Technical Framework Assesses Offshore Geothermal Opportunities in Existing Assets

Abstract

_ This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 215504, “An Integrated Technical Framework for Assessing Offshore Geothermal Opportunities in and Around Existing Oil and Gas Assets,” by Kirsten Pasturel, SPE, ZeGen Energy; Valerie Barres‑Montel, TotalEnergies; and William Harrar, Ross Offshore, et al. The paper has not been peer reviewed. _ The complete paper provides an overview of a geothermal assessment project (GAP) completed to assess the geothermal energy resource in and around an operational high-pressure/high-temperature (HP/HT) field on the UK Continental Shelf. The authors demonstrate a new methodology to identify and determine the amount of electrical power that might be realized from the geothermal resource and associated field infrastructure and investigate both existing and future opportunities. Methodology At present, no single system exists for classifying offshore geothermal reserves and resources, so the described methodology was developed to allow measuring and benchmarking of these opportunities in a similar manner to an oil or gas prospect, which was deemed a relevant analog given the offshore context. Geothermal Proven Reserve. The Geothermal Proven Reserve is that which is associated with the currently producing well stock. The reserve value can be calculated by assessing the thermal energy associated with the current production from a given field. These are reserves because they are currently produced to the surface and are equivalent to “Proved Developed Producing.” Geothermal Contingent Resource. The Geothermal Contingent Resource is defined as the nonproducing resource that occurs within the existing well stock and which could be brought into production by way of capital investment in well recompletion or the perforation of additional intervals within an existing wellbore. This classification is similar to “Proved Undeveloped.” Geothermal Prospective Resource. The Geothermal Prospective Resource is defined as the resource that occurs outside of the existing well stock and which would require activities such as the drilling of new wells from surface or the deepening and completion of existing wells in order to produce these resources.