Geothermal Resource Proving Criteria

Abstract

The great expansion of geothermal development, and in the number of geothermal developers, during the 1990s, led to the need to formally define geothermal reserves. Such definition occurs at a project milestone, such as bank finance approval, or to enable an oil company to add reserves to its assets, or when a project is sold; as well as the more obvious traditional need to size a power station. At the same time technology and experience has grown rapidly. The development of reservoir simulation has been spurred by both software development and practical experience. It is now the case that reservoir simulation provides in most cases a reliable and proven technology for resource assessment, and is clearly superior to lumped-parameter estimates such as stored heat, and the cost of reservoir simulation is now reasonable. The superiority is so clear that it is difficult to justify the use of any other method to provide an estimate to the reserves available from a geothermal resource. Possible exceptions include small projects using only part of a resource.