The Berkeley Lab Geothermal Systems Program has been recommended for funding for two projects under a recent announcement by the DOE Geothermal Technology Office of a total of $12M in funding for seven research projects to advance the commercialization of enhanced geothermal systems. The first is led by EESA staff scientist Seiji Nakagawa, with collaborators from Sandia National Laboratories, Baker Hughes, and the Geothermal Resources Group, Inc. The second is a project led by Montana State University, with Eric Sonnenthal as Berkeley Lab collaborator.
Project Led by Berkeley Lab (PI Seiji Nakagawa): Reversible Reservoir Permeability Modification Via In-situ Formation of Silicate Gel Plugs from Micro/Nano-Encapsulated Reactant Fluids
Location: Berkeley, California
DOE Award: $1.7 million
Project Summary: The project’s proposed technology uses hydrated silicate gel formed by reaction of microencapsulated chemicals for reversible alteration of EGS reservoir permeability. Flow-diverting plugs can be created away from wells by delivering one or both of the reactants within encapsulated micro (or nano) particles. The timing of the capsule’s shell degradation is used to control the release of the contents. The finite particle size limits entry into narrow fractures and pores, targeting fast flow paths naturally preferred by the fluid flow. The proposed research will establish this technology by (1) identifying optimal combinations of gel-forming chemicals; (2) producing and characterizing the behavior of encapsulated microparticles; and (3) verifying and demonstrating the technology in the laboratory via scaled experiments.
Project led by Montana State University (Berkeley Lab collaborator Eric Sonnenthal): Thermally Induced Calcite Precipitation (TICP) as a Method to Control Hydraulic Properties in Enhanced Geothermal Systems
Location: Bozeman, Montana
DOE Award: $1.5 million
Project Summary: Under high temperatures, the mineral precipitation process promotes the production of carbonate minerals, which can result in the reduction of permeability. The goal of this project is to investigate thermally induced calcium carbonate precipitation and facilitate technologies that can control the location and magnitude of associated permeability reduction within EGS fracture networks. The proposed effort combines experimental work in the laboratory with computational reservoir scale modeling.
More detailed information can be found here.