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MODELLING SUPPLY MUST AVOID TUNNEL VISION
AND WISHFUL THINKING
HOW WE FORECAST
The methodology for all the forecasts involves, wherever
possible, bottom-up
analysis of individual field profiles. Otherwise wells, fields, plays,
basins, countries and/or regions are modelled using extrapolation, interpolation and educated
analysis based on
experience of geology, engineering, and economics in each area.
A more detailed description of the oil forecasting model
can be downloaded as a .pdf file.
Click here to download.
More information on forecasting and global oil and gas
definitions can be found in our public domain publications. Please click
articles to access some
of these. |
Introduction
Energyfiles forecasts are, of course, based on many
assumptions. All forecasts assume a generally stable global political
environment, unrestricted (except by economic conditions) worldwide
growth in oil and gas demand to their peaks and continuing steady
improvements in technology. Production, reserves and recoverable
resources for each country are independently assessed based on global
data and expert judgement.
Geographic scope
At the last count there were 232 independent countries
(including semi-independent territories). Ninety six of these currently produce
oil, condensate, natural gas liquids and/or gas at significant rates.
Several further countries have produced oil in
the past but are now producing
either no oil and/or gas or very little. Others are believed to have the
potential to produce oil and/or gas at significant rates but
have not yet done so. For forecasting purposes all countries have been
included in the analysis.
Fluid scope
All forms of oil and gas are included in global data
sets.
Any hydrocarbon production from wells that remains
naturally a liquid at surface temperatures and pressures is included as
oil even if it has to be artificially recovered from gas. Thus natural gas liquids (NGLs) are included
as oil, even though they must be refined from gas, whilst liquefied
natural gas (LNG) and gas-to-liquids (GTLs) are not included
since they have to be converted. They are included in the gas
figures (volumes prior to conversion).
Most extra-heavy oils (unconventional oils) that are
extractable under a different economic model and time scale to
conventional oils are not directly included in the remaining reserves
and resources numbers. However bitumen (specifically that contained in
the oil (tar) sand belt of Canada and extra-heavy oils located in the
Orinoco Belt of Venezuela), where production may be converted by refining
into liquid synthetic oil (synfuel) are individually analysed and
included in global production and cumulative production figures.
Unconventional oils such as GTLs, coal-to-liquids (CTLs), oil from
shales and biofuels are considered separately.
All gas production from conventional oil fields,
including from tight gas reservoirs that has been marketed as free gas
or LNG has been included. Production of flared and re-injected gas has
not been included directly. Unconventional gases such as Coal Bed
Methane (CBM) are considered separately.
Theory
It has been shown both theoretically and empirically that
oil and gas production, freely extracted from a sedimentary basin, rises
to a peak at a roughly steady rate as new fields come onstream then
begins to decline at a roughly steady hyperbolic rate as the first
fields begin to deplete and the last few are unable to make up the
difference.
Oil production has a relatively sharp peak whilst, in the
past, gas production has tended to form a plateau due to its different
marketing system. Pricing adjustments, technology and the use of earlier
infrastructure that subsidises later output, all act to stretch decline
out creating a skewed distribution. Economic conditions have a profound
affect on the actual shape of the curve with former Soviet countries,
for example, having volatile production histories as their economies
fluctuated.
Production capacity
Production capacity is the volume of oil and/or gas a
field, basin, country, region or the world can produce in a given time
period. Most countries try to produce as much as they can as quickly as
possible. OPEC countries have intermittently artificially restricted oil production to
conserve resources and prop up and stabilise the oil price. The speed at
which new oil is extracted is increasing rapidly under the influence of
new and improved technologies.
Cumulative production is the total volume of oil or gas
up to a given year that has been produced. Numbers for cumulative
production are taken from the source believed to be most reliable. In
most cases this is directly from government figures although
uncertainties arise from different modes of measurement, inclusion of
different fluids and mixed conversions. All uncertainties have been
minimised wherever possible.
Volumes
Although reserves must always be economic for them to be
recovered estimated remaining reserves are taken to be the most likely
amount of oil or gas that has been discovered but not yet produced, and
will be recovered under economic conditions that could exist in the
future if the world remained a stable, comfortable place to live in. If
the world becomes unstable then all economic forecasts, and indeed most
other forecasts become meaningless.
There will always be additional remaining reserves that
will be recovered but such volumes will be insignificant in world terms
and recovered far in the future. There are large uncertainties in
remaining reserves due to conservative, optimistic and poor reporting by
many countries. In a market environment (especially in the USA) proven
reserves are artificially constrained by economics. Proven reserves are
not used in the analysis. Most likely reserves numbers have been
independently assessed by Energyfiles.
Yet -to find resources are estimated here and are
coincident with the views of most major oil companies. However some
analysts believe that the world’s yet-to-find totals are much greater.
The United States Geological Survey (USGS) in particular, report large
oil values, with most of this extra oil available in remote regions with
none or little current production.
In the view of Energyfiles companies
have struggled to find global reserves outside traditional producing
regions for good geological reasons. They have explored almost
everywhere that it is possible to explore. Deep waters and neglected
regions in OPEC and former communist countries provide much of the
yet-to-find oil and gas resources included in the analyses with
some additional oil and gas available in polar regions.
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