U.S. DOE Clean Energy Demonstration Program on Current and Former Mine Land – A Review of Geothermal Energy Case Studies and Opportunities

Abstract

The U.S. Department of Energy (DOE) Clean Energy Demonstration on Current and Former Mine Land (CEML) program was established to enable widespread clean energy deployment by demonstrating the technical and economic viability of clean energy projects on current and former mine land. Up to five clean energy projects will be carried out in geographically diverse regions, at least two of which shall be solar projects. These demonstration projects are expected to be replicable, with the knowledge and experience obtained from this first set of projects inspiring other CEML efforts. Geothermal energy is one of the potential technologies being considered. Geothermal systems are often spatially and genetically associated with ore deposits, and in some cases, have been discovered while in search for epithermal mineral resources. A wide range of geothermal applications have been employed at mine land around the world, including: 1) power generation; 2) mineral extraction from geothermal brines; 3) process heating; 4) direct use for other mining operations; 5) direct use for non-mining operations and subsurface energy storage, including geothermal heat pumps. Selected case studies highlighting these applications provide key lessons relating to identifying drivers and barriers to geothermal resource deployment, and can be used to create screening tools for identifying the types and locations of mine land most amenable to utilizing geothermal resources.