Natural gas is an increasingly important source of the world's energy. Estimating future supplies of this valuable commodity is an important economic and strategic endeavor. This paper analyses historical natural gas production trends for the 53 countries that produce virtually all of the world's natural gas. Using a multicyclic Hubbert method, we forecast the world's future supply of natural gas to the year 2050.
Our analysis showed that the world ultimate reserves of conventional natural gas will be around 10,000 Tcf, of which about 7,900 Tcf of gas reserves remains to be recovered at the end of 1997. The world production of natural gas is expected to peak by 2014 at a production rate extending from 2012 until 2017 of approximately 99 Tcf/yr. Based on the 1997 world gas production and the results of this study, the world supply of conventional natural gas will continue for 96 years with reserves depletion rate of 1%/yr.
In his 1956, and later 1980, predictions of U.S. natural gas production, M. King Hubbert1 - 4 used one complete production cycle to forecast production and estimate ultimate recovery of natural gas for the United States. Several authors have shown that Hubbert's model with one production cycle is generally adequate for predicting crude oil production. However, this study shows that, in the case of natural gas production, most countries exhibit two or more Hubbert-type production cycles. These additional cycles apparently result from changing exploration technology, regulations, and economic and/or political events. Using a Hubbert model with a single production cycle did not allow for these factors. We found that most of the 53 countries apparently exhibit multicyclic gas production. To account for additional production cycles we used a modified version of the Hubbert model which is referred to as the "multicyclic Hubbert" model. A nonlinear least-squares regression was used to determine the parameters of the multicyclic model for each country. Exploration data, when available, were used to calibrate country models with production data. We also present a mathematical analysis of the Hubbert model by deriving equations for determining the production rates at inflection points and their time of occurrence on the Hubbert curve. We will demonstrate a graphical technique to verify the results.