Geothermal Energy Development

The Geothermal Program at Berkeley Lab

The Geothermal Program at the Lawrence Berkeley National Laboratory (LBNL) began in 1973 in response to the national goal of developing alternative energy sources for electrical and nonelectrical applications. The program is currently funded by the U.S. Department of Energy (DOE).

Initially, program activities centered on the geophysical assessment of sites in northern Nevada, design and development of binary fluid conversion processes, and geochemical studies related to brine chemistry, scaling and corrosion. Over time, the focus of DOE's Geothermal Program changed, as did the program at Berkeley Lab. In the early 1980s, LBNL's main activities were in the areas of Reservoir Technology, Subsidence and Seismicity, and Exploration Technology. Later on, the program stressed basic geoscientific research, development of computer codes, reservoir engineering and geophysical instrumentation, and field application of the newly developed tools and methodologies. Special emphasis was given to geothermal reservoir imaging, testing and modeling. Beginning in 1991, a significant effort was directed toward industry assistance, especially in Technology Transfer and understanding the nature and dynamics of The Geysers geothermal field in northern California. At that time, this steamfield had begun to show the effects of overexploitation (that is, reduction of reservoir pressures and changes in the chemistry of the produced steam). More recently, the focus of the work has shifted to other geothermal areas, especially in the Basin and Range Province. At present, the main activities of the LBNL geothermal program are:

• Developing and enhancing computer codes for modeling heat and mass transfer in porous and fractured rock (i.e., simulating physical and chemical processes in geothermal systems; inverting field and laboratory data to obtain reservoir parameters); Applying noble gases and isotopic techniques to determine geothermal fluid sources, differentiate fluid types, monitor injectate return, and identify reservoir processes and fluid flow paths; Evaluating the effectiveness of state-of-the-art, three-dimensional, high-resolution seismic imaging techniques in geothermal areas; Analyzing the behavior of The Geysers field as steam production continues and liquid water injection increases (These studies are mainly in the area of microseismicity and geochemistry); Testing downhole geophysical tools to locate individual fractures and characterize fracture networks in geothermal reservoirs; Measuring in the laboratory, physical properties of cores and fractures and their changes under different flow, pressure and temperature conditions; Providing technical assistance to U.S. industry and government agencies in their activities at home and abroad; Documenting the behavior of geothermal fields under production and injection operations (i.e., field case studies);

• Transferring geothermal technology and disseminating data through workshops, publications, seminars, etc.