The Export Land Model and Two Case Histories
In previous articles posted on The Oil Drum we outlined a simplistic export model for a hypothetical country with Ultimate Recoverable Reserves (URR) of about 38 billion barrels (Gb), labeled the Export Land Model (ELM). The model showed the effect on net exports of a country that hit peak production and started declining at 5% per year. The exporting country consumes 50% of its production, and that consumption is increasing by 2.5% per year. The 5% decline rate is loosely based on the post-peak Texas decline rate of about 4% per year. The ELM is shown graphically below, Figure One.
First, assuming ultimate recoverable reserves of 38 Gb, and assuming that Export Land peaked when it was about 55% depleted, Export Land would have about 17 Gb of remaining recoverable reserves, after peaking. The model shows that only about 1.7 Gb, or 10%, of remaining post-peak recoverable reserves would be exported.
Second, the overall exponential net export decline rate, about 29% per year over the eight year net export decline period, is much more rapid than the production decline rate of 5% per year, because net exports in a given year are the net difference between two exponential functions: exponentially declining production and (generally) exponentially increasing consumption.
Third, the net export decline rate in a given year accelerates with time, from an initial year over year change in net exports of -12.5% to a final year over year change in net exports of -47.6% (last year of net exports). So, how does the simplistic ELM compare to real world case histories? Actually, two recent case histories, Indonesia and the UK, showed sharper net export declines than the ELM. Figure Two, shows the year-over-year changes in net exports, from the start of the most recent production declines to the (apparent) final year of net exports (EIA, Total Liquids).
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