Jeremy Boak, Director Center for Oil Shale Technology & Research

Transcription

1 Jeremy Boak, Director Center for Oil Shale Technology & Research

2 Peak of United States oil production predicted many times The United States Geological Survey makes the pessimistic report that our underground reserves are forty percent exhausted and that we probably are near the peak of domestic production Victor Alderson, President of the Colorado School of Mines quoting a United States Bureau of Mines report to the Secretary of the Treasury, in the Colorado School of Mines Quarterly October 1919

3 The Hubbert prediction M. King Hubbert, a Shell geophysicist rightly famous for several important contributions to geosciences Nuclear Energy and the Fossil Fuels, published in early 1956 Recognized that estimates of ultimate cumulative production (Q t ), the area under the production history curve, strongly constrain future production Projected peak of U. S. production in about 1965, based upon best estimate for Q t of ~150 BBO Using Q t of 200 BBO delayed peak until about 1970

4 Hubbert (1956) prediction of U. S. oil production

5 Hubbert (1956) prediction of U. S. oil production OGJ OGJ

6 Other contemprary predictions of U. S. production peak Author President s Materials Production Commission Year of Prediction Predicted Peak Year Ayres Hubbert Ultimate Cumulative Production (BBO)

7 Four logistic (Hubbert) curve fits to 1955 data Production (MMBOPD) Cumulative = 300 BBO Cumulative = 250 BBO Cumulative = 200 BBO Cumulative = 150 BBO U. S. Production U. S. Production

8 Hubbert (1956) prediction for global oil production (Q t = 1250 BBO)

9 Hubbert (1956) prediction for global oil production (current cum. = 1,128 BBO) Global production

10 The Hubbert model (after Deffeyes, Brandt) Oil production controlled by total oil that can be produced, the ultimate cumulative production (Q t ), or initial reserve. Economic, political, and technological effects produce variability, but are not fundamental to the relationship; Production is related to Q t by plotting the ratio (P/Q) of annual production (P) to cumulative production (Q) against cumulative production;

11 The Hubbert model (after Deffeyes, Brandt) Relationship is linear with negative slope and Q-axis intercept at Q t : P/Q = a (a / Q t ) * Q P= annual production; a = P/Q-axis intercept of the P/Q vs. Q plot; Q = cumulative production; Q t = ultimate cumulative production (Qaxis intercept of the P/Q vs. Q plot) Production defined by: P = a * (1 - Q/Q t ) * Q where 1-Q/Q t is the fraction remaining to be produced Recasting the Production equation: P = a * Q (a/q t ) * Q 2

12 Hubbert curve fit to U. S. production from Production (MMBOPD) y = x x R² = U. S. Production Hubbert curve fit Cumulative Production (BBO)

13 Retrospective testing of predictions Using the Hubbert (logistic) curve formulation, fit the curve for each year, using the data up to that year Data sets: Oil and Gas Journal U. S. Historic Production, IHS World Liquids Production, , courtesy of Pete Stark Performance measures: Coefficient of determination (r 2 ) goodness of fit Cumulative production at peak (equal to half of Q t ) Peak date Ten year prediction

14 Goodness of fit to U. S. production data 1.00 Coefficient of Determination (r 2 )

15 Goodness of fit to global production data 1.00 Coefficient of determination (r 2 ) Hubbert 1853 Deffeyes

16 Cum. Production at Peak (BBO) Hubbert curve predictions of U. S. cumulative production at peak Hubbert peak projections U. S. cumulative production 1975 Cumulative 1970 Cumulative Ultimate Cum. Production (BBO)

17 Hubbert curve sometimes produces unrealistic curve fits Production (MMBOPD) U. S. Production U. S. Production, Hubbert curve y = 0.007x x R² = Cumulative Production

18 Hubbert curve predictions of global cumulative production at peak Cum. Production at Peak (BBO) 1,500 1, Global Cumulative Hubbert 1853 Deffeyes Ultimate Cum. Production (BBO)

19 Hubbert curve predictions of U. S. peak date Projected Peak Hubbert projections 1910 Present date 10 years out

20 Hubbert curve predictions of global peak date Peak Date years out Current year 10 years past Hubbert 1853 Deffeyes Year

21 Hubbert curve predictions of U. S. production ten years out 10 U. S. Production 10 Year Hubbert Projection Production (MMBOPD)

22 Hubbert curve predictions of global production ten years out Production (MMBBOPD) Global Production 10 Year Projection Year Projection

23 Hubbert curve and exponential decline curves for U. S. production 10 Daily Production (MMBOPD) 1 y = 2.2x10 21 *e R² = U. S. Annual Production Hubbert U. S. Production Exponential

24 Conclusions Fitting a logistic curve (the Hubbert model) to production data for United States and the world: produces projections of peak cumulative and ultimate cumulative production that generally increase through time, even more than thirty years after the U. S. peak is reached; Produces peak dates: In the past or less than ten years out for nearly every year from the 1880s until the peak is reached, for U. S. and global production Increasing slowly nearly four decades after the U. S. peak Produces predictions for production ten years out that are less than actual production in that year: for all but 2 years from 1897 to 2006 in the U. S. (especially low and variable in the vicinity of the peak) for all but 16 years from for global production

25 Conclusions Hubbert model widely cited, especially in less technical literature (Wikipedia, etc.) No other model has been tested in this manner One other model in preliminary testing More complex models will be harder to test Inherently symmetric models appear unlikely to provide an adequate description of future for U. S. or global production Hubbert model may provide a reasonable floor for predictions 10 years out

26 An alternative model and uncertainty 10 1 MMBOPD 0.1 U. S. Weibull 2006 U. S. Weibull 1980 U. S. Hubbert 2006 U. S. Hubbert 1980 U. S. Production