Environmental Engineering Reference
In-Depth Information
national oil companies do not have to be backed up with drilling evidence
(though they frequently are). Moreover, in the case of OPEC member
countries, there has sometimes been a strong motive for governments to
exaggerate their reserves.
For the size of OPEC members' production quotas within the cartel is
supposed to be related to the size of their reserves. The biggest revision
of reserves in history came in 1986-87 from OPEC countries, mainly in
the Middle East. This revision was largely due to internecine OPEC poli-
tics - the re-negotiation of member countries' production quotas - and
had little to do with discovery of new reserves or new appraisal work on
discovered fields. The arbitrary nature of OPEC's reserve upgrades was
highlighted by the fact that in the 1981-2003 period, stated reserves in
OPEC fields increased by eighty percent overall, compared to a thirty
percent reserve rise in non-OPEC fields.
So what's left?
The firmest estimate is, not surprisingly, the smallest. According to the
International Energy Agency, at the end of 2007 another 1-1.1 trillion
barrels of
proven
reserves of oil remained to be extracted. In other words,
we are halfway through the oil - which sounds very much as though the
peak oil moment is upon us.
But remember that “proven” is the category with a ninety percent
chance of being extracted profitably. If you add in probable reserves (with
fifty percent likelihood of profitable extraction), and allowance for nor-
mal (not OPEC-style) reserve growth due to reappraisal of existing fields,
plus an estimate for recoverable oil from fields yet to be discovered, the
IEA believes the world might have as much as 3.5 trillion barrels of “ulti-
mately recoverable conventional resources”.
This already huge number can be doubled to 6.5 trillion barrels, if you
add in unconventional, heavy oil from the swamps of Venezuela, from the
oil sands of Alberta and from the oil shale of the Rockies. This is what the
IEA terms “the total, long-term potentially recoverable oil resource base”.
Nothing if not thorough, the agency says that the addition of coal-to-
liquids and gas-to-liquids techniques could raise potential to nine trillion
barrels. (These two techniques involve a German process - used during
World War II - to produce synthetic liquid fuel out of coal or gas).
But all estimates of unconventional oil production are enormously
dependent on financial and environmentat costs - which are already
irrevocably intertwined and which will grow increasingly so as the twen-
