Estimates of Worldwide Gas Hydrate Resources

Abstract Gas hydrates have been touted as the next generation of energy resources exploitable for commercial gain and anthropogenic use. It would then seem relevant to estimate the potential resources available in order that one has an appreciation of availability. Several such estimates have been made over the years for both onshore and offshore gas hydrates. This paper examines the relative percentages and the ranges of uncertainty for both the onshore and offshore estimates. In addition, the estimated resources are plotted versus the year in which the estimate was made to see if any convergence of results is being achieved with time as more data become available. The main conclusions are that there seems not to be any systematic pattern of convergence of resource estimates with time, nor does there seem to be any narrowing of the uncertainty of the estimates for either onshore or offshore resource estimates as more data have become available over the last twenty years. It would seem that a concerted effort is needed to improve estimates if there is to be any hope of assessing the commercial worth of hydrate resources and of deciding whether hydrates really do represent a significant exploitable energy resource on a worldwide basis. Introduction As a cleaner energy source than hydrocarbons, gas hydrates have often been advertised as an appropriate alternative. The fundamental question is whether there is a sufficient resource of gas hydrates, on a worldwide basis, to act as a dominant energy source for the future. To be sure there are also technical problems of extraction and production of hydrates, once found, be it in the onshore or offshore regions. But the technical and commercial risk problems are secondary in the sense that unless there is a sufficient worldwide resource of gas hydrates, then technical methods will not be developed to exploit a constrained limited resource. There would be no profit in so doing. Likewise, even if technical extraction methods already existed, there would be no worldwide xploitation of gas hydrates if the costs of involvement and recovery were to rise to a point were no profit could be made-much as happens with oil and gas fields today, which are often not produced because of too high a cost relative to potential gains. So the sine qua non is to first estimate the resources available. Indeed, this aspect has been recognized as the ultimate driver of potential further developments for over twenty years now (Kaplan, 1974). And, as new information has become available over the years, such has been incorporated in estimates of worldwide resources of gas hydrates both onshore and offshore. Since the early 1990's, after the dissolution of the Soviet bloc, much information has become available that heretofore was the exclusive province of the Soviet Union and/ or the intelligence gathering agencies of the world - most notably the CIA in America.