Natural Gas: Introductory Exercises

Four exercises are provided for the student with an introductory interest in resources. They may be completed with the simple model used to study a "thousand year supply" of natural gas.

1. Build and Verify
Build the introductory model in Figure 2 and verify that it generates the results in Figure 3.

2. Simulate Cumulative Production
Add a stock to the model in Figure 2 to keep track of "cumulative production." Define a new converter named "total gas" as the sum of cumulative production, proven reserves and unproven reserves. Then simulate the model to verify that "total gas" remains constant over the simulation.

3. Double the Resource Base
Naill assumes that unproven gas reserves in 1900 were around 1,000 TCF based on the work by Hubbert (1969), but he cautions that other estimates have ranged as high as 2,000 TCF. Run the model in Figure 2 with 2,000 TCF of reserves. How much longer does the simulation run before termination?

4. Comparison with Naill's Conclusion
Recall Naill's (1973, 248) conclusion that a doubling of the unproven resrves would postpone the transition in supply by only around ten years. Do your findings in the previous exercise match his general conclusion?