DEVELOPMENT OF A TESTING FACILITY AND PROTOCOL TO PERFORM HIGH-PRESSURE AND HIGH-TEMPERATURE QUALIFICATION OF GEOTHERMAL DOWNHOLE TOOLS

Abstract

Energy demand is rapidly increasing, along with the necessity to reduce CO2 emissions in the environment. This is where Geothermal Energy (GE) plays an important role; its availability 98% of the time and independence from weather conditions, to name a few, make GE more attractive than other types of renewable sources like solar or wind hydropower. However, the technical challenges associated with the high-pressure and high-temperature (HPHT) conditions found when performing geothermal operations exposed the necessity to have a robust and reliable design for the tool that aims to be installed in this kind of operation. This study focuses on the design, the development of a testing protocol, and the validation of a zonal isolation tool that is set to be installed in geothermal operations, more precisely, in the Utah FORGE (Frontier Observatory for Research in Geothermal Energy) project.This research reveals critical limitations in the current oil and gas packer testing standard (API 11D1/ISO 14310). It fails to require prolonged thermal cycling or multiple repetitions of these cycles. Studies indicate that packers designed for oil and gas often fail under geothermal HPHT conditions. To address this, a comprehensive HPHT testing protocol was developed to meet Utah FORGE project requirements of 6,000 psi and 240ºC and to test any downhole tool intended for geothermal use purposes. Key findings emerged from exposing the tool to HPHT conditions for over six weeks across four thermal cycles. During those cycles, the tool was heated up to the desired temperature, pressured, and then cooled down. It was demonstrated that the temperature directly influenced the tool's sealing properties, and it remained in good condition after being removed from the casing post-testing. This work underscores the need for specialized testing facilities and protocols for geothermal purposes to ensure tool reliability and advance geothermal technologies, which are vital for energy development demand.