In South Dakota, 8,000 feet below ground, scientists are advancing geothermal technologies with potential to reshape commercial energy use. At the Sanford Underground Research Facility (SURF), a project led by Pacific Northwest National Laboratory (PNNL) is leveraging the extreme underground conditions to conduct critical research on Enhanced Geothermal Systems (EGS). The work is part of the Center for Understanding Subsurface Signals and Permeability (CUSSP), funded by the U.S. Department of Energy.
Unlike traditional geothermal sites, EGS doesn’t rely on natural hot water reservoirs—it creates engineered systems where fluid is injected into hot rock, extracting heat in a controlled loop. While promising, long-term reliability remains an open question. The key challenge: ensuring that these engineered reservoirs stay open and efficient for decades. Over time, underground fractures can clog with minerals, limiting heat transfer and reducing energy output. These are the questions CUSSP is aiming to answer.
The views and opinions expressed are those of the author’s and do not necessarily reflect the official policy or position of C3.
