A fresh congressional study paints one of the bleakest pictures yet of how much oil the world can expect over the next 20 years. Global oil production from conventional sources, concludes the report, most likely will increase little or not at all over the rest of this century.
"Conventional sources" means oil in its natural state, pumped up from beneath the earth's surface, plus liquid fuel derived from the production of natural gas. The oil fields of Saudi Arabia or Texas, for example, are conventional sources.
The study does not include oil produced from such formations as Canada's tar sands or US oil shale. Nor does it take into account synthetic fuels to be obtained from coal or biomass. These could be major sources by the year 2000, and could replace some conventional oil supplies.
If the report's conclusions are accurate, noncommunist nations may find themselves in brisker competition for available crude, especially if the Soviet Union and Eastern Europe -- as expected by some experts -- become net importers of oil during the 1980s.
Somber as they are, the findings assume "favorable circumstances" over the next 20 years -- namely, stability in the Middle East and a continued flow of oil from Arab lands.
"Current events in Iran and Iraq," comments Rep. Morris K. Udall (D) of Arizona, "demonstrate that the world oil situation could be far worse than suggested even by OTA's relatively low estimates."
OTA stands for Office of Technology Assessment, an advisory arm of Congress created in 1972 to analyze technological changes and report on them to the nation's lawmakers.
The report foresees steadily declining US output of oil and natural gas liquids, from 10.2 million barrels a day (m.b.d.) in 1979 to a projected range of 4 to 7 m.b.d. in the year 2000.
This tallies with Exxon Corporation's recently published World Energy Outlook , which forecasts a US production level of 6.3 m.b.d. by the year 2000.
"It is this prospect [of declining oil output]," says John H. Gibbons, director of OTA, "that lies at the heart of the challenge to science and technology in the 1980s. We must increasingly find ways of substituting human ingenuity for resources that are no longer amply and cheaply available."
For industrialized countries as a group, the OTA study anticipates shrinking output, from 14.9 m.b.d. in 1979 (including the US) to a range of 7.5 to 13 m.b.d. in 2000.
Although North Sea production (Great Britain and Norway) may grow over the next few years, the report says, "this increase will be offset by declining production in the United States."
Bolstered by Mexican potential, the output of non-OPEC developing countries should rise, from last year's 5.1 m.b.d. to a range of 7.5 million to 11.5 million barrels daily by the end of the century.
The size of Mexico's increase, according to the authors of the study, will depend on the extent of Mexico proved reserves (still uncertain) and on political decisions by Mexican officials as to how rapidly to exploit that nation's vast oil potential.
Putting these factors together, the OTA study concludes that OPEC -- the 13 -member Organization of Petroleum Exporting Countries -- will remain indispensable to oil importers through the rest of the century.
OPEC production, which averaged 31.4 mbd in 1979, is estimated by OTA to total 27 to 37 m.b.d. by the year 2000, depending in part on political factors.
Currently, for example, OPEC output is down to about 24 million barrels daily , reflecting the loss of Iranian and Iraqi oil to the world market, as well as earlier production declines by the cartel as a whole.
Even assuming that Iran and Iraq will restore their 3.5 m.b.d. to the export market after the war, the cartel as a whole is likely to set its production level to meet world demand and to keep upward pressure on prices.
Only Saudi Arabia is credited by OTA, as well as by most other authorities, with the technical capacity to expand its oil ouptut significantly in years ahead.
Total oil production by the noncommunist world -- which averaged 51.4 m.b.d. in 1979 -- is expected to range between 42 million and 62 million barrels daily in the year 2000.
This wide discrepancy takes into account conjectural size of certain reserves (those of Mexico and Iraq, for instance), plus political factors that cannot accurately be gauged now.
Physically, the study notes, it might be possible to increase oil production by as much as 33 percent. Few oil-exporting nations, however, have either the financial or political incentive to boost output sharply.