給を抑えるよう決めると、その不足分は他の供給国からの在来型石油では取って代われない。
 世界の在来型石油供給はまもなく物理的 リスクをもつだろう。中東諸国は操業能力にごくわずかの予備があるだけで、他の場所の石油生産が低下するとともに、ますます求められるだろう。中東での生産に大きな投資がもしあるならば、限られた範囲のみだが、生産高を上げられるだろう。(一部の例外はイラクだが、しかしたとえここでも、有望地が確認され、インフラが整うまえに、かなりの遅れが生じるだろう。) 需要が維持され、かつ中東の能力に大きな投資がなされないならば、世界は近い時期に石油不足の可能性に直面するだろう。
 大きな投資がなされても、資源の限界 は中東の生産そしてそれゆえに世界の在来型石油生産をも、かなりはやく低下させることになるだろう。この資源の限界による世界のピークの時期は、中東の埋蔵量の大きさによっており、それはよく知られておらず、報告もあてにならない。最良の見積りからは、世界の在来型石油生産の物理的ピークは、今から5〜10年の間となる。

Part I: The research covered by this paper
 1. conventional oil
  1.1. The modelling of Campbell and Laherrere(二番目のeの頭に`)
  1.2. Checking by the University of Reading
  1.3. Findings and uncertainties
  1.4. Conventional oil depletion: summary
 2. Conventional gas
  2.1. Estimates of total endowment
  2.2. Conventional gas depletion: summary
 3. Non-conventional oil and gas
  3.1. The resource base
  3.2. Rate of production
Part II. Other views of the future of oil and gas
 4. Misconceptions
  4.1. Confusion between reserves, and the total recoverable oil
  4.2. Confusion between proved reserves, and (proved+probable) reserves: the ‘reserves replacement’ problem
  4.3. Atrocious reporting of proved reserves
  4.4. Danger of using the ‘R/P’ ratio
  4.5. Past forecasts
 5. Experts' views
  5.1. Exploration geologists
  5.2. Oil companies
  5.3. The United States Geological Survey (USGS)
   (i) Reserves
   (ii) Oil yet-to-find
   (iii) Reserves growth
  5.4. The International Energy Agency
  5.5. The US DoE Energy Information Administration
  5.6. Checking the ‘expert's’ views
Part III. Perspective, and Conclusions
 6. Perspective
 7. Conclusions
Appendix A. Predicting conventional oil peak
Appendix B
 Definitions and units

Fig. 1. Possible future production of ‘All Hydrocarbons’. Note that gas is represented here at a conversion factor of 10 Tcf gas=1Gb oil equivalent. This is an industry norm, but the calorific value is nearer 6 Tcf gas=1Gb oil equivalent. On the latter basis, the area of the graph representing gas becomes proportionally larger, but the overall shape of the graph changes little; and the peak date, of about 2010 for ‘All Hydrocarbons’ production, is essentially unchanged. Source:Colin Campbell; presentation at the Petrotech 2001 Conference, New Delhi, India, January 2001.
図1.「すべての炭化水素」の可能性のある将来の生産量.天然ガスはここでは10Tcf(テラ・キュービック・フィート)天然ガス=1Gb(ギガ・バレル)石油換算という変換係数で表わされていることに注意。これは産業標準であるが、発熱量では6Tcf天然ガス=1Gb石油換算に近い。後者に基づけば、天然ガスを示す図の領域は比例して大きくなるが、図の全体的な形はほとんど変わらない;そして「すべての炭化水素」についてのおよそ2010年というピーク時期は、本質的に変わらない。出典:コリン・キャンベル;2001年1月にインドのニューデリーでのペトロテク 2001会議での発表。

〔Bentley,R.W.(2002): Global oil & gas depletion: an overview. Energy Policy, 30, 189-205.から〕

Fig. 5. A history of world oil:production, reserves, and yet-to-find in 1950, 1970 and 1998. Notes:excludes NGLs. Data in billion barrels (Gb). Assumes a conventional ultimate of 2000 Gb, and calculates: Yet-to-find=Ultimated−(Cumulative production+Reserves). Reserves here are public domain proved reserves. (This makes the end-’98 yet-to-find somewhat misleading. The industry end-’98 figure for (proved+probable) reserves, excluding NGLs, is around 850 Gb, giving a yet-to-find, based on a 2000Gb ultimate, of about 300 Gb). Depletion curve: Exponential decline once 1000Gb has been produced. Sources: Reserves data from BP Statistical Reviews, and as supplied by EDA Ltd. Production data pre-1965 from Campbell. NGL’s estimated.
図5.世界の石油の歴史:1950年と1970年と1998年における生産量・埋蔵量・未確認量.注:NGLを除く。単位は10億バレル(Gb)。在来型の究極量を2兆バレルと仮定し、未確認量を計算:未確認量=究極量−(累積生産量+埋蔵量)。ここでの埋蔵量は社会共有財産確定埋蔵量。(これは1998年末の未確認(埋蔵)量に多少誤解を招く。産業のNGLを除く(確定+推定)埋蔵量の1998年末値は約8500億バレルで、2兆バレルの究極量を基にすると、未確認量は約3000億バレルとなる)。枯渇曲線:いったん1兆バレルが生産される、指数関数的に減少する。出典:埋蔵量データはBP統計レビューから、またEDA Ltd.から補足。1965年以前の生産量データはキャンベルから。NGLは推定値。

〔Bentley,R.W.(2002): Global oil & gas depletion: an overview. Energy Policy, 30, 189-205.から〕