WorldWide Drilling Resource

57 WorldWide Drilling Resource ® FEBRUARY 2019 Making Strides in Geothermal Research Adapted from Information by GEMex The GEMex project is a cooperation initiative between Mexico and the European Union, developed under the umbrella of the Horizon 2020 in Europe and the Fund for Energy Sustainability in Mexico. The project aims to bring together the extended Mexican know-how of discovering, developing, and exploiting geothermal energy systems with a variety of European expertise. The focus is the development of enhanced geothermal systems (EGS) technology, and searching for new approaches to make use of superhot geothermal systems. GEMex is involved with resource assessment, reservoir characterization, and concept development. The project plans to adapt and further develop methods and technologies at two unconventional geothermal sites located in the eastern part of the Trans-Mexican Volcanic Belt. The Acoculco geothermal field is described as a high-temperature geothermal system. Two wells have been drilled and temperatures above 572°F (300°C) at depths below 5900 feet were found, but hardly any fluids. Preliminary studies consider Acoculco a candidate for the application of EGS technologies. Los Humeros geothermal field is currently convention- ally exploited with a geothermal power plant in operation since 1990. Temperatures around 716°F (380°C) were found at depths below 6500 feet. Los Humeros holds the potential of a superhot resource. Research is ongoing to assess drilling into a superhot geothermal system. Work is centered on analysis of various types of drilling data from wells in Los Humeros Geothermal Field to better understand the applied drilling and completion techniques and present a set of recommendations for future deep drilling projects in the area, including drilling below the current productive reservoir. The main focus has been placed on aiding casing design process, determining a safe operating window during drilling, and primary cementing operations and their challenges. In 2018, a joint meeting between the Federal electricity commission (CFE) and International geothermal center Bochum (GZB) took place in Morelia, Mexico. The main aim of the meeting was to understand the technology used in Los Humeros to drill and com- plete high-temperature geothermal wells, investigate potential challenges faced during drilling for such resource, and acquire data registered during drilling and logging activities for further analysis and mitigation of the potential problems in the area. Another workshop was organized in Bochum, Germany, with the main goal of presenting a progress update, determining further steps, as well as analyzing drilling data obtained from CFE. Concerns raised during the workshop were about underbalance drilling technology, managed pressure drilling operations, cementing practices, geomechanical modeling, fracture and pore pressure predictions, post- cementing logging, and cement quality. The workshop emphasized the need of evaluating cementing reports and parameters from primary cementing operations in Los Humeros for a better understanding of cementing operations in Los Humeros, as well as extending geome- chanical modeling carried out by GZB to more wells in the Los Humeros Geothermal Field. GEO