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A geothermal resource data base: New Mexico

Description: This report provides a compilation of geothermal well and spring information in New Mexico up to 1993. Economically important geothermal direct-use development in New Mexico and the widespread use of personal computers (PC) in recent years attest to the need for an easily used and accessible data base of geothermal data in a digital format suitable for the PC. This report and data base are a part of a larger congressionally-funded national effort to encourage and assist geothermal direct-use. In 1991, the US Department of Energy, Geothermal Division (DOE/GD) began a Low Temperature Geothermal Resources and Technology Transfer Program. Phase 1 of this program includes updating the inventory of wells and springs of ten western states and placing these data into a digital format that is universally accessible to the PC. The Oregon Institute of Technology GeoHeat Center (OIT) administers the program and the University of Utah Earth Sciences and Resources Institute (ESRI) provides technical direction.
Date: July 1, 1995
Creator: Witcher, J.C.
Partner: UNT Libraries Government Documents Department

Geothermal regimes of the Clearlake region, northern California

Description: The first commercial production of power from geothermal energy, at The Geysers steamfield in northern California in June 1960, was a triumph for the geothermal exploration industry. Before and since, there has been a search for further sources of commercial geothermal power in The Geysers--Clear Lake geothermal area surrounding The Geysers. As with all exploration programs, these were driven by models. The models in this case were of geothermal regimes, that is, the geometric distribution of temperature and permeability at depth, and estimates of the physical conditions in subsurface fluids. Studies in microseismicity and heat flow, did yield geophysical information relevant to active geothermal systems. Studies in stable-element geochemistry found hiatuses or divides at the Stoney Creek Fault and at the Collayomi Fault. In the region between the two faults, early speculation as to the presence of steamfields was disproved from the geochemical data, and the potential existence of hot-water systems was predicted. Studies in isotope geochemistry found the region was characterized by an isotope mixing trend. The combined geochemical data have negative implications for the existence of extensive hydrothermal systems and imply that fluids of deep origin are confined to small, localized systems adjacent to faults that act as conduits. There are also shallow hot-water aquifers. Outside fault-localized systems and hot-water aquifers, the area is an expanse of impermeable rock. The extraction of energy from the impermeable rock will require the development and application of new methods of reservoir creation and heat extraction such as hot dry rock technology.
Date: June 1, 1998
Creator: Amador, M.; Burns, K.L. & Potter, R.M.
Partner: UNT Libraries Government Documents Department

Advanced biochemical processes for geothermal brines: Current developments

Description: A research program at Brookhaven National Laboratory (BNL) which deals with the development and application of processes for the treatment of geothermal brines and sludges has led to the identification and design of cost-efficient and environmentally friendly treatment methodology. Initially the primary goal of the processing was to convert geothermal wastes into disposable materials whose chemical composition would satisfy environmental regulations. An expansion of the r and D effort identified a combination of biochemical and chemical processes which became the basis for the development of a technology for the treatment of geothermal brines and sludges. The new technology satisfies environmental regulatory requirements and concurrently converts the geothermal brines and sludges into commercially promising products. Because the chemical composition of geothermal wastes depends on the type of the resource, the emerging technology has to be flexible so that it can be readily modified to suit the needs of a particular type of resource. Recent conceptional designs for the processing of hypersaline and low salinity brines and sludges will be discussed.
Date: July 7, 1997
Creator: Premuzic, E.T.; Lin, M.S.; Bohenek, M.; Bajsarowicz, V. & McCloud, M.
Partner: UNT Libraries Government Documents Department

Water adsorption at high temperature on core samples from The Geysers geothermal field

Description: The quantity of water retained by rock samples taken from three wells located in The Geysers geothermal reservoir, California, was measured at 150, 200, and 250 C as a function of pressure in the range 0.00 {le} p/p{sub 0} {le} 0.98, where p{sub 0} is the saturated water vapor pressure. Both adsorption (increasing pressure) and desorption (decreasing pressure) runs were made in order to investigate the nature and the extent of the hysteresis. Additionally, low temperature gas adsorption analyses were performed on the same rock samples. Nitrogen or krypton adsorption and desorption isotherms at 77 K were used to obtain BET specific surface areas, pore volumes and their distributions with respect to pore sizes. Mercury intrusion porosimetry was also used to obtain similar information extending to very large pores (macropores). A qualitative correlation was found between the surface properties obtained from nitrogen adsorption and the mineralogical and petrological characteristics of the solids. However, there is in general no proportionality between BET specific surface areas and the capacity of the rocks for water adsorption at high temperatures. The results indicate that multilayer adsorption rather than capillary condensation is the dominant water storage mechanism at high temperatures.
Date: June 1, 1998
Creator: Gruszkiewicz, M.S.; Horita, J.; Simonson, J.M. & Mesmer, R.E.
Partner: UNT Libraries Government Documents Department

Water adsorption at high temperature on core samples from The Geysers geothermal field

Description: The quantity of water retained by rock samples taken from three wells located in The Geysers geothermal field, California, was measured at 150, 200, and 250 C as a function of steam pressure in the range 0.00 {le} p/p{sub 0} {le} 0.98, where p{sub 0} is the saturated water vapor pressure. Both adsorption and desorption runs were made in order to investigate the extent of the hysteresis. Additionally, low temperature gas adsorption analyses were made on the same rock samples. Mercury intrusion porosimetry was also used to obtain similar information extending to very large pores (macropores). A qualitative correlation was found between the surface properties obtained from nitrogen adsorption and the mineralogical and petrological characteristics of the solids. However, there was no direct correlation between BET specific surface areas and the capacity of the rocks for water adsorption at high temperatures. The hysteresis decreased significantly at 250 C. The results indicate that multilayer adsorption, rather than capillary condensation, is the dominant water storage mechanism at high temperatures.
Date: June 1, 1998
Creator: Gruszkiewicz, M.S.; Horita, J.; Simonson, J.M. & Mesmer, R.E.
Partner: UNT Libraries Government Documents Department

High temperature spectral gamma well logging

Description: A high temperature spectral gamma tool has been designed and built for use in small-diameter geothermal exploration wells. Several engineering judgments are discussed regarding operating parameters, well model selection, and signal processing. An actual well log at elevated temperatures is given with spectral gamma reading showing repeatability.
Date: January 1, 1997
Creator: Normann, R.A. & Henfling, J.A.
Partner: UNT Libraries Government Documents Department

Microbial dissolution of silicate materials. Final report

Description: The objective of this research was to better understand the role of selected thermophilic bacteria in the colonization and dissolution of silicate minerals, with potential applications to the HDR Project. The demonstration of enhanced dissolution from microbial effects is critically dependent on providing a mineral bait within a media deficient in the critical nutrient found in the mineral (e.g., Fe). Reproducible experimental conditions in batch experiments require agitation to expose mineral powders, as well as nearly similar initial conditions for both inoculated cultures and controls. It is difficult, but not impossible to ensure reproducible conditions with microbes favoring filamentous growth habits.
Date: March 26, 1996
Creator: Schwartzman, D.
Partner: UNT Libraries Government Documents Department

Renewable energy annual 1998, with data for 1997

Description: This is the fourth annual report published by the Energy Information Administration (EIA) which presents information on renewable energy consumption, capacity, and electricity generation data; US solar thermal and photovoltaic collector manufacturing activities; and US geothermal heat pump manufacturing activities. It updates and provides more detail on renewable energy information than what`s published in the Energy Information Administration`s (EIA) Annual Energy Review 1997. The renewable energy resources included in the report are: biomass (wood, wood waste, municipal solid waste, ethanol, and biodiesel); geothermal; wind; solar (solar thermal and photovoltaic); and hydropower. However, hydropower is also regarded as a conventional energy source because it has furnished a significant amount of electricity for more than a century. Therefore, the contribution of hydropower to total renewable energy consumption is discussed, although hydropower as an individual energy source is not addressed. Since EIA collects data only on terrestrial (land-based) systems, satellite and military applications are not included in this report. 13 figs., 44 tabs.
Date: December 1, 1998
Partner: UNT Libraries Government Documents Department

Recommendations report for the platanares geothermal site, Department of Copan, Honduras. Reporte de recomendaciones para el sitio geotermico de platanares, Departamento de Copan, Honduras

Description: A geothermal assessment of six previously identified sites in Honduras has been conducted by a team comprised of staff from the Los Alamos National Laboratory, the US Geological Survey, and the Empresa Nacional de Energia Electrica. The application of both reconnaissance and detailed scale techniques lead to the selection of Platanares in the Department of Copan as the highest potential site. Additional work resulted in the completion of a prefeasibility study at Platanares. We present here a tabulation of the work completed and short summaries of the results from these technical studies. We also present a brief model of the geothermal system and recommendations for additional feasibility work. Both English and Spanish versions of this report are provided in the same document. 18 figs., 5 tabs.
Date: November 1, 1988
Partner: UNT Libraries Government Documents Department

Transport in porous and fractured media of the Creede Formation

Description: Direct measurement was made of the hydraulic conductivity of Creede Formation rocks using a new experimental method. The UFA{trademark} method employs open-flow centrifugation. Centrifugation, like gravity, has the effect on a material of a whole-body force exerting equal force at all points within the sample. The equivalent gravitational force exerted throughout the sample can be chosen to be from one to four orders of magnitude higher than earth gravity (from 10 to 10,000 g). The result is an increase in rate of fluid flow equally at all points throughout the sample so that hydraulic steady state is obtained in most geologic materials in hours, even under highly unsaturated conditions. This extraordinarily short time allows direct measurement of transport parameters, such as hydraulic conductivity, diffusion coefficient, and retardation factors, in any porous media over the complete range of field moisture contents. Hydraulic conductivities in the Creede Formation rocks ranged from 10{sup {minus}12} cm/s to 10{sup {minus}7} cm/s (10{sup {minus}9} Darcy to 10{sup {minus}4} Darcy) and showed no correlation with any other physical or mineralogical properties including porosity. The high degree of alteration to clay minerals appears to obscure any porosity/permeability relationship of the kind that occurs in many reservoir rocks. However, down-hole neutron porosities correlated well with laboratory-determined porosities. The objective of this investigation is to determine the hydrologic transport parameters of Creede Formation rocks for use in transport model development and for image analysis of transport pathways to produce a porosity/permeability evolution curve in support of geochemical and isotopic water/rock interaction models.
Date: December 31, 1995
Creator: Conca, J. L.
Partner: UNT Libraries Government Documents Department

Geothermal heat pumps at Fort Polk: Early results

Description: At Fort Polk, LA an entire city (4,003 military family housing units) is being converted to geothermal heat pumps (GHP) under a performance contract. At the same time other efficiency measures such as compact fluorescent lights (CFLs), low-flow water outlets, and attic insulation are being installed. If these contracts and this technology are to be used widely in US Department of Defense (DoD) facilities and other public buildings, better data from actual projects is the key. Being the first GHP project of this type and size, Fort Polk proved to be very challenging for all concerned. To get from RFP to start of construction took several years. This hard work by others created a once-in-a-lifetime opportunity to address many of the due diligence issues that delayed the Fort Polk project. So that future projects can move faster, an evaluation has been undertaken to address the following barriers: absence of a documented large-scale demonstration of GHP energy, demand, and maintenance savings (a barrier to acceptance by federal customers, performance contractors, and investors); newness of large-scale facility capital renewal procurements at federal facilities under energy savings performance contracts (ESPCs) or traditional appropriations (lack of case studies); and variability in current GHP design tools (increases risks and costs for federal customers, performance contractors, investors and designers). This paper presents early energy and demand savings results based on data collection through January 1996.
Date: December 31, 1996
Creator: Hughes, P.J. & Shonder, J.A.
Partner: UNT Libraries Government Documents Department

Thermally conductive cementitious grouts for geothermal heat pumps. Progress report FY 1998

Description: Research commenced in FY 97 to determine the suitability of superplasticized cement-sand grouts for backfilling vertical boreholes used with geothermal heat pump (GHP) systems. The overall objectives were to develop, evaluate and demonstrate cementitious grouts that could reduce the required bore length and improve the performance of GHPs. This report summarizes the accomplishments in FY 98. The developed thermally conductive grout consists of cement, water, a particular grade of silica sand, superplasticizer and a small amount of bentonite. While the primary function of the grout is to facilitate heat transfer between the U-loop and surrounding formation, it is also essential that the grout act as an effective borehole sealant. Two types of permeability (hydraulic conductivity) tests was conducted to evaluate the sealing performance of the cement-sand grout. Additional properties of the proposed grout that were investigated include bleeding, shrinkage, bond strength, freeze-thaw durability, compressive, flexural and tensile strengths, elastic modulus, Poisson`s ratio and ultrasonic pulse velocity.
Date: November 1, 1998
Creator: Allan, M.L. & Philippacopoulos, A.J.
Partner: UNT Libraries Government Documents Department

Development of a geothermal resource in a fractured volcanic formation: Case study of the Sumikawa Geothermal Field, Japan

Description: The principal purpose of this case study of the Sumikawa Geothermal Field is to document and to evaluate the use of drilling logs, surface and downhole geophysical measurements, chemical analyses, and pressure transient data for the assessment of a high temperature volcanic geothermal field. The work accomplished during Year 1 of this ongoing program is described in the present report. A brief overview of the Sumikawa Geothermal Field is given. The drilling information and downhole pressure, temperature, and spinner surveys are used to determine feedzone locations, pressures and temperatures. Available injection and production data from both slim holes and large-diameter wells are analyzed to evaluate injectivity/productivity indices and to investigate the variation of discharge rate with borehole diameter. Finally, plans for future work are outlined.
Date: November 1, 1996
Creator: Garg, S.K.; Pritchett, J.W.; Stevens, J.L.; Luu, L. & Combs, J.
Partner: UNT Libraries Government Documents Department

Application of inverse modeling to geothermal reservoir simulation

Description: The authors have developed inverse modeling capabilities for the non-isothermal, multiphase, multicomponent numerical simulator TOUGH2 to facilitate automatic history matching and parameter estimation based on data obtained during testing and exploitation of geothermal fields.The ITOUGH2 code allows one to estimate TOUGH2 input parameters based on any type of observation for which a corresponding simulation output can be calculated. Furthermore, a detailed residual and error analysis is performed, and the uncertainty of model predictions can be evaluated. Automatic history matching using ITOUGH2 is robust and efficient so that model parameters affecting geothermal field performance can reliably be estimated based on a variety of field measurements such as pressures, temperatures, flow rates, and enthalpies. The paper describes the methodology of inverse modeling and provides a detailed discussion of sample problems to demonstrate the application of the method to data from geothermal reservoirs.
Date: January 1, 1997
Creator: Finsterle, S.; Pruess, K.; Bullivant, D.P. & O`Sullivan, M.J.
Partner: UNT Libraries Government Documents Department

Minewater heat recovery project. Final technical report -- Research overview

Description: This report describes the work carried out for the development of a downhole bundle heat exchanger for heat recovery from mine water. The temperature of water flowing through mine shafts remains essentially constant at approximately 60 F throughout the year. Therefore, it is warmer than the working fluid in the heating season and colder than the working fluid in the cooling season. In addition, it is available at zero fuel cost, thus making it an ideal candidate for space-conditioning applications. The heat transfer performance of the heat exchanger in a constant temperature water reservoir was studied and experimentally evaluated by installing the heat exchanger in the mine water shafts at Scranton, Pennsylvania and also subsequently at the Ohio State University and the lake at Lackawanna State Park. All these sites provided a stationary water column for installing a heat exchanger, where heat exchange through natural convection could be obtained. Depending on the requirements of the system cycle the heat exchanger could either function on the heating or cooling modes of operation. In tests, spanning over a period of many months, the performance of the downhole bundle heat exchanger was evaluated for both cooling and heating modes of operation.
Date: April 1, 1992
Partner: UNT Libraries Government Documents Department

Thermal conductivity of cementitious grouts for geothermal heat pumps. Progress report FY 1997

Description: Grout is used to seal the annulus between the borehole and heat exchanger loops in vertical geothermal (ground coupled, ground source, GeoExchange) heat pump systems. The grout provides a heat transfer medium between the heat exchanger and surrounding formation, controls groundwater movement and prevents contamination of water supply. Enhanced heat pump coefficient of performance (COP) and reduced up-front loop installation costs can be achieved through optimization of the grout thermal conductivity. The objective of the work reported was to characterize thermal conductivity and other pertinent properties of conventional and filled cementitious grouts. Cost analysis and calculations of the reduction in heat exchanger length that could be achieved with such grouts were performed by the University of Alabama. Two strategies to enhance the thermal conductivity of cementitious grouts were used simultaneously. The first of these was to incorporate high thermal conductivity filler in the grout formulations. Based on previous tests (Allan and Kavanaugh, in preparation), silica sand was selected as a suitable filler. The second strategy was to reduce the water content of the grout mix. By lowering the water/cement ratio, the porosity of the hardened grout is decreased. This results in higher thermal conductivity. Lowering the water/cement ratio also improves such properties as permeability, strength, and durability. The addition of a liquid superplasticizer (high range water reducer) to the grout mixes enabled reduction of water/cement ratio while retaining pumpability. Superplasticizers are commonly used in the concrete and grouting industry to improve rheological properties.
Date: November 1997
Creator: Allan, M. L.
Partner: UNT Libraries Government Documents Department

Electrical energy and demand savings from a geothermal heat pump energy savings performance contract at Ft. Polk, LA

Description: At Fort Polk, LA the space conditioning systems of an entire city (4,003 military family housing units) have been converted to geothermal heat pumps (GHP) under an energy savings performance contract. At the same time, other efficiency measures such as compact fluorescent lights (CFLs), low-flow hot water outlets, and attic insulation were installed. Pre- and post-retrofit data were taken at 15-minute intervals on energy flows through the electrical distribution feeders that serve the family housing areas of the post. 15-minute interval data was also taken on energy use from a sample of the residences. This paper summarizes the electrical energy and demand savings observed in this data. Analysis of feeder-level data shows that for a typical year, the project will result in a 25.6 million kWh savings in electrical energy use, or 32.4% of the pre-retrofit electrical consumption in family housing. Results from analysis of building-level data compare well with this figure. Analysis of feeder-level data also shows that the project has resulted in a reduction of peak electrical demand of 6,541 kW, which is 39.6% of the pre-retrofit peak electrical demand. In addition to these electrical savings, the facility is also saving an estimated 260,000 therms per year of natural gas. It should be noted that the energy savings presented in this document are the apparent energy savings observed in the monitored data, and are not to be confused with the contracted energy savings used as the basis for payments. To determine the contracted energy savings, the apparent energy savings may require adjustments for such things as changes in indoor temperature performance criteria, additions of ceiling fans, and other factors.
Date: June 1, 1997
Creator: Shonder, J.A. & Hughes, P.J.
Partner: UNT Libraries Government Documents Department

Minewater heat recovery project. Final Technical report

Description: This report consists of three sections: (1) Design, experimental testing and performance analysis of the 20-ft long DBHE (Downhole Bundle Heat Exchanger); (2) Modified design of mine water heat exchanger; and (3) Performance tests on mine water heat exchanger. Appendices summarize design calculations, discuss the scope of the work tasks, and present a diary of the progress throughout the research and development project.
Date: April 1, 1992
Partner: UNT Libraries Government Documents Department

A database for the Geysers geothermal field

Description: This document contains graphs of data collected from Geysers Geothermal Field. These graphs display data concerning steam rate and cumulative steam from 1968 to 1988. 245 figs. (FSD)
Date: September 1, 1989
Creator: Bodvarsson, G.S.; Cox, B.L.; Fuller, P.; Ripperda, M.; Tulinius, H.; Witherspoon, P.A. et al.
Partner: UNT Libraries Government Documents Department

High-energy gas fracturing in cased and perforated wellbores

Description: A propellant-based technology, High-Energy Gas Fracturing (HEGF), has been applied to fracturing through perforations in cased boreholes. HEGF is a tailored-pulse fracturing technique originally developed by Sandia National Laboratories for application in uncased, liquid-free gas wells in Appalachian Devonian shales. Because most oil and gas wells are liquid filled as well as cased and perforated, the potential impact of present research is significantly broader. A number of commercial tailored-pulse fracturing services, using a variety of explosives or propellants, are currently available. Present research provides valuable insight into phenomena that occur in those stimulations. The use of propellants that deflagrate or burn rather than detonate, as do high-order explosives, permits controlled buildup of pressure in the wellbore. The key to successful stimulation in cased and perforated wellbores is to control the pressure buildup of the combustion gases to maximize fracturing without destroying the casing. Eight experiments using cased and perforated wellbore were conducted in a tunnel complex at the Department of Energy's Nevada Test Site, which provides a realistic in situ stress environment (4 to 10 MPa (600 to 1500 psi)) and provides access for mineback to directly observe fracturing obtained. Primary variables in the experiments include propellant burn rate and amount of propellant used, presence or absence of liquid in the wellbore, in situ stress orientation, and perforation diameter, density, and phasing. In general, the presence of liquid in the borehole results in a much faster pressure risetime and a lower peak pressure for the same propellant charge. Fracture surfaces proceed outward along lines of perforations as determined by phasing, then gradually turn toward the hydraulic fracture direction. 8 refs., 23 figs., 3 tabs.
Date: June 1, 1986
Creator: Cuderman, J.F.
Partner: UNT Libraries Government Documents Department

Paraho environmental data. Part I. Process characterization. Par II. Air quality. Part III. Water quality

Description: From 1973 to 1978, Development Engineering, Inc. (DEI), a subsidiary of Paraho Development Corporation, demostrated the Paraho technology for surface oil shale retorting at Anvil Points, Colorado. A considerable amount of environmentally-related research was also conducted. This body of data represents the most comprehensive environmental data base relating to surface retorting that is currently available. In order to make this information available, the DOE Office of Environment has undertaken to compile, assemble, and publish this environmental data. The compilation has been prepared by DEI. This report includes the process characterization, air quality, and water quality categories.
Date: June 1, 1980
Creator: Heistand, R.N.; Atwood, R.A. & Richardson, K.L.
Partner: UNT Libraries Government Documents Department

Flora of the Mayacmas Mountains. [Listing of 679 species in the Geysers Geothermal Resource area]

Description: This flora describes the plants that occur within the Mayacmas Mountain Range of northern California. It is the result of ten years of environmental assessment by the author in the Geysers Geothermal Resource area, located in the center of the Mayacmas Range. The flora includes notes on plant communities and ecology of the area, as well as habitat and collection data for most of the 679 species covered. Altogether 74 families, 299 genera and 679 species are included in the flora. The work is divided into eight subdivisions: trees; shrubs; ferns and fern allies; aquatic plants; tules, sedges, and rushes; lilies and related plants; dicot herbs; and grasses. Within each subdivision, family, genera and species are listed alphabetically. Keys are provided at the beginning of each subdivision. A unique combination of physical, environmental and geologic factors have resulted in a rich and diverse flora in the Mayacmas. Maps have been provided indicating known locations for species of rare or limited occurrence.
Date: September 1, 1981
Creator: Neilson, J.A.
Partner: UNT Libraries Government Documents Department