Stanford Geothermal WorkshopFebruary 9-11, 2026

As demand for cleaner energy sources grows, geothermal operators must maximize production efficiency from geothermal reservoirs used for power and heat generation. One of the critical challenges shared between geothermal and oil and gas reservoirs is thermal short-circuiting, a phenomenon where cooler injected fluids bypass heat exchange processes by flowing directly to production wells via high-permeability pathways or dominant fractures. This issue, reported in projects such as FORGE and Soultz-sous-Forêts, leads to significantly reduced heat extraction efficiency, as fluid flow distribution within the reservoir is suboptimal. While several techniques have been deployed to address thermal short-circuiting, many have resulted in limited success or even adverse effects on production efficiency. Autonomous Flow control devices (AFCDs) offer a promising solution to these challenges. These tools, already proven in reservoir management for oil and gas wells, can optimize geothermal system efficiency by distributing fluid flow more uniformly, increasing contact between injected fluids and heated rock and enhancing heat absorption. This study explores the potential of autonomous flow control technologies in Enhanced Geothermal Systems (EGS) to address thermal short-circuiting and improve reservoir heat management. For the first time, this paper presents the functionality of autonomous flow control devices, designed to regulate the flow of cold and heated water plus steam, under laboratory conditions. Additionally, results from a comprehensive modelling practice that applies this technology to a geothermal system are discussed. The study simulates multiple possible scenarios which under those cold fluids are injected through an injection well into a naturally fractured and/or hydraulically fractured, high-temperature medium, while heated fluid is subsequently produced via a production well. The impacts of a few uncertain parameters and how the devices mitigate the risk associated with such uncertainties are also addressed. The results highlight that the integration of AFCDs significantly mitigates operational inefficiencies by ensuring uniform fluid distribution, reducing thermal short-circuiting, and maintaining stable reservoir conditions. Furthermore, autonomous flow control devices enable dynamic flow regulation, adapting to changing reservoir conditions in real-time. These advancements lead to delayed cold-water breakthrough for four years while improving thermal recovery by up to 16% and significantly improving economics of the projects. This study illustrates that incorporating AFCDs into geothermal systems represents a significant leap in geothermal reservoir management, offering enhanced heat efficiency, improved sustainability, and greater economic viability for geothermal energy projects. The findings underscore the importance of leveraging advanced flow control technologies to meet the growing global demand for renewable energy.

Topic: Emerging Technology