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1

Rock-Water Interactions In Hot Dry Rock Geothermal Systems- Field...  

Open Energy Info (EERE)

Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon Rock-Water Interactions In Hot Dry Rock Geothermal Systems- Field Investigations Of In Situ...

2

Rock-Water Interactions In Hot Dry Rock Geothermal Systems- Field  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Rock-Water Interactions In Hot Dry Rock Geothermal Systems- Field Investigations Of In Situ Geochemical Behavior Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Rock-Water Interactions In Hot Dry Rock Geothermal Systems- Field Investigations Of In Situ Geochemical Behavior Details Activities (5) Areas (2) Regions (0) Abstract: Two hot dry rock (HDR) geothermal energy reservoirs have been created by hydraulic fracturing of Precambrian granitic rock between two wells on the west flank of the Valles Caldera in the Jemez Mountains of northern New Mexico. Heat is extracted by injecting water into one well,

3

Energy extraction characteristics of hot dry rock geothermal systems  

DOE Green Energy (OSTI)

The LASL Hot Dry Rock Geothermal Energy Project is investigating methods to extract energy at useful temperatures and rates from naturally heated crustal rock in locations where the rock does not spontaneously yield natural steam or hot water at a rate sufficient to support commercial utilization. Several concepts are discussed for application to low and high permeability formations. The method being investigated first is intended for use in formations of low initial permeability. It involves producing a circulation system within the hot rock by hydraulic fracturing to create a large crack connecting two drilled holes, then operating the system as a closed pressurized-water heat-extration loop. With the best input assumptions that present knowledge provides, the fluid-flow and heat-exchange calculations indicate that unpumped (buoyant) circulation through a large hydraulic fracture can maintain a commercially useful rate of heat extraction throughout a usefully long system life. With a power cycle designed for the temperature of the fluid produced, total capital investment and generating costs are estimated to be at least competitive with those of fossil-fuel-fired and nuclear electric plants. This paper discusses the potential of the hot dry rock resource, various heat extraction concepts, prediction of reservoir performance, and economic factors, and summarizes recent progress in the LASL field program.

Tester, J.W.; Smith, M.C.

1977-01-01T23:59:59.000Z

4

Characterization of hot dry rock geothermal energy extraction systems  

DOE Green Energy (OSTI)

The engineering of heat exchange systems by which geothermal heat can be efficiently extracted from hot impermeable rocks is studied. The system currently under investigation at Fenton Hill, New Mexico consists of a network of large fractures created through the hydraulic pressurization of a well penetrating hot basement rocks and subsequently intersected by a second well drilled to form a flow-thru system. Cool water pumped into the fractures through one well, once heated in the reservoir, returns to the surface through the second well, is cooled, and then recirculated. While much is known about the performance parameters of the fracture network from short-term flow tests, little is understood concerning the spatial dimensions and geometrical relationship of individual fractures comprising the network. Ultimately, the success one has in estimating the long-term performance of such a system where commercialization is an issue, and in engineering future systems with optimal performance, depends on the success in characterizing the flow-thru fracture networks. To date only nonconventional application of oil field logging techniques and acoustic emissions studies have been used in the characterization of the fracture network.

Albright, J.N.; Newton, C.A.

1981-01-01T23:59:59.000Z

5

Modeling brine-rock interactions in an enhanced geothermal system deep fractured reservoir at Soultz-Sous-Forets (France): a joint approach using two geochemical codes: frachem and toughreact  

E-Print Network (OSTI)

rock interactions in enhanced geothermal systems (EGS).31 th Workshop on Geothermal Reservoir Engineering, 301998). Computer modeling for geothermal systems: predicting

Andre, Laurent; Spycher, Nicolas; Xu, Tianfu; Vuataz, Francois-D.; Pruess, Karsten.

2006-01-01T23:59:59.000Z

6

A History Of Hot Dry Rock Geothermal Energy Systems | Open Energy  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » A History Of Hot Dry Rock Geothermal Energy Systems Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: A History Of Hot Dry Rock Geothermal Energy Systems Details Activities (1) Areas (1) Regions (0) Abstract: This is a short history, so far as it can now be assembled, of early speculations and observations concerning the existence and origin of natural heat in the earth's crust; of some of the many methods proposed to extract and use it; and of recent investigations designed to develop and demonstrate such methods. It is probably only the preface to a much longer

7

Technical and cost analysis of rock-melting systems for producing geothermal wells. [GEOWELL  

DOE Green Energy (OSTI)

The drilling of wells makes up a large fraction of the costs of geothermal energy-extraction plants, and billions of dollars for wells will be needed before geothermal energy is nationally significant. Technical and economic systems studies are summarized regarding the application of the Subterrene concept, i.e., excavating and penetrating rocks or soils by melting, to the production of deep wells such as may be used for dry hot rock or geopressurized geothermal energy-extraction systems. Technically, it was found that Subterrene features are compatible with those of current rotary drilling practices. In fact, some special features could lead to improved well production techniques. These include the buildup of a glass lining along the borehole wall which provides structural resistance to collapse; close control of hole geometry; the existence of a barrier between the drilling fluids and the formations being penetrated; nonrotation; potentially better bit life; and faster rates of penetration in deep, hard rock. A typical optimum-cost well would be rotary-drilled in the upper regions and then rock-melted to total depth. Indicated cost savings are significant: a 30 percent or 3.9 million dollar (1975 $) reduction from rotary-drilled well costs are estimated for a 10-km depth well with a bottom hole temperature of 673 K. Even for relatively cool normal geothermal gradient conditions, the savings for the 1..pi..-km well are estimated as 23 percent of 2.1 million dollars.

Altseimer, J.H.

1976-11-01T23:59:59.000Z

8

Hot Dry Rock; Geothermal Energy  

SciTech Connect

The commercial utilization of geothermal energy forms the basis of the largest renewable energy industry in the world. More than 5000 Mw of electrical power are currently in production from approximately 210 plants and 10 000 Mw thermal are used in direct use processes. The majority of these systems are located in the well defined geothermal generally associated with crustal plate boundaries or hot spots. The essential requirements of high subsurface temperature with huge volumes of exploitable fluids, coupled to environmental and market factors, limit the choice of suitable sites significantly. The Hot Dry Rock (HDR) concept at any depth originally offered a dream of unlimited expansion for the geothermal industry by relaxing the location constraints by drilling deep enough to reach adequate temperatures. Now, after 20 years intensive work by international teams and expenditures of more than $250 million, it is vital to review the position of HDR in relation to the established geothermal industry. The HDR resource is merely a body of rock at elevated temperatures with insufficient fluids in place to enable the heat to be extracted without the need for injection wells. All of the major field experiments in HDR have shown that the natural fracture systems form the heat transfer surfaces and that it is these fractures that must be for geothermal systems producing from naturally fractured formations provide a basis for directing the forthcoming but, equally, they require accepting significant location constraints on HDR for the time being. This paper presents a model HDR system designed for commercial operations in the UK and uses production data from hydrothermal systems in Japan and the USA to demonstrate the reservoir performance requirements for viable operations. It is shown that these characteristics are not likely to be achieved in host rocks without stimulation processes. However, the long term goal of artificial geothermal systems developed by systematic engineering procedures at depth may still be attained if high temperature sites with extensive fracturing are developed or exploited. [DJE -2005

1990-01-01T23:59:59.000Z

9

Simulation of water-rock interaction in the Yellowstone geothermal system using TOUGHREACT  

DOE Green Energy (OSTI)

The Yellowstone geothermal system provides an ideal opportunity to test the ability of reactive transport models to simulate the chemical and hydrological effects of water-rock interaction. Previous studies of the Yellowstone geothermal system have characterized water-rock interaction through analysis of rocks and fluids obtained from both surface and downhole samples. Fluid chemistry, rock mineralogy, permeability, porosity, and thermal data obtained from the Y-8 borehole in Upper Geyser Basin were used to constrain a series of reactive transport simulations of the Yellowstone geothermal system using TOUGHREACT. Three distinct stratigraphic units were encountered in the 153.4 m deep Y-8 drill core: volcaniclastic sandstone, perlitic rhyolitic lava, and nonwelded pumiceous tuff. The main alteration phases identified in the Y-8 core samples include clay minerals, zeolites, silica polymorphs, adularia, and calcite. Temperatures observed in the Y-8 borehole increase with depth from sub-boiling conditions at the surface to a maximum of 169.8 C at a depth of 104.1 m, with near-isothermal conditions persisting down to the well bottom. 1-D models of the Y-8 core hole were constructed to simulate the observed alteration mineral assemblage given the initial rock mineralogy and observed fluid chemistry and temperatures. Preliminary simulations involving the perlitic rhyolitic lava unit are consistent with the observed alteration of rhyolitic glass to form celadonite.

Dobson, Patrick F.; Salah, Sonia; Spycher, Nicolas; Sonnenthal, Eric L.

2003-04-28T23:59:59.000Z

10

Simulation of water-rock interaction in the yellowstone geothermal system using TOUGHREACT  

DOE Green Energy (OSTI)

The Yellowstone geothermal system provides an ideal opportunity to test the ability of reactive transport models to accurately simulate water-rock interaction. Previous studies of the Yellowstone geothermal system have characterized water-rock interaction through analysis of rocks and fluids obtained from both surface and downhole samples. Fluid chemistry, rock mineralogy, permeability, porosity, and thermal data obtained from the Y-8 borehole in Upper Geyser Basin were used to constrain a series of reactive transport simulations of the Yellowstone geothermal system using TOUGHREACT. Three distinct stratigraphic units were encountered in the 153.4 m deep Y-8 drill core: volcaniclastic sandstone, perlitic rhyolitic lava, and nonwelded pumiceous tuff. The main alteration phases identified in the Y-8 core samples include clay minerals, zeolites, silica polymorphs, adularia, and calcite. Temperatures observed in the Y-8 borehole increase with depth from sub-boiling conditions at the surface to a maximum of 169.8 C at a depth of 104.1 m, with near-isothermal conditions persisting down to the well bottom. 1-D models of the Y-8 core hole were constructed to determine if TOUGHREACT could accurately predict the observed alteration mineral assemblage given the initial rock mineralogy and observed fluid chemistry and temperatures. Preliminary simulations involving the perlitic rhyolitic lava unit are consistent with the observed alteration of rhyolitic glass to form celadonite.

Dobson, P.F.; Salah, S.; Spycher, N.; Sonnenthal, E.

2003-04-28T23:59:59.000Z

11

Thermal conductivity of rocks associated with energy extraction from hot dry rock geothermal systems  

DOE Green Energy (OSTI)

Results of thermal conductivity measurements are given for 14 drill core rock samples taken from two exploratory HDR geothermal wellbores (maximum depth of 2929 m (9608 ft) drilled into Precambrian granitic rock in the Jemez Mountains of northern New Mexico. These samples have been petrographically characterized and in general represent fresh competent Precambrian material of deep origin. Thermal conductivities, modal analyses, and densities are given for all core samples studied under dry and water-saturated conditions. Additional measurements are reported for several sedimentary rocks encountered in the upper 760 m (2500 ft) of that same region. A cut-bar thermal conductivity comparator and a transient needle probe were used for the determinations with fused quartz and Pyroceram 9606 as the standards. The maximum temperature range of the measurements was from the ice point to 250/sup 0/C. The measurements on wet, water-saturated rock were limited to the temperature range below room temperature. Conductivity values of the dense core rock samples were generally within the range from 2 to 2.9 W/mK at 200/sup 0/C. Excellent agreement was achieved between these laboratory measurements of thermal conductivity and those obtained by in situ measurements used in the HDR wellbores. By using samples of sufficient thickness to provide a statistically representative heat flow path, no difference between conductivity values and their temperature coefficients for orthogonal directions (heat flow parallel or perpendicular to core axis) was observed. This isotropic behavior was even found for highly foliated gneissic specimens. Estimates of thermal conductivity based on a composite dispersion analysis utilizing pure minerallic phase conductivities and detailed modal analyses usually agreed to within 9 percent of the experimental values.

Sibbitt, W.L.; Dodson, J.G.; Tester, J.W.

1978-01-01T23:59:59.000Z

12

Experimentally determined rock-fluid interactions applicable to a natural hot-dry-rock geothermal system  

DOE Green Energy (OSTI)

The field program cnsists of experiments in which hot rock of low permeability is hydraulically fractured between two wellbores. Water is circulated from one well to the other through the fractured hot rock. Our field experiments are designed to test reservoir engineering parameters such as heat-extraction rates, water-loss rates, flow characteristics including impedance and buoyancy, seismic activity, and fluid chemistry. Laboratory experiments were designed to provide information on the mineral-water reactivity encountered during the field program. Two experimental circulation systems tested the rates of dissolution and alteration during dynamic flow. Solubility of rock in agitated systems was studied. Moreover, pure minerals, samples of the granodiorite from the actual reservoir, and Tijeras Canyon granite have been reacted with distilled water and various solutions of NaCl, NaOH, and Na/sub 2/CO/sub 3/. The results of these experimental systems are compared to the observations made in field experiments done within the hot dry rock reservoir at a depth of approximately 3 km where the initial rock temperature was 150 to 200/sup 0/C.

Charles, R.W.; Grigsby, C.O.; Holley, C.E. Jr.; Tester, J.W.; Blatz, L.A.

1981-01-01T23:59:59.000Z

13

Future of hot dry rock geothermal energy systems  

DOE Green Energy (OSTI)

Where natural groundwater circulation does not exist, the obvious method of extracting heat from the earth's crust is to imitate nature by creating it. A means of doing so by hydraulic fracturing has been demonstrated. Alternatively, explosives or mechanical or chemical methods might be used to open circulation paths. However, where permeabilities are sufficient so that fluid loss is excessive, other approaches are also possible. The magnitude and distribution of hot dry rock and the variety of possible heat-extraction techniques make it appear inevitable that this energy supply will eventually be used on a large scale.

Smith, M.C.

1979-01-01T23:59:59.000Z

14

Rock Mechanics and Enhanced Geothermal Systems: A DOE-sponsored Workshop to Explore Research Needs  

DOE Green Energy (OSTI)

This workshop on rock mechanics and enhanced geothermal systems (EGS) was held in Cambridge, Mass., on June 20-21 2003, before the Soil and Rock America 2003 International Conference at MIT. Its purpose was to bring together experts in the field of rock mechanics and geothermal systems to encourage innovative thinking, explore new ideas, and identify research needs in the areas of rock mechanics and rock engineering applied to enhanced geothermal systems. The agenda is shown in Appendix A. The workshop included experts in the fields of rock mechanics and engineering, geological engineering, geophysics, drilling, the geothermal energy production from industry, universities and government agencies, and laboratories. The list of participants is shown is Appendix B. The first day consisted of formal presentations. These are summarized in Chapter 1 of the report. By the end of the first day, two broad topic areas were defined: reservoir characterization and reservoir performance. Working groups were formed for each topic. They met and reported in plenary on the second day. The working group summaries are described in Chapter 2. The final session of the workshop was devoted to reaching consensus recommendations. These recommendations are given in Chapter 3. That objective was achieved. All the working group recommendations were considered and, in order to arrive at a practical research agenda usable by the workshop sponsors, workshop recommendations were reduced to a total of seven topics. These topics were divided in three priority groups, as follows. First-priority research topics (2): {sm_bullet} Define the pre-existing and time-dependent geometry and physical characteristics of the reservoir and its fracture network. That includes the identification of hydraulically controlling fractures. {sm_bullet} Characterize the physical and chemical processes affecting the reservoir geophysical parameters and influencing the transport properties of fractures. Incorporate those processes in reservoir simulators. Second-priority research topics (4): {sm_bullet} Implement and proof-test enhanced fracture detection geophysical methods, such as 3-D surface seismics, borehole seismics, and imaging using earthquake data. {sm_bullet} Implement and proof-test enhanced stress measurement techniques, such as borehole breakout analysis, tilt-meters, and earthquake focal mechanism analysis. {sm_bullet} Implement and proof-test high-temperature down-hole tools for short-term and long-term diagnostics, such as borehole imaging, geophone arrays, packers, and electrical tools.

Francois Heuze; Peter Smeallie; Derek Elsworth; Joel L. Renner

2003-10-01T23:59:59.000Z

15

Geothermal: Sponsored by OSTI -- CO2-Rock Interactions in EGS...  

Office of Scientific and Technical Information (OSTI)

CO2-Rock Interactions in EGS-CO2: New Zealand TVZ Geothermal Systems as a Natural Analog Geothermal Technologies Legacy Collection HelpFAQ | Site Map | Contact Us | Admin Log On...

16

Numerical studies of fluid-rock interactions in Enhanced Geothermal Systems (EGS) with CO2 as working fluid  

E-Print Network (OSTI)

Development of Enhanced Geothermal Systems, paper presentedin the Deep Reservoir of the Mt. Amiata Geothermal Field,Italy, Transactions, Geothermal Resources Council, 31, 153-

Xu, Tianfu; Pruess, Karsten; Apps, John

2008-01-01T23:59:59.000Z

17

Quartz dissolution and silica deposition in hot-dry-rock geothermal systems  

DOE Green Energy (OSTI)

The kinetics of quartz dissolution control the produced fluid dissolved silica concentration in geothermal systems in which the downhole residence time is finite. The produced fluid of the Phase I, Run Segment 5 experimental Hot Dry Rock (HDR) geothermal system at Fenton Hill, NM, was undersaturated with respect to quartz in one pass through the reservoir, suggesting that the rate of granite dissolution governed the outlet dissolved silica concentration in this system. The literature data for the rate of quartz dissolution in water from 65 to 625/sup 0/C is correlated using an empirical rate law which is first order in quartz surface area and degree of undersaturation of the fluid. The Arrhenius plot (ln k vs T/sup -1/) is linear over eight orders of magnitude of the rate constant, verifying the validity of the proposed rate expression. Carefully performed quartz dissolution experiments in the present study duplicated the literature data and completed the data base in the temperature range from 150 to 250/sup 0/C. Identical experiments using crushed granite indicate that the rate of quartz dissolution in the presence of granite could be as much as 1 to 2 orders of magnitude faster than the rates observed in the pure quartz experiments. A temperature dependent HDR reservoir model incorporates the quartz dissolution rate law to simulate the dissolved silica behavior during the Fenton Hill Run Segment 5 experiment. For this low-permeability, fracture-dominated reservoir, the assumptions of one-dimensional plug flow through a vertically-inclined rectangular fracture and one-dimensional rock heat conduction perpendicular to the direction of flow are employed. These simplifications lead to an analytical solution for the temperature field in the reservoir.

Robinson, B.A.

1982-07-01T23:59:59.000Z

18

Simulation and optimization of hot dry rock geothermal energy conversion systems: process conditions and economics  

DOE Green Energy (OSTI)

The Los Alamos Scientific Laboratory is currently engaged in a field program aimed at designing and testing man-made geothermal reservoirs in hot granitic formations of low permeability created by hydraulic fracturing. A very important segment of the program is concerned with defining and optimizing several parameters related to the performance of the reservoir and their impact on the potential commercial feasibility of the hot dry rock technique. These include effective heat transfer area, permeation water loss, depth to the reservoir, geothermal temperature gradient, reservoir temperature, mass flow rate, and geochemistry. In addition, the optimization of the energy end use system (process or district heating, electricity or cogeneration) is directly linked to reservoir performance and associated costs. This problem has been studied using several computer modeling approaches to identify the sensitivity of the cost of power to reservoir and generation plant parameters. Also examined were a variety of important economic elements including rate of return on invested capital, discount or interest rates, taxes, cash flow, energy selling price, plant and reservoir lifetime, drilling and surface plant costs, and royalties.

Tester, J.W.

1978-01-01T23:59:59.000Z

19

New project for Hot Wet Rock geothermal reservoir design concept  

SciTech Connect

This paper presents the outlines of a new Hot Wet Rock (HWR) geothermal project. The goal of the project is to develop a design methodology for combined artificial and natural crack geothermal reservoir systems with the objective of enhancing the thermal output of existing geothermal power plants. The proposed concept of HWR and the research tasks of the project are described.

Takahashi, Hideaki; Hashida, Toshiyuki

1992-01-01T23:59:59.000Z

20

Isotopic Analysis- Rock At Coso Geothermal Area (1984) | Open Energy  

Open Energy Info (EERE)

Analysis- Rock At Coso Geothermal Area (1984) Analysis- Rock At Coso Geothermal Area (1984) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis- Rock At Coso Geothermal Area (1984) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Isotopic Analysis- Rock Activity Date 1984 Usefulness not indicated DOE-funding Unknown Exploration Basis To analyze evidence for crustal interaction and compositional zonation in the source regions of Pleistocene basaltic and rhyolitic magmas of the Coso volcanic field Notes The isotopic compositions of Pb and Sr in Pleistocene basalt, high-silica rhyolite, and andesitic inclusions in rhyolite of the Coso volcanic field indicate that these rocks were derived from different levels of compositionally zoned magmatic systems. The two earliest rhyolites probably

Note: This page contains sample records for the topic "rock geothermal systems" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Eagle Rock Geothermal Facility | Open Energy Information  

Open Energy Info (EERE)

Eagle Rock Geothermal Facility Eagle Rock Geothermal Facility Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Eagle Rock Geothermal Facility General Information Name Eagle Rock Geothermal Facility Facility Eagle Rock Sector Geothermal energy Location Information Location The Geysers, California Coordinates 38.826770222484°, -122.80002593994° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":38.826770222484,"lon":-122.80002593994,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

22

Lithology and alteration mineralogy of reservoir rocks at Coso Geothermal  

Open Energy Info (EERE)

Lithology and alteration mineralogy of reservoir rocks at Coso Geothermal Lithology and alteration mineralogy of reservoir rocks at Coso Geothermal Area, California Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Lithology and alteration mineralogy of reservoir rocks at Coso Geothermal Area, California Details Activities (1) Areas (1) Regions (0) Abstract: Coso is one of several high-temperature geothermal systems associated with recent volcanic activity in the Basin and Range province. Chemical and fluid inclusion data demonstrate that production is from a narrow, asymmetric plume of thermal water that originates from a deep reservoir to the south and then flows laterally to the north. Geologic controls on the geometry of the upwelling plume were investigated using petrographic and analytical analyses of reservoir rock and vein material.

23

Thermal modeling of the Clear Lake magmatic system, California: Implications for conventional and hot dry rock geothermal development  

Science Conference Proceedings (OSTI)

The combination of recent volcanism, high heat flow ({ge} HFU or 167 mW/m{sup 2}), and high conductive geothermal gradient (up to 120{degree} C/km) makes the Clear Lake region of northern California one of the best prospects for hot dry rock (HDR) geothermal development in the US. The lack of permeability in exploration wells and lack of evidence for widespread geothermal reservoirs north of the Collayomi fault zone are not reassuring indications for conventional geothermal development. This report summarizes results of thermal modeling of the Clear Lake magmatic system, and discusses implications for HDR site selection in the region. The thermal models incorporate a wide range of constraints including the distribution and nature of volcanism in time and space, water and gas geochemistry, well data, and geophysical surveys. The nature of upper crustal magma bodies at Clear Lake is inferred from studying sequences of related silicic lavas, which tell a story of multistage mixing of silicic and mafic magma in clusters of small upper crustal chambers. Thermobarometry on metamorphic xenoliths yield temperature and pressure estimates of {approximately}780--900 C and 4--6 kb respectively, indicating that at least a portion of the deep magma system resided at depths from 14 to 21 km (9 to 12 mi). The results of thermal modeling support previous assessments of the high HDR potential of the area, and suggest the possibility that granitic bodies similar to The Geysers felsite may underlie much of the Clear Lake region at depths as little as 3--6 km. This is significant because future HDR reservoirs could potentially be sited in relatively shallow granitoid plutons rather than in structurally complex Franciscan basement rocks.

Stimac, J.; Goff, F.; Wohletz, K.

1997-06-01T23:59:59.000Z

24

Hot Dry Rock Geothermal Energy Development Program  

DOE Green Energy (OSTI)

During Fiscal Year 1987, emphasis in the Hot Dry Rock Geothermal Energy Development Program was on preparations for a Long-Term Flow Test'' of the Phase II'' or Engineering'' hot dry rock energy system at Fenton Hill, New Mexico. A successful 30-day flow test of the system during FY86 indicated that such a system would produce heat at a temperature and rate that could support operation of a commercial electrical power plant. However, it did not answer certain questions basic to the economics of long-term operation, including the rate of depletion of the thermal reservoir, the rate of water loss from the system, and the possibility of operating problems during extended continuous operation. Preparations for a one-year flow test of the system to answer these and more fundamental questions concerning hot dry rock systems were made in FY87: design of the required surface facilities; procurement and installation of some of their components; development and testing of slimline logging tools for use through small-diameter production tubing; research on temperature-sensitive reactive chemical tracers to monitor thermal depletion of the reservoir; and computer simulations of the 30-day test, extended to modeling the planned Long-Term Flow Test. 45 refs., 34 figs., 5 tabs.

Smith, M.C.; Hendron, R.H.; Murphy, H.D.; Wilson, M.G.

1989-12-01T23:59:59.000Z

25

Single-Well Enhanced Geothermal System Front-End Engineering and Design: Optimization of a Renewable Geothermal System for Harvesting Heat from Hot, Dry Rock  

Science Conference Proceedings (OSTI)

In 2009, GTherm and the Thayer School of Engineering at Dartmouth College, under an EPRI Polaris grant, evaluated the potential for a GTherm single-well enhanced geothermal system (SWEGS) and bottom-hole HeatNest to produce enough heat from deep geothermal wells to be an effective alternative for generating electric power. The research focused on the thermodynamic properties of the SWEGS design and the optimal geologic conditions. The results indicated that, given the right conditions, the SWEGS can extr...

2011-08-12T23:59:59.000Z

26

Numerical studies of fluid-rock interactions in EnhancedGeothermal Systems (EGS) with CO2 as working fluid  

SciTech Connect

There is growing interest in the novel concept of operating Enhanced Geothermal Systems (EGS) with CO{sub 2} instead of water as heat transmission fluid. Initial studies have suggested that CO{sub 2} will achieve larger rates of heat extraction, and can offer geologic storage of carbon as an ancillary benefit. Fluid-rock interactions in EGS operated with CO{sub 2} are expected to be vastly different in zones with an aqueous phase present, as compared to the central reservoir zone with anhydrous supercritical CO{sub 2}. Our numerical simulations of chemically reactive transport show a combination of mineral dissolution and precipitation effects in the peripheral zone of the systems. These could impact reservoir growth and longevity, with important ramifications for sustaining energy recovery, for estimating CO{sub 2} loss rates, and for figuring tradeoffs between power generation and geologic storage of CO{sub 2}.

Xu, Tianfu; Pruess, Karsten; Apps, John

2008-01-17T23:59:59.000Z

27

Capacitive discharge firing system for providing acoustic sources in the hot dry rock geothermal energy development project  

DOE Green Energy (OSTI)

The development of a capacitive discharge firing unit designed to initiate electrically exploded foil slapper detonators in a subsurface, high-pressure (5000 psi), high-temperature (> 200/sup 0/C) environment is described. The unit is used to conduct acoustic ranging experiments in deep boreholes (approx. = 10,000 ft) in the Los Alamos Scientific Laboratory Geothermal Hot Dry Rock experiment.

Patterson, W.W.; Deam, D.R.; MacDonald, H.J.; Rochester, R.H.

1979-07-01T23:59:59.000Z

28

Hot-dry-rock geothermal resource 1980  

DOE Green Energy (OSTI)

The work performed on hot dry rock (HDR) geothermal resource evaluation, site characterization, and geophysical exploration techniques is summarized. The work was done by region (Far West, Pacific Northwest, Southwest, Rocky Mountain States, Midcontinent, and Eastern) and limited to the conterminous US.

Heiken, G.; Goff, F.; Cremer, G. (ed.)

1982-04-01T23:59:59.000Z

29

Rock properties in support of geothermal resource development  

DOE Green Energy (OSTI)

Geothermal rock mechanics needs have been defined and subsequently a test system was designed and built for providing appropriate material properties. The development areas identified as requiring rock mechanics were stimulation, reservoir engineering, subsidence prediction, surface exploration and subsurface evaluation, and drilling. The resulting test system provides mechanical, electrical, thermal and physical properties on 2 and 4 inch diameter cores at confining pressures and pore fluid pressures to 200 MPa (30,000 psi) and temperatures to 535/sup 0/C (1000/sup 0/F). The test system development was continued and site specific rock mechanics requirements were identified. (MHR)

Butters, S.W.

1979-01-01T23:59:59.000Z

30

Hot dry rock geothermal heat extraction  

DOE Green Energy (OSTI)

A man-made geothermal reservoir has been created at a depth of 2.7 km in hot, dry granite by hydraulic fracturing. The system was completed by directionally drilling a second well in close proximity with the top of the vertical fracture. In early 1978 heat was extracted from this reservoir for a period of 75 days. During this period thermal power was produced at an average rate of 4 MW(t). Theoretical analysis of th measured drawdown suggests a total fracture heat transfer area of 16,000 m/sup 2/. Viscous impedance to through-flow declined continuously so that at the end of the experiment this impedance was only one-fifth its initial value. Water losses to the surrounding rock formation also decreased continuously, and eventually this loss rate was less than 1% of the circulated flow rate. Geochemical analyses suggest that, with scale up of the heat transfer area and deeper, hotter reservoirs, hot dry rock reservoirs can ultimately produce levels of power on a commercial scale.

Murphy, H.D.

1979-01-01T23:59:59.000Z

31

Decision Analysis for Enhanced Geothermal Systems Geothermal...  

Open Energy Info (EERE)

Recovery Act: Enhanced Geothermal Systems Component Research and DevelopmentAnalysis Project Type Topic 2 Geothermal Analysis Project Description The result of the proposed...

32

Geothermal: Sponsored by OSTI -- Engineered Geothermal Systems...  

Office of Scientific and Technical Information (OSTI)

Engineered Geothermal Systems Energy Return On Energy Investment Geothermal Technologies Legacy Collection HelpFAQ | Site Map | Contact Us | Admin Log On HomeBasic Search About...

33

Enhanced Geothermal Systems  

DOE Green Energy (OSTI)

Geothermal energy is recovered by circulating water through heat exchange areas within a hot rock mass. Geothermal reservoir rock masses generally consist of igneous and metamorphic rocks that have low matrix permeability. Therefore, cracks and fractures play a significant role in extraction of geothermal energy by providing the major pathways for fluid flow and heat exchange. Therefore, knowledge of the conditions leading to formation of fractures and fracture networks is of paramount importance. Furthermore, in the absence of natural fractures or adequate connectivity, artificial fractures are created in the reservoir using hydraulic fracturing. Multiple fractures are preferred because of the large size necessary when using only a single fracture. Although the basic idea is rather simple, hydraulic fracturing is a complex process involving interactions of high pressure fluid injections with a stressed hot rock mass, mechanical interaction of induced fractures with existing natural fractures, and the spatial and temporal variations of in-situ stress. As a result, it is necessary to develop tools that can be used to study these interactions as an integral part of a comprehensive approach to geothermal reservoir development, particularly enhanced geothermal systems. In response to this need we have developed advanced poro-thermo-chemo-mechanical fracture models for rock fracture research in support of EGS design. The fracture propagation models are based on a regular displacement discontinuity formulation. The fracture propagation studies include modeling interaction of induced fractures. In addition to the fracture propagation studies, two-dimensional solution algorithms have been developed and used to estimate the impact of pro-thermo-chemical processes on fracture permeability and reservoir pressure. Fracture permeability variation is studied using a coupled thermo-chemical model with quartz reaction kinetics. The model is applied to study quartz precipitation/dissolution, as well as the variation in fracture aperture and pressure. Also, a three-dimensional model of injection/extraction has been developed to consider the impact poro- and thermoelastic stresses on fracture slip and injection pressure. These investigations shed light on the processes involved in the observed phenomenon of injection pressure variation (e.g., in Coso), and allow the assessment of the potential of thermal and chemical stimulation strategies.

Ahmad Ghassemi

2009-10-01T23:59:59.000Z

34

Los Alamos hot dry rock geothermal energy experiment  

DOE Green Energy (OSTI)

Recent heat flow data indicates that about 95,000 sq. mi. in 13 western U.S. states is underlain, at a depth of 5 km (16,400 ft) by hot dry rock at temperatures above 290/sup 0/C (440/sup 0/F.). Therefore a geothermal energy development program was undertaken to develop methods from extracting thermal energy from hot rock in the earth crust by man-made underground circulation systems; demonstrate the commercial feasibility of such systems; and encourage use of this technology. Experiments performed on the Jemez Plateau in New Mexico are described with information on the drilling of boreholes, hydraulic fracturing of hot rocks, well logging, and environmental monitoring to establish base line data and define the potential effects of the project. The technical achievements of the project include boreholes were drilled to 3k (10,000 ft) with bottomhole temperatures of approximately 200/sup 0/C (390/sup 0/F); hydraulic fracturing produced fractured regions with 150 m (500 ft) radii; at least 90 percent of the water injected was recovered; and data was obtained on geologic conditions, seismic effects, and thermal, fracturing, and chemical properties of the downhole rocks. A geothermal power-production system model was formulated for evaluating the total cost of developing power production using a hot-dry-rock geothermal energy source. (LCL)

Pettitt, R.A.

1976-01-01T23:59:59.000Z

35

Artificial geothermal reservoirs in hot volcanic rock  

SciTech Connect

S>Some recent results from the Los Alamos program in which hydraulic fracturing is used for the recovery of geothermal energy are discussed. The location is about 4 kilometers west and south of the ring fault of the enormous Jemez Caldera in the northcentral part of New Mexico. It is shown that geothermal energy may be extracted from hot rock that does not contain circulating hot water or steam and is relatively impermeable. A fluid is pumped at high pressure into an isolated section of a wellbore. If the well is cased the pipe in this pressurized region is perforated as it is in the petroleum industry, so that the pressure may be applied to the rock, cracking it. A second well is drilled a few hundred feet away from the first. Cold water is injected through the first pipe, circulates through the crack, and hot water returns to the surface through the second pipe. Results are described and circumstances are discussed under which artiflcial geothermal reservoirs might be created in the basaltic rock of Hawaii. (MCW)

Aamodt, R.L.

1974-02-08T23:59:59.000Z

36

Enhanced Geothermal Systems (EGS) R&D Program, Status Report: Foreign Research on Enhanced Geothermal Systems  

DOE Green Energy (OSTI)

This report reviews enhanced geothermal systems (EGS) research outside the United States. The term ''enhanced geothermal systems'' refers to the use of advanced technology to extract heat energy from underground in areas with higher than average heat flow but where the natural permeability or fluid content is limited. EGS covers the spectrum of geothermal resources from low permeability hydrothermal to hot dry rock.

McLarty, Lynn; Entingh, Daniel

2000-09-29T23:59:59.000Z

37

Hot Dry Rock Geothermal Energy Development Program  

DOE Green Energy (OSTI)

The overall objective of the Hot Dry Rock (HDR) Geothermal Energy Development Program is to determine the technical and economic feasibility of HDR as a significant energy source and to provide a basis for its timely commercial development. Principal operational tasks are those activities required to enable a decision to be made by FY86 on the ultimate commercialization of HDR. These include development and analyis of a 20- to 50-MW Phase II HDR reservoir at Site 1 (Fenton Hill) with the potential construction of a pilot electric generating station, Phase III; selection of a second site with subsequent reservoir development and possible construction of a direct heat utilization pilot plant of at least 30 MW thermal thereon; the determination of the overall domestic HDR energy potential; and the evaluation of 10 or more target prospect areas for future HDR plant development by commercial developers. Phase I of the Los Alamos Scientific Laboratory's Fenton Hill project was completed. Phase I evaluated a small subterranean system comprised of two boreholes connected at a depth of 3 km by hydraulic fracturing. A closed-loop surface system has been constructed and tests involving round-the-clock operation have yielded promising data on heat extraction, geofluid chemistry, flow impedance, and loss of water through the underground reservoir between the two holes, leading to cautions optimism for the future prospects of private-sector HDR power plants. (MHR)

Franke, P.R.

1979-01-01T23:59:59.000Z

38

Induced seismicity associated with enhanced geothermal system  

E-Print Network (OSTI)

Cooper Basin, Australia. Geothermal Resources Council Trans.a hot fractured rock geothermal project. Engineering Geologyseismicity in The Geysers geothermal area, California. J.

Majer, Ernest L.

2006-01-01T23:59:59.000Z

39

Industrial applications of hot dry rock geothermal energy  

DOE Green Energy (OSTI)

Geothermal resources in the form of naturally occurring hot water or steam have been utilized for many years. While these hydrothermal resources are found in many places, the general case is that the rock at depth is hot, but does not contain significant amounts of mobile fluid. An extremely large amount of geothermal energy is found around the world in this hot dry rock (HDR). Technology has been under development for more than twenty years at the Los Alamos National Laboratory in the United States and elsewhere to develop the technology to extract the geothermal energy from HDR in a form useful for electricity generation, space heating, or industrial processing. HDR technology is especially attractive for industrial applications because of the ubiquitous distribution of the HDR resource and the unique aspects of the process developed to recover it. In the HDR process, as developed at Los Alamos, water is pumped down a well under high pressure to open up natural joints in hot rock and create an artificial geothermal reservoir. Energy is extracted by circulating water through the reservoir. Pressurized hot water is returned to the surface through the production well, and its thermal energy is extracted for practical use. The same water is then recirculated through the system to mine more geothermal heat. Construction of a pilot HDR facility at Fenton Hill, NM, USA, has recently been completed by the Los Alamos National Laboratory. It consists of a large underground reservoir, a surface plant, and the connecting wellbores. This paper describes HDR technology and the current status of the development program. Novel industrial applications of geothermal energy based on the unique characteristics of the HDR energy extraction process are discussed.

Duchane, D.V.

1992-09-01T23:59:59.000Z

40

Industrial applications of hot dry rock geothermal energy  

DOE Green Energy (OSTI)

Geothermal resources in the form of naturally occurring hot water or steam have been utilized for many years. While these hydrothermal resources are found in many places, the general case is that the rock at depth is hot, but does not contain significant amounts of mobile fluid. An extremely large amount of geothermal energy is found around the world in this hot dry rock (HDR). Technology has been under development for more than twenty years at the Los Alamos National Laboratory in the United States and elsewhere to develop the technology to extract the geothermal energy from HDR in a form useful for electricity generation, space heating, or industrial processing. HDR technology is especially attractive for industrial applications because of the ubiquitous distribution of the HDR resource and the unique aspects of the process developed to recover it. In the HDR process, as developed at Los Alamos, water is pumped down a well under high pressure to open up natural joints in hot rock and create an artificial geothermal reservoir. Energy is extracted by circulating water through the reservoir. Pressurized hot water is returned to the surface through the production well, and its thermal energy is extracted for practical use. The same water is then recirculated through the system to mine more geothermal heat. Construction of a pilot HDR facility at Fenton Hill, NM, USA, has recently been completed by the Los Alamos National Laboratory. It consists of a large underground reservoir, a surface plant, and the connecting wellbores. This paper describes HDR technology and the current status of the development program. Novel industrial applications of geothermal energy based on the unique characteristics of the HDR energy extraction process are discussed.

Duchane, D.V.

1992-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rock geothermal systems" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Hot Dry Rock Geothermal Reservoir Model Development at Los Alamos  

DOE Green Energy (OSTI)

Discrete fracture and continuum models are being developed to simulate Hot Dry Rock (HDR) geothermal reservoirs. The discrete fracture model is a two-dimensional steady state simulator of fluid flow and tracer transport in a fracture network which is generated from assumed statistical properties of the fractures. The model's strength lies in its ability to compute the steady state pressure drop and tracer response in a realistic network of interconnected fractures. The continuum approach models fracture behavior by treating permeability and porosity as functions of temperature and effective stress. With this model it is practical to model transient behavior as well as the coupled processes of fluid flow, heat transfer, and stress effects in a three-dimensional system. The model capabilities being developed will also have applications in conventional geothermal systems undergoing reinjection and in fractured geothermal reservoirs in general.

Robinson, Bruce A.; Birdsell, Stephen A.

1989-03-21T23:59:59.000Z

42

Hot Dry Rock geothermal reservoir model development at Los Alamos  

DOE Green Energy (OSTI)

Discrete fracture and continuum models are being developed to simulate Hot Dry Rock (HDR) geothermal reservoirs. The discrete fracture model is a two-dimensional steady state simulator of fluid flow and tracer transport in a fracture network which is generated from assumed statistical properties of the fractures. The model's strength lies in its ability to compute the steady state pressure drop and tracer response in a realistic network of interconnected fractures. The continuum approach models fracture behavior by treating permeability and porosity as functions of temperature and effective stress. With this model it is practical to model transient behavior as well as the coupled processes of fluid flow, heat transfer, and stress effects in a three-dimensional system. The model capabilities being developed will also have applications in conventional geothermal systems undergoing reinjection and in fractured geothermal reservoirs in general. 15 refs., 7 figs.

Robinson, B.A.; Birdsell, S.A.

1989-01-01T23:59:59.000Z

43

Seismic Technology Adapted to Analyzing and Developing Geothermal Systems Below Surface-Exposed High-Velocity Rocks Final Report  

Science Conference Proceedings (OSTI)

The objective of our research was to develop and demonstrate seismic data-acquisition and data-processing technologies that allow geothermal prospects below high-velocity rock outcrops to be evaluated. To do this, we acquired a 3-component seismic test line across an area of exposed high-velocity rocks in Brewster County, Texas, where there is high heat flow and surface conditions mimic those found at numerous geothermal prospects. Seismic contractors have not succeeded in creating good-quality seismic data in this area for companies who have acquired data for oil and gas exploitation purposes. Our test profile traversed an area where high-velocity rocks and low-velocity sediment were exposed on the surface in alternating patterns that repeated along the test line. We verified that these surface conditions cause non-ending reverberations of Love waves, Rayleigh waves, and shallow critical refractions to travel across the earth surface between the boundaries of the fast-velocity and slow-velocity material exposed on the surface. These reverberating surface waves form the high level of noise in this area that does not allow reflections from deep interfaces to be seen and utilized. Our data-acquisition method of deploying a box array of closely spaced geophones allowed us to recognize and evaluate these surface-wave noise modes regardless of the azimuth direction to the surface anomaly that backscattered the waves and caused them to return to the test-line profile. With this knowledge of the surface-wave noise, we were able to process these test-line data to create P-P and SH-SH images that were superior to those produced by a skilled seismic data-processing contractor. Compared to the P-P data acquired along the test line, the SH-SH data provided a better detection of faults and could be used to trace these faults upward to the boundaries of exposed surface rocks. We expanded our comparison of the relative value of S-wave and P-wave seismic data for geothermal applications by inserting into this report a small part of the interpretation we have done with 3C3D data across Wister geothermal field in the Imperial Valley of California. This interpretation shows that P-SV data reveal faults (and by inference, also fractures) that cannot be easily, or confidently, seen with P-P data, and that the combination of P-P and P-SV data allows VP/VS velocity ratios to be estimated across a targeted reservoir interval to show where an interval has more sandstone (the preferred reservoir facies). The conclusion reached from this investigation is that S-wave seismic technology can be invaluable to geothermal operators. Thus we developed a strong interest in understanding the direct-S modes produced by vertical-force sources, particularly vertical vibrators, because if it can be demonstrated that direct-S modes produced by vertical-force sources can be used as effectively as the direct-S modes produced by horizontal-force sources, geothermal operators can acquire direct-S data across many more prospect areas than can be done with horizontal-force sources, which presently are limited to horizontal vibrators. We include some of our preliminary work in evaluating direct-S modes produced by vertical-force sources.

Hardage, Bob A; DeAngelo, Michael V; Ermolaeva, Elena; Hardage, Bob A; Remington, Randy; Sava, Diana; Wagner, Donald; Wei, Shuijion

2013-02-28T23:59:59.000Z

44

Los Alamos hot dry rock geothermal project  

DOE Green Energy (OSTI)

The greatest potential for geothermal energy is the almost unlimited energy contained in the vast regions of hot, but essentially impermeable, rock within the first six or seven km of the Earth's crust. For the past five years, the Los Alamos Scientific Laboratory has been investigating and developing a practical, economical and environmentally acceptable method of extracting this energy. By early 1978, a 10 MW (thermal) heat extraction experiment will be in operation. In the Los Alamos concept, a man-made geothermal reservoir is formed by drilling into a region of suitably hot rock, and then creating within the rock a very large surface for heat transfer by large-scale hydraulic-fracturing techniques. After a circulation loop is formed by drilling a second hole to intersect the fractured region, the heat contained in this reservoir is brought to the surface by the buoyant closed-loop circulation of water. The water is kept liquid throughout the loop by pressurization, thereby increasing the rate of heat transport up the withdrawal hole compared to that possible with steam.

Brown, D.W.; Pettitt, R.A.

1977-01-01T23:59:59.000Z

45

Hot Dry Rock Geothermal Energy In The Jemez Volcanic Field, New Mexico |  

Open Energy Info (EERE)

Rock Geothermal Energy In The Jemez Volcanic Field, New Mexico Rock Geothermal Energy In The Jemez Volcanic Field, New Mexico Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Hot Dry Rock Geothermal Energy In The Jemez Volcanic Field, New Mexico Details Activities (2) Areas (1) Regions (0) Abstract: Large, young calderas possess immense geothermal potential due to the size of shallow magma bodies that underlie them. Through the example of the Valles and Toledo calderas, New Mexico, and older, more deeply eroded and exposed calderas, it is possible to reconstruct a general view of geothermal environments associated with such magmatic systems. Although a zone of anomalous heat flow extends well beyond caldera margins, high- to moderate-temperature hydrothermal systems appear to be restricted to zones

46

Recent developments in the hot dry rock geothermal energy program  

DOE Green Energy (OSTI)

In recent years, most of the Hot Dry Rock Programs effort has been focused on the extraction technology development effort at the Fenton Hill test site. The pair of approximately 4000 m wells for the Phase II Engineering System of the Fenton Hill Project have been completed. During the past two years, hydraulic fracture operations have been carried out to develop the geothermal reservoir. Impressive advances have been made in fracture identification techniques and instrumentation. To develop a satisfactory interwellbore flow connection the next step is to redrill the lower section of one of the wells into the fractured region. Chemically reactive tracer techniques are being developed to determine the effective size of the reservoir area. A new estimate has been made of the US hot dry rock resource, based upon the latest geothermal gradiant data. 3 figs.

Franke, P.R.; Nunz, G.J.

1985-01-01T23:59:59.000Z

47

Isotopic Analysis- Rock At Coso Geothermal Area (1997) | Open Energy  

Open Energy Info (EERE)

Rock At Coso Geothermal Area (1997) Rock At Coso Geothermal Area (1997) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis- Rock At Coso Geothermal Area (1997) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Isotopic Analysis- Rock Activity Date 1997 Usefulness useful DOE-funding Unknown Exploration Basis Determine a major lithospheric boundary Notes Sr and Nd isotope ratios of Miocene-Recent basalts in eastern California, when screened for crustal contamination, vary dramatically and indicate the presence of a major lithospheric boundary that is not obvious from surface geology. Isotope ratios from the Coso field form a bull's-eye pattern with very low 87Sr/86Sr (0.7033) centered just south of the geothermal area. The

48

Rock Sampling At Coso Geothermal Area (1995) | Open Energy Information  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Rock Sampling At Coso Geothermal Area (1995) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Rock Sampling At Coso Geothermal Area (1995) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Rock Sampling Activity Date 1995 Usefulness not indicated DOE-funding Unknown Notes Geologic controls on the geometry of the upwelling plume were investigated using petrographic and analytical analyses of reservoir rock and vein material. References Lutz, S.J.; Moore, J.N. ; Copp, J.F. (1 June 1995) Lithology and alteration mineralogy of reservoir rocks at Coso Geothermal Area,

49

Borehole temperature survey analysis hot dry rock geothermal reservoir  

DOE Green Energy (OSTI)

The Los Alamos Scientific Laboratory (LASL) has been actively investigating the potential for extracting geothermal energy from hot dry rock. A man-made geothermal reservoir has been formed at the Fenton Hill Test Site in northern New Mexico. The 10-MW (thermal) prototype energy extraction circulation loop has been completed and has been continuously operating since January 28 of this year. The performance of the Phase I 1000-h circulation experiment would establish technological assessment of the particular hot dry rock geothermal reservoir. The major parameters of interest include equipment operations, geochemistry, water loss, and reservoir thermal drawdown. Temperature measurements were used extensively as one method to study the man-made geothermal reservoir. The temperature probe is one of the less complex wellbore survey tools that is readily fielded to allow on-line analysis of changing conditions in the hydraulic-fracture system. Several downhole temperature instruments have been designed and fabricated for use in the GT-2/EE-1 wellbores.

Dennis, B.R.; Murphy, H.D.

1978-01-01T23:59:59.000Z

50

A Phase-Partitioning Model for CO2Brine Mixtures at Elevated Temperatures and Pressures: Application to CO2-Enhanced Geothermal Systems  

E-Print Network (OSTI)

D.W. : A hot dry rock geothermal energy concept utilizingtwenty-?fth workshop on geothermal reservoir engineering,the development of enhanced geothermal systems? In: Paper

Spycher, Nicolas; Pruess, Karsten

2010-01-01T23:59:59.000Z

51

Alternate operating strategies for Hot Dry Rock geothermal reservoirs  

DOE Green Energy (OSTI)

Flow testing and heat extraction experiments in prototype Hot Dry Rock (HDR) geothermal reservoirs have uncovered several challenges which must be addressed before commercialization of the technology is possible. Foremost among these is the creation of a reservoir which simultaneously possesses high permeability pathways and a large volume of fractured rock. The current concept of heat extraction -- a steady state circulation system with fluid pumping from the injection well to a single, low pressure production well -- may limit our ability to create heat extraction systems which meet these goals. A single injection well feeding two production wells producing fluid at moderate pressures is shown to be a potentially superior way to extract heat. Cyclic production is also demonstrated to have potential as a method for sweeping fluid through a larger volume of rock, thereby inhibiting flow channeling and increasing reservoir lifetime. 10 refs., 4 figs., 2 tabs.

Robinson, B.A.

1991-01-01T23:59:59.000Z

52

Microfractures in rocks from two geothermal areas | Open Energy Information  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Microfractures in rocks from two geothermal areas Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Microfractures in rocks from two geothermal areas Details Activities (2) Areas (2) Regions (0) Abstract: Core samples from the Dunes, California, and Raft River, Idaho, geothermal areas show diagenesis superimposed on episodic fracturing and fracture sealing. The minerals that fill fractures show significant temporal variations. Sealed fractures can act as barriers to fluid flow. Sealed fractures often mark boundaries between regions of significantly

53

National Geothermal Data System (NGDS) Geothermal Data Domain...  

Open Energy Info (EERE)

National Geothermal Data System (NGDS) Geothermal Data Domain: Assessment of Geothermal Community Data Needs Jump to: navigation, search OpenEI Reference LibraryAdd to library...

54

Coincident P and Sh reflections from basement rocks at Coso geothermal  

Open Energy Info (EERE)

Coincident P and Sh reflections from basement rocks at Coso geothermal Coincident P and Sh reflections from basement rocks at Coso geothermal field Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Coincident P and Sh reflections from basement rocks at Coso geothermal field Details Activities (2) Areas (1) Regions (0) Abstract: In mid-1989 the authors designed and collected four seismic reflection/refraction profiles that addressed the crustal structure of the Coso geothermal field. The two main east-west and north-south profiles crossed at the southeasternmost base of Sugar Loaf Mountain. Both in-line and cross-line Vibroseis and explosion data were recorded on each of these approximately 12-mi lines. This was accomplished with the simultaneous operation of two 1024-channel sign bit recording systems while four

55

Hybrid Geothermal Heat Pump Systems  

Science Conference Proceedings (OSTI)

Hybrid geothermal heat pump systems offer many of the benefits of full geothermal systems but at lower installed costs. A hybrid geothermal system combines elements of a conventional water loop heat pump system in order to reduce the geothermal loop heat exchanger costs, which are probably the largest cost element of a geothermal system. These hybrid systems have been used successfully where sufficient ground space to install large heat exchangers for full geothermal options was unavailable, or where the...

2009-12-21T23:59:59.000Z

56

Sedimentary Geothermal Systems | Open Energy Information  

Open Energy Info (EERE)

Sedimentary Geothermal Systems Sedimentary Geothermal Systems Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Print PDF Geopressured Geothermal Systems Geothermal Technologies There are many types of Geothermal Technologies that take advantage of the earth's heat: Hydrothermal Systems Enhanced Geothermal Systems (EGS) Sedimentary Geothermal Systems Co-Produced Geothermal Systems Geothermal Direct Use Ground Source Heat Pumps Sedimentary Geothermal Links Related documents and websites Estimate of the Geothermal Energy Resource in the Major Sedimentary Basins in the United States Recoverable Resource Estimate of Identified Onshore Geopressured Geothermal Energy in Texas and Louisiana EGS Schematic.jpg ] Dictionary.png Sedimentary Geothermal Systems: Sedimentary Geothermal Systems produce electricity from medium temperature,

57

Modeling of geothermal systems  

DOE Green Energy (OSTI)

During the last decade the use of numerical modeling for geothermal resource evaluation has grown significantly, and new modeling approaches have been developed. In this paper we present a summary of the present status in numerical modeling of geothermal systems, emphasizing recent developments. Different modeling approaches are described and their applicability discussed. The various modeling tasks, including natural-state, exploitation, injection, multi-component and subsidence modeling, are illustrated with geothermal field examples. 99 refs., 14 figs.

Bodvarsson, G.S.; Pruess, K.; Lippmann, M.J.

1985-03-01T23:59:59.000Z

58

Residential Geothermal Systems Credit  

Energy.gov (U.S. Department of Energy (DOE))

A resident individual taxpayer of Montana who installs a geothermal heating or cooling system in their principal dwelling can claim a tax credit based on the installation costs of the system, not...

59

Black Rock III Geothermal Project | Open Energy Information  

Open Energy Info (EERE)

Black Rock III Geothermal Project Black Rock III Geothermal Project Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Development Project: Black Rock III Geothermal Project Project Location Information Coordinates The following coordinate was not recognized: 33°19'59" N, 115°50'3 W.The following coordinate was not recognized: 33°19'59" N, 115°50'3 W. Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[]}

60

Neutron imaging for geothermal energy systems  

Science Conference Proceedings (OSTI)

Geothermal systems extract heat energy from the interior of the earth using a working fluid, typically water. Three components are required for a commercially viable geothermal system: heat, fluid, and permeability. Current commercial electricity production using geothermal energy occurs where the three main components exist naturally. These are called hydrothermal systems. In the US, there is an estimated 30 GW of base load electrical power potential for hydrothermal sites. Next generation geothermal systems, named Enhanced Geothermal Systems (EGS), have an estimated potential of 4500 GW. EGSs lack in-situ fluid, permeability or both. As such, the heat exchange system must be developed or engineered within the rock. The envisioned method for producing permeability in the EGS reservoir is hydraulic fracturing, which is rarely practiced in the geothermal industry, and not well understood for the rocks typically present in geothermal reservoirs. High costs associated with trial and error learning in the field have led to an effort to characterize fluid flow and fracturing mechanisms in the laboratory to better understand how to design and manage EGS reservoirs. Neutron radiography has been investigated for potential use in this characterization. An environmental chamber has been developed that is suitable for reproduction of EGS pressures and temperatures and has been tested for both flow and precipitations studies with success for air/liquid interface imaging and 3D reconstruction of precipitation within the core.

Bingham, Philip R [ORNL; Anovitz, Lawrence {Larry} M [ORNL; Polsky, Yarom [ORNL

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rock geothermal systems" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Enhanced Geothermal Systems (EGS) | Open Energy Information  

Open Energy Info (EERE)

Enhanced Geothermal Systems (EGS) Enhanced Geothermal Systems (EGS) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Print PDF Enhanced Geothermal Systems (EGS) Geothermal Technologies There are many types of Geothermal Technologies that take advantage of the earth's heat: Hydrothermal Systems Enhanced Geothermal Systems (EGS) Sedimentary Geothermal Systems Co-Produced Geothermal Systems Geothermal Direct Use Ground Source Heat Pumps EGS Links Related documents and websites DOE EGS Technical Roadmap DOE EGS Systems Demonstration Projects How EGS Works (Animation) EGS Development (Animation) EGS Schematic.jpg ] Dictionary.png Enhanced Geothermal Systems: Enhanced Geothermal Systems (EGS) are human engineered hydrothermal reservoirs developed for commercial use as an alternative to naturally

62

Geothermal systems of northern Nevada  

DOE Green Energy (OSTI)

Hot springs are numerous and nearly uniformly distributed in northern Nevada. Most occur on the flanks of basins, along Basin and Range (late Miocene to Holocene) faults, while some occur in the inner parts of the basins. Surface temperatures of the springs range from slightly above ambient to boiling; some springs are superheated. Maximum subsurface water temperatures calculated on the basis of quartz solubility range as high as 252/sup 0/C, although most are below 190/sup 0/C. Flows range from a trickle to several hundred liters per minute. The Nevada geothermal systems differ markedly from the power-producing system at The Geysers, Calif., and from those areas with a high potential for power production (e.g., Yellowstone Park, Wyo.; Jemez Mountains, N. Mex.). These other systems are associated with Quaternary felsic volcanic rocks and probably derive their heat from cooling magma rather high in the crust. In northern Nevada, however, felsic volcanic rocks are virtually all older than 10 million years, and analogous magmatic heat sources are, therefore, probably lacking. Nevada is part of an area of much higher average heat flow than the rest of the United States. In north-central Nevada, geothermal gradients are as great as 64/sup 0/C per kilometer in bedrock and even higher in basin fill. The high gradients probably result from a combination of thin crust and high temperature upper mantle. It is suggested that the geothermal systems of northern Nevada result from circulation of meteoric waters along Basin and Range faults and that their temperature chiefly depends upon (1) depth of circulation and (2) the geothermal gradient near the faults.

Hose, R.K.; Taylor, B.E.

1974-01-01T23:59:59.000Z

63

Geothermal Technologies Program: Enhanced Geothermal Systems  

DOE Green Energy (OSTI)

This general publication describes enhanced geothermal systems (EGS) and the principles of operation. It also describes the DOE program R&D efforts in this area, and summarizes several projects using EGS technology.

Not Available

2004-08-01T23:59:59.000Z

64

National Geothermal Data System (NGDS) Geothermal Data Domain: Assessment  

Open Energy Info (EERE)

National Geothermal Data System (NGDS) Geothermal Data Domain: Assessment National Geothermal Data System (NGDS) Geothermal Data Domain: Assessment of Geothermal Community Data Needs Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Paper: National Geothermal Data System (NGDS) Geothermal Data Domain: Assessment of Geothermal Community Data Needs Abstract To satisfy the critical need for geothermal data to advance geothermal energy as a viable renewable energy contender, the U.S. Department of Energy is in-vesting in the development of the National Geothermal Data System (NGDS). This paper outlines efforts among geothermal data providers nationwide to sup-ply cutting edge geoinformatics. NGDS geothermal data acquisition, delivery, and methodology are dis-cussed. In particular, this paper addresses the various types of data required to effectively assess

65

American Geothermal Systems | Open Energy Information  

Open Energy Info (EERE)

navigation, search Name American Geothermal Systems Place Austin, Texas Sector Geothermal energy Product Installer of geothermal heating and cooling technologies, also has a...

66

BOREHOLE PRECONDITIONING OF GEOTHERMAL WELLS FOR ENHANCED GEOTHERMAL SYSTEM  

Open Energy Info (EERE)

BOREHOLE PRECONDITIONING OF GEOTHERMAL WELLS FOR ENHANCED GEOTHERMAL SYSTEM BOREHOLE PRECONDITIONING OF GEOTHERMAL WELLS FOR ENHANCED GEOTHERMAL SYSTEM RESERVOIR DEVELOPMENT Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: BOREHOLE PRECONDITIONING OF GEOTHERMAL WELLS FOR ENHANCED GEOTHERMAL SYSTEM RESERVOIR DEVELOPMENT Details Activities (1) Areas (1) Regions (0) Abstract: Thermal stimulation can be utilized to precondition a well to optimize fracturing and production during Enhanced Geothermal System (EGS) reservoir development. A finite element model was developed for the fully coupled processes consisting of: thermoporoelastic deformation, hydraulic conduction, thermal osmosis, heat conduction, pressure thermal effect, and the interconvertibility of mechanical and thermal energy. The model has

67

Geothermal: Sponsored by OSTI -- Enhanced Geothermal System Potential...  

Office of Scientific and Technical Information (OSTI)

Enhanced Geothermal System Potential for Sites on the Eastern Snake River Plain, Idaho Geothermal Technologies Legacy Collection HelpFAQ | Site Map | Contact Us | Admin Log On...

68

Economic predictions for heat mining : a review and analysis of hot dry rock (HDR) geothermal energy technology  

E-Print Network (OSTI)

The main objectives of this study were first, to review and analyze several economic assessments of Hot Dry Rock (HDR) geothermal energy systems, and second, to reformulate an economic model for HDR with revised cost components.

Tester, Jefferson W.

1990-01-01T23:59:59.000Z

69

Black Rock Point Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

Black Rock Point Geothermal Area Black Rock Point Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermal Resource Area: Black Rock Point Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory and Environmental Issues 4 Exploration History 5 Well Field Description 6 Geology of the Area 7 Geofluid Geochemistry 8 NEPA-Related Analyses (0) 9 Exploration Activities (0) 10 References Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"TERRAIN","zoom":6,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"500px","height":"300px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":40.9553,"lon":-119.1141,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

70

Issues facing the developmt of hot dry rock geothermal resources  

DOE Green Energy (OSTI)

Technical and economic issues related to the commercial feasibility of hot dry rock geothermal energy for producing electricity and heat will be discussed. Topics covered will include resource characteristics, reservoir thermal capacity and lifetime, drilling and surface plant costs, financial risk and anticipated rate of return.

Tester, J.W.

1979-01-01T23:59:59.000Z

71

The hot dry rock geothermal energy program  

DOE Green Energy (OSTI)

The paper presents a simplified description of the Department of Energy's Hot-Dry-Rock program conducted at Fenton Hill, New Mexico. What a hot-dry-rock resource is and what the magnitude of the resource is are also described.

Smith, M.C.

1987-09-01T23:59:59.000Z

72

Proceedings of hot dry rock geothermal workshop  

DOE Green Energy (OSTI)

Abstracts of 38 papers are included on the following subjects: rock mechanics, part 1: hydraulic fracturing; fracture imaging and borehole surveying; fluid flow-pressure analyses; rock mechanics, part 2: hydraulic fracturing and thermal cracking; geochemistry; heat extraction modeling; and economics and energy conversion. (MHR)

Elsner, D.B. (comp.)

1978-09-01T23:59:59.000Z

73

Electricity from hot dry rock geothermal energy: technical and economic issues  

SciTech Connect

Extraction of energy from hot dry rock would make available a nearly unlimited energy source. Some of the technical problems and possible economic tradeoffs involved in a power generating system are examined and possible solutions proposed. An intertemporal optimization computer model of electricity production from a hot dry rock geothermal source has been constructed. The effects of reservoir degradation, variable fluid flow rate, and drilling operations are examined to deetermine optimal strategies for reservoir management and necessary conditions for economic feasibility.

Tester, J.W.; Morris, G.E.; Cummings, R.G.; Bivins, R.L.

1979-01-01T23:59:59.000Z

74

Geothermal Technologies Office: Enhanced Geothermal Systems Technologi...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

and Renewable Energy EERE Home | Programs & Offices | Consumer Information Geothermal Technologies Office Search Search Help Geothermal Technologies Office HOME ABOUT...

75

Geothermal Technologies Office: Enhanced Geothermal Systems  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

and Renewable Energy EERE Home | Programs & Offices | Consumer Information Geothermal Technologies Office Search Search Help Geothermal Technologies Office HOME ABOUT...

76

Chemistry and materials in geothermal systems  

DOE Green Energy (OSTI)

The development of a geothermal fluid, from its origin as meteoric water precipitating on the earth's surface, as it flows through the soils and rocks of geological formations, to the point where it returns to the surface as a hot spring, geyser, well, etc. is traced. Water of magmatic origin is also included. The tendency of these hydrothermal fluids to form scales by precipitation of a portion of their dissolved solids is noted. A discussion is presented of types of information required for materials selection for energy systems utilizing geothermal fluids, including pH, temperature, the speciation of the particular geothermal fluid (particularly chloride, sulfide and carbon dioxide content) and various types of corrosive attack on common materials. Specific examplers of materials response to geothermal fluid are given.

Miller, R.L.

1979-05-01T23:59:59.000Z

77

OIT geothermal system improvements  

Science Conference Proceedings (OSTI)

Three geothermal wells drilled during the original campus construction vary from 396 m (1,300 ft) to 550 m (1,800 ft). These wells supply all of the heating and part of the cooling needs of the 11-building, 62,200 m{sup 2} (670,000 ft{sup 2}) campus. The combined capacity of the well pumps is 62 L/s(980 gpm) of 89{degrees}C (192{degrees}F) geothermal fluids. Swimming pool and domestic hot water heating impose a small but nearly constant year-round flow requirement. In addition to heating, a portion of the campus is also cooled using the geothermal resource. This is accomplished through the use of an absorption chiller. The chiller, which operates on the same principle as a gas refrigerator, requires a flow of 38 L/s (600 gpm) of geothermal fluid and produces 541 kW (154 tons) of cooling capacity (Rafferty, 1989). The annual operating costs for the system is about $35,000 including maintenance salary, equipment replacement and cost of pumping. This amounts to about $0.05 per square foot per year.

Lienau, P.J. [Geo-Heat Center, Klamath Falls, OR (United States)

1996-08-01T23:59:59.000Z

78

Mapping Fractures In The Medicine Lake Geothermal System | Open Energy  

Open Energy Info (EERE)

Fractures In The Medicine Lake Geothermal System Fractures In The Medicine Lake Geothermal System Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Paper: Mapping Fractures In The Medicine Lake Geothermal System Details Activities (1) Areas (1) Regions (0) Abstract: A major challenge to energy production in the region has been locating high-permability fracture zones in the largely impermeable volcanic host rock. An understanding of the fracture networks will be a key to harnessing geothermal resources in the Cascades Author(s): Steven Clausen, Michal Nemcok, Joseph Moore, Jeffrey Hulen, John Bartley Published: GRC, 2006 Document Number: Unavailable DOI: Unavailable Core Analysis At Medicine Lake Area (Clausen Et Al, 2006) Medicine Lake Geothermal Area Retrieved from "http://en.openei.org/w/index.php?title=Mapping_Fractures_In_The_Medicine_Lake_Geothermal_System&oldid=388927

79

Use of hot-dry-rock geothermal resources for space heating: a case study  

DOE Green Energy (OSTI)

This study shows that a hot dry rock (HDR) geothermal space heat system proposed for the National Aeronautics and Space Administrations's Wallops Flight Center (WFC) will cost $10.9 million, saving $4.1 million over the existing oil heating system over a 30-yr lifetime. The minimal, economically feasible plan for HDR at WFC is shown to be the design of a single-fracture reservoir using a combined HDR preheat and a final oil burner after the first 4 years of operation. The WFC cost savings generalize and range from $3.1 million to $7.2 million for other HDR sites having geothermal temperature gradients ranging from 25/sup 0/C/km to 40/sup 0/C/km and depths to basement rock of 2400 ft or 5700 ft compared to the 30/sup 0/C/km and 9000 ft to basement rock at WFC.

Cummings, R.G.; Arundale, C.J.; Bivins, R.L.; Burness, H.S.; Drake, R.H.; Norton, R.D.

1982-09-01T23:59:59.000Z

80

Blind Geothermal System | Open Energy Information  

Open Energy Info (EERE)

Blind Geothermal System Blind Geothermal System Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Print PDF Blind Geothermal System Dictionary.png Blind Geothermal System: An area with a geothermal heat source, but no modern surface manifestations. Other definitions:Wikipedia Reegle Modern Geothermal Features Typical list of modern geothermal features Hot Springs Fumaroles Warm or Steaming Ground Mudpots, Mud Pools, or Mud Volcanoes Geysers Blind Geothermal System Many geothermal areas show no signs of geothermal activity at the surface if the heated water is too far below or no conduits to the surface are available. An area of geothermal activity with no surface features is referred to as a "blind geothermal system." Examples Want to add an example to this list? Select a Geothermal Resource Area to

Note: This page contains sample records for the topic "rock geothermal systems" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Subterrene rock-melting concept applied to the production of deep geothermal wells  

DOE Green Energy (OSTI)

The drilling of wells comprises a large fraction of the costs of geothermal energy-extraction plants, and billions of dollars for wells will be needed before geothermal energy is nationally significant. Technical and cost studies were made of the application of the Subterrene concept, i.e., excavating and penetrating rocks or soils by melting, to deep wells such as may be used for dry-hot-rock or geopressure geothermal energy extraction systems. Technically, it was found that Subterrene requirements are compatible with those of current rotary drilling practices. Certain features of the rock-melting concept such as the glass lining on the borehole wall, and nonrotation, provide opportunities for the development of better well production techniques in hot wells. A typical optimum-cost well would be rotary-drilled in the upper regions and then rock-melted to total depth. Indicated cost-savings are significant: a 33 percent or 4.5 million dollars reduction from rotary drilled well costs are estimated for a 10 km depth well with bottom hole temperatures of 673 K. Even for normal geothermal gradient conditions, the savings for the 10 km depth is estimated as 23 percent or 2 million dollars.

Altseimer, J.H.

1976-01-01T23:59:59.000Z

82

Enhanced Geothermal Systems (EGS) | Open Energy Information  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Enhanced Geothermal Systems (EGS) (Redirected from EGS) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Print PDF Enhanced Geothermal Systems (EGS) Geothermal Technologies There are many types of Geothermal Technologies that take advantage of the earth's heat: Hydrothermal Systems Enhanced Geothermal Systems (EGS) Sedimentary Geothermal Systems Co-Produced Geothermal Systems Geothermal Direct Use Ground Source Heat Pumps EGS Links Related documents and websites DOE EGS Technical Roadmap DOE EGS Systems Demonstration Projects How EGS Works (Animation) EGS Development (Animation)

83

Geothermal utilization at Castle Oaks Subdivision, Castle Rock, Colorado  

SciTech Connect

Designs of geothermal systems for using warm water from four aquifers of the Denver Basin are presented. Advantages of using heat pumps with the geothermal resource are discussed. Two design cases-one with separate heat load and heat pump, and the other with the heat pump and heat load located at the well site-are evaluated in terms of pump costs, operating costs, and payback periods. The 20-year delivered energy costs for the two geothermal systems would be slightly less than those for natural gas ($5.64 to $6.42 versus $6.70 per million Btu).

Garing, K.L.; Coury, G.E.; Goering, S.W.

1982-04-01T23:59:59.000Z

84

Hot dry rock geothermal energy. Draft final report  

DOE Green Energy (OSTI)

This second EPRI workshop on hot dry rock (HDR) geothermal energy, held in May 1994, focused on the status of worldwide HDR research and development and used that status review as the starting point for discussions of what could and should be done next: by U.S. federal government, by U.S. industry, by U.S. state governments, and by international organizations or through international agreements. The papers presented and the discussion that took place indicate that there is a community of researchers and industrial partners that could join forces, with government support, to begin a new effort on hot dry rock geothermal development. This new heat mining effort would start with site selection and confirmatory studies, done concurrently. The confirmatory studies would test past evaluations against the most current results (from the U.S. site at Fenton Hill, New Mexico, and from the two sites in Japan, the one in Russia, and the two in western Europe) and the best models of relevant physical and economic aspects. Site selection would be done in the light of the confirmatory studies and would be influenced by the need to find a site where success is probable and which is representative enough of other sites so that its success would imply good prospects for success at numerous other sites. The test of success would be circulation between a pair of wells, or more wells, in a way that confirmed, with the help of flow modeling, that a multi-well system would yield temperatures, flows and lifetimes that support economically feasible power generation. The flow modeling would have to have previously achieved its own confirmation from relevant data taken from both heat mining and conventional hydrothermal geothermal experience. There may be very relevant experience from the enhancement of ''hot wet rock'' sites, i.e., sites where hydrothermal reservoirs lack, or have come to lack, enough natural water or steam and are helped by water injected cold and produced hot. The new site would have to be selected in parallel with the confirmatory studies because it would have to be modeled as part of the studies and because its similarity to other candidate sites must be known well enough to assure that results at the selected site are relevant to many others. Also, the industry partners in the joint effort at the new site must be part of the confirmatory studies, because they must be convinced of the economic feasibility. This meeting may have brought together the core of people who can make such a joint effort take place. EPRI sponsored the organization of this meeting in order to provide utilities with an update on the prospects for power generation via heat mining. Although the emerging rules for electric utilities competing in power generation make it very unlikely that the rate-payers of any one utility (or small group of utilities) can pay the differential to support this new heat mining research and development effort, the community represented at this meeting may be able to make the case for national or international support of a new heat mining effort, based on the potential size and economics of this resource as a benefit for the nation as a whole and as a contribution to reduced emissions of fossil CO{sub 2} worldwide.

Not Available

1994-09-01T23:59:59.000Z

85

Geothermal Site Assessment Using the National Geothermal Data System  

Open Energy Info (EERE)

Geothermal Site Assessment Using the National Geothermal Data System Geothermal Site Assessment Using the National Geothermal Data System (NGDS), with Examples from the Hawthorne Ammunition Depot Area Jump to: navigation, search Tool Summary Name: Geothermal Site Assessment Using the National Geothermal Data System (NGDS), with Examples from the Hawthorne Ammunition Depot Area Agency/Company /Organization: University of Nevada-Reno Sector: Energy Focus Area: Renewable Energy, Geothermal Topics: Resource assessment Resource Type: Case studies/examples, Publications Website: www.unr.edu/geothermal/pdffiles/PenfieldGRC2010_GeothermalSiteAssessme Cost: Free Language: English References: Paper[1] "This paper examines the features and functionality of the existing database, its integration into the 50-state NGDS, and its usage in

86

Hybrid Geothermal Heat Pump System Research Geothermal Project | Open  

Open Energy Info (EERE)

Hybrid Geothermal Heat Pump System Research Geothermal Project Hybrid Geothermal Heat Pump System Research Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Hybrid Geothermal Heat Pump System Research Project Type / Topic 1 Recovery Act - Geothermal Technologies Program: Ground Source Heat Pumps Project Type / Topic 2 Topic Area 2: Data Gathering and Analysis Project Description Geothermal, or ground-source heat pump systems have been shown to have superior energy performance to conventional heating and cooling systems in many building types and climates. There has been significant growth in the application of these systems; yet, geothermal systems have only been able to capture a few percent of the heating and cooling market. This is due primarily to the prohibitively high cost of installing the necessary ground loop.

87

Simulation of fluid-rock interactions in a geothermal basin. Final report. [QUAGMR (quasi-active geothermal reservoir)  

DOE Green Energy (OSTI)

General balance laws and constitutive relations are developed for convective hydrothermal geothermal reservoirs. A fully interacting rock-fluid system is considered; typical rock-fluid interactions involve momentum and energy transfer and the dependence of rock porosity and permeability upon the fluid and rock stresses. The mathematical model also includes multiphase (water/steam) effects. A simple analytical model is employed to study heat transfer into/or from a fluid moving in a porous medium. Numerical results show that for fluid velocities typical of geothermal systems (Reynolds number much less than 10), the fluid and the solid may be assumed to be in local thermal equilibrium. Mathematical formalism of Anderson and Jackson is utilized to derive a continuum species transport equation for flow in porous media; this method allows one to delineate, in a rigorous manner, the convective and diffusive mechanisms in the continuum representation of species transport. An existing computer program (QUAGMR) is applied to study upwelling of hot water from depth along a fault; the numerical results can be used to explain local temperature inversions occasionally observed in bore hole measurements.

Garg, S.K.; Blake, T.R.; Brownell, D.H. Jr.; Nayfeh, A.H.; Pritchett, J.W.

1975-09-01T23:59:59.000Z

88

National Geothermal Data System (NGDS)  

DOE Data Explorer (OSTI)

The National Geothermal Data System (NGDS) is a DOE-funded distributed network of databases and data sites. Much of the risk of geothermal energy development is associated with exploring for, confirming and characterizing the available geothermal resources. The overriding purpose of the NGDS is to help mitigate this up-front risk by serving as a central gateway for geothermal and relevant related data as well as a link to distributed data sources. Assessing and categorizing the nation's geothermal resources and consolidating all geothermal data through a publicly accessible data system will support research, stimulate public interest, promote market acceptance and investment, and, in turn, the growth of the geothermal industry. Major participants in the NGDS to date include universities, laboratories, the Arizona Geological Survey and Association of American State Geologists (Arizona Geological Survey, lead), the Geothermal Resources Council, and the U.S. Geological Survey. The Geothermal Energy Association is collaborating with the NGDS to insure that it meets the needs of the geothermal industry. [Copied from http://www.geothermaldata.org/Home.aspx

89

Mathematical Analysis of a Geothermal System.  

E-Print Network (OSTI)

??The issue being examined is to design a more economical and efficient therefore superior geothermal system than currently in use in industry. Current geothermal systems (more)

Erceg, Ivan P.

2008-01-01T23:59:59.000Z

90

Bibliography of the geological and geophysical aspects of hot dry rock geothermal resources  

DOE Green Energy (OSTI)

This is the first issue of an annual compilation of references that are useful to the exploration, understanding and development of the hot dry rock geothermal resource.

Heiken, G.; Sayer, S.

1980-02-01T23:59:59.000Z

91

Hot Dry Rock Geothermal Energy Development Project. Annual report, fiscal year 1977  

DOE Green Energy (OSTI)

The feasibility of extracting geothermal energy from hot dry rock in the earth's crust was investigated. The concept being investigated involves drilling a deep hole, creating an artificial geothermal reservoir at the bottom of the hole by hydraulic fracturing, and then intersecting the fracture with a second borehole. At the beginning of FY77, the downhole system was complete, but the impedance to the flow of fluid was too high to proceed confidently with the planned energy extraction demonstration. Therefore, in FY77 work focused on an intensive investigation of the characteristics of the downhole system and on the development of the necessary tools and techniques for understanding and improving it. Research results are presented under the following section headings: introduction and history; hot dry rock resource assessment and site selection; instrumentation and equipment development; drilling and fracturing; reservoir engineering; energy extraction system; environmental studies; project management and liaison; and, looking back and ahead. (JGB)

Not Available

1978-02-01T23:59:59.000Z

92

Numerical modeling of liquid geothermal systems  

DOE Green Energy (OSTI)

A mathematical model describing the physical behavior of hot-water geothermal systems is presented. The model consists of a set of coupled partial differential equations for heat and mass transfer in porous media and an equation of state relating fluid density to temperature and pressure. The equations are solved numerically using an integrated finite difference method which can treat arbitrary nodal configurations in one, two, or three dimensions. The model is used to analyze cellular convection in permeable rock layers heated from below. Results for cases with constant fluid and rock properties are in good agreement with numerical and experimental results from other authors.

Sorey, M.L.

1978-01-01T23:59:59.000Z

93

Fracture network modeling of a Hot Dry Rock geothermal reservoir  

DOE Green Energy (OSTI)

Fluid flow and tracer transport in a fractured Hot Dry Rock (HDR) geothermal reservoir are modeled using fracture network modeling techniques. The steady state pressure and flow fields are solved for a two-dimensional, interconnected network of fractures with no-flow outer boundaries and constant-pressure source and sink points to simulate wellbore-fracture intersections. The tracer response is simulated by particle tracking, which follows the progress of a representative sample of individual tracer molecules traveling through the network. Solute retardation due to matrix diffusion and sorption is handled easily with these particle tracking methods. Matrix diffusion is shown to have an important effect in many fractured geothermal reservoirs, including those in crystalline formations of relatively low matrix porosity. Pressure drop and tracer behavior are matched for a fractured HDR reservoir tested at Fenton Hill, NM.

Robinson, B.A.

1988-01-01T23:59:59.000Z

94

Geographic Information System At International Geothermal Area...  

Open Energy Info (EERE)

Indonesia (Nash, Et Al., 2002) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Geographic Information System At International Geothermal Area...

95

Federal hot dry rock geothermal energy development program: an overview  

DOE Green Energy (OSTI)

The formulation and evolution of the Federal Hot Dry Rock Geothermal Energy Development Program at the Los Alamos Scientific Laboratory are traced. Program motivation is derived from the enormous potential of the resource. Accomplishments to date, including the establishment and evaluation of the 5-MW/sub t/ Phase 1 reservoir at Fenton Hill, NM and various instrument and equipment developments, are discussed. Future plans presented include (1) establishment of a 20- to 50-MW/sub t/ Phase 2 reservoir at Fenton Hill that will be used to demonstrate longevity and, eventually, electric power production and (2) the selection of a second site at which a direct thermal application will be demonstrated.

Nunz, G.J.

1979-01-01T23:59:59.000Z

96

Potential for hot-dry-rock geothermal energy in the western United States  

SciTech Connect

ABS>The U. S. Geological Survey has identified 1.5 million acres (2800 square miles) of western lands as having a significant potential for geothermal development.'' The LASL for the past 2 years has been actively investigating the potential for and preblems associated with extracting geothermal energy from the much more numerous regions of the western United States containing hot, but essentially dry, rock at moderate depths. A recent survey reveals that about 7% of the 13-state area comprising the Western Heat Flow Province---about 95,000 square miles--is underlain, at a depth of 5 km (16,400 ft), by hot rock at temperature levels above 290 deg C (>550 deg F). In the Los Alamos concept a man- made geothermal reservoir would be formed by first drilling into suitably hot rock, and then creating a very large surface area for heat transfer using conventional hydraulic fracturing techniques developed by the oil industry. After forming a circulation loop by drilling a second hole into the top of the fractured region, the heat contained would be convected to the surface by the buoyant circulation of water, without the need for pumping. The water in the Earth loop would be maintained as a liquid throughout by pressurization at the surface, both increasing the amount of heat transport up the second (withdrawal) hole, and enhancing the rate of heat removal from the fractured reservoir, when compared to steam. Thermal stresses resulting from the cooling of the hot rock in such a man-made reservoir may gradually enlarge the initial fracture system so that its useful lifetime will be greatly extended beyond the planned 10 to 15 years provided by the original reservoir. If these thermal stress cracks grow preferentially downward and outward into regions of hotter rock, as seems probable, the quality of the geothermal source may actually improve as energy is withdrawn from it. (auth)

Brown, D.W.

1973-07-25T23:59:59.000Z

97

Hot dry rock geothermal reservoir engineering  

DOE Green Energy (OSTI)

Two wells, GT-2 and EE-1, were originally drilled to a depth of 9600 ft (2.93 km) and 10,000 ft (3.05 km), respectively, and, after some difficulties, including redrilling of the bottom portion of GT-2, a good fracture connection was made between EE-1 and GT-2B, as the modified GT-2 was called. The circulation system was studied extensively for the purpose of establishing a number of fracture properties. Techniques were developed to determine orientation, geometry, heat exchange area, volume, flow impedance and impedance distribution. A much larger fracture system was then created from a depth of 9620 ft (2.93 km) in EE-1. The techniques used and results obtained in the study of the new and old fracture systems are discussed. (MHR)

Aamodt, R.L.

1980-01-01T23:59:59.000Z

98

Proceedings of the second NATO-CCMS information meeting on dry hot rock geothermal energy  

DOE Green Energy (OSTI)

A summary is presented of the second and last NATO-CCMS (North Atlantic Treaty Organization--Committee on Challenges of Modern Society) Geothermal Pilot Study Information Meeting on Dry Hot Rock Geothermal Energy. Only summaries of the formal presentations are included. Overviews of the Energy Research and Development Administration (ERDA) and the U.S. Geological Survey (USGS) geothermal projects are included with emphasis on the Los Alamos Scientific Laboratory (LASL) Hot Dry Rock Geothermal Energy Development Project. Reports of developments in nine foreign countries and on geothermal projects in US universities are also presented.

Mortensen, J.J. (comp.)

1977-11-01T23:59:59.000Z

99

Environmental development plan: geothermal energy systems  

DOE Green Energy (OSTI)

To ensure that environmental, health, and safety (EH and S) considerations are addressed adequately in the technology decision making process, the Environmental Development Plan (EDP) identifies and evaluates EH and S concerns; defines EH and S research and related assessments to examine or resolve the concerns; provides a coordinated schedule with the technology program for required EH and S research and developement; and indicates the timing for Environmental Assessments, Environmental Impact Statements, Environmental Readiness Documents, and Safety Analysis Reports. This EDP for geothermal energy systems covers all current and planned activities of the DOE Geothermal Energy Systems. Hydrothermal convection systems, geopressured systems, and hot-dry-rock systems are covered. Environmental concerns and requirements for resolution of these concerns are discussed at length. (MHR)

Not Available

1979-08-01T23:59:59.000Z

100

Convective heat transport in geothermal systems  

DOE Green Energy (OSTI)

Most geothermal systems under exploitation for direct use or electrical power production are of the hydrothermal type, where heat is transferred essentially by convection in the reservoir, conduction being secondary. In geothermal systems, buoyancy effects are generally important, but often the fluid and heat flow patterns are largely controlled by geologic features (e.g., faults, fractures, continuity of layers) and location of recharge and discharge zones. During exploitation, these flow patterns can drastically change in response to pressure and temperature declines, and changes in recharge/discharge patterns. Convective circulation models of several geothermal systems, before and after start of fluid production, are described, with emphasis on different characteristics of the systems and the effects of exploitation on their evolution. Convective heat transport in geothermal fields is discussed, taking into consideration (1) major geologic features; (2) temperature-dependent rock and fluid properties; (3) fracture- versus porous-medium characteristics; (4) single- versus two-phase reservoir systems; and (5) the presence of noncondensible gases.

Lippmann, M.J.; Bodvarsson, G.S.

1986-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "rock geothermal systems" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Black Rock I Geothermal Project | Open Energy Information  

Open Energy Info (EERE)

Rock I Geothermal Project Rock I Geothermal Project Project Location Information Coordinates The following coordinate was not recognized: 33°19'59" N, 115°50'3 W.The following coordinate was not recognized: 33°19'59" N, 115°50'3 W. Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":33.3705792,"lon":-115.77401,"alt":0,"address":"33\u00b019'59\" N, 115\u00b050'3 W","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

102

Black Rock II Geothermal Project | Open Energy Information  

Open Energy Info (EERE)

Black Rock II Geothermal Project Black Rock II Geothermal Project Project Location Information Coordinates The following coordinate was not recognized: 33°19'59" N, 115°50'3 W.The following coordinate was not recognized: 33°19'59" N, 115°50'3 W. Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":33.3705792,"lon":-115.77401,"alt":0,"address":"33\u00b019'59\" N, 115\u00b050'3 W","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

103

Isotope Transport and Exchange within the Coso Geothermal System | Open  

Open Energy Info (EERE)

Transport and Exchange within the Coso Geothermal System Transport and Exchange within the Coso Geothermal System Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: Isotope Transport and Exchange within the Coso Geothermal System Details Activities (1) Areas (1) Regions (0) Abstract: We are investigating the plumbing of the Coso geothermal system and the nearby Coso Hot Springs using finite element models of single-phase, variable-density fluid flow, conductive- convective heat transfer, fluid-rock isotope exchange, and groundwater residence times. Using detailed seismic reflection data and geologic mapping, we constructed a regional crosssectional model that extends laterally from the Sierra Nevada to Wildhorse Mesa, west of the Argus Range. The base of the model terminates at the brittle-ductile transition zone. A sensitivity study was

104

A Demonstration System for Capturing Geothermal Energy from Mine Waters  

Open Energy Info (EERE)

System for Capturing Geothermal Energy from Mine Waters System for Capturing Geothermal Energy from Mine Waters beneath Butte, MT Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title A Demonstration System for Capturing Geothermal Energy from Mine Waters beneath Butte, MT Project Type / Topic 1 Recovery Act - Geothermal Technologies Program: Ground Source Heat Pumps Project Type / Topic 2 Topic Area 1: Technology Demonstration Projects Project Description Butte, Montana, like many other mining towns that developed because of either hard-rock minerals or coal, is underlain by now-inactive water-filled mines. In Butte's case, over 10,000 miles of underground workings have been documented, but as in many other mining communities these waters are regarded as more of a liability than asset. Mine waters offer several advantages:

105

The economics of heat mining: An analysis of design options and performance requirements of hot dry rock (HDR) geothermal power systems  

SciTech Connect

A generalized economic model was developed to predict the breakeven price of HDR generated electricity. Important parameters include: (1) resource quality--average geothermal gradient ({sup o}C/km) and well depth, (2) reservoir performance--effective productivity, flow impedance, and lifetime (thermal drawdown rate), (3) cost components--drilling, reservoir formation, and power plant costs and (4) economic factors--discount and interest rates, taxes, etc. Detailed cost correlations based on historical data and results of other studies are presented for drilling, stimulation, and power plant costs. Results of the generalized model are compared to the results of several published economic assessments. Critical parameters affecting economic viability are drilling costs and reservoir performance. For example, high gradient areas are attractive because shallower well depths and/or lower reservoir production rates are permissible. Under a reasonable set of assumptions regarding reservoir impedance, accessible rock volumes and surface areas, and mass flow rates (to limit thermal drawdown rates to about 10 C per year), predictions for HDR-produced electricity result in competitive breakeven prices in the range of 5 to 9 cents/kWh for resources having average gradients above 50 C/km. Lower gradient areas require improved reservoir performance and/or lower well drilling costs.

Tester, Jefferson W.; Herzog, Howard J.

1991-01-25T23:59:59.000Z

106

Hot Dry Rock Geothermal Reservoir Testing- 1978 To 1980 | Open Energy  

Open Energy Info (EERE)

Dry Rock Geothermal Reservoir Testing- 1978 To 1980 Dry Rock Geothermal Reservoir Testing- 1978 To 1980 Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Hot Dry Rock Geothermal Reservoir Testing- 1978 To 1980 Details Activities (3) Areas (1) Regions (0) Abstract: The Phase I Hot Dry Rock Geothermal Energy reservoirs at the Fenton Hill field site grew continuously during Run Segments 2 through 5 (January 1978 to December 1980). Reservoir growth was caused not only by pressurization and hydraulic fracturing, but also by heat-extraction and thermal-contraction effects. Reservoir heat-transfer area grew from 8000 to 50,000 m2 and reservoir fracture volume grew from 11 to 266 m3. Despite this reservoir growth, the water loss rate increased only 30%, under similar pressure environments. For comparable temperature and pressure

107

Computerized international geothermal information systems  

DOE Green Energy (OSTI)

The computerized international geothermal energy information system is reviewed. The review covers establishment of the Italy - United States linked data centers by the NATO Committee on Challenges of Modern Society, through a bilateral agreement, and up to the present time. The result of the information exchange project is given as the bibliographic and numerical data available from the data centers. Recommendations for the exchange of computerized geothermal information at the international level are discussed.

Phillips, S.L.; Lawrence, J.D.; Lepman, S.R.

1980-03-01T23:59:59.000Z

108

Seismic Technology Adapted to Analyzing and Developing Geothermal Systems  

Open Energy Info (EERE)

Technology Adapted to Analyzing and Developing Geothermal Systems Technology Adapted to Analyzing and Developing Geothermal Systems Below Surface-Exposed High-Velocity Rocks Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Seismic Technology Adapted to Analyzing and Developing Geothermal Systems Below Surface-Exposed High-Velocity Rocks Project Type / Topic 1 Recovery Act: Enhanced Geothermal Systems Component Research and Development/Analysis Project Type / Topic 2 Geophysical Exploration Technologies Project Description Historically, areas where the Earth surface is covered by an exposed high-velocity rock layer have been locations where conventional, single-component, seismic P-waves have failed to provide usable geological information. The research will use new seismic sources that emphasize shear waves and new seismic data-acquisition technology based on cable-free data recording to acquire seismic research data across two sites covered with surface-exposed highvelocity rocks. Research tasks will involve acquiring, processing, and interpreting both conventional seismic data and multicomponent seismic data. Scientists at BEG will analyze well logs, cores, and reservoir test data to construct geological models of the targeted geology across each study site.

109

The origin of high-temperature zones in vapor-dominated geothermal systems  

DOE Green Energy (OSTI)

Vapor-dominated geothermal systems are proposed to originate by downward extension (by the ''heat pipe'' mechanism) into hot dry fractured rock above a large cooling igneous intrusion. High temperature zones found by drilling are shallow parts of the original hot dry rock where the penetration of the vapor reservoir was limited, and hot dry rock may extend under much of these reservoirs. An earlier hot water geothermal system may have formed during an early phase of the heating episode.

Truesdell, Alfred H.

1991-01-01T23:59:59.000Z

110

Comparison of two hot dry rock geothermal reservoirs  

DOE Green Energy (OSTI)

Two hot dry rock (HDR) geothermal energy reservoirs were created by hydraulic fracturing of granite at 2.7 to 3.0 km (9000 to 10,000 ft) at the Fenton Hill site, near the Valles Caldera in northern New Mexico. Both reservoirs are research reservoirs, in the sense that both are fairly small, generally yielding 5 MWt or less, and are intended to serve as the basic building blocks of commercial-sized reservoirs, consisting of 10 to 15 similar fractures that would yield approximately 35 MWt over a 10 to 20 yr period. Both research reservoirs were created in the same well-pair, with energy extraction well number 1 (EE-1) serving as the injection well, and geothermal test well number 2 (GT-2) serving as the extraction, or production, well. The first reservoir was created in the low permeability host rock by fracturing EE-1 at a depth of 2.75 km (9020 ft) where the indigenous temperature was 185/sup 0/C (364/sup 0/F). A second, larger reservoir was formed by extending a small, existing fracture at 2.93 km (9620 ft) in the injection well about 100 m deeper and 10/sup 0/C hotter than the first reservoir. The resulting large fracture propagated upward to about 2.6 km (8600 ft) and appeared to Rave an inlet-to-outlet spacing of 300m (1000 ft), more then three times that of the first fracture. Comparisons are made with the first reservoir. Evaluation of the new reservoir was accomplished in two steps: (1) with a 23-day heat extraction experiment that began October 23, 1979, and (2) a second, longer-term heat extraction experiment still in progress, which as of November 25, 1980 has been in effect for 260 days. The results of this current experiment are compared with earlier experiments.

Murphy, H.D.; Tester, J.W.; Potter, R.M.

1980-01-01T23:59:59.000Z

111

Geothermal Environmental Impact Assessment: Subsurface Environmental Assessment for Four Geothermal Systems  

DOE Green Energy (OSTI)

Geothermal systems are described for Imperial Valley and The Geysers, California; Klamath Falls, Oregon; and the Rio Grande Rift Zone, New Mexico; including information on location, area, depth, temperature, fluid phase and composition, resource base and status of development. The subsurface environmental assessment evaluates potential groundwater degradation, seismicity and subsidence. A general discussion on geothermal systems, pollution potential, chemical characteristics of geothermal fluids and environmental effects of geothermal water pollutants is presented as background material. For the Imperial Valley, all publicly available water quality and location data for geothermal and nongeothermal wells in and near the East Mesa, Salton Sea, Heber, Brawley, Dunes and Glamis KGRAs have been compiled and plotted. The geothermal fluids which will be reinjected range in salinity from a few thousand to more than a quarter million ppm. Although Imperial Valley is a major agricultural center, groundwater use in and near most of these KGRAs is minimal. Extensive seismicity and subsidence monitoring networks have been established in this area of high natural seismicity and subsidence. The vapor-dominated Geysers geothermal field is the largest electricity producer in the world. Groundwater in this mountainous region flows with poor hydraulic continuity in fractured rock. Ground and surface water quality is generally good, but high boron concentrations in hot springs and geothermal effluents is of significant concern; however, spent condensate is reinjected. High microearthquake activity is noted around the geothermal reservoir and potential subsidence effects are considered minimal. In Klamath Falls, geothermal fluids up to 113 C (235 F) are used for space heating, mostly through downhole heat exchangers with only minor, relatively benign, geothermal fluid being produced at the surface. Seismicity is low and is not expected to increase. Subsidence is not recognized. Of all geothermal occurrences in the Rio Grande Rift, the Valles Caldera is currently of primary interest. injection of geothermal effluent from hydrothermal production wells should remove any hydrologic hazard due to some potentially noxious constituents. Waters circulating in the LASL Hot Dry Rock experiment are potable. Seismic effects are expected to be minimal. Subsidence effects could develop.

Sanyal, Subir; Weiss, Richard

1978-11-01T23:59:59.000Z

112

S-cubed geothermal technology and experience  

DOE Green Energy (OSTI)

Summaries of ten research projects are presented. They include: equations describing various geothermal systems, geohydrological environmental effects of geothermal power production, simulation of linear bench-scale experiments, simulation of fluid-rock interactions in a geothermal basin, geopressured geothermal reservoir simulator, user-oriented geothermal reservoir simulator, geothermal well test analyses, geothermal seismic exploration, high resolution seismic mapping of a geothermal reservoir, experimental evaluation of geothermal well logging cables, and list of publications. (MHR)

Not Available

1976-04-01T23:59:59.000Z

113

Environmental analysis of the Fenton Hill Hot Dry Rock Geothermal Test Site  

DOE Green Energy (OSTI)

Techniques for the extraction of geothermal energy from hot dry rock within the earth's crust were tested at the first experimental system at Fenton Hill and proved successful. Because new concepts were being tried and new uses of the natural resources were being made, environmental effects were a major concern. Therefore, at all phases of development and operation, the area was monitored for physical, biological, and social factors. The results were significant because after several extended operations, there were no adverse environmental effects, and no detrimental social impacts were detected. Although these results are specific for Fenton Hill, they are applicable to future systems at other locations.

Kaufman, E.L.; Siciliano, C.L.B. (comps.)

1979-05-01T23:59:59.000Z

114

Hot Dry Rock Geothermal Energy Development Program. Annual report, fiscal year 1979  

DOE Green Energy (OSTI)

The Fenton Hill Project is still the principal center for developing methods, equipment, and instrumentation for creating and utilizing HDR geothermal reservoirs. The search for a second site for a similar experimental system in a different geological environment has been intensified, as have the identification and characterization of other HDR areas that may prove suitable for either experimental or commercial development. The Phase I fracture system was enlarged during FY79. Drilling of the injection well of the Phase II system began at Fenton Hill in April 1979. Environmental monitoring of the Fenton Hill area continued through FY79. The environmental studies indicate that the hot dry rock operations have caused no significant environmental impact. Other supporting activities included rock physics, rock mechanics, fracture mapping, and instrumentation development. Two closely related activities - evaluation of the potential HDR energy resource of the US and the selection of a site for development of a second experimental heat-extraction system generally similar to that at Fenton Hill - have resulted in the collection of geology, hydrology, and heat-flow data on some level of field activity in 30 states. The resource-evaluation activity included reconnaissance field studies and a listing and preliminary characterization of US geothermal areas in which HDR energy extraction methods may be applicable. The selection of Site 2 has taken into account such legal, institutional, and economic factors as land ownership and use, proximity to possible users, permitting and licensing requirements and procedures, environmental issues, areal extent of the geothermal area, and visibility to and apparent interest by potential industrial developers.

Cremer, G.M.; Duffield, R.B.; Smith, M.C.; Wilson, M.G. (comps.)

1980-08-01T23:59:59.000Z

115

Hot-dry-rock geothermal-energy development program. Annual report, fiscal year 1981  

DOE Green Energy (OSTI)

During fiscal year 1981, activities of the Hot Dry Rock Geothermal Energy Development Program were concentrated in four principal areas: (1) data collection to permit improved estimates of the hot dry rock geothermal energy resource base of various regions of the United States and of the United States as a whole, combined with detailed investigations of several areas that appear particularly promising either for further energy extraction experiments or for future commercial development; (2) successful completion of a 9-month, continuous, closed-loop, recirculating flow test in the enlarged Phase I System at Fenton Hill, New Mexico - a pressurized-water heat-extraction loop developed in low-permeability granitic rock by hydraulic fracturing; (3) successful completion at a depth of 4084 m (13,933 ft) of well EE-3, the production well of a larger, deeper, and hotter, Phase II System at Fenton Hill. Well EE-3 was directionally drilled with control of both azimuth and inclination. Its inclined section is about 380 m (1250 ft) vertically above the injection well, EE-2, which was completed in FY80; and (4) supporting activities included new developments in downhole instrumentation and equipment, geochemical and geophysical studies, rock-mechanics and fluid-mechanics investigations, computer analyses and modeling, and overall system design. Under an International Energy Agency agreement, the New Energy Development Organization, representing the Government of Japan has joined Kernforschungsanlage-Juelich GmbH, representing the Federal Republic of Germany, and the US Department of Energy as an active participant in the Fenton Hill Hot Dry Rock Project.

Smith, M.C.; Ponder, G.M. (comps.)

1981-01-01T23:59:59.000Z

116

Reconnaissance geophysical studies of the geothermal system in southern  

Open Energy Info (EERE)

geophysical studies of the geothermal system in southern geophysical studies of the geothermal system in southern Raft River Valley, Idaho Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Reconnaissance geophysical studies of the geothermal system in southern Raft River Valley, Idaho Details Activities (4) Areas (1) Regions (0) Abstract: Gravity, aeromagnetic, and telluric current surveys in the southern Raft River have been used to infer the structure and the general lithology underlying the valley. The gravity data indicate the approximate thickness of the Cenozoic rocks and location of the larger normal faults, and the aeromagnetic data indicate the extent of the major Cenozoic volcanic units. The relative ellipse area contour map compiled from the telluric current survey generally conforms to the gravity map except for

117

Economic modeling of electricity production from hot dry rock geothermal reservoirs: methodology and analyses. Final report  

DOE Green Energy (OSTI)

An analytical methodology is developed for assessing alternative modes of generating electricity from hot dry rock (HDR) geothermal energy sources. The methodology is used in sensitivity analyses to explore relative system economics. The methodology used a computerized, intertemporal optimization model to determine the profit-maximizing design and management of a unified HDR electric power plant with a given set of geologic, engineering, and financial conditions. By iterating this model on price, a levelized busbar cost of electricity is established. By varying the conditions of development, the sensitivity of both optimal management and busbar cost to these conditions are explored. A plausible set of reference case parameters is established at the outset of the sensitivity analyses. This reference case links a multiple-fracture reservoir system to an organic, binary-fluid conversion cycle. A levelized busbar cost of 43.2 mills/kWh ($1978) was determined for the reference case, which had an assumed geothermal gradient of 40/sup 0/C/km, a design well-flow rate of 75 kg/s, an effective heat transfer area per pair of wells of 1.7 x 10/sup 6/ m/sup 2/, and plant design temperature of 160/sup 0/C. Variations in the presumed geothermal gradient, size of the reservoir, drilling costs, real rates of return, and other system parameters yield minimum busbar costs between -40% and +76% of the reference case busbar cost.

Cummings, R.G.; Morris, G.E.

1979-09-01T23:59:59.000Z

118

Hot dry rock geothermal reservoir testing: 1978 to 1980  

DOE Green Energy (OSTI)

Experimental results and re-evaluation of the Phase I Hot Dry Rock Geothermal Energy reservoirs at the Fenton Hill field site are summarized. This report traces reservoir growth as demonstrated during Run Segments 2 through 5 (January 1978 to December 1980). Reservoir growth was caused not only by pressurization and hydraulic fracturing, but also by heat extraction and thermal contraction effects. Reservoir heat-transfer area grew from 8000 to 50,000 m/sup 2/ and reservoir fracture volume grew from 11 to 266 m/sup 3/. Despite this reservoir growth, the water loss rate increased only 30%, under similar pressure environments. For comparable temperature and pressure conditions, the flow impedance (a measure of the resistance to circulation of water through the reservoir) remained essentially unchanged, and if reproduced in the Phase II reservoir under development, could result in self pumping. Geochemical and seismic hazards have been nonexistent in the Phase I reservoirs. The produced water is relatively low in total dissolved solids and shows little tendency for corrosion or scaling. The largest microearthquake associated with heat extraction measures less than -1 on the extrapolated Richter scale.

Dash, Z.V.; Murphy, H.D.; Cremer, G.M. (eds.)

1981-11-01T23:59:59.000Z

119

Hot dry rock geothermal energy development program. Semiannual report, October 1, 1978-March 31, 1979  

DOE Green Energy (OSTI)

The potential of energy extracted from hot dry rock (HDR) was investigated as a commercailly feasible alternate energy source. Run Segments 3 and 4 were completed in the prototype reservoir of the Phase I energy-extraction system at Fenton Hill, New Mexico. Results of these tests yielded significant data on the existing system and this information will be applicable to future HDR systems. Plans and operations initiating a Phase II system are underway at the Fenton Hill site. This system, a deeper, hotter commercial-size reservoir, is intended to demonstrate the longevity and economics of an HDR system. Major activity occurred in evaluation of the national resource potential and in characterizing possible future HDR geothermal sites. Work has begun in the institutional and industrial support area to assess the economics and promote commercial interest in HDR systems as an alternate energy source.

Brown, M.C.; Nunz, G.J.; Cremer, G.M.; Smith, M.C.

1979-09-01T23:59:59.000Z

120

Stress and fault rock controls on fault zone hydrology, Coso geothermal  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Stress and fault rock controls on fault zone hydrology, Coso geothermal field, CA Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: Stress and fault rock controls on fault zone hydrology, Coso geothermal field, CA Details Activities (1) Areas (1) Regions (0) Abstract: In crystalline rock of the Coso Geothermal Field, CA, fractures are the primary source of permeability. At reservoir depths, borehole image, temperature, and mud logs indicate fluid flow is concentrated in extensively fractured damage zones of large faults well-oriented for slip.

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121

Hot Dry Rock Geothermal Energy Development in the USA David Duchane and Donald Brown  

E-Print Network (OSTI)

utility options such as pumped storage or compressed air energy storage (CAES) is that the HDR power plant1 Hot Dry Rock Geothermal Energy Development in the USA by David Duchane and Donald Brown Los energy resources lies right beneath our feet in the form of hot dry rock (HDR), the common geologic

122

Electrical Resistivity as an Indicator of Saturation in Fractured Geothermal Reservoir Rocks: Experimental Data and Modeling  

DOE Green Energy (OSTI)

The electrical resistivity of rock cores under conditions representative of geothermal reservoirs is strongly influenced by the state and phase (liquid/vapor) of the pore fluid. In fractured samples, phase change (vaporization/condensation) can result in resistivity changes that are more than an order of magnitude greater than those measured in intact samples. These results suggest that electrical resistivity monitoring of geothermal reservoirs may provide a useful tool for remotely detecting the movement of water and steam within fractures, the development and evolution of fracture systems and the formation of steam caps. We measured the electrical resistivity of cores of welded tuff containing fractures of various geometries to investigate the resistivity contrast caused by active boiling and to determine the effects of variable fracture dimensions and surface area on water extraction from the matrix. We then used the Nonisothermal Unsaturated Flow and Transport model (NUFT) (Nitao, 1998) to simulate the propagation of boiling fronts through the samples. The simulated saturation profiles combined with previously reported measurements of resistivity-saturation curves allow us to estimate the evolution of the sample resistivity as the boiling front propagates into the rock matrix. These simulations provide qualitative agreement with experimental measurements suggesting that our modeling approach may be used to estimate resistivity changes induced by boiling in more complex systems.

Detwiler, R L; Roberts, J J

2003-06-23T23:59:59.000Z

123

36Cl/Cl ratios in geothermal systems- preliminary measurements from the  

Open Energy Info (EERE)

Cl/Cl ratios in geothermal systems- preliminary measurements from the Cl/Cl ratios in geothermal systems- preliminary measurements from the Coso Field Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: 36Cl/Cl ratios in geothermal systems- preliminary measurements from the Coso Field Details Activities (1) Areas (1) Regions (0) Abstract: The {sub 36}Cl/Cl isotopic composition of chlorine in geothermal systems can be a useful diagnostic tool in characterizing hydrologic structure, in determining the origins and age of waters within the systems, and in differentiating the sources of chlorine (and other solutes) in the thermal waters. The {sub 36}Cl/Cl values for several geothermal water samples and reservoir host rock samples from the Coso, California geothermal field have been measured for these purposes. The results

124

Study of Hybrid Geothermal Heat Pump Systems  

Science Conference Proceedings (OSTI)

Hybrid Ground Source Heat Pump systems often combine a traditional geothermal system with either a cooling tower or fluid cooler for heat rejection and a boiler or solar heat collector for heat addition to the loop. These systems offer the same energy efficiency benefits as full geothermal systems to utilities and their customers but at a potentially lower first cost. Many hybrid systems have materialized to resolve heat buildup in full geothermal system loops where loop temperatures continue to rise as ...

2010-12-06T23:59:59.000Z

125

Hot Dry Rock geothermal energy--- A new energy agenda for the twenty-first century  

SciTech Connect

Hot Dry Rock (HDR) geothermal energy, which utilizes the natural heat contained in the earth's crust, can provide a widely available source of nonpolluting energy. It can help mitigate the continued warming of the earth through the ''greenhouse effect,'' and the accelerating destruction of forests and crops by acid rain, two of the major environmental consequences of our ever-increasing use of fossil fuels for heating and power generation. In addition, HDR, as a readily available source of indigenous energy, can reduce our nation's dependence on imported oil, enhancing national security and reducing our trade deficit. The earth's heat represents an almost unlimited source of energy that can begin to be exploited within the next decade through the HDR heat-mining concept being actively developed in the United States and in several other countries. On a national scale, we can begin to develop this new energy source, using it directly for geothermal power or indirectly in hybrid geothermal/fossil-fueled systems, in diverse applications such as: baseload power generation, direct heat use, feedwater heating in conventional power plants, and pumped storage/load leveling power generation. This report describes the nature of the HDR resource and the technology required to implement the heat-mining concept in several applications. An assessment of the requirements for establishing HDR feasibility is presented in the context of providing a commercially competitive energy source. 37 refs., 6 figs.

Tester, J.W.; Brown, D.W.; Potter, R.M.

1989-07-01T23:59:59.000Z

126

Hot Dry Rock geothermal energy--- A new energy agenda for the twenty-first century  

DOE Green Energy (OSTI)

Hot Dry Rock (HDR) geothermal energy, which utilizes the natural heat contained in the earth's crust, can provide a widely available source of nonpolluting energy. It can help mitigate the continued warming of the earth through the ''greenhouse effect,'' and the accelerating destruction of forests and crops by acid rain, two of the major environmental consequences of our ever-increasing use of fossil fuels for heating and power generation. In addition, HDR, as a readily available source of indigenous energy, can reduce our nation's dependence on imported oil, enhancing national security and reducing our trade deficit. The earth's heat represents an almost unlimited source of energy that can begin to be exploited within the next decade through the HDR heat-mining concept being actively developed in the United States and in several other countries. On a national scale, we can begin to develop this new energy source, using it directly for geothermal power or indirectly in hybrid geothermal/fossil-fueled systems, in diverse applications such as: baseload power generation, direct heat use, feedwater heating in conventional power plants, and pumped storage/load leveling power generation. This report describes the nature of the HDR resource and the technology required to implement the heat-mining concept in several applications. An assessment of the requirements for establishing HDR feasibility is presented in the context of providing a commercially competitive energy source. 37 refs., 6 figs.

Tester, J.W.; Brown, D.W.; Potter, R.M.

1989-07-01T23:59:59.000Z

127

Geothermal: Sponsored by OSTI -- Seismic Technology Adapted to...  

Office of Scientific and Technical Information (OSTI)

Seismic Technology Adapted to Analyzing and Developing Geothermal Systems Below Surface-Exposed High-Velocity Rocks Final Report Geothermal Technologies Legacy Collection HelpFAQ...

128

LASL hot dry rock geothermal energy development project  

DOE Green Energy (OSTI)

The history of the hot-dry-rock project is traced. Efforts to establish a two-hole and connecting fracture system on the southwest flank of the Valles Caldera in north-central New Mexico are summarized. Problems encountered in drilling and hydraulic fracturing are described. Current results with the loop operation for heat extraction are encouraging, and plans for a second energy extraction hole are underway. (JBG)

Hill, J.H.

1978-01-01T23:59:59.000Z

129

Modeling Fluid Flow and Electrical Resistivity in Fractured Geothermal Reservoir Rocks  

DOE Green Energy (OSTI)

Phase change of pore fluid (boiling/condensing) in rock cores under conditions representative of geothermal reservoirs results in alterations of the electrical resistivity of the samples. In fractured samples, phase change can result in resistivity changes that are more than an order of magnitude greater than those measured in intact samples. These results suggest that electrical resistivity monitoring may provide a useful tool for monitoring the movement of water and steam within fractured geothermal reservoirs. We measured the electrical resistivity of cores of welded tuff containing fractures of various geometries to investigate the resistivity contrast caused by active boiling and to determine the effects of variable fracture dimensions and surface area on water extraction. We then used the Nonisothermal Unsaturated Flow and Transport model (NUFT) (Nitao, 1998) to simulate the propagation of boiling fronts through the samples. The simulated saturation profiles combined with previously reported measurements of resistivity-saturation curves allow us to estimate the evolution of the sample resistivity as the boiling front propagates into the rock matrix. These simulations provide qualitative agreement with experimental measurements suggesting that our modeling approach may be used to estimate resistivity changes induced by boiling in more complex systems.

Detwiler, R L; Roberts, J J; Ralph, W; Bonner, B P

2003-01-14T23:59:59.000Z

130

Enhanced Geothermal Systems (EGS) R&D Program: US Geothermal Resources Review and Needs Assessment  

DOE Green Energy (OSTI)

The purpose of this report is to lay the groundwork for an emerging process to assess U.S. geothermal resources that might be suitable for development as Enhanced Geothermal Systems (EGS). Interviews of leading geothermists indicate that doing that will be intertwined with updating assessments of U.S. higher-quality hydrothermal resources and reviewing methods for discovering ''hidden'' hydrothermal and EGS resources. The report reviews the history and status of assessment of high-temperature geothermal resources in the United States. Hydrothermal, Enhanced, and Hot Dry Rock resources are addressed. Geopressured geothermal resources are not. There are three main uses of geothermal resource assessments: (1) They inform industry and other interest parties of reasonable estimates of the amounts and likely locations of known and prospective geothermal resources. This provides a basis for private-sector decisions whether or not to enter the geothermal energy business at all, and for where to look for useful resources. (2) They inform government agencies (Federal, State, local) of the same kinds of information. This can inform strategic decisions, such as whether to continue to invest in creating and stimulating a geothermal industry--e.g., through research or financial incentives. And it informs certain agencies, e.g., Department of Interior, about what kinds of tactical operations might be required to support such activities as exploration and leasing. (3) They help the experts who are performing the assessment(s) to clarify their procedures and data, and in turn, provide the other two kinds of users with a more accurate interpretation of what the resulting estimates mean. The process of conducting this assessment brings a spotlight to bear on what has been accomplished in the domain of detecting and understanding reservoirs, in the period since the last major assessment was conducted.

Entingh, Dan; McLarty, Lynn

2000-11-30T23:59:59.000Z

131

Geothermal Data from the National Geothermal Data System (NGDS)  

DOE Data Explorer (OSTI)

The National Geothermal Data System (NGDS) is a distributed data system providing access to information resources related to geothermal energy from a network of data providers. Data are contributed by academic researchers, private industry, and state and federal agencies. Built on a scalable and open platform through the U.S. Geoscience Information Network (USGIN), NGDS respects data provenance while promoting shared resources.Since NGDS is built using a set of open protocols and standards, relying on the Open Geospatial Consortium (OGC) and International Organization for Standardization (ISO), members of the community may access the data in a variety of proprietary and open-source applications and software. In addition, developers can add functionality to the system by creating new applications based on the open protocols and standards of the NGDS. The NGDS, supported by the U.S. Department of Energys Geothermal Technology Program, is intended to provide access to all types of geothermal data to enable geothermal analysis and widespread public use in an effort to reduce the risk of geothermal energy development [copied from http://www.geothermaldata.org/page/about]. See the long list of data contributors at http://geothermaldata.org/page/data-types-and-contributors#data-contributors.

132

Mining earth's heat: development of hot-dry-rock geothermal reservoirs  

DOE Green Energy (OSTI)

The energy-extraction concept of the Hot Dry Rock (HDR) Geothermal Program, as initially developed by the Los Alamos National Laboratory, is to mine this heat by creating a man-made reservoir in low-permeability, hot basement rock. This concept has been successfully proven at Fenton Hill in northern New Mexico by drilling two holes to a depth of approximately 3 km (10,000 ft) and a bottom temperature of 200/sup 0/C (392/sup 0/F), then connecting the boreholes with a large-diametervertical hydraulic fracture. Water is circulated down one borehole, heated by the hot rock, and rises up the second borehole to the surface where the heat is extracted and the cooled water is reinjected into the underground circulation loop. This system has operated for a cumulative 416 days during engineering and reservoir testing. An energy equivalent of 3 to 5 MW(t) was produced without adverse environmental problems. During one test, a generator was installed in the circulation loop and produced 60 kW of electricity. A second-generation system, recently drilled to 4.5 km (15,000 ft) and temperatures of 320/sup 0/C (608/sup 0/F), entails creating multiple, parallel fractures between a pair of inclined boreholes. This system should produce 5 to 10 MW(e) for 20 years. Significant contributions to underground technology have been made through the development of the program.

Pettitt, R.A.; Becker, N.M.

1983-01-01T23:59:59.000Z

133

Calpine Enhanced Geothermal Systems Project Final Environmental...  

NLE Websites -- All DOE Office Websites (Extended Search)

Calpine Enhanced Geothermal Systems Project Final Environmental Assessment June 2010 Prepared for: U.S. Department of Energy 1617 Cole Boulevard Golden, CO 80401 Prepared by: RMT...

134

Geographic Information Systems- Tools For Geotherm Exploration...  

Open Energy Info (EERE)

that can help the geothermal industry in exploration, tracer analysis, infrastructure management, and the general distribution and use of data. GIS systems are highly...

135

Summary of talks third annual hot dry rock geothermal information conference  

DOE Green Energy (OSTI)

Three basic comparisons can be made between weapon system development and energy system development in the US--driving factors, system lifetime, and development time. Weapon system development and response is determined by a perceived threat to national security. Because the threat can change radically in this high technology atmosphere, weapon systems are usually designed for a 5 to 20 year lifetime. Development time from idea to capability is about 20 years on the average. In contrast, energy system development has been influenced by economics--demand, supply, return on investment--until the recent threat created by our dependence on oil. Energy systems are expected to operate 20 to 50 years and even longer. Development time is correspondingly long, i.e., 40 years from idea to large-scale use. The US needs to adopt a ''defense-oriented'' approach to protect its threatened energy security. Geothermal energy from hot dry rock is a new concept. The Hot Dry Rock Program is designed to minimize development time and may become a prime example of how a recognized threat to energy security can be answered by combined government/industry effort.

Gaddy, James

1980-10-29T23:59:59.000Z

136

Environmental investigations associated with the LASL hot dry rock geothermal energy development project  

DOE Green Energy (OSTI)

The Los Alamos Scientific Laboratory (LASL) is currently evaluating the feasibility of extracting thermal energy from hot dry rock (HDR) geothermal reservoirs. An overview of the environmental studies that LASL has conducted relative to its HDR Geothermal Energy Development Project is presented. Because HDR geothermal technology is a new field of endeavor, environmental guidelines have not been established. It is anticipated that LASL's research will lead to the techniques necessary to mitigate undesirable environmental impacts in future HDR developments. To date, results of environmental investigations have been positive in that no undesirable environmental impacts have been found.

Rea, K.H.

1977-12-01T23:59:59.000Z

137

The xerolithic geothermal (``hot dry rock``) energy resource of the United States: An update  

DOE Green Energy (OSTI)

This report presents revised estimates, based upon the most current geothermal gradient data, of the xerolithic geothermal (``hot dry rock`` or HDR) energy resources of the United States. State-by-state tabular listings are provided of the HDR energy resource base, the accessible resource base, and the potentially useful resource base. The latter further subdivided into components with potential for electricity generation, process heat, and space heat. Comparisons are made with present estimates of fossil fuel reserves. A full-sized geothermal gradient contour map is provided as a supplement in a pocket inside the back cover of the report.

Nunz, G.J.

1993-07-01T23:59:59.000Z

138

Hot dry rock geothermal energy development program. Annual report, fiscal year 1980  

DOE Green Energy (OSTI)

Investigation and flow testing of the enlarged Phase I heat-extraction system at Fenton Hill continued throughout FY80. Temperature drawdown observed at that time indicated an effective fracture of approximately 40,000 to 60,000 m/sup 2/. In May 1980, hot dry rock (HDR) technology was used to produce electricity in an interface demonstration experiment at Fenton Hill. A 60-kVA binary-cycle electrical generator was installed in the Phase I surface system and heat from about 3 kg/s of geothermal fluid at 132/sup 0/C was used to boil Freon R-114, whose vapor drove a turboalternator. A Phase II system was designed and is now being constructed at Fenton Hill that should approach commercial requirements. Borehole EE-2, the injection well, was completed on May 12, 1980. It was drilled to a vertical depth of about 4500 m, where the rock temperature is approximately 320/sup 0/C. The production well, EE-3 had been drilled to a depth of 3044 m and drilling was continuing. Environmental monitoring of Fenton Hill site continued. Development of equipment, instruments, and materials for technical support at Fenton Hill continued during FY80. Several kinds of models were also developed to understand the behavior of the Phase I system and to develop a predictive capability for future systems. Data from extensive resource investigations were collected, analyzed, and assembled into a geothermal gradient map of the US, and studies were completed on five specific areas as possible locations for HDR Experimental Site 2.

Cremer, G.M. (comp.)

1981-07-01T23:59:59.000Z

139

The furnace in the basement: Part 1, The early days of the Hot Dry Rock Geothermal Energy Program, 1970--1973  

DOE Green Energy (OSTI)

This report presents the descriptions of the background information and formation of the Los Alamos Scientific Laboratory Geothermal Energy Group. It discusses the organizational, financial, political, public-relations,geologic, hydrologic, physical, and mechanical problems encountered by the group during the period 1970--1973. It reports the failures as well as the successes of this essential first stage in the development of hot dry rock geothermal energy systems.

Smith, M.C.

1995-09-01T23:59:59.000Z

140

Development of a Hydrothermal Spallation Drilling System for EGS Geothermal  

Open Energy Info (EERE)

Hydrothermal Spallation Drilling System for EGS Geothermal Hydrothermal Spallation Drilling System for EGS Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Development of a Hydrothermal Spallation Drilling System for EGS Project Type / Topic 1 Recovery Act: Enhanced Geothermal Systems Component Research and Development/Analysis Project Type / Topic 2 Drilling Systems Project Description Potter Drilling has recently demonstrated hydrothermal spallation drilling in the laboratory. Hydrothermal spallation drilling creates boreholes using a focused jet of superheated water, separating individual grains ("spalls") from the rock surface without contact between the rock and the drill head. This process virtually eliminates the need for tripping. Previous tests of flame-jet spallation achieved ROP of 50 ft/hr and higher in hard rock with minimal wear on the drilling assembly, but operating this technology in an air-filled borehole created challenges related to cuttings transport and borehole stability. The Potter Drilling system uses a water based jet technology in a fluid-filled borehole and as a result has the potential to achieve similarly high ROP that is uncompromised by stability or cuttings transport issues.

Note: This page contains sample records for the topic "rock geothermal systems" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

An Updated Numerical Model Of The Larderello-Travale Geothermal System,  

Open Energy Info (EERE)

Of The Larderello-Travale Geothermal System, Of The Larderello-Travale Geothermal System, Italy Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: An Updated Numerical Model Of The Larderello-Travale Geothermal System, Italy Details Activities (0) Areas (0) Regions (0) Abstract: Larderello-Travale is one of the few geothermal systems in the world that is characterized by a reservoir pressure much lower than hydrostatic. This is a consequence of its natural evolution from an initial liquid-dominated to the current steam-dominated system. Beneath a nearly impermeable cover, the geothermal reservoir consists of carbonate-anhydrite formations and, at greater depth, by metamorphic rocks. The shallow reservoir has temperatures in the range of 220-250°C, and pressures of about 20 bar at a depth of 1000 m, while the deep metamorphic reservoir has

142

Mathematical modeling of the behavior of geothermal systems under exploitation  

DOE Green Energy (OSTI)

Analytical and numerical methods have been used in this investigation to model the behavior of geothermal systems under exploitation. The work is divided into three parts: (1) development of a numerical code, (2) theoretical studies of geothermal systems, and (3) field applications. A new single-phase three-dimensional simulator, capable of solving heat and mass flow problems in a saturated, heterogeneous porous or fractured medium has been developed. The simulator uses the integrated finite difference method for formulating the governing equations and an efficient sparse solver for the solution of the linearized equations. In the theoretical studies, various reservoir engineering problems have been examined. These include (a) well-test analysis, (b) exploitation strategies, (c) injection into fractured rocks, and (d) fault-charged geothermal reservoirs.

Bodvarsson, G.S.

1982-01-01T23:59:59.000Z

143

Co-Produced Geothermal Systems | Open Energy Information  

Open Energy Info (EERE)

Produced Geothermal Systems Produced Geothermal Systems Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Print PDF Co-Produced Geothermal Systems Geothermal Technologies There are many types of Geothermal Technologies that take advantage of the earth's heat: Hydrothermal Systems Enhanced Geothermal Systems (EGS) Sedimentary Geothermal Systems Co-Produced Geothermal Systems Geothermal Direct Use Ground Source Heat Pumps Dictionary.png Co-Produced Geothermal System: Co-Produced water is the water that is produced as a by-product during oil and gas production. If there is enough water produced at a high enough temperature co-produced water can be utilized for electricity production. Other definitions:Wikipedia Reegle General Air Cooled Co-Produced geothermal system demonstration at RMOTC oil site.

144

Petrologic considerations for hot dry rock geothermal site selection in the Clear Lake Region, California  

DOE Green Energy (OSTI)

The Clear Lake area is well known for anomalous heat flow, thermal springs, hydrothermal mineral deposits, and Quaternary volcanism. These factors, along with the apparent lack of a large reservoir of geothermal fluid north of Collayomi fault make the Clear Lake area an attractive target for hot dry rock (HDR) geothermal development. Petrologic considerations provide some constraints on site selection for HDR development. Spatial and temporal trends in volcanism in the Coast Ranges indicate that magmatism has migrated to the north with time, paralleling passage of the Mendocino triple junction and propagation of the San Andreas fault. Volcanism in the region may have resulted from upwelling of hot asthenosphere along the southern margin of the subducted segment of the Gorda plate. Spatial and temporal trends of volcanism within the Clear Lake volcanic field are similar to larger-scale trends of Neogene volcanism in the Cost Ranges. Volcanism (especially for silicic compositions) shows a general migration to the north over the {approximately}2 Ma history of the field, with the youngest two silicic centers located at Mt. Konocti and Borax Lake. The Mt. Konocti system (active from {approximately} 0.6 to 0.3 Ma) was large and long-lived, whereas the Borax Lake system is much smaller but younger (0.09 Ma). Remnants of silicic magma bodies under Mt. Konocti may be in the latter stages of cooling, whereas a magma body centered under Borax Lake may be in the early stages of development. The existence of an upper crustal silicic magma body of under Borax Lake has yet to be demonstrated by passive geophysics, however, subsurface temperatures in the area as high (> 200{degrees}C at 2000 m) as those beneath the Mt. Konocti area. Based on petrologic considerations alone, the Mt. Konocti-Borax Lake area appears to be the most logical choice for HDR geothermal development in the region.

Stimac, J.; Goff, F. (Los Alamos National Lab., NM (United States)); Hearn, B.C. Jr. (US Geological Survey, Reston, VA, Branch of Lithospheric Processes (United States))

1992-01-01T23:59:59.000Z

145

Quantitative model of vapor dominated geothermal reservoirs as heat pipes in fractured porous rock  

DOE Green Energy (OSTI)

We present a numerical model of vapor-dominated reservoirs which is based on the well-known conceptual model of White, Muffler, and Truesdell. Computer simulations show that upon heat recharge at the base, a single phase liquid-dominated geothermal reservoir in fractured rock with low matrix permeability will evolve into a two-phase reservoir with B.P.D. (boiling point-for-depth) pressure and temperature profiles. A rather limited discharge event through cracks in the caprock, involving loss of only a few percent of fluids in place, is sufficient to set the system off to evolve a vapor-dominated state. The attributes of this state are discussed, and some features requiring further clarification are identified. 26 refs., 5 figs.

Pruess, K.

1985-03-01T23:59:59.000Z

146

Geothermal system saving money at fire station | Department of...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Geothermal system saving money at fire station Geothermal system saving money at fire station April 9, 2010 - 3:45pm Addthis Joshua DeLung What will the project do? A geothermal...

147

Development of Exploration Methods for Engineered Geothermal Systems  

Open Energy Info (EERE)

Exploration Methods for Engineered Geothermal Systems Exploration Methods for Engineered Geothermal Systems through Integrated Geophysical, Geologic and Geochemical Interpretation. Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Development of Exploration Methods for Engineered Geothermal Systems through Integrated Geophysical, Geologic and Geochemical Interpretation. Project Type / Topic 1 Recovery Act: Enhanced Geothermal Systems Component Research and Development/Analysis Project Type / Topic 2 Geophysical Exploration Technologies Project Description A comprehensive, interdisciplinary approach is proposed using existing geophysical exploration technology coupled with new seismic techniques and subject matter experts to determine the combination of geoscience data that demonstrates the greatest potential for identifying EGS drilling targets using non-invasive techniques. This proposed exploration methodology is expected to increase spatial resolution and reduce the non-uniqueness that is inherent in geological data, thereby reducing the uncertainty in the primary selection criteria for identifying EGS drilling targets. These criteria are, in order of importance: (1) temperatures greater than 200-250°C at 1-5 km depth; (2) rock type at the depth of interest, and; (3) stress regime.

148

Enhanced Geothermal Systems (EGS) R&D Program: Monitoring EGS-Related Research  

DOE Green Energy (OSTI)

This report reviews technologies that could be applicable to Enhanced Geothermal Systems development. EGS covers the spectrum of geothermal resources from hydrothermal to hot dry rock. We monitored recent and ongoing research, as reported in the technical literature, that would be useful in expanding current and future geothermal fields. The literature review was supplemented by input obtained through contacts with researchers throughout the United States. Technologies are emerging that have exceptional promise for finding fractures in nonhomogeneous rock, especially during and after episodes of stimulation to enhance natural permeability.

McLarty, Lynn; Entingh, Daniel; Carwile, Clifton

2000-09-29T23:59:59.000Z

149

Draft environmental impact report. California Department of Water Resources, Bottle Rock geothermal power plant, Lake County, CA  

SciTech Connect

The California Department of Water Resources (DWR) proposes to construct the Bottle Rock power plant, a 55 MW geothermal power plant, at The Geysers Known Geothermal Resource Area (KGRA). The plant is projected to begin operation in April of 1983, and will be located in Lake County near the Sonoma County line on approximately 7.2 acres of the Francisco leasehold. The steam to operate the power plant, approximately 1,000,000 pounds/h, will be provided by McCulloch Geothermal Corporation. The power plant's appearance and operation will be basically the same as the units in operation or under construction in the KGRA. The power plant and related facilities will consist of a 55 MW turbine generator, a 1.1 mile (1.81 km) long transmission line, a condensing system, cooling tower, electrical switchyard, gas storage facility, cistern, and an atmospheric emission control system. DWR plans to abate hydrogen sulfide (H/sub 2/S) emissions through the use of the Stretford Process which scrubs the H/sub 2/S from the condenser vent gas stream and catalytically oxides the gas to elemental sulfur. If the Stretford Process does not meet emission limitations, a secondary H/sub 2/S abatement system using hydrogen peroxide/iron catalyst is proposed. The Bottle Rock project and other existing and future geothermal projects in the KGRA may result in cumulative impacts to soils, biological resources, water quality, geothermal steam resources, air quality, public health, land use, recreation, cultural resources, and aesthetics.

1979-12-01T23:59:59.000Z

150

Draft environmental impact report. California Department of Water Resources, Bottle Rock geothermal power plant, Lake County, CA  

DOE Green Energy (OSTI)

The California Department of Water Resources (DWR) proposes to construct the Bottle Rock power plant, a 55 MW geothermal power plant, at The Geysers Known Geothermal Resource Area (KGRA). The plant is projected to begin operation in April of 1983, and will be located in Lake County near the Sonoma County line on approximately 7.2 acres of the Francisco leasehold. The steam to operate the power plant, approximately 1,000,000 pounds/h, will be provided by McCulloch Geothermal Corporation. The power plant's appearance and operation will be basically the same as the units in operation or under construction in the KGRA. The power plant and related facilities will consist of a 55 MW turbine generator, a 1.1 mile (1.81 km) long transmission line, a condensing system, cooling tower, electrical switchyard, gas storage facility, cistern, and an atmospheric emission control system. DWR plans to abate hydrogen sulfide (H/sub 2/S) emissions through the use of the Stretford Process which scrubs the H/sub 2/S from the condenser vent gas stream and catalytically oxides the gas to elemental sulfur. If the Stretford Process does not meet emission limitations, a secondary H/sub 2/S abatement system using hydrogen peroxide/iron catalyst is proposed. The Bottle Rock project and other existing and future geothermal projects in the KGRA may result in cumulative impacts to soils, biological resources, water quality, geothermal steam resources, air quality, public health, land use, recreation, cultural resources, and aesthetics.

Not Available

1979-12-01T23:59:59.000Z

151

The UK geothermal hot dry rock R&D programme  

Science Conference Proceedings (OSTI)

The UK hot dry rock research and development programme is funded by the Department of Energy and aims to demonstrate the feasibility of commercial exploitation of HDR in the UK. The philosophy of the UK programme has been to proceed to a full-scale prototype HDR power station via a number of stages: Phase 1--Experiments at shallow depth (300 m) to assess the feasibility of enhancing the permeability of the rock. Phase 2--Studies at intermediate depth (2500 m) to determine the feasibility of creating a viable HDR subsurface heat exchanger. Phase 3--Establishment of an HDR prototype at commercial depth. The programme has run over a 15 year period, and has been formally reviewed at stages throughout its progress. The 1987 review towards the end of Phase 2 identified a number of technical objectives for continuing research and proposed that the initial design stage of the deep HDR prototype should start. Phase 3A is now complete. It addressed: the feasibility of creating an underground HDR heat exchanger suitable for commercial operation; techniques for improving hydraulic performance and correcting short circuits in HDR systems; modeling of the performance, resource size and economic aspects of HDR systems. The work has been conducted by a number of contractors, including Cambome School of Mines, Sunderland and Sheffield City Polytechnics and RTZ Consultants Limited. This paper focuses upon the experimental work at Rosemanowes in Cornwall and the recently completed conceptual design of a prototype HDR power station. The economics of HDR-generated electricity are also discussed and the conclusions of a 1990 program review are presented. Details of the HDR program to 1994, as announced by the UK Department of Energy in February 1991, are included.

MacDonald, Paul; Stedman, Ann; Symons, Geoff

1992-01-01T23:59:59.000Z

152

Unique aspects of drilling and completing hot-dry-rock geothermal wells  

DOE Green Energy (OSTI)

Drilling operations at the Fenton Hill Hot Dry Rock (HDR) Geothermal Test Site have led to numerous developments needed to solve the problems caused by a very harsh downhole environment. A pair of deep wells were drilled to approximately 15,000 ft (4.6 km); formation temperatures were in excess of 600/sup 0/F (300/sup 0/C). The wells were directionally drilled, inclined at 35/sup 0/, one above the other, in a direction orthogonal to the least principal stress field. The well site is near the flank of a young silicic composite volcano in the Jemez Mountains of northern New Mexico. The completion of this pair of wells is unique in reservoir development. The lower well was planned as a cold water injector which will be cooled by the introduced water from the static geothermal gradient to about 80/sup 0/F (25/sup 0/C). The upper well will be heated during production to over 500/sup 0/F (250/sup 0/C). The well pair is designed to perform as a closed loop heat-extraction system connected by hydraulic fractures with a vertical spacing of 1200 ft between the wells. These conditions strongly constrain the drilling technique, casing design, cement formulation, and cementing operations.

Carden, R.S.; Nicholson, R.W.; Pettitt, R.A.; Rowley, J.C.

1983-01-01T23:59:59.000Z

153

Development of hot dry rock geothermal resources; technical and economic issues  

DOE Green Energy (OSTI)

Technical and economic issues related to the commercial feasibility of hot dry rock geothermal energy for producing electricity and heat are discussed. Topics covered include resource characteristics, reservoir thermal capacity and lifetime, drilling and surface plant costs, financial risk and anticipated rate of return. The current status of research and deveopment efforts in the US are also summarized.

Tester, J.W.

1980-01-01T23:59:59.000Z

154

Philip, South Dakota geothermal district heating systems  

SciTech Connect

The geothermal heating project in Philip, South Dakota which uses the waste water from the Haakon School has now been in operation for 15 years. This project was one of the 23 cost shared by the U.S. DOE starting in 1978, of which 15 became operational. This article describes the geothermal heating system for eight buildings in downtown Philip.

Lund, J.W.

1997-12-01T23:59:59.000Z

155

NUMERICAL SIMULATION OF RESERVOIR COMPACTION IN LIQUID DOMINATED GEOTHERMAL SYSTEMS  

E-Print Network (OSTI)

13. modeling of liquid geothermal systems: Ph.D. thesis,of water dominated geothermal fields with large temper~of land subsidence in geothermal areas: Proc. 2nd Int. Symp.

Lippmann, M.J.

2010-01-01T23:59:59.000Z

156

Strategies To Detect Hidden Geothermal Systems Based On Monitoring...  

Open Energy Info (EERE)

Geothermal Systems Based On Monitoring and Analysis Of CO2 In The Near-Surface Environment Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article:...

157

Assessment of Hybrid Geothermal Heat Pump Systems - Technology...  

NLE Websites -- All DOE Office Websites (Extended Search)

cool- ing needs of the building and offers general guidelines Assessment of Hybrid Geothermal Heat Pump Systems Geothermal heat pumps offer attractive choice for space...

158

TRACING FLUID SOURCES IN THE COSO GEOTHERMAL SYSTEM USING FLUID...  

Open Energy Info (EERE)

TRACING FLUID SOURCES IN THE COSO GEOTHERMAL SYSTEM USING FLUID-INCLUSION GAS CHEMISTRY Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: TRACING...

159

A Geothermal District-Heating System and Alternative Energy Research...  

Open Energy Info (EERE)

Geothermal District-Heating System and Alternative Energy Research Park on the NM Tech Campus Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project...

160

Reconnaissance geophysical studies of the geothermal system in...  

Open Energy Info (EERE)

geophysical studies of the geothermal system in southern Raft River Valley, Idaho Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Reconnaissance...

Note: This page contains sample records for the topic "rock geothermal systems" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Geothermal Systems of the Yellowstone Caldera Field Trip Guide  

Science Conference Proceedings (OSTI)

Geothermal studies are proceedings on two fronts in the West Yellowstone area. High-temperature resources for the generation of electricity are being sought in the Island Park area, and lower temperatures resources for direct applications, primarily space heating, are being explored for near the town of West Yellowstone. Potential electric geothermal development in the Island Park area has been the subject of widespread publicity over fears of damage to thermal features in Yellowstone Park. At the time of writing this guide, companies have applied for geothermal leases in the Island Park area, but these leases have not yet been granted by the US Forest Service. The Senate is now discussing a bill that would regulate geothermal development in Island Park; outcome of this debate will determine the course of action on the lease applications. The Island Park area was the site of two cycles of caldera activity, with major eruptions at 2.0 and 1.2 million years ago. The US Geological Survey estimates that 16,850 x 10{sup 18} joules of energy may remain in the system. Geothermal resources suitable for direct applications are being sought in the West Yellowstone vicinity by the Montana Bureau of Mines and Geology, under funding from the US Department of Energy. West Yellowstone has a mean annual temperature of 1-2 C. Research thus far suggests that basement rocks in the vicinity are at a depth of about 600 m and are probably similar to the rocks exposed north of Hebgen Lake, where Precambrian, Paleozoic and Mesozoic rocks have been mapped. A few sites with anomalously warm water have been identified near the town. Work is continuing on this project.

Foley, Duncan; Neilson, Dennis L.; Nichols, Clayton R.

1980-09-08T23:59:59.000Z

162

The hot dry rock geothermal potential of the Susanville (CA) area  

DOE Green Energy (OSTI)

A portion of northeastern California that lies within the Basin and Range Province represents a large, untapped geothermal energy resource in the form of hot, but essential impermeable, rock. If a means of developing sufficient permeability in the deep, granitic basement can be demonstrated, the electric power generation potential would be considerable. The objective of this study is to look at the specific geographical region extending from northeast to southeast of the village of Litchfield to the Nevada border as a target area for the first commercial application of Hot Dry Rock reservoir stimulation techniques. The ultimate goal is to provide background information that could lead to the creation of a commercial-scale, engineered geothermal reservoir in granitic basement rock of low permeability.

Brown, D.W.

1996-10-01T23:59:59.000Z

163

LASL Hot Dry Rock Geothermal Project. Progress report, July 1, 1975--June 30, 1976  

DOE Green Energy (OSTI)

Successful drilling into hard crystalline rock was accomplished to depths of about 3 km. Hydraulic fractures in the crystalline rock with radii as large as 150 m were produced. Values of in situ permeability of the Fenton Hill granite were measured. Directional drilling at depths of up to 3 km was accomplished. At least 90 to 95 percent of water injected into fractured regions was recovered. A connection was established between two deep boreholes through a fractured region of hot granite for the first time. Instruments were developed to operate for several hours under the downhole conditions. The compressional and shear components of seismic signals produced by fracture extension and inflation were detected downholes. Acoustic ranging has generally identified the relative positions of two boreholes at several depths. Self-potential and induced potential techniques have determined vertical fracture lengths at the borehole. Pressure-flow and fluid residence time distribution studies have measured properties of the downhole system. Core sample studies have provided physical and chemical data. Techniques were developed to examine reservoir performance. A geothermal power-production model was formulated. (MHR)

Blair, A.G.; Tester, J.W.; Mortensen, J.J. (comps.)

1976-10-01T23:59:59.000Z

164

Hot dry rock geothermal potential of Roosevelt Hot Springs area: review of data and recommendations  

DOE Green Energy (OSTI)

The Roosevelt Hot Springs area in west-central Utah possesses several features indicating potential for hot dry rock (HDR) geothermal development. The area is characterized by extensional tectonics and a high regional heat flow of greater than 105 mW/m/sup 2/. The presence of silicic volcanic rocks as young as 0.5 to 0.8 Myr and totaling 14 km/sup 3/ in volume indicates underlying magma reservoirs may be the heat source for the thermal anomaly. Several hot dry wells have been drilled on the periphery of the geothermal field. Information obtained on three of these deep wells shows that they have thermal gradients of 55 to 60/sup 0/C/km and bottom in impermeable Tertiary granitic and Precambrian gneissic units. The Tertiary granite is the preferred HDR reservoir rock because Precambrian gneissic rocks possess a well-developed banded foliation, making fracture control over the reservoir more difficult. Based on a fairly conservative estimate of 160 km/sup 2/ for the thermal anomaly present at Roosevelt Hot Springs, the area designated favorable for HDR geothermal exploration may be on the order of seven times or more than the hydrogeothermal area currently under development.

East, J.

1981-05-01T23:59:59.000Z

165

Small geothermal electric systems for remote powering  

DOE Green Energy (OSTI)

This report describes conditions and costs at which quite small (100 to 1,000 kilowatt) geothermal systems could be used for off-grid powering at remote locations. This is a first step in a larger process of determining locations and conditions at which markets for such systems could be developed. The results suggest that small geothermal systems offer substantial economic and environmental advantages for powering off-grid towns and villages. Geothermal power is most likely to be economic if the system size is 300 kW or greater, down to reservoir temperatures of 100{degree}C. For system sizes smaller than 300 kW, the economics can be favorable if the reservoir temperature is about 120{degree}C or above. Important markets include sites remote from grids in many developing and developed countries. Estimates of geothermal resources in many developing countries are shown.

Entingh, Daniel J.; Easwaran, Eyob.; McLarty, Lynn

1994-08-08T23:59:59.000Z

166

Definition: Enhanced Geothermal Systems | Open Energy Information  

Open Energy Info (EERE)

Definition Also Known As EGS, Engineered Geothermal Systems References http:www1.eere.energy.govgeothermalenhancedsystems.html Ret LikeLike UnlikeLike You like this.Sign...

167

Engineering methods for predicting productivity and longevity of hot-dry-rock geothermal reservoir in the presence of thermal cracks. Technical completion report  

DOE Green Energy (OSTI)

Additional heat extraction from geothermal energy reservioirs depends on the feasibility to extend the main, hydraulic fracture through secondary thermal cracks of the adjacent hot rock. When the main, hydraulic fracture is cooled sufficiently, these secondary thermal cracks are produced normal to the main fracture surface. As such, both the heat transfer surface area and heat energy available to the fluid circulating through the main, hydraulic fracture system increase. Methods for predicting the productivity and longevity of a geothermal reservoir were developed. A question is whether a significant long-term enhancement of the heat extraction process is achieved due to these secondary thermal cracks. In short, the objectives of this investigation are to study how the main, hydraulic fracture can be extended through these secondary thermal cracks of the rock, and to develop methods for predicting the productivity and longevity of a geothermal reservoir.

Hsu, Y.C.; Lu, Y.M.; Ju, F.D.; Dhingra, K.C.; Lu, Y.M.; Ju, F.D.; Dhingra, K.C.

1978-01-01T23:59:59.000Z

168

Seismological investigation of crack formation in hydraulic rock fracturing experiments and in natural geothermal environments. Progress report, September 1, 1978-August 31, 1979  

DOE Green Energy (OSTI)

An interpretation theory based on the fluid-filled crack model of geothermal systems is being developed and tested against a variety of data from various geothermal areas. Progress is reported on the following subjects: (1) analysis and interpretation of seismic data obtained from the bore holes at the LASL Hot Dry Rock geothermal site. (2) Collection, analysis and interpretation of data on deep volcanic tremors at the USGS Hawaii Volcano Observatory. (3) Development of a new method for determining seismic attenuation at frequencies higher than 1HZ, and initiation of a cooperative work with Mexican seismologists on the attenuation measurements at various geothermal areas in Baja, California using the method. (4) Installation of 3-component digital event-recorders at four stations in the Newberry Peak volcano, Oregon. (5) Developing a computer program for calculating seismic motion generated by the vibration of fluid-filled crack in a layered medium.

Aki, K.

1979-09-01T23:59:59.000Z

169

Seismic reconnaissance of the Los Alamos Scientific Laboratory's Dry Hot Rock Geothermal Project area  

DOE Green Energy (OSTI)

Active seismic methods using high-explosive sources and nondestructive energy sources were used to determine seismic velocities, signal detectability, and subsurface geologic structure in the vicinity of the Los Alamos Scientific Laboratory's (LASL) Dry Hot Rock Geothermal Project area. Positions of several faults have been determined. A synthetic seismogram has been created that shows good agreement with recorded reflection records taken near exploratory borehole GT-2.

Kintzinger, P.R.; West, F.G.

1976-07-01T23:59:59.000Z

170

Energy from hot dry rock  

DOE Green Energy (OSTI)

The Hot Dry Rock Geothermal Energy Program is described. The system, operation, results, development program, environmental implications, resource, economics, and future plans are discussed. (MHR)

Hendron, R.H.

1979-01-01T23:59:59.000Z

171

Evaluation of geothermal cooling systems for Arizona  

DOE Green Energy (OSTI)

Arizona consumes nearly 50 percent more electricity during the peak summer season of May through part of October, due to the high cooling load met by electrical-driven air conditioning units. This study evaluates two geothermal-driven cooling systems that consume less electricity, namely, absorption cooling and heat pumps. Adsorption cooling requires a geothermal resource above 105{sup 0}C (220{sup 0}F) in order to operate at a reasonable efficiency and capacity. Geothermal resources at these temperatures or above are believed existing in the Phoenix and Tucson areas, but at such depths that geothermal-driven absorption systems have high capital investments. Such capital investments are uneconomical when paid out over only five months of operation each year, but become economical when cascaded with other geothermal uses. There may be other regions of the state, where geothermal resources exist at 105{sup 0}C (220{sup 0}F) or higher at much less depth, such as the Casa Grande/Coolidge or Hyder areas, which might be attractive locations for future plants of the high-technology industries. Geothermal assisted heat pumps have been shown in this study to be economical for nearly all areas of Arizona. They are more economical and reliable than air-to-air heat pumps. Such systems in Arizona depend upon a low-temperature geothermal resource in the narrow range of 15.5 to 26.6{sup 0}C (60 to 80{sup 0}F), and are widely available in Arizona. The state has over 3000 known (existing) thermal wells, out of a total of about 30,000 irrigation wells.

White, D.H.; Goldstone, L.A.

1982-08-01T23:59:59.000Z

172

Near-Surface CO2 Monitoring And Analysis To Detect Hidden Geothermal Systems  

E-Print Network (OSTI)

dioxide flux at the Dixie Valley geothermal field, Nevada;volcanic system, USA Dixie Valley Geothermal Field, USAProvince system like the Dixie Valley (Nevada) geothermal

Lewicki, Jennifer L.; Oldenburg, Curtis M.

2005-01-01T23:59:59.000Z

173

Seal/lubricant systems for geothermal drilling equipment  

DOE Green Energy (OSTI)

The development and testing of seals and lubricants for journal-type roller-cone rock bits for drilling into geothermal reservoirs at temperatures over 260/sup 0/C (500/sup 0/F) are described. The conditions experienced by seals and lubricants subjected to geothermal drilling are reviewed along with the basic design requirements for roller-cone bit seals and journal bearing lubricants. Two unique test facilities are described: a seal test machine which simulates pressures, temperatures, and mechanical eccentricities, and a lubricant tester capable of evaluating load-bearing ability at temperature and pressure. Three candidate elastomeric compounds demonstrated 288/sup 0/C (550/sup 0/F) capability and several others demonstrated 260/sup 0/C (500/sup 0/F) or greater capability. Successful elastomeric seal candidates were proprietary compounds based on EPDM, Kalrez, and/or Viton polymers. Three mechanical seals for reservoir temperatures over 288/sup 0/C (550/sup 0/F) are presented. Lubricant screening tests on more than 50 products are summarized, and several newly developed lubricants which meet both the compatibility and lubrication requirements are described. Several seal/lubricant systems are recommended for laboratory or field geothermal drilling tests in roller-cone drill bits. The future availability of drill bits for geothermal use is discussed, as well as the potential spinoffs of the program findings for nongeothermal roller-cone bits.

Hendrickson, R.R.; Winzenried, R.W.

1980-07-01T23:59:59.000Z

174

Geothermal Heat Pump System for New Student Housing Geothermal...  

Open Energy Info (EERE)

Buildings Clean Energy Economy Coordinated Low Emissions Assistance Network Geothermal Incentives and Policies International Clean Energy Analysis Low Emission Development...

175

Geothermal Heat Pump System for Ice Arena Geothermal Project...  

Open Energy Info (EERE)

Buildings Clean Energy Economy Coordinated Low Emissions Assistance Network Geothermal Incentives and Policies International Clean Energy Analysis Low Emission Development...

176

Hot Dry Rock Geothermal Energy Development Program Annual Report Fiscal Year 1988  

DOE Green Energy (OSTI)

The complete list of HDR objectives is provided in Reference 10, and is tabulated below in Tables 1 and 2 for the reader's convenience. The primary, level 1, objective for HDR is ''to improve the technology to the point where electricity could be produced commercially from a substantial number of known HDR resource sites in a cost range of 5 to 8 cents/kWh by 1997''. A critically important milestone in attaining this cost target is the level II objective: ''Evaluate the performance of the Fenton Hill Phase II reservoir''. To appreciate the significance of this objective, a brief background is helpful. During the past 14 years the US DOE has invested $123 million to develop the technology required to make Hot Dry Rock geothermal energy commercially useful. The Governments of Japan and the Federal Republic of Germany have contributed an additional $32 million to the US program. The initial objectives of the program were met by the successful development and long-term operation of a heat-extraction loop in hydraulically-fractured hot dry rock. This Phase I reservoir produced pressurized hot water at temperatures and flow rates suitable for many commercial uses such as space heating and food processing. It operated for more than a year with no major problems or detectable environmental effect. With this accomplished and the technical feasibility of HDR energy systems demonstrated, the program undertook the more difficult task of developing a larger, deeper, hotter reservoir, called ''Phase II'', capable of supporting pilot-plant-scale operation of a commercial electricity-generating power plant. As described earlier in ''History of Research'', such a system was created and operated successfully in a preliminary 30-day flow test. However, to justify capital investment in HDR geothermal technology, industry now requires assurance that the reservoir can be operated for a long time without major problems or a significant decrease in the rate and quality of energy production. Industrial advisors to the HDR Program have concluded that, while a longer testing period would certainly be desirable, a successful and well-documented flow test of this high-temperature, Phase II reservoir lasting at least one year should convince industry that HDR geothermal energy merits their investment in its commercial development. This test is called the Long Term Flow Test (LTFT), and its completion will be a major milestone in attaining the Level 1 objective. However, before the LTFT could be initiated, well EE-2 had to be repaired, as also briefly described in the ''History of Research''. During this repair operation, superb progress was made toward satisfying the next most critically important Level II objective: Improve the Performance of HDR Drilling and Completion Technology. During the repair of EE-2, Los Alamos sidetracked by drilling out of the damaged well at 2.96 km (9700 ft), and then completed drilling a new-wellbore (EE-2A) to a total depth of 3.78 km (12,360 ft). As a consequence of this drilling experience, Los Alamos believes that if the original wells were redrilled today their combined cost would be only $8 million rather than the $18.8 million actually spent (a 60% cost saving). Further details, particularly of the completion of the well, can be found in the major section, ACCOMPLISHMENTS, but it can be seen that the second, Level II objective is already nearing attainment.

Dash, Zora V.; Murphy, Hugh D.; Smith, Morton C.

1988-01-01T23:59:59.000Z

177

Development of geothermal-well-completion systems. Final report  

DOE Green Energy (OSTI)

Results of a three year study concerning the completion of geothermal wells, specifically cementing, are reported. The research involved some specific tasks: (1) determination of properties an adequate geothermal well cement must possess; (2) thorough evaluation of current high temperature oilwell cementing technology in a geothermal context; (3) basic research concerning the chemical and physical behavior of cements in a geothermal environment; (4) recommendation of specific cement systems suitable for use in a geothermal well.

Nelson, E.B.

1979-01-01T23:59:59.000Z

178

Heat flow and hot dry rock geothermal resources of the Clearlake Region, northern California  

DOE Green Energy (OSTI)

The Geysers-Clear Lake geothermal anomaly is an area of high heat flow in northern California. The anomaly is caused by abnormally high heat flows generated by asthenospheric uplift and basaltic magmatic underplating at a slabless window created by passage of the Mendocino Triple Junction. The Clear Lake volcanic field is underlain by magmatic igneous bodies in the form of a stack of sill-form intrusions with silicic bodies generally at the top and basic magmas at the bottom. The tabular shape and wide areal extent of the heat sources results in linear temperature gradients and near-horizontal isotherms in a broad region at the center of the geothermal anomaly. The Hot Dry Rock (HDR) portion of The Geysers-Clear Lake geothermal field is that part of the geothermal anomaly that is external to the steamfield, bounded by geothermal gradients of 167 mW/m2 (4 heat flow units-hfu) and 335 mW/m2 (8 hfu). The HDR resources, to a depth of 5 km, were estimated by piece-wise linear summation based on a sketch map of the heat flow. Approximately, the geothermal {open_quotes}accessible resource base{close_quotes} (Qa) is 1.68E+21 J; the {open_quotes}HDR resource base{close_quotes} (Qha) is 1.39E+21 J; and the {open_quotes}HDR power production resource{close_quotes} (Qhp) is 1.01E+21 J. The HDR power production resource (Qhp) is equivalent to 2.78E+ 11 Mwht (megawatt hours thermal), or 1.72E+11 bbls of oil.

Burns, K.L.

1996-08-01T23:59:59.000Z

179

The Role of Boron-Chloride and Noble Gas Isotope Ratios in TVZ Geothermal Systems  

DOE Green Energy (OSTI)

The model of the geothermal system in which deep circulating groundwater containing noble gases, at air saturated water concentrations, mixes with hot fluids of mantle origin at depth, is extended to include the effect of interaction of the ascending fluid with both solid and gaseous phases of basement (or other) rocks en route to the surface. It is demonstrated that this interaction is responsible for most of the CO{sub 2} in the Taupo Volcanic Zone (TVZ) geothermal systems. It is proposed that the modeling of this interaction might be accomplished by techniques similar to those used for the understanding of the oxygen isotope shift found in geothermal systems. The water rock interaction experiments of Ellis and Mahon (1964, 1967) provides some data on the kinetic rates for B and Cl dissolution from rocks likely to be encountered in the geothermal system, but further information on the behavior of B may be needed. If these problems can be overcome this modeling technique has promise for the estimation of the recharge of geothermal systems and hence the sustainability of these systems.

Hulston, J.R.

1995-01-01T23:59:59.000Z

180

Hot dry rock energy: Hot dry rock geothermal development program. Progress report. Fiscal year 1993  

DOE Green Energy (OSTI)

Extended flow testing at the Fenton Hill Hot Dry Rock (HDR) test facility concluded in Fiscal Year 1993 with the completion of Phase 2 of the long-term flow test (LTFT) program. As is reported in detail in this report, the second phase of the LTFT, although only 55 days in duration, confirmed in every way the encouraging test results of the 112-day Phase I LTFT carried out in Fiscal Year 1992. Interim flow testing was conducted early in FY 1993 during the period between the two LTFT segments. In addition, two brief tests involving operation of the reservoir on a cyclic schedule were run at the end of the Phase 2 LTFT. These interim and cyclic tests provided an opportunity to conduct evaluations and field demonstrations of several reservoir engineering concepts that can now be applied to significantly increase the productivity of HDR systems. The Fenton Hill HDR test facility was shut down and brought into standby status during the last part of FY 1993. Unfortunately, the world`s largest, deepest, and most productive HDR reservoir has gone essentially unused since that time.

Salazar, J.; Brown, M. [eds.

1995-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "rock geothermal systems" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Energy analysis of geothermal-electric systems  

DOE Green Energy (OSTI)

Standard energy analysis was applied to 4 types of geothermal-electric technologies: liquid dominated, hot dry rock, geopressure, and vapor dominated. It was found that all are net energy producers. Expected uncertainties are not large enough to threaten this conclusion. Vapor dominated, the only technology in current commercial use to produce electricity in the US, has the highest energy ratio (13 +- 4). These results for energy ratio are equal to or less than some from other workers. In the case of liquid dominated, environmental control technology has a considerable energy requirement.

Herendeen, R.A.; Plant, R.

1979-12-01T23:59:59.000Z

182

Temporary Cementitious Sealers in Enhanced Geothermal Systems  

DOE Green Energy (OSTI)

Unlike conventional hydrothennal geothermal technology that utilizes hot water as the energy conversion resources tapped from natural hydrothermal reservoir located at {approx}10 km below the ground surface, Enhanced Geothermal System (EGS) must create a hydrothermal reservoir in a hot rock stratum at temperatures {ge}200 C, present in {approx}5 km deep underground by employing hydraulic fracturing. This is the process of initiating and propagating a fracture as well as opening pre-existing fractures in a rock layer. In this operation, a considerable attention is paid to the pre-existing fractures and pressure-generated ones made in the underground foundation during drilling and logging. These fractures in terms of lost circulation zones often cause the wastage of a substantial amount of the circulated water-based drilling fluid or mud. Thus, such lost circulation zones must be plugged by sealing materials, so that the drilling operation can resume and continue. Next, one important consideration is the fact that the sealers must be disintegrated by highly pressured water to reopen the plugged fractures and to promote the propagation of reopened fractures. In response to this need, the objective of this phase I project in FYs 2009-2011 was to develop temporary cementitious fracture sealing materials possessing self-degradable properties generating when {ge} 200 C-heated scalers came in contact with water. At BNL, we formulated two types of non-Portland cementitious systems using inexpensive industrial by-products with pozzolanic properties, such as granulated blast-furnace slag from the steel industries, and fly ashes from coal-combustion power plants. These byproducts were activated by sodium silicate to initiate their pozzolanic reactions, and to create a cemetitious structure. One developed system was sodium silicate alkali-activated slag/Class C fly ash (AASC); the other was sodium silicate alkali-activated slag/Class F fly ash (AASF) as the binder of temper-try sealers. Two specific additives without sodium silicate as alkaline additive were developed in this project: One additive was the sodium carboxymethyl cellulose (CMC) as self-degradation promoting additive; the other was the hard-burned magnesium oxide (MgO) made from calcinating at 1,000-1,500 C as an expansive additive. The AASC and AASF cementitious sealers made by incorporating an appropriate amount of these additives met the following six criteria: 1) One dry mix component product; 2) plastic viscosity, 20 to 70 cp at 300 rpm; 3) maintenance of pumpability for at least 1 hour at 85 C; 4) compressive strength >2000 psi; 5) self-degradable by injection with water at a certain pressure; and 6) expandable and swelling properties; {ge}0.5% of total volume of the sealer.

Sugama T.; Pyatina, T.; Butcher, T.; Brothers, L.; Bour, D.

2011-12-31T23:59:59.000Z

183

Geographic Information System At International Geothermal Area, Indonesia  

Open Energy Info (EERE)

International Geothermal Area, Indonesia International Geothermal Area, Indonesia (Nash, Et Al., 2002) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Geographic Information System At International Geothermal Area Indonesia (Nash, Et Al., 2002) Exploration Activity Details Location International Geothermal Area Indonesia Exploration Technique Geographic Information System Activity Date Usefulness not indicated DOE-funding Unknown Notes GIs also facilitates grid data (raster) analysis and visualization. For example, a raster GIs layer, derived from an enhanced Landsat 7 Thematic Mapper (TM) image of the Karaha-Telaga Bodas area, Indonesia, is shown in Figure 2. References Gregory D. Nash, Christopher Kesler, Michael C. Adam (2002) Geographic Information Systems- Tools For Geotherm Exploration, Tracers

184

Temporal changes in noble gas compositions within the Aidlin sector ofThe Geysers geothermal system  

E-Print Network (OSTI)

felsite unit), Geysers geothermal field, California: a 40California A summary. Geothermal Resources Councilsystematics of a continental geothermal system: results from

Dobson, Patrick; Sonnenthal, Eric; Kennedy, Mack; van Soest, Thijs; Lewicki, Jennifer

2006-01-01T23:59:59.000Z

185

Geochemical characterization of geothermal systems in the Great...  

Open Energy Info (EERE)

insights into the possible contributions of geothermal systems to groundwater chemistry and development of mitigation strategies for attendant environmental issues....

186

The Clearlake Hot Dry Rock geothermal project: Institutional policies, administrative issues, and technical tasks  

DOE Green Energy (OSTI)

The Clearlake Project is a three-party collaboration between the California Energy Commission, City of Clearlake, and Los Alamos National Laboratory. It aims to develop a deep hot, dry geothermal resource under the city. The project is funded by the Commission, and administered by the City. Technical operations are conducted by Laboratory staff and resources seconded from the Hot Dry Rock program. In addition to the normal geothermal exploration problems of predicting geological and geophysical properties of the subsurface, there are uncertainties as to what further material and environmental parameters are relevant, and how they might be measured. In addition to technical factors, policy objectives are an influence in choosing the most appropriate development scenario. 11 refs., 4 figs.

Burns, K.L.

1991-01-01T23:59:59.000Z

187

Fracture Surface Area Effects on Fluid Extraction and the Electrical Resistivity of Geothermal Reservoir Rocks  

DOE Green Energy (OSTI)

Laboratory measurements of the electrical resistivity of fractured analogue geothermal reservoir rocks were performed to investigate the resistivity contrast caused by active boiling and to determine the effects of variable fracture dimensions and surface area on water extraction. Experiments were performed at confining pressures up to 10 h4Pa (100 bars) and temperatures to 170 C. Fractured samples show a larger resistivity change at the onset of boiling than intact samples. Monitoring the resistivity of fractured samples as they equilibrate to imposed pressure and temperature conditions provides an estimate of fluid migration into and out of the matrix. Measurements presented are an important step toward using field electrical methods to quantitatively search for fractures, infer saturation, and track fluid migration in geothermal reservoirs.

Roberts, J J; Detwiler, R L; Ralph, W; Bonner, B

2002-05-09T23:59:59.000Z

188

Geothermal Technologies | Open Energy Information  

Open Energy Info (EERE)

Geothermal Technologies Geothermal Technologies (Redirected from Geothermal Conversion Technologies) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Print PDF Geothermal Technologies Geothermal energy can be utilized for electricity or heating in more than one way. Regardless of the energy conversion, geothermal energy requires heat(in the form of rock), water, and flow; and every resources will have different values for each. Some resources have very high temperature rock with high porosity (allowing for flow) but little to know water (see Enhanced Geothermal Systems (EGS). Some resources have plenty of water, great flow, but the temperatures are not very high which are commonly used for direct use. Any combination of those 3 things can be found in nature, and for that reason there are different classifications of geothermal

189

Development of Exploration Methods for Engineered Geothermal...  

Open Energy Info (EERE)

for Engineered Geothermal Systems (EGS). Awardees (Company Institution) AltaRock Energy, Inc. Awardee Website http:www.altarockenergy.com Partner 1 University of Nevada at...

190

36Cl/Cl ratios in geothermal systems: preliminary measurements from the Coso Field  

DOE Green Energy (OSTI)

The {sub 36}Cl/Cl isotopic composition of chlorine in geothermal systems can be a useful diagnostic tool in characterizing hydrologic structure, in determining the origins and age of waters within the systems, and in differentiating the sources of chlorine (and other solutes) in the thermal waters. The {sub 36}Cl/Cl values for several geothermal water samples and reservoir host rock samples from the Coso, California geothermal field have been measured for these purposes. The results indicate that most of the chlorine is not derived from the dominant granitoid that host the geothermal system. If the chlorine was originally input into the Coso subsurface through meteoric recharge, that input occurred at least 1-1.25 million years ago. The results suggest that the thermal waters could be connate waters derived from sedimentary formations, presumably underlying and adjacent top the granitic rocks, which have recently migrated into the host rocks. Alternatively, most of the chlorine but not the water, may have recently input into the system from magmatic sources. In either case, the results indicate that most of the chlorine in the thermal waters has existed within the granitoid host rocks for no more than about 100,00-200,00 years. this residence time for the chlorine is similar to residence times suggested by other researchers for chlorine in deep groundwaters of the Mono Basin north of the Coso field.

Nimz, G.J.; Moore, J.N.; Kasameyer, P.W.

1997-07-01T23:59:59.000Z

191

Baseline System Costs for 50.0 MW Enhanced Geothermal System...  

Open Energy Info (EERE)

Baseline System Costs for 50.0 MW Enhanced Geothermal System -- A Function of: Working Fluid, Technology, and Location Geothermal Project Jump to: navigation, search Last modified...

192

Electrical properties of geothermal reservoir rocks as indicators of porosity distribution  

DOE Green Energy (OSTI)

Measurements of the electrical resistivity of metashales from borehole SB-15-D in The Geyers geothermal area at a variety of conditions in the laboratory provide information regarding the distribution of porosity as interpreted from observations of boiling as downstream pore pressure. Electrical resistivity measurements on core,with and without pore pressure control, to confining pressures up to 100 bars and temperatures between 20 and 150 C allow assessment of the separate and combined effects of confining pressure, pore pressure and temperature for rocks from this borehole.

Duba, A.; Roberts, J.; Bonner, B.

1997-03-01T23:59:59.000Z

193

Induced seismicity associated with enhanced geothermal system  

Science Conference Proceedings (OSTI)

Enhanced Geothermal Systems (EGS) offer the potential to significantly add to the world energy inventory. As with any development of new technology, some aspects of the technology has been accepted by the general public, but some have not yet been accepted and await further clarification before such acceptance is possible. One of the issues associated with EGS is the role of microseismicity during the creation of the underground reservoir and the subsequent extraction of the energy. The primary objectives of this white paper are to present an up-to-date review of the state of knowledge about induced seismicity during the creation and operation of enhanced geothermal systems, and to point out the gaps in knowledge that if addressed will allow an improved understanding of the mechanisms generating the events as well as serve as a basis to develop successful protocols for monitoring and addressing community issues associated with such induced seismicity. The information was collected though literature searches as well as convening three workshops to gather information from a wide audience. Although microseismicity has been associated with the development of production and injection operations in a variety of geothermal regions, there have been no or few adverse physical effects on the operations or on surrounding communities. Still, there is public concern over the possible amount and magnitude of the seismicity associated with current and future EGS operations. It is pointed out that microseismicity has been successfully dealt with in a variety of non-geothermal as well as geothermal environments. Several case histories are also presented to illustrate a variety of technical and public acceptance issues. It is concluded that EGS Induced seismicity need not pose any threat to the development of geothermal resources if community issues are properly handled. In fact, induced seismicity provides benefits because it can be used as a monitoring tool to understand the effectiveness of the EGS operations and shed light on the mechanics of the reservoir.

Majer, Ernest; Majer, Ernest L.; Baria, Roy; Stark, Mitch; Oates, Stephen; Bommer, Julian; Smith, Bill; Asanuma, Hiroshi

2006-09-26T23:59:59.000Z

194

Geothermal Progress Monitor. System status and operational experience  

DOE Green Energy (OSTI)

The Geothermal Progress Monitor (GPM) system was designed and implemented by MITRE for DOE's Division of Geothermal Energy (now the Division of Geothermal and Hydropower Technologies). This report summarizes MITRE's operational experience with the system during fiscal year 1983 and provides a qualitative assessment of its data sources.

Gerstein, R.E.; Medville, D.M.

1983-11-01T23:59:59.000Z

195

FY 1996 Summary of Hot Dry Rock Geothermal Power Project  

DOE Green Energy (OSTI)

The report describes progress and status of the HDR project at Hijiori. The year was notable for a flow enhancement test of a system with two production wells in operation. Other items include a geochemical survey, reinterpretation of acoustic emission data from 1988 through 1995, borehole measurements to find intersections with fractures, a geological survey, preparation for modeling fractures, improvements in crack simulation in a reservoir analysis model, and environmental survey work. (DJE 2005)

None

1996-12-31T23:59:59.000Z

196

The US Hot Dry Rock Geothermal Energy Development Program  

DOE Green Energy (OSTI)

Recent accomplishments of the program are highlighted by a successful limited term flow test of the Phase 2 reservoir at the Fenton Hill site near Los Alamos. This reservoir connection was established by sidetracking one of the deep wells into hydraulically fractured areas, identified by microseismic data after original fracture attempts failed to connect the two wells. Hydraulic communication was improved by supplemental fracturing. Preliminary testing indicated a reservoir with fracture volume and heat production area surpassing the values from the earlier Phase 1 reservoir. Following completion of the downhole reservoir system, preparations were made for a reservoir-energy-extraction test. This Initial Closed Loop Flow Test (ICFT) was needed to obtain operating characteristics for planning a much longer test for thorough reservoir evaluation. The 30-day ICFT succeeded with final production of about 10 MWt at 192/sup 0/C, while injecting 285 gpm at 4600 psi and producing 206 gpm at 500 psi. The water loss rate and flow impedance were high, 27% and 18 psi/gpm respectively, but were declining. Radioactive tracer tests indicated reservoir volume growth during the experiment which was continuously monitored for acoustic or microseismic activity. Following the flow test, experiments were continued for several months during the venting process. Preparations are now underway for the Long Term Flow Test (LTFT). To understand as much as possible about the Phase 2 reservoir and to demonstrate the commercial feasibility of energy from HDR reservoirs, a flow test of approximately one year's duration is deemed necessary. Part of the preparation for the LTFT is the workover and repair of the production well and the installation of a competent overall flow loop and energy exchange system. 7 refs., 5 figs.

Franke, P.R.

1987-01-01T23:59:59.000Z

197

Hot dry rock geothermal energy development program. A progress report  

DOE Green Energy (OSTI)

Since the enlargement of the research reservoir was effected, two extended heat-extraction runs have been made. Run Segment 4 was conducted during October and November of 1979 for a total operating duration of 551 hours. The thermal drawdown data indicated that the effective heat-transfer area had been increased by not less than a factor of 6. The second test, Run Segment 5, began near the end of February 1980, and concluded on 16 December 1980. The enlargement of the reservoir is confirmed by the very gradual thermal drawdown, and the effective heat-transfer area of the research reservoir is now believed to be of the order of 50,000 m/sup 2/. To date, over 20 million kilowatt-hours of thermal energy have been extracted from the Fenton Hill research reservoir at Power Levels ranging from 2.3 to 5.0 MW/sub t/. Recently, a small on-line electric generation experiment was added as part of Run Segment 5. In the larger engineering system, the injection well (EE-2) is now complete to a depth of 4450 m with a bottom-hole temperature of 320 C and the production well (EE-3) is being drilled.

Franke, P.R.

1981-01-01T23:59:59.000Z

198

Geothermal energy systems plan for Boise City  

DOE Green Energy (OSTI)

This is a plan for development of a downtown Boise geothermal district space heating system incorporating legal, engineering, organizational, geological, and economic requirements. Topics covered include: resource characteristics, system design and feasibility, economic feasibility, legal overview, organizational alternatives, and conservation. Included in appendices are: property ownership patterns on the Boise Front, existing hot well data, legal briefs, environmental data, decision point communications, typical building heating system retrofit schematics, and background assumptions and data for cost summary. (MHR)

Not Available

1979-01-01T23:59:59.000Z

199

A combined heat transfer and quartz dissolution/deposition model for a hot dry rock geothermal reservoir  

DOE Green Energy (OSTI)

A kinetic model of silica transport has been coupled to a heat transfer model for a Hot Dry Rock (HDR) geothermal reservoir to examine the effect of silica rock-water interactions on fracture aperture and permeability. The model accounts for both the dissolution and deposition of silica. Zones of local dissolution and deposition were predicted, but their effect on aperture and permeability were fairly small for all cases studied. Initial rock temperature, reservoir size, and the ratio of rock surface area to fluid volume have the largest effect on the magnitude of silica mass transferred between the liquid and solid phases. 13 refs., 6 figs.

Robinson, B.A.; Pendergrass, J.

1989-01-01T23:59:59.000Z

200

Geothermal Resource Analysis and Structure of Basin and Range Systems, Especially Dixie Valley Geothermal Field, Nevada  

DOE Green Energy (OSTI)

Publish new thermal and drill data from the Dizie Valley Geothermal Field that affect evaluation of Basin and Range Geothermal Resources in a very major and positive way. Completed new geophysical surveys of Dizie Valley including gravity and aeromagnetics and integrated the geophysical, seismic, geological and drilling data at Dizie Valley into local and regional geologic models. Developed natural state mass and energy transport fluid flow models of generic Basin and Range systems based on Dizie Valley data that help to understand the nature of large scale constraints on the location and characteristics of the geothermal systems. Documented a relation between natural heat loss for geothermal and electrical power production potential and determined heat flow for 27 different geothermal systems. Prepared data set for generation of a new geothermal map of North American including industry data totaling over 25,000 points in the US alone.

David Blackwell; Kenneth Wisian; Maria Richards; Mark Leidig; Richard Smith; Jason McKenna

2003-08-14T23:59:59.000Z

Note: This page contains sample records for the topic "rock geothermal systems" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Hot dry rock geothermal energy for U.S. electric utilities. Draft final report  

DOE Green Energy (OSTI)

In order to bring an electric utility component into the study of hot dry rock geothermal energy called for in the Energy Policy Act of 1992 (EPAct), EPRI organized a one-day conference in Philadelphia on January 14,1993. The conference was planned as the first day of a two-day sequence, by coordinating with the U.S. Geological Survey (USGS) and the U.S. Department of Energy (DOE). These two federal agencies were charged under EPAct with the development of a report on the potential for hot dry rock geothermal energy production in the US, especially the eastern US. The USGS was given lead responsibility for a report to be done in association with DOE. The EPRI conference emphasized first the status of technology development and testing in the U.S. and abroad, i.e., in western Europe, Russia and Japan. The conference went on to address the extent of knowledge regarding the resource base in the US, especially in the eastern half of the country, and then to address some practical business aspects of organizing projects or industries that could bring these resources into use, either for thermal applications or for electric power generation.

Not Available

1993-06-01T23:59:59.000Z

202

Hot dry rock geothermal energy in the USA: Moving toward practical use  

DOE Green Energy (OSTI)

The technology for extracting geothermal energy from the vast hot dry rock (HDR) geothermal resource has been under development by the Los Alamos National Laboratory for about 25 years. In 1992--1993, an extensive flow-testing program was conducted at the Fenton Hill, New Mexico HDR Test Facility. During two segments of this test energy was produced at a rate of 4 thermal megawatts on a continuous basis for periods of 112 and 65 days, respectively. Surface and logging measurements showed no decline in the temperature of the water produced from the HDR reservoir during the flow testing. In fact, tracer evidence indicated that the circulating water was continually gaining access to additional hot rock as the testing proceeded. Water consumption was low and all other test data were positive. The encouraging results of the flow testing at Fenton Hill provided the incentive for the United States Department of Energy (USDOE) to solicit the interest of private industry in a jointly funded program to construct and operate a facility that would produce and sell energy derived from HDR resources. A number of organizations responded positively. On the basis of the interest expressed in these responses, the USDOE subsequently authorized the issuance of a formal solicitation to initiate the project.

Duchane, D.

1995-12-31T23:59:59.000Z

203

Materials selection guidelines for geothermal energy utilization systems  

DOE Green Energy (OSTI)

This manual includes geothermal fluid chemistry, corrosion test data, and materials operating experience. Systems using geothermal energy in El Salvador, Iceland, Italy, Japan, Mexico, New Zealand, and the United States are described. The manual provides materials selection guidelines for surface equipment of future geothermal energy systems. The key chemical species that are significant in determining corrosiveness of geothermal fluids are identified. The utilization modes of geothermal energy are defined as well as the various physical fluid parameters that affect corrosiveness. Both detailed and summarized results of materials performance tests and applicable operating experiences from forty sites throughout the world are presented. The application of various non-metal materials in geothermal environments are discussed. Included in appendices are: corrosion behavior of specific alloy classes in geothermal fluids, corrosion in seawater desalination plants, worldwide geothermal power production, DOE-sponsored utilization projects, plant availability, relative costs of alloys, and composition of alloys. (MHR)

Ellis, P.F. II; Conover, M.F.

1981-01-01T23:59:59.000Z

204

Progress in making hot dry rock geothermal energy a viable renewable energy resource for America in the 21. century  

DOE Green Energy (OSTI)

An enormous geothermal energy resource exists in the form of rock at depth that is hot but essentially dry. For more than two decades, work has been underway at the Los Alamos National Laboratory to develop and demonstrate the technology to transport the energy in hot dry rock (HDR) to the surface for practical use. During the 1980`s, the world`s largest, deepest and hottest HDR reservoir was created at the Fenton Hill HDR test facility in northern New Mexico. The reservoir is centered in rock at a temperature of about 460 F at a depth of about 11,400 ft. After mating the reservoir to a fully automated surface plant, heat was mined at Fenton Hill for a total period of almost a year in a series of flow tests conducted between 1992 and 1995. These tests addressed the major questions regarding the viability of long-term energy extraction from HDR. The steady-state flow tests at Fenton Hill showed that energy can be produced from an HDR reservoir on a routine basis and that there are no major technical obstacles to implementation of this heat mining technology. Additional brief special flow tests also demonstrated that the energy output from HDR systems can be rapidly increased in a controlled manner to meet sudden changes in power demand.

Duchane, D.V. [Los Alamos National Lab., NM (United States). Earth and Environmental Sciences Div.

1996-01-01T23:59:59.000Z

205

Reservoir modeling of the Phase II Hot Dry Rock System  

DOE Green Energy (OSTI)

The Phase II system has been created with a series of hydraulic fracturing experiments at the Fenton Hill Hot Dry Rock site. Experiment 2032, the largest of the fracturing operations, involved injecting 5.6 million gallons (21,200m/sup 3/) of water into wellbore EE-2 over the period December 6-9, 1983. The experiment has been modeled using geothermal simulator FEHM developed at Los Alamos National Laboratory. The modeling effort has produced strong evidence of a large highly fractured reservoir. Two long term heat extraction schemes for the reservoir are studied with the model.

Zyvoloski, G.

1984-01-01T23:59:59.000Z

206

Specific features of geothermal steam turbine control and emergency system  

SciTech Connect

There are significant construction as well as operational differences between geothermal and conventional steam turbines. These result in specific features associated with geothermal steam turbine control and emergency system. Several aspects of geothermal steam turbine control have been considered. Some proposals of geothermal steam turbine control have been presented. Among others the following operation modes have been considered: Driving turbine, driving well, turbine power and well steam pressure coupled control.

Domachowski, Z.; Gutierrez, A.

1986-01-01T23:59:59.000Z

207

Assessment of solar-geothermal hybrid system concepts  

SciTech Connect

Studies were conducted to assess the technical and economic merits and limitations of advanced solar-geothermal hybrid electric power plant concepts. Geothermal resource characteristics and technologies were reviewed to determine the best possible ways of combining solar and geothermal technologies into a hybrid operation. Potential hybrid system concepts are defined and their performance, resource usage, and economics are assessed relative to the individual solar and geothermal resource development techniques. Key results are presented.

Mathur, P.N.

1979-03-15T23:59:59.000Z

208

Development of Exploration Methods for Engineered Geothermal Systems  

Open Energy Info (EERE)

Exploration Methods for Engineered Geothermal Systems Exploration Methods for Engineered Geothermal Systems Through Integrated Geophysical, Geologic and Geochemical Interpretation the Seismic Analysis Component Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Paper: Development of Exploration Methods for Engineered Geothermal Systems Through Integrated Geophysical, Geologic and Geochemical Interpretation the Seismic Analysis Component Authors Ileana M. Tibuleac, Joe Iovenitti, David von Seggern, Jon Sainsbury, Glenn Biasi and John G. Anderson Conference Stanford Geothermal Conference; Stanford University; 2013 Published PROCEEDINGS, Thirty-Eighth Workshop on Geothermal Reservoir Engineering Stanford University;, 2013 DOI Not Provided Check for DOI availability: http://crossref.org

209

High Temperature 300C Directional Drilling System Geothermal...  

Open Energy Info (EERE)

Recovery Act: Enhanced Geothermal Systems Component Research and DevelopmentAnalysis Project Type Topic 2 Directional Drilling Systems Project Description The development plan...

210

Geothermal drilling technology update  

DOE Green Energy (OSTI)

Sandia National Laboratories conducts a comprehensive geothermal drilling research program for the US Department of Energy, Office of Geothermal Technologies. The program currently includes seven areas: lost circulation technology, hard-rock drill bit technology, high-temperature instrumentation, wireless data telemetry, slimhole drilling technology, Geothermal Drilling Organization (GDO) projects, and drilling systems studies. This paper describes the current status of the projects under way in each of these program areas.

Glowka, D.A.

1997-04-01T23:59:59.000Z

211

Behavior Of Rare Earth Element In Geothermal Systems, A New  

Open Energy Info (EERE)

Behavior Of Rare Earth Element In Geothermal Systems, A New Behavior Of Rare Earth Element In Geothermal Systems, A New Exploration-Exploitation Tool Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report: Behavior Of Rare Earth Element In Geothermal Systems, A New Exploration-Exploitation Tool Details Activities (32) Areas (17) Regions (0) Abstract: The goal of this four-year project was to provide a database by which to judge the utility of the rare earth elements (REE) in the exploration for and exploitation of geothermal fields in the United States. Geothermal fluids from hot springs and wells have been sampled from a number of locations, including: (1) the North Island of New Zealand (1 set of samples); (2) the Cascades of Oregon; (3) the Harney, Alvord Desert and Owyhee geothermal areas of Oregon; (4) the Dixie Valley and Beowawe fields

212

Report of the workshop on advanced geothermal drilling and completion systems  

DOE Green Energy (OSTI)

The discussions, conclusions, and recommendations of the Workshop on Advanced Geothermal Drilling and Completion Systems are summarized. The purpose of the workshop was to identify new drilling and completion systems that have the potential for significantly reducing the cost of geothermal wells, and to provide recommendations as to the research and development tasks that are required to develop these advanced systems. Participants in the workshop included representatives from private industry, universities, and government who were organized into four working groups as follows: Rock Drilling Technology, Surface Technology, Borehole Technology, and Directional Drilling Technology. The Panel on Rock Drilling Technology was charged with identifying advanced concepts for breaking rock that could result in instantaneous penetration rates three to five times higher than those of conventional rotary drilling. The Panel on Surface Technology discussed improvements in surface equipment and operating procedures that could contribute to reduced well costs. The Panel on Borehole Technology discussed problems associated with establishing and maintaining a stable borehole for the long-term production of geothermal wells. The Panel on Directional Drilling Technology addressed problems encountered in drilling deviated wells in geothermal reservoirs.

Varnado, S.G. (ed.)

1979-06-01T23:59:59.000Z

213

Hot dry rock geothermal energy: status of exploration and assessment. Report No. 1 of the hot dry rock assessment panel  

DOE Green Energy (OSTI)

The status of knowledge of attempts to utilize hot dry rock (HDR) geothermal energy is summarized. It contains (1) descriptions or case histories of the ERDA-funded projects at Marysville, MT, Fenton Hill, NM, and Coso Hot Springs, CA; (2) a review of the status of existing techniques available for exploration and delineation of HDR; (3) descriptions of other potential HDR sites; (4) definitions of the probable types of HDR resource localities; and (5) an estimate of the magnitude of the HDR resource base in the conterminous United States. The scope is limited to that part of HDR resource assessment related to the determination of the extent and character of HDR, with emphasis on the igneous-related type. It is estimated that approximately 74 Q (1 Q = 1,000 Quads) of heat is stored in these sites within the conterminous U.S. at depths less than 10 km and temperatures above 150/sup 0/C, the minimum for power generation. (Q = 10/sup 18/ BTU = 10/sup 21/J; the total U.S. consumption for 1972 was approximately 0.07 Q). Approximately 6300 Q are stored in the conduction-dominated parts of the crust in the western U.S. (23% of the total surface area), again at depths less than 10 km and temperatures above 150/sup 0/C. Nearly 10,000 Q are believed to be contained in crustal rocks underlying the entire conterminous U.S., at temperatures above 150/sup 0/C. The resource base is significantly larger for lower grade heat. (JGB)

Not Available

1977-06-01T23:59:59.000Z

214

Prediction of Scaling in Geothermal Systems  

Science Conference Proceedings (OSTI)

One of the main objectives of the DOE Geothermal Program is to improve the efficiency and reliability of geothermal operations so that this renewable form of energy can be integrated into the nation's energy system. Scale formation and other chemical problems associated with energy extraction from high temperature brines frequently inhibit the economical utilization of geothermal resources. In some cases, these chemical problems can be so severe that development of a site must be abandoned after considerable capital investment. The goal of our research efforts is to construct an accurate computer model for describing the chemical behavior of geothermal brines under a wide range of operating conditions. This technology will provide industry a cost-effective means of identifying scaling problems in production and reinjection wells as well as in surface equipment, and also devising and testing methods for well as other uses described in table (1) can contribute significantly to meeting the objectives of the Geothermal Program. The chemical model we have developed to date can simulate calcium carbonate scale formation and gas solubilities in concentrated brines containing sodium, potassium, calcium, chloride and sulfate ions as a function of temperature to 250 C and for variable partial pressure of CO{sub 2}. It can predict the solubility of other scale-forming minerals, such as amorphous silica, gypsum-anhydrite, halite and glasserite, as a function of brine composition to 250 C. The only required input for the model is the temperature, pressure and composition of the brine. Our modeling approach is based on semi-empirical thermodynamic descriptions of aqueous solutions. The model equations are parameterized by careful comparison to a variety of laboratory data. The ability of the resulting models to accurately predict the chemical behavior of even very concentrated high temperature brines is well demonstrated. This ability is an unusual feature of our models which is vital for applications to many important geothermal systems, such as those found in the Imperial Valley of California. In this report, the use of the present version of our model will be illustrated by an application to the prediction of the onset of two phase flow (breakout) in a brine confined by an external pressure. Calculations of this kind are important in assessing the production potential of a geothermal resource because the initiation of breakout in a well bore or power plant is usually simultaneous with the appearance of massive scale deposition. It is therefore necessary to predict breakout and also to assess the consequences of breakout in designing more efficient energy extraction processes. For the geothermal brine for which we have reliable composition and breakout data (East Mesa in California), the model gives results which are essentially identical to the measured values. Calculations also illustrate the importance of contributions of dissolved gases to the total pressure of the brines. Applications to other scale formation problems in Dixie Valley geothermal brines will also be discussed.

Weare, John H.; Moller, Nancy E.

1989-03-21T23:59:59.000Z

215

Numerical Modelling of Geothermal Systems a Short Introduction | Open  

Open Energy Info (EERE)

Numerical Modelling of Geothermal Systems a Short Introduction Numerical Modelling of Geothermal Systems a Short Introduction Jump to: navigation, search OpenEI Reference LibraryAdd to library General: Numerical Modelling of Geothermal Systems a Short Introduction Authors Mauro Cacace, Björn Onno Kaiser and Yvonne Cherubini Published Helmholtz Association, The date "N/A" was not understood.The date "N/A" was not understood. DOI Not Provided Check for DOI availability: http://crossref.org Online Internet link for Numerical Modelling of Geothermal Systems a Short Introduction Citation Mauro Cacace,Björn Onno Kaiser,Yvonne Cherubini. N/A. Numerical Modelling of Geothermal Systems a Short Introduction. N/A. Helmholtz Association. N/Ap. Retrieved from "http://en.openei.org/w/index.php?title=Numerical_Modelling_of_Geothermal_Systems_a_Short_Introduction&oldid=688986"

216

Ball State building massive geothermal system | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Ball State building massive geothermal system Ball State building massive geothermal system Ball State building massive geothermal system March 19, 2010 - 5:47pm Addthis Workers drill boreholes for a geothermal heating and cooling system at Ball State University’s campus in Muncie, Ind. | Photo courtesy of Ball State University Workers drill boreholes for a geothermal heating and cooling system at Ball State University's campus in Muncie, Ind. | Photo courtesy of Ball State University Paul Lester Communications Specialist for the Office of Energy Efficiency and Renewable Energy Ball State University is building America's largest ground source district geothermal heating and cooling system. The new operation will save the school millions of dollars, slash greenhouse gases and create jobs. The project will also "expand how America will define the use of

217

Ball State building massive geothermal system | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Ball State building massive geothermal system Ball State building massive geothermal system Ball State building massive geothermal system March 19, 2010 - 5:47pm Addthis Workers drill boreholes for a geothermal heating and cooling system at Ball State University’s campus in Muncie, Ind. | Photo courtesy of Ball State University Workers drill boreholes for a geothermal heating and cooling system at Ball State University's campus in Muncie, Ind. | Photo courtesy of Ball State University Paul Lester Communications Specialist, Office of Energy Efficiency and Renewable Energy Ball State University is building America's largest ground source district geothermal heating and cooling system. The new operation will save the school millions of dollars, slash greenhouse gases and create jobs. The project will also "expand how America will define the use of

218

Numerical Modeling Of Basin And Range Geothermal Systems | Open Energy  

Open Energy Info (EERE)

Numerical Modeling Of Basin And Range Geothermal Systems Numerical Modeling Of Basin And Range Geothermal Systems Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Numerical Modeling Of Basin And Range Geothermal Systems Details Activities (3) Areas (3) Regions (0) Abstract: Basic qualitative relationships for extensional geothermal systems that include structure, heat input, and permeability distribution have been established using numerical models. Extensional geothermal systems, as described in this paper, rely on deep circulation of groundwater rather than on cooling igneous bodies for heat, and rely on extensional fracture systems to provide permeable upflow paths. A series of steady-state, two-dimensional simulation models is used to evaluate the effect of permeability and structural variations on an idealized, generic

219

Geologic framework and hot dry rock geothermal potential of the Castle Dome area, Yuma County, Arizona  

DOE Green Energy (OSTI)

The Castle Dome Mountains and surrounding ranges constitute a voluminous pile of silicic volcanic rocks within the Basin and Range province of southwestern Arizona. Previously reported as Cretaceous and Quaternary in age, these volcanics all are of late Oligocene to early Miocene age as indicated by five new K-Ar dates. Reconnaissance field studies indicate that the volcanic section locally has undergone large rotations that contrast with the usual structural style of the Basin and Range and resemble the thin-skinned rotational tectonics documented for earlier, mid-Tertiary extensional deformation in ranges to the north and northeast. Significant geothermal potential of the Castle Dome area is suggested by a shallow depth to the Curie isotherm and by the apparent presence of a good electrical conductor at anomalously shallow depth in the crust. Warm wells exist in the area and Shearer (1979) reported a geothermal gradient of about 70/sup 0/C/km in a dry well near the center of the gravity low. Radiogenic heat production in the silicic batholith inferred above constitutes a reasonable candidate for a shallow regional heat source.

Gutmann, J.T.

1981-02-01T23:59:59.000Z

220

Geochemical characterization of geothermal systems in the Great Basin:  

Open Energy Info (EERE)

characterization of geothermal systems in the Great Basin: characterization of geothermal systems in the Great Basin: Implications for exploration, exploitation, and environmental issues Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Paper: Geochemical characterization of geothermal systems in the Great Basin: Implications for exploration, exploitation, and environmental issues Details Activities (0) Areas (0) Regions (0) Abstract: The objective of this ongoing project is the development of a representative geochemical database for a comprehensive range of elemental and isotopic parameters (i.e., beyond the typical data suite) for a range of geothermal systems in the Great Basin. Development of this database is one of the first steps in understanding the nature of geothermal systems in the Great Basin. Of particular importance in the Great Basin is utilizing

Note: This page contains sample records for the topic "rock geothermal systems" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Geographic Information Systems- Tools For Geotherm Exploration, Tracers  

Open Energy Info (EERE)

Systems- Tools For Geotherm Exploration, Tracers Systems- Tools For Geotherm Exploration, Tracers Data Analysis, And Enhanced Data Distribution, Visualization, And Management Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Paper: Geographic Information Systems- Tools For Geotherm Exploration, Tracers Data Analysis, And Enhanced Data Distribution, Visualization, And Management Details Activities (4) Areas (3) Regions (0) Abstract: Geographic information systems (GIS) are an underused resource that can help the geothermal industry in exploration, tracer analysis, infrastructure management, and the general distribution and use of data. GIS systems are highly customizable to specific user needs and can use entire corporate data sets through a visual interface. This paper briefly documents the use of GIS in specific examples of geothermal research at the

222

Stragegies to Detect Hidden Geothermal Systems Based on Monitoring and Analysis of CO2 in the Near-Surface Environment  

E-Print Network (OSTI)

dioxide flux at the Dixie Valley geothermal field, Nevada;volcanic system, USA Dixie Valley Geothermal Field, USAProvince system like the Dixie Valley (Nevada) geothermal

Lewicki, Jennifer L.; Oldenburg, Curtis M.

2008-01-01T23:59:59.000Z

223

Stragegies to Detect Hidden Geothermal Systems Based on Monitoring and Analysis of CO2 in the Near-Surface Environment  

E-Print Network (OSTI)

in volcanic and geothermal areas. Appl. Geochem. , 13, 5431977. Chemistry and Geothermal Systems. Academic Press, Newfor detecting hidden geothermal systems by near-surface gas

Lewicki, Jennifer L.; Oldenburg, Curtis M.

2008-01-01T23:59:59.000Z

224

Experience with the Development of Advanced Materials for Geothermal Systems  

Science Conference Proceedings (OSTI)

This chapter contains the following sections: Introduction, Advanced Cements, Materials Research and Development in Enhanced Geothermal Systems (EGS), Advanced Coatings, and Conclusions.

Sugama, T.; Butcher, T.; Ecker, L.

2011-01-01T23:59:59.000Z

225

36Cl/Cl ratios in geothermal systems- preliminary measurements...  

Open Energy Info (EERE)

(1) Areas (1) Regions (0) Abstract: The sub 36ClCl isotopic composition of chlorine in geothermal systems can be a useful diagnostic tool in characterizing hydrologic...

226

Identification of a New Blind Geothermal System with Hyperspectral...  

Open Energy Info (EERE)

a New Blind Geothermal System with Hyperspectral Remote Sensing and Shallow Temperature Measurements at Columbus Salt Marsh, Esmeralda County, Nevada Jump to: navigation, search...

227

Behavior of Rare Earth Elements in Geothermal Systems- A New...  

Open Energy Info (EERE)

2001 DOI Not Provided Check for DOI availability: http:crossref.org Online Internet link for Behavior of Rare Earth Elements in Geothermal Systems- A New Exploration...

228

Enthalpy restoration in geothermal energy processing system  

DOE Patents (OSTI)

A geothermal deep well energy extraction system is provided of the general type in which solute-bearing hot water is pumped to the earth's surface from a relatively low temperature geothermal source by transferring thermal energy from the hot water to a working fluid for driving a primary turbine-motor and a primary electrical generator at the earth's surface. The superheated expanded exhaust from the primary turbine motor is conducted to a bubble tank where it bubbles through a layer of sub-cooled working fluid that has been condensed. The superheat and latent heat from the expanded exhaust of the turbine transfers thermal energy to the sub-cooled condensate. The desuperheated exhaust is then conducted to the condenser where it is condensed and sub-cooled, whereupon it is conducted back to the bubble tank via a barometric storage tank. The novel condensing process of this invention makes it possible to exploit geothermal sources which might otherwise be non-exploitable.

Matthews, Hugh B. (Boylston, MA)

1983-01-01T23:59:59.000Z

229

EA-1893: Canby Cascaded Geothermal Development System, Canby, California |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

93: Canby Cascaded Geothermal Development System, Canby, 93: Canby Cascaded Geothermal Development System, Canby, California EA-1893: Canby Cascaded Geothermal Development System, Canby, California Summary This EA will evaluate the environmental impacts of a proposal by Modoc Contracting Company to use DOE grant funds to fulfill its plan to expand its reliance on geothermal resources by producing more hot water and using it to produce power as well as thermal energy. The goal of the project is to complete a cascaded geothermal system that generates green power for the local community, provides thermal energy to support greenhouse and aquaculture operation, provide sustainable thermal energy for residential units, and eliminate the existing geothermal discharge to a local river. NOTE: NOTE: This EA has been cancelled.

230

GEOLOGY AND HYDROTHERMAL ALTERATION OF THE RAFT RIVER GEOTHERMAL SYSTEM,  

Open Energy Info (EERE)

GEOLOGY AND HYDROTHERMAL ALTERATION OF THE RAFT RIVER GEOTHERMAL SYSTEM, GEOLOGY AND HYDROTHERMAL ALTERATION OF THE RAFT RIVER GEOTHERMAL SYSTEM, IDAHO Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: GEOLOGY AND HYDROTHERMAL ALTERATION OF THE RAFT RIVER GEOTHERMAL SYSTEM, IDAHO Details Activities (3) Areas (1) Regions (0) Abstract: The Raft River geothermal system is located in southern Idaho, near the Utah-Idaho state boarder in the Raft River Valley. The field, which is owned and operated by U.S. Geothermal, has been selected as an EGS demonstration site by the U. S. Department of Energy. This paper summarizes ongoing geologic and petrologic investigations being conducted in support of this project. The reservoir is developed in fractured Proterozoic schist and quartzite, and Archean quartz monzonite cut by younger diabase

231

Geothermal Resource Analysis and Structure of Basin and Range Systems,  

Open Energy Info (EERE)

Analysis and Structure of Basin and Range Systems, Analysis and Structure of Basin and Range Systems, Especially Dixie Valley Geothermal Field, Nevada Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Geothermal Resource Analysis and Structure of Basin and Range Systems, Especially Dixie Valley Geothermal Field, Nevada Authors David D. Blackwell, Kenneth W. Wisian, Maria C. Richards, Mark Leidig, Richard Smith and Jason McKenna Published U.S. Department of Energy, 2003 DOI Not Provided Check for DOI availability: http://crossref.org Online Internet link for Geothermal Resource Analysis and Structure of Basin and Range Systems, Especially Dixie Valley Geothermal Field, Nevada Citation David D. Blackwell,Kenneth W. Wisian,Maria C. Richards,Mark Leidig,Richard Smith,Jason McKenna. 2003. Geothermal Resource Analysis and Structure of

232

Residential space heating cost: geothermal vs conventional systems  

SciTech Connect

The operating characteristics and economies of several representative space heating systems are analyzed. The analysis techniques used may be applied to a larger variety of systems than considered herein, thereby making this document more useful to the residential developer, heating and ventilating contractor, or homeowner considering geothermal space heating. These analyses are based on the use of geothermal water at temperatures as low as 120/sup 0/F in forced air systems and 140/sup 0/F in baseboard convection and radiant floor panel systems. This investigation indicates the baseboard convection system is likely to be the most economical type of geothermal space heating system when geothermal water of at least 140/sup 0/F is available. Heat pumps utilizing water near 70/sup 0/F, with negligible water costs, are economically feasible and they are particularly attractive when space cooling is included in system designs. Generally, procurement and installation costs for similar geothermal and conventional space heating systems are about equal, so geothermal space heating is cost competitive when the unit cost of geothermal energy is less than or equal to the unit cost of conventional energy. Guides are provided for estimating the unit cost of geothermal energy for cases where a geothermal resource is known to exist but has not been developed for use in residential space heating.

Engen, I.A.

1978-02-01T23:59:59.000Z

233

Strategies for Detecting Hidden Geothermal Systems by Near-Surface Gas Monitoring  

E-Print Network (OSTI)

for Detection of Hidden Geothermal Systems Figure 7.4.for Detection of Hidden Geothermal Systems Figure 7.5.for Detection of Hidden Geothermal Systems Figure 7.6.

Lewicki, Jennifer L.; Oldenburg, Curtis M.

2004-01-01T23:59:59.000Z

234

Seismic Technology Adapted to Analyzing and Developing Geothermal...  

Open Energy Info (EERE)

Last modified on July 22, 2011. Project Title Seismic Technology Adapted to Analyzing and Developing Geothermal Systems Below Surface-Exposed High-Velocity Rocks Project Type ...

235

Geological and geophysical analysis of Coso Geothermal Exploration...  

Open Energy Info (EERE)

Only weak hydrothermal alteration was noted in these rocks. Drillhole surveys and drilling rate data indicate that the geothermal system is structurally controlled and that the...

236

Numerical models for the evaluation of geothermal systems  

DOE Green Energy (OSTI)

We have carried out detailed simulations of various fields in the USA (Bada, New Mexico; Heber, California); Mexico (Cerro Prieto); Iceland (Krafla); and Kenya (Olkaria). These simulation studies have illustrated the usefulness of numerical models for the overall evaluation of geothermal systems. The methodology for modeling the behavior of geothermal systems, different approaches to geothermal reservoir modeling and how they can be applied in comprehensive evaluation work are discussed.

Bodvarsson, G.S.; Pruess, K.; Lippmann, M.J.

1986-08-01T23:59:59.000Z

237

Understanding The Chena Hot Springs, Alaska, Geothermal System Using  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Understanding The Chena Hot Springs, Alaska, Geothermal System Using Temperature And Pressure Data From Exploration Boreholes Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Understanding The Chena Hot Springs, Alaska, Geothermal System Using Temperature And Pressure Data From Exploration Boreholes Details Activities (7) Areas (1) Regions (0) Abstract: Chena Hot Springs is a small, moderate temperature, deep circulating geothermal system, apparently typical of those associated to hot springs of interior Alaska. Multi-stage drilling was used in some

238

Conceptual design of a geothermal site development forecasting system  

DOE Green Energy (OSTI)

A site development forecasting system has been designed in response to the need to monitor and forecast the development of specific geothermal resource sites for electrical power generation and direct heat applications. The system is comprised of customized software, a site development status data base, and a set of complex geothermal project development schedules. The system would use site-specific development status information obtained from the Geothermal Progress Monitor and other data derived from economic and market penetration studies to produce reports on the rates of geothermal energy development, federal agency manpower requirements to ensure these developments, and capital expenditures and technical/laborer manpower required to achieve these developments.

Neham, E.A.; Entingh, D.J.

1980-03-01T23:59:59.000Z

239

Geochemistry Of The Lake City Geothermal System, California, Usa | Open  

Open Energy Info (EERE)

Geochemistry Of The Lake City Geothermal System, California, Usa Geochemistry Of The Lake City Geothermal System, California, Usa Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Paper: Geochemistry Of The Lake City Geothermal System, California, Usa Details Activities (2) Areas (1) Regions (0) Abstract: Lake City hot springs and geothermal wells chemically fall into a narrow compositional group. This indicates that, with the exception of a few hot springs, mixing with shallow cold ground waters does not have a significant influence on the chemistry of the hot springs. Narrow ranges in plots of F, B and Li versus Cl, and _D to _18O values indicate minimal mixing. Because of this, the compositions of the natural hot spring waters are fairly representative of the parent geothermal water. The average

240

Geophysical Characterization of a Geothermal System Neal Hot Springs,  

Open Energy Info (EERE)

Characterization of a Geothermal System Neal Hot Springs, Characterization of a Geothermal System Neal Hot Springs, Oregon, USA Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Geophysical Characterization of a Geothermal System Neal Hot Springs, Oregon, USA Abstract Neal Hot Springs is an active geothermal area that is also the proposed location of a binary power plant, which is being developed by US Geothermal Inc. To date, two production wells have been drilled and an injection well is in the process of being completed. The primary goal of this field camp was to provide a learning experience for students studying geophysics, but a secondary goal was to characterize the Neal Hot Springs area to provide valuable information on the flow of geothermal fluids through the subsurface. This characterization was completed using a variety of

Note: This page contains sample records for the topic "rock geothermal systems" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Geothermal Resource Analysis And Structure Of Basin And Range Systems,  

Open Energy Info (EERE)

Analysis And Structure Of Basin And Range Systems, Analysis And Structure Of Basin And Range Systems, Especially Dixie Valley Geothermal Field, Nevada Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report: Geothermal Resource Analysis And Structure Of Basin And Range Systems, Especially Dixie Valley Geothermal Field, Nevada Details Activities (12) Areas (5) Regions (0) Abstract: Publish new thermal and drill data from the Dizie Valley Geothermal Field that affect evaluation of Basin and Range Geothermal Resources in a very major and positive way. Completed new geophysical surveys of Dizie Valley including gravity and aeromagnetics and integrated the geophysical, seismic, geological and drilling data at Dizie Valley into local and regional geologic models. Developed natural state mass and energy

242

Geothermal energy control system and method  

DOE Patents (OSTI)

A geothermal energy transfer and utilization system makes use of thermal energy stored in hot solute-bearing well water to generate super-heated steam from an injected flow of clean water; the super-heated steam is then used for operating a turbine-driven pump at the well bottom for pumping the hot solute-bearing water at high pressure and in liquid state to the earth's surface, where it is used by transfer of its heat to a closed-loop boiler-turbine-alternator combination for the generation of electrical or other power. Residual concentrated solute-bearing water is pumped back into the earth. The clean cooled water is regenerated at the surface-located system and is returned to the deep well pumping system also for lubrication of a novel bearing arrangement supporting the turbine-driven pump system. The bearing system employs liquid lubricated thrust and radial bearings with all bearing surfaces bathed in clean water serving as a lubricant and maintained under pressure to prevent entry into the bearings of contaminated geothermal fluid, an auxiliary thrust ball bearing arrangement comes into operation when starting or stopping the pumping system.

Matthews, Hugh B. (Acton, MA)

1977-01-01T23:59:59.000Z

243

Power produced from hot dry rock geothermal resources: a case study for the Imperial Valley, California  

SciTech Connect

The case study described here concerns an HDR system which provides geothermal fluids for a hypothetical electric plant located in California's Imperial Valley. Primary concern is focused on the implications of differing drilling conditions, as reflected by costs, and differing risk environments for the potential commercialization of an HDR system. Drilling costs for best, medium and worst drilling conditions are taken from a recent study of drilling costs for HDR systems. Differing risk environments are presented by differing rate of return requirements on stocks and interest on bonds which the HDR system is assumed to pay; rate of return/interest combinations considered are 6%/3%, 9%/6%, 12%/9% and 15%/12%. The method used for analyzing the HDR system involves a two-stage process. In stage 1, the maximum amount that the electric plant can pay to an HDR system for geothermal fluids is calculated for alternative busbar prices of electricity received by the electric plant. In stage 2, costs for the HDR system are calculated under differing assumed risk environments and drilling conditions. These two sets of data may then be used to analyze the minimum busbar price of electricity - which defines a maximum fuel bill that could be paid to the HDR system by the electric plant - which could result in the HDR system's full recouperation of all production and drilling costs.

Cummings, R.G.; Morris, G.E.; Arundale, C.J.; Erickson, E.L.

1979-12-01T23:59:59.000Z

244

Numerical simulation to study the feasibility of using CO2 as a stimulation agent for enhanced geothermal systems  

E-Print Network (OSTI)

stimulation of an enhanced geothermal system using a high pHTwenty-Ninth Workshop on Geothermal Reservoir Engineering,Calcite dissolution in geothermal reservoirs using chelants,

Xu, T.

2010-01-01T23:59:59.000Z

245

Role of Fluid Pressure in the Production Behavior of Enhanced Geothermal Systems with CO2 as Working Fluid  

E-Print Network (OSTI)

and Clay Swelling in a Fractured Geothermal Reservoir,Transactions, Geothermal Resources Council, Vol. 28, pp.2004b. Pruess, K. Enhanced Geothermal Systems (EGS) Using CO

Pruess, Karsten

2008-01-01T23:59:59.000Z

246

Characteristics of Basin and Range Geothermal Systems with Fluid  

Open Energy Info (EERE)

Characteristics of Basin and Range Geothermal Systems with Fluid Characteristics of Basin and Range Geothermal Systems with Fluid Temperatures of 150°C to 200°C Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Paper: Characteristics of Basin and Range Geothermal Systems with Fluid Temperatures of 150°C to 200°C Abstract Six geothermal reservoirs with fluid temperatures over 200°C and ten geothermal systems with measured fluid temperatures of 150-200°C have been discovered in the northern Basin and Range Province of the USA. A comparison of these high and moderate temperature systems shows considerable overlap in geographical distribution, geology, and physical properties. Our ability to distinguish between moderate and high temperature systems using fluid chemistry has been limited by often

247

Geothermal system saving money at fire station | Department of Energy  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Geothermal system saving money at fire station Geothermal system saving money at fire station Geothermal system saving money at fire station April 9, 2010 - 3:45pm Addthis Joshua DeLung What will the project do? A geothermal heating and cooling system has enabled the substation to save taxpayers $15,000 annually when compared to a traditional system. The high temperature of the treatment building's water helps reduce the amount of energy needed to heat water in the substation. An environmentally friendly geothermal heating and cooling system in Pennsylvania will save taxpayers $15,000 a year as part of a new fire substation that will decrease emergency response times. The Alpha Fire Co. celebrated the opening of substation on the ground floor of the College Township municipal building earlier this year in State

248

Blind Geothermal System Exploration in Active Volcanic Environments;  

Open Energy Info (EERE)

System Exploration in Active Volcanic Environments; System Exploration in Active Volcanic Environments; Multi-phase Geophysical and Geochemical Surveys in Overt and Subtle Volcanic Systems, Hawaii and Maui Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Blind Geothermal System Exploration in Active Volcanic Environments; Multi-phase Geophysical and Geochemical Surveys in Overt and Subtle Volcanic Systems, Hawai'i and Maui Project Type / Topic 1 Recovery Act: Geothermal Technologies Program Project Type / Topic 2 Validation of Innovative Exploration Technologies Project Description The project will perform a suite of stepped geophysical and geochemical surveys and syntheses at both a known, active volcanic system at Puna, Hawai'i and a blind geothermal system in Maui, Hawai'i. Established geophysical and geochemical techniques for geothermal exploration including gravity, major cations/anions and gas analysis will be combined with atypical implementations of additional geophysics (aeromagnetics) and geochemistry (CO2 flux, 14C measurements, helium isotopes and imaging spectroscopy). Importantly, the combination of detailed CO2 flux, 14C measurements and helium isotopes will provide the ability to directly map geothermal fluid upflow as expressed at the surface. Advantageously, the similar though active volcanic and hydrothermal systems on the east flanks of Kilauea have historically been the subject of both proposed geophysical surveys and some geochemistry; the Puna Geothermal Field (Puna) (operated by Puna Geothermal Venture [PGV], an Ormat subsidiary) will be used as a standard by which to compare both geophysical and geochemical results.

249

Temperature histories in geothermal wells: survey of rock thermomechanical properties and drilling, production, and injection case studies  

DOE Green Energy (OSTI)

Thermal and mechanical properties for geothermal formations are tabulated for a range of temperatures and stress conditions. Data was obtained from the technical literature and direct contacts with industry. Thermal properties include heat capacity, conductivity, and diffusivity. Undisturbed geothermal profiles are also presented. Mechanical properties include Youngs modulus and Poisson ratio. GEOTEMP thermal simulations of drilling, production and injection are reported for two geothermal regions, the hot dry rock area near Los Alamos and the East Mesa field in the Imperial Valley. Actual drilling, production, and injection histories are simulated. Results are documented in the form of printed GEOTEMP output and plots of temperatures versus depth, radius, and time. Discussion and interpretation of the results are presented for drilling and well completion design to determine: wellbore temperatures during drilling as a function of depth; bit temperatures over the drilling history; cement temperatures from setting to the end of drilling; and casing and formation temperatures during drilling, production, and injection.

Goodman, M.A.

1981-07-01T23:59:59.000Z

250

Economics of a conceptual 75 MW Hot Dry Rock geothermal electric power station  

DOE Green Energy (OSTI)

Man-made, Hot Dry Rock (HDR) geothermal energy reservoirs have been investigated for over ten years. As early as 1977 a research-sized reservoir was created at a depth of 2.9 km near the Valles Caldera, a dormant volcanic complex in New Mexico, by connecting two wells with hydraulic fractures. Thermal power was generated at rates of up to 5 MW(t) and the reservoir was operated for nearly a year with a thermal drawdown less than 10/sup 0/C. A small 60kW(e) electrical generation unit using a binary cycle (hot geothermal water and a low boiling point organic fluid, R-114) was operated. Interest is now worldwide with field research being conducted at sites near Le Mayet de Montagne, France; Falkenberg and Urach, Federal Republic of Germany; Yakedake, Japan; and Rosemanowes quarry in Cornwall, United Kingdom. To assess the commercial viability of future HDR electrical generating stations, an economic modeling study was conducted for a conceptual 75 MW(e) generating station operating at conditions similar to those prevailing at the New Mexico HDR site. The reservoir required for 75 MW(e), equivalent to 550 MW of thermal energy, uses at least 9 wells drilled to 4.3 km and the temperature of the water produced should average 230/sup 0/C. Thermodynamic considerations indicate that a binary cycle should result in optimum electricity generation and the best organic fluids are refrigerants R-22, R-32, R-115 or R-600a (Isobutane). The break-even bus bar cost of HDR electricity was computed by the levelized life-cycle method, and found to be competitive with most alternative electric power stations in the US.

Murphy, H.D.; Drake, R.H.; Tester, J.W.; Zyvoloski, G.A.

1984-01-01T23:59:59.000Z

251

Seismological investigation of crack formation in hydraulic rock fracturing experiments and in natural geothermal environments. Progress report, September 1, 1979-August 31, 1980  

DOE Green Energy (OSTI)

Progress is reported in the following research areas: a synthesis of seismic experiments at the Fenton Hill Hot-Dry-Rock System; attenuation of high-frequency shear waves in the lithosphere; a new kinematic source model for deep volcanic tremors; ground motion in the near-field of a fluid-driven crack and its interpretation in the study of shallow volcanic tremor; low-velocity bodies under geothermal areas; and operation of event recorders in Mt. St. Helens and Newberry Peak with preliminary results from them. (MHR)

Aki, K.

1980-09-01T23:59:59.000Z

252

Preliminary measurements of the thermal conductivity of rocks from LASL geothermal test holes GT-1 and GT-2  

DOE Green Energy (OSTI)

The conductivities on a number of dry rocks have been measured in an air environment. These experimental values are probably about 10 percent lower than the in situ values. Initial attempts to prepare ''wet'' rock samples (rocks saturated with water) have so far resulted in only ''damp'' rocks. Considerable effort will be required to characterize the crack system in ''solid'' rocks and to predict the probable conductivity values for in situ conditions.

Sibbitt, W.L.

1975-12-01T23:59:59.000Z

253

Strategies To Detect Hidden Geothermal Systems Based On Monitoring and  

Open Energy Info (EERE)

To Detect Hidden Geothermal Systems Based On Monitoring and To Detect Hidden Geothermal Systems Based On Monitoring and Analysis Of CO2 In The Near-Surface Environment Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Strategies To Detect Hidden Geothermal Systems Based On Monitoring and Analysis Of CO2 In The Near-Surface Environment Details Activities (5) Areas (1) Regions (0) Abstract: We investigate the potential for CO2 monitoring in thenear-surface environment as an approach to exploration for hiddengeothermal systems. Numerical simulations of CO2 migration from a modelhidden geothermal system show that CO2 concentrations can reach highlevels in the shallow subsurface even for relatively low CO2 fluxes.Therefore, subsurface measurements offer an advantage over above-groundmeasurements which are affected by winds that rapidly disperse

254

Behavior of Rare Earth Elements in Geothermal Systems- A New  

Open Energy Info (EERE)

Behavior of Rare Earth Elements in Geothermal Systems- A New Behavior of Rare Earth Elements in Geothermal Systems- A New Exploration/Exploitation Tool? Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Behavior of Rare Earth Elements in Geothermal Systems- A New Exploration/Exploitation Tool? Abstract N/A Author Department of Geology and Geological Engineering niversity of Idaho Published Publisher Not Provided, 2001 DOI Not Provided Check for DOI availability: http://crossref.org Online Internet link for Behavior of Rare Earth Elements in Geothermal Systems- A New Exploration/Exploitation Tool? Citation Department of Geology and Geological Engineering niversity of Idaho. 2001. Behavior of Rare Earth Elements in Geothermal Systems- A New Exploration/Exploitation Tool?. (!) : (!) . Retrieved from

255

Development of Exploration Methods for Engineered Geothermal Systems  

Open Energy Info (EERE)

Development of Exploration Methods for Engineered Geothermal Systems Development of Exploration Methods for Engineered Geothermal Systems through Integrated Geophysical, Geologic and Geochemical Interpretation Jump to: navigation, search OpenEI Reference LibraryAdd to library Web Site: Development of Exploration Methods for Engineered Geothermal Systems through Integrated Geophysical, Geologic and Geochemical Interpretation Abstract N/A Author U.S. Department of Energy Published Publisher Not Provided, Date Not Provided DOI Not Provided Check for DOI availability: http://crossref.org Online Internet link for Development of Exploration Methods for Engineered Geothermal Systems through Integrated Geophysical, Geologic and Geochemical Interpretation Citation U.S. Department of Energy. Development of Exploration Methods for Engineered Geothermal Systems through Integrated Geophysical, Geologic and

256

Assessment of Favorable Structural Settings of Geothermal Systems in the  

Open Energy Info (EERE)

Assessment of Favorable Structural Settings of Geothermal Systems in the Assessment of Favorable Structural Settings of Geothermal Systems in the Great Basin, Western USA Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Paper: Assessment of Favorable Structural Settings of Geothermal Systems in the Great Basin, Western USA Abstract We have undertaken a thorough inventory of the structural settings of known geothermal systems (>400 total) in the extensional to transtensional terrane of the Great Basin in the western USA. Of the more than 200 geothermal fields catalogued to date, we found that step-overs or relay ramps in normal fault zones served as the most favorable structural setting, hosting ~32% of the systems. Such areas are characterized by multiple, commonly overlapping fault strands, increased fracture density,

257

Geothermal energy control system and method  

DOE Patents (OSTI)

A geothermal energy transfer and utilization system makes use of thermal energy stored in hot solute-bearing well water to generate super-heated steam from an injected flow of clean water; the super-heated steam is then used for operating a turbine-driven pump at the well bottom for pumping the hot solute-bearing water at high pressure and in liquid state to the earth's surface, where it is used by transfer of its heat to a closed-loop boiler-turbine-alternator combination for the generation of electrical or other power. Residual concentrated solute-bearing water is pumped back into the earth. The clean cooled water is regenerated at the surface-located system and is returned to the deep well pumping system also for lubrication of a novel bearing arrangement supporting the turbine-driven pump system.

Matthews, Hugh B. (Acton, MA)

1976-01-01T23:59:59.000Z

258

The Krafla Geothermal System. A Review of Geothermal Research and Revision  

Open Energy Info (EERE)

form form View source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit with form History Facebook icon Twitter icon » The Krafla Geothermal System. A Review of Geothermal Research and Revision of the Conceptual Model Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: The Krafla Geothermal System. A Review of Geothermal Research and Revision of the Conceptual Model Authors Mortensen A.K., Gudmundsson Á., Steingrímsson B., Sigmundsson F., Axelsson G., Ármannsson H., Björnsson H., Ágústsson K., Saemundsson K., Ólafsson M., Karlsdóttir R., Halldórsdóttir S. and Hauksson T. Organization Iceland GeoSurvey Published Iceland GeoSurvey, 2009

259

Overview Of The Lake City, California Geothermal System | Open Energy  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Overview Of The Lake City, California Geothermal System Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Paper: Overview Of The Lake City, California Geothermal System Details Activities (1) Areas (1) Regions (0) Abstract: Following a spectacular mud volcano eruption in 1951, the Lake City geothermal system has been intermittently explored for 44 years. A discovery well was drilled 30 years ago. The geothermal system is associated with a two mile-long, north-south trending, abnormally complex section of the active Surprise Valley fault zone that has uplifted the

260

Geothermal Progress Monitor: system status and operational experience  

SciTech Connect

The Geothermal Progress Monitor (GPM) is an information system designed and implemented by the MITRE Corporation on behalf of the Division of Geothermal and Hydropower Technology (DGHT, formerly Division of Geothermal Energy) of the US Department of Energy (DOE). Its purpose is to keep track of and to report significant events and trends in the US geothermal industry and the federal geothermal program. The information sources of the GPM system are paper and computerized files maintained by a number of organizations throughout the United States. Trade and technical publications are also used to supplement the information-gathering network. Periodic reports from the GPM system consist mainly of manual and computerized analyses of the collected data. In addition, significant events and activities are usually highlighted. The GPM serves a dual function for DGHT and other members of the Interagency Geothermal Coordinating Council (IGCC). It supports effective management of the federal geothermal program and it provides information for executive, legislative, statutory, and public needs. This paper is a report on the current status of the GPM system and a summary of MITRE's operational experience during calendar year 1981 and the first quarter of 1982. It includes a description of the required output and the mechanism by which the information is gathered, integrated, and published as a Geothermal Progress Monitor Report.

Gerstein, R.E.; Kenkeremath, L.D.; Murphy, M.B.; Entingh, D.J.

1982-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "rock geothermal systems" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Geothermal Progress Monitor: system status and operational experience  

DOE Green Energy (OSTI)

The Geothermal Progress Monitor (GPM) is an information system designed and implemented by the MITRE Corporation on behalf of the Division of Geothermal and Hydropower Technology (DGHT, formerly Division of Geothermal Energy) of the US Department of Energy (DOE). Its purpose is to keep track of and to report significant events and trends in the US geothermal industry and the federal geothermal program. The information sources of the GPM system are paper and computerized files maintained by a number of organizations throughout the United States. Trade and technical publications are also used to supplement the information-gathering network. Periodic reports from the GPM system consist mainly of manual and computerized analyses of the collected data. In addition, significant events and activities are usually highlighted. The GPM serves a dual function for DGHT and other members of the Interagency Geothermal Coordinating Council (IGCC). It supports effective management of the federal geothermal program and it provides information for executive, legislative, statutory, and public needs. This paper is a report on the current status of the GPM system and a summary of MITRE's operational experience during calendar year 1981 and the first quarter of 1982. It includes a description of the required output and the mechanism by which the information is gathered, integrated, and published as a Geothermal Progress Monitor Report.

Gerstein, R.E.; Kenkeremath, L.D.; Murphy, M.B.; Entingh, D.J.

1982-03-01T23:59:59.000Z

262

Chemical Geothermometers And Mixing Models For Geothermal Systems | Open  

Open Energy Info (EERE)

Geothermometers And Mixing Models For Geothermal Systems Geothermometers And Mixing Models For Geothermal Systems Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Chemical Geothermometers And Mixing Models For Geothermal Systems Details Activities (1) Areas (1) Regions (0) Abstract: Qualitative chemical geothermometers utilize anomalous concentrations of various "indicator" elements in groundwaters, streams, soils, and soil gases to outline favorable places to explore for geothermal energy. Some of the qualitative methods, such as the delineation of mercury and helium anomalies in soil gases, do not require the presence of hot springs or fumaroles. However, these techniques may also outline fossil thermal areas that are now cold. Quantitative chemical geothermometers and mixing models can provide information about present probable minimum

263

Large Scale Geothermal Exchange System for Residential, Office and Retail  

Open Energy Info (EERE)

Geothermal Exchange System for Residential, Office and Retail Geothermal Exchange System for Residential, Office and Retail Development Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Large Scale Geothermal Exchange System for Residential, Office and Retail Development Project Type / Topic 1 Recovery Act - Geothermal Technologies Program: Ground Source Heat Pumps Project Type / Topic 2 Topic Area 1: Technology Demonstration Projects Project Description RiverHeath will be a new neighborhood, with residences, shops, restaurants, and offices. The design incorporates walking trails, community gardens, green roofs, and innovative stormwater controls. A major component of the project is our reliance on renewable energy. One legacy of the land's industrial past is an onsite hydro-electric facility which formerly powered the paper factories. The onsite hydro is being refurbished and will furnish 100% of the project's electricity demand.

264

Regional Systems Development for Geothermal Energy Resources Pacific Region  

Open Energy Info (EERE)

Systems Development for Geothermal Energy Resources Pacific Region Systems Development for Geothermal Energy Resources Pacific Region (California and Hawaii). Task 3: water resources evaluation. Topical report Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report: Regional Systems Development for Geothermal Energy Resources Pacific Region (California and Hawaii). Task 3: water resources evaluation. Topical report Details Activities (1) Areas (1) Regions (0) Abstract: The fundamental objective of the water resources analysis was to assess the availability of surface and ground water for potential use as power plant make-up water in the major geothermal areas of California. The analysis was concentrated on identifying the major sources of surface and ground water, potential limitations on the usage of this water, and the

265

Geothermal energy  

SciTech Connect

Dry hot rock in the Earth's crust represents the largest and most broadly distributed reservoir of usable energy accessible to man. The engineering equipment and methods required to extract and use this energy appear to exist and are now being investigated actively at LASL. At least for deep systems in relatively impermeable rock, not close to active faults, the extraction of energy frtom dry geothermal resertvoirs should involve no significant environmental hazards. The principal environmental effects of such energy systems will be those associated with the surface facilities that use the geothermal heat; these will be visual, in land use, and in the thermal-pollution potential of low-temperature power plants. The energy extraction system itself should be clean; safe, unobtrusive, and economical. (auth)

Smith, M.C.

1973-01-01T23:59:59.000Z

266

Summary of hot dry rock geothermal reservoir testing 1978 to 1980  

DOE Green Energy (OSTI)

Experimental results and re-evaluation of the Phase I Hot Dry Rock Geothermal Energy reservoirs at the Fenton Hill field site are summarized. Reservoir growth is traced. Reservoir growth was caused not only by pressurization and hydraulic fracturing, but also by heat extraction and thermal contraction effects. Reservoir heat-transfer area grew from 8000 to 50,000 m/sup 2/ and reservoir fracture volume grew from 11 to 266/sup 3/m. Despite this reservoir growth, the water loss rate increased only 30%, under similar pressure environments. For comparable temperature and pressure conditions, the flow impedance (a measure of the resistance to circulation of water through the reservoir) remained essentially unchanged, and if reproduced in the Phase II reservoir under development, could result in self pumping. Geochemical and seismic hazards have been nonexistent in the Phase I reservoirs. The produced water is relatively low in total dissolved solids and shows little tendency for corrosion or scaling. The largest microearthquake associated with heat extraction measures less than -1 on the extrapolated Richter scale.

Dash, Z.V.; Murphy, H.D. (eds.)

1981-01-01T23:59:59.000Z

267

Environmental studies conducted at the Fenton Hill Hot Dry Rock geothermal development site  

DOE Green Energy (OSTI)

An environmental investigation of Hot Dry Rock (HDR) geothermal development was conducted at Fenton Hill, New Mexico, during 1976-1979. Activities at the Fenton Hill Site included an evaluation of baseline data for biotic and abiotic ecosystem components. Identification of contaminants produced by HDR processes that had the potential for reaching the surrounding environment is also discussed. Three dominant vegetative communities were identified in the vicinity of the site. These included grass-forb, aspen, and mixed conifer communities. The grass-forb area was identified as having the highest number of species encountered, with Phleum pratense and Dactylis glomerata being the dominant grass species. Frequency of occurrence and mean coverage values are also given for other species in the three main vegetative complexes. Live trapping of small mammals was conducted to determine species composition, densities, population, and diversity estimates for this component of the ecosystem. The data indicate that Peromyscus maniculatus was the dominant species across all trapping sites during the study. Comparisons of relative density of small mammals among the various trapping sites show the grass-forb vegetative community to have had the highest overall density. Comparisons of small mammal diversity for the three main vegetative complexes indicate that the aspen habitat had the highest diversity and the grass-forb habitat had the lowest. Analyses of waste waters from the closed circulation loop indicate that several trace contaminants (e.g., arsenic, cadmium, fluoride, boron, and lithium) were present at concentrations greater than those reported for surface waters of the region.

Miera, F.R. Jr.; Langhorst, G.; McEllin, S.; Montoya, C.

1984-05-01T23:59:59.000Z

268

Surface water supply for the Clearlake, California Hot Dry Rock Geothermal Project  

DOE Green Energy (OSTI)

It is proposed to construct a demonstration Hot Dry Rock (HDR) geothermal plant in the vicinity of the City of Clearlake. An interim evaluation has been made of the availability of surface water to supply the plant. The evaluation has required consideration of the likely water consumption of such a plant. It has also required consideration of population, land, and water uses in the drainage basins adjacent to Clear Lake, where the HDR demonstration project is likely to be located. Five sources were identified that appear to be able to supply water of suitable quality in adequate quantity for initial filling of the reservoir, and on a continuing basis, as makeup for water losses during operation. Those sources are California Cities Water Company, a municipal supplier to the City of Clearlake; Clear Lake, controlled by Yolo County Flood Control and Water Conservation District; Borax Lake, controlled by a local developer; Southeast Regional Wastewater Treatment Plant, controlled by Lake County; and wells, ponds, and streams on private land. The evaluation involved the water uses, water rights, stream flows, precipitation, evaporation, a water balance, and water quality. In spite of California`s prolonged drought, the interim conclusion is that adequate water is available at a reasonable cost to supply the proposed HDR demonstration project.

Jager, A.R.

1996-03-01T23:59:59.000Z

269

Planning and drilling geothermal energy extraction hole EE-2: a precisely oriented and deviated hole in hot granitic rock  

DOE Green Energy (OSTI)

During the preceding work (Phase I) of the Hot Dry Rock (HDR) Geothermal Energy Project at Fenton Hill, two holes were drilled to a depth of nearly 3048 m (10,000 ft) and connected by a vertical hydraulic fracture. In this phase, water was pumped through the underground reservoir for approximately 417 days, producing an energy equivalent of 3 to 5 MW(t). Energy Extraction Hole No. 2 (EE-2) is the first of two deep holes that will be used in the Engineering-Resource Development System (Phase II) of the ongoing HDR Project of the Los Alamos National Laboratory. This phase of the work consists of drilling two parallel boreholes, inclined in their lower, open-hole sections at 35/sup 0/ to the vertical and separated by a vertical distance of 366 m (1200 ft) between the inclined parts of the drill holes. The holes will be connected by a series of vertical, hydraulically produced fractures in the Precambrian granitic rock complex. EE-2 was drilled to a depth of 4660 m (15,289 ft), where the bottom-hole temperature is approximately 320/sup 0/C (608/sup 0/F). Directional drilling techniques were used to control the azimuth and deviation of the hole. Upgrading of the temperature capability of existing hardware, and development of new equipment was necessary to complete the drilling of the hole in the extremely hot, hard, and abrasive granitic formation. The drilling history and the problems with bits, directional tools, tubular goods, cementing, and logging are described. A discussion of the problems and recommendations for overcoming them are also presented.

Helmick, C.; Koczan, S.; Pettitt, R.

1982-04-01T23:59:59.000Z

270

GRC Workshop: The Power of the National Geothermal Data System | Department  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

GRC Workshop: The Power of the National Geothermal Data System GRC Workshop: The Power of the National Geothermal Data System GRC Workshop: The Power of the National Geothermal Data System October 2, 2013 (All day) Flyer for the National Geothermal Data System workshop at the Geothermal Resources Council Annual Meeting on October 2, 2013 in Las Vegas. Drilling Down: How Legacy and New Research Data Can Advance Geothermal Development-The Power of the National Geothermal Data System (NGDS) A workshop at the Geothermal Resources Council Annual Meeting in Las Vegas, Nevada Abstract: The National Geothermal Data System's (NGDS) launch in 2014 will provide open access to millions of datasets, sharing technical geothermal-relevant data across the geosciences to propel geothermal development and production forward. By aggregating findings from the Energy Department's RD&D projects

271

Conceptual Models of Geothermal Systems - Introduction | Open Energy  

Open Energy Info (EERE)

Conceptual Models of Geothermal Systems - Introduction Conceptual Models of Geothermal Systems - Introduction Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Paper: Conceptual Models of Geothermal Systems - Introduction Abstract The key to the successful exploration, development (incl. drilling) and utilization of any type of geothermal system is a clear definition and understanding of the nature and characteristics of the system in question. This is best achieved through the development of a conceptual model of the system, which is a descriptive or qualitative model incorporating, and unifying, the essential physical features of the system. Conceptual models are mainly based on analysis of geological and geophysical information, temperature and pressure data, information on reservoir properties as well

272

Design, construction and evaluation of a simulated geothermal flow system  

Science Conference Proceedings (OSTI)

A system was designed and built to simulate the flow from a geothermal well. The simulated flow will be used to power a Lysholm engine, the performance of which will then be evaluated for different simulated geothermal flows. Two main subjects are covered: 1) the design, construction and evaluation of the behavior of the system that simulates the geothermal flow; included in that topic is a discussion of the probable behavior of the Lysholm engine when it is put into operation, and 2) the investigation of the use of dynamic modeling techniques to determine whether they can provide a suitable means for predicting the behavior of the system.

Mackanic, J.C.

1980-07-28T23:59:59.000Z

273

Results of fluid-circulation experiments: LASL hot dry rock geothermal project  

DOE Green Energy (OSTI)

The first large-scale field experiment to investigate the extraction of heat from hot dry rock is now in progress on the Jemez Plateau in northern New Mexico. The experimental system consists of two holes about 3 km deep, from each of which hydraulic fractures have been made. The two major fractures appear to be approximately vertical and parallel, and separated by about 9 m of granodiorite through which fluid is transmitted probably along a distributed set of secondary fractures. Experiments to this point have demonstrated that the surface area of each hydraulic fracture is sufficient to accomplish effective heat transfer from the rock, at about 200/sup 0/C, to water circulated through the system; that there is no significant short-circuiting of the water within the fractures; but that the impedance to fluid flow through the rock between the fractures is too high to permit the rate of heat extraction (initially about 10 MWt) desired of the experimental system. An attempt to reduce impedance by leaching with dilute sodium carbonate solution was unsuccessful. Therefore an attempt is now being made to reduce it by re-drilling from near the bottom of one hole in order to produce a simple system geometry in which the two holes are connected directly through a single hydraulic fracture.

Smith, M.C.

1977-01-01T23:59:59.000Z

274

Hybrid Cooling Systems for Low-Temperature Geothermal Power Production  

NLE Websites -- All DOE Office Websites (Extended Search)

LLC. Contract No. DE-AC36-08GO28308 Hybrid Cooling Systems for Low-Temperature Geothermal Power Production Andrea Ashwood and Desikan Bharathan Technical Report NREL...

275

NUMERICAL SIMULATION OF RESERVOIR COMPACTION IN LIQUID DOMINATED GEOTHERMAL SYSTEMS  

E-Print Network (OSTI)

4 x 104 kg/day of water were produced and 3.2 x 104 kg/dayand water through a porous geothermal system, including the vertical deformations produced

Lippmann, M.J.

2010-01-01T23:59:59.000Z

276

Fluid Imaging of Enhanced Geothermal Systems through Joint 3D Geophysical  

Open Energy Info (EERE)

Imaging of Enhanced Geothermal Systems through Joint 3D Geophysical Imaging of Enhanced Geothermal Systems through Joint 3D Geophysical Inverse Modeling Geothermal Lab Call Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Fluid Imaging of Enhanced Geothermal Systems through Joint 3D Geophysical Inverse Modeling Project Type / Topic 1 Laboratory Call for Submission of Applications for Research, Development and Analysis of Geothermal Technologies Project Type / Topic 2 Fluid Imaging Project Description EGS has been defined as enhanced reservoirs that have been created to extract economical amounts of heat from low permeability and/or porosity geothermal resources. Critical to the success of EGS is the successful manipulation of fluids in the subsurface to enhance permeability. Knowledge in the change in volume and location of fluids in the rocks and fractures (both natural and induced) will be needed to manage injection strategies such as the number and location of step out wells, in-fill wells and the ratio of injection to production wells. The key difficulty in manipulating fluids has been our inability to reliably predict their locations, movements and concentrations. We believe combining data from MEQ and electrical surveys has the potential to overcome these problems and can meet many of the above needs, economically. Induced seismicity is currently viewed as one of the essential methods for inferring the success of creating fracture permeability and fluid paths during large scale EGS injections. Fluids are obviously playing a critical role in inducing the seismicity, however, other effects such as thermal, geochemical and stress redistribution, etc. may also play a role.

277

Economic Predictions for Heat Mining: A Review and Analysis of Hot Dry Rock (HDR) Geothermal Energy Technology  

DOE Green Energy (OSTI)

The main objectives of this study were first, to review and analyze several economic assessments of Hot Dry Rock (HDR) geothermal energy systems, and second, to reformulate an economic model for HDR with revised cost components. The economic models reviewed include the following studies sponsored by Electric Power Research Institute (EPRI)-Cummings and Morris (1979), Los Alamos National Laboratory (LANL)-Murphy, et al. (1982), United Kingdom (UK)-Shock (1986), Japan-Hori, et al. (1986), Meridian-Entingh (1987) and Bechtel (1988). A general evaluation of the technical feasibility of HDR technology components was also conducted in view of their importance in establishing drilling and reservoir performance parameters required for any economic assessment. In this review, only economic projections for base load electricity produced from HDR systems were considered. Bases of 1989 collars ($) were selected to normalize costs. Following the evaluation of drilling and reservoir performance, power plant choices and cost estimates are discussed in section 6 of the report. In Section 7, the six economics studies cited above are reviewed and compared in terms of their key resource, reservoir and plant performance, and cost assumptions. Based on these comparisons, the report estimates parameters for three composite cases. Important parameters include: (1) resource quality-average geothermal gradient (C/km) and well depth, (2) reservoir performance-effective productivity, flow impedance, and lifetime (thermal drawdown rate), (3) cost components-drilling, reservoir formation, and power plant costs and (4) economic factors-discount and interest rates, taxes, etc. In Section 8, composite case conditions were used to reassess economic projections for HDR-produced electricity. In Section 9, a generalized economic model for HDR-produced electricity is presented to show the effects of resource grade, reservoir performance parameters, and other important factors on projected costs. A sensitivity and uncertainty analysis using this model is given in Section 10. Section 11 treats a modification of the economic model for predicting costs for direct, non-electric applications. HDR economic projections for the U.S. are broken down by region in Section 12. In Section 13, the report provides recommendations for continued research and development to reduce technical and economic uncertainties relevant to the commercialization of HDR. [DJE-2005

Tester, Jefferson W.; Herzog, Howard J.

1990-07-01T23:59:59.000Z

278

Further Developments on the Geothermal System Scoping Model: Preprint  

Science Conference Proceedings (OSTI)

This paper discusses further developments and refinements for the uses of the Geothermal System Scoping Model in an effort to provide a means for performing a variety of trade-off analyses of surface and subsurface parameters, sensitivity analyses, and other systems engineering studies in order to better inform R&D direction and investment for the development of geothermal power into a major contributor to the U.S. energy supply.

Antkowiak, M.; Sargent, R.; Geiger, J. W.

2010-07-01T23:59:59.000Z

279

Heat pump assisted geothermal heating system for Felix Spa, Romania  

Science Conference Proceedings (OSTI)

The paper presents a pre-feasibility type study of a proposed heat pump assisted geothermal heating system for an average hotel in Felix Spa, Romania. After a brief presentation of the geothermal reservoir, the paper gives the methodology and the results of the technical and economical calculations. The technical and economical viability of the proposed system is discussed in detail in the final part of the paper.

Rosca, Marcel; Maghiar, Teodor

1996-01-24T23:59:59.000Z

280

Engineered Geothermal Systems Energy Return On Energy Investment  

NLE Websites -- All DOE Office Websites (Extended Search)

EGS EROI - 1 EGS EROI - 1 Engineered Geothermal Systems Energy Return On Energy Investment A.J. Mansure, Geothermal Consultant, ajm@q.com Albuquerque, NM 12/10/2012 Key Words: energy, EROI, EGS, efficiency, energy investment, energy return, input energy, energy payback, and net energy. Abstract Energy Return On Investment (EROI) is an important figure of merit for assessing the viability of energy alternatives. Too often comparisons of energy systems use "efficiency" when EROI would be more appropriate. For geothermal electric power generation, EROI is determined by the electricity delivered to the consumer compared to the energy consumed to construct, operate, and decommission the facility. Critical factors in determining the EROI of Engineered Geothermal Systems (EGS

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281

Identification of a New Blind Geothermal System with Hyperspectral Remote  

Open Energy Info (EERE)

Identification of a New Blind Geothermal System with Hyperspectral Remote Identification of a New Blind Geothermal System with Hyperspectral Remote Sensing and Shallow Temperature Measurements at Columbus Salt Marsh, Esmeralda County, Nevada Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Paper: Identification of a New Blind Geothermal System with Hyperspectral Remote Sensing and Shallow Temperature Measurements at Columbus Salt Marsh, Esmeralda County, Nevada Abstract Hyperspectral remote sensing-derived mineral maps and follow-up shallow temperature measurements were used to identify a new blind geothermal target in the Columbus Salt Marsh playa, Esmeralda County, Nevada. The hyperspectral survey was conducted with the ProSpecTIR VS2 instrument and consists of 380 km2 of 4-meter spatial resolution data acquired on October

282

A Geochemical Model Of The Platanares Geothermal System, Honduras | Open  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » A Geochemical Model Of The Platanares Geothermal System, Honduras Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: A Geochemical Model Of The Platanares Geothermal System, Honduras Details Activities (0) Areas (0) Regions (0) Abstract: Results of exploration drilling combined with results of geologic, geophysical, and hydrogeochemical investigations have been used to construct a geochemical model of the Platanares geothermal system, Honduras. Three coreholes were drilled, two of which produced fluids from fractured Miocene andesite and altered Cretaceous to Eocene conglomerate at

283

Fracture Propagation and Permeability Change under Poro-thermoelastic Loads & Silica Reactivity in Enhanced Geothermal Systems  

SciTech Connect

Geothermal energy is recovered by circulating water through heat exchange areas within a hot rock mass. Geothermal reservoir rock masses generally consist of igneous and metamorphic rocks that have low matrix permeability. Therefore, cracks and fractures play a significant role in extraction of geothermal energy by providing the major pathways for fluid flow and heat exchange. Therefore, knowledge of the conditions leading to formation of fractures and fracture networks is of paramount importance. Furthermore, in the absence of natural fractures or adequate connectivity, artificial fractures are created in the reservoir using hydraulic fracturing. Multiple fractures are preferred because of the large size necessary when using only a single fracture. Although the basic idea is rather simple, hydraulic fracturing is a complex process involving interactions of high pressure fluid injections with a stressed hot rock mass, mechanical interaction of induced fractures with existing natural fractures, and the spatial and temporal variations of in-situ stress. As a result, it is necessary to develop tools that can be used to study these interactions as an integral part of a comprehensive approach to geothermal reservoir development, particularly enhanced geothermal systems. In response to this need we have developed advanced poro-thermo-chemo-mechanical fracture models for rock fracture research in support of EGS design. The fracture propagation models are based on a regular displacement discontinuity formulation. The fracture propagation studies include modeling interaction of induced fractures. In addition to the fracture propagation studies, two-dimensional solution algorithms have been developed and used to estimate the impact of pro-thermo-chemical processes on fracture permeability and reservoir pressure. Fracture permeability variation is studied using a coupled thermo-chemical model with quartz reaction kinetics. The model is applied to study quartz precipitation/dissolution, as well as the variation in fracture aperture and pressure. Also, a three-dimensional model of injection/extraction has been developed to consider the impact poro- and thermoelastic stresses on fracture slip and injection pressure. These investigations shed light on the processes involved in the observed phenomenon of injection pressure variation (e.g., in Coso), and allow the assessment of the potential of thermal and chemical stimulation strategies.

Ahmad Ghassemi

2009-10-01T23:59:59.000Z

284

Monitoring well systems in geothermal areas  

DOE Green Energy (OSTI)

The ability to monitor the injection of spent geothermal fluids at reasonable cost might be greatly improved by use of multiple-completion techniques. Several such techniques, identified through contact with a broad range of experts from the groundwater and petroleum industries, are evaluated relative to application in the typical geologic and hydrologic conditions of the Basin and Range Province of the Western United States. Three basic monitor well designs are suggested for collection of pressure and temperature data: Single standpipe, multiple standpipe, and closed-system piezometers. A fourth design, monitor well/injection well dual completions, is determined to be inadvisable. Also, while it is recognized that water quality data is equally important, designs to allow water sampling greatly increase costs of construction, and so such designs are not included in this review. The single standpipe piezometer is recommended for use at depths less than 152 m (500 ft); several can be clustered in one area to provide information on vertical flow conditions. At depths greater than 152 m (500 ft), the multiple-completion standpipe and closed-system piezometers are likely to be more cost effective. Unique conditions at each monitor well site may necessitate consideration of the single standpipe piezometer even for deeper completions.

Lofgren, B.E.; O'Rourke, J.; Sterrett, R.; Thackston, J.; Fain, D.

1982-03-01T23:59:59.000Z

285

Hydrogeochemical evaluation of conventional and hot dry rock geothermal resource potential in the Clear Lake region, California  

DOE Green Energy (OSTI)

Chemistry, stable isotope, and tritium contents of thermal/mineral waters in the Clear Lake region were used to evaluate conventional and hot dry rock (HDR) geothermal potential for electrical generation. Thermal/mineral waters of the Clear Lake region are broadly classified as thermal meteoric and connate types based on chemical and isotopic criteria. Ratios of conservative components such as B/Cl are extremely different among all thermal/mineral waters of the Clear Lake region except for clusters of waters emerging from specific areas such as the Wilbur Springs district and the Agricultural Park area south of Mt. Konocti. In contrast ratios of conservative components in large, homogeneous geothermal reservoirs are constant. Stable isotope values of Clear Lake region waters show a mixing trend between thermal meteoric and connate (generic) end-members. The latter end-member has enriched {delta}D as well as enriched {delta}{sup 18}O, from typical high-temperature geothermal reservoir waters. Tritium data indicate most Clear Lake region waters are mixtures of old and young fluid components. Subsurface equilibration temperature of most thermal/mineral waters of the Clear Lake region is {le}150{degree}C based on chemical geothermometers but it is recognized that Clear Lake region waters are not typical geothermal fluids and that they violate rules of application of many geothermometers. The combined data indicate that no large geothermal reservoir underlies the Clear Lake region and that small localized reservoirs have equilibration temperatures {le}150{degree}C (except for Sulphur Bank mine). HDR technologies are probably the best way to commercially exploit the known high-temperatures existing beneath the Clear Lake region particularly within and near the main Clear Lake volcanic field.

Goff, F.; Adams, A.I.; Trujillo, P.E.; Counce, D.

1993-05-01T23:59:59.000Z

286

Geothermal heating system and method of installing the same  

SciTech Connect

A geothermal system and method of installing the same comprises the steps successively driving a drive pipe structure vertically into the ground at a plurality of locations so that a major portion of the length of the drive pipe structure is located below the frost line. An elongate geothermal pipe having closed ends is inserted into the drive pipe structure and its lower end is interlocked with a drive point device located at the lower end of the drive pipe structure. Thereafter, when the drive pipe is removed, the geothermal pipe remains anchored to the drive point. The geothermal pipes are connected together by conduits and connected to a heat pump so that a heat exchange liquid will be circulated through the system.

Kees, E.J.; Steiger, D.W.

1981-09-01T23:59:59.000Z

287

Geothermal well log interpretation midterm report  

DOE Green Energy (OSTI)

Reservoir types are defined according to fluid phase and temperature, lithology, geologic province, pore geometry, and salinity and fluid chemistry. Improvements are needed in lithology and porosity definition, fracture detection, and thermal evaluation for more accurate interpretation. Further efforts are directed toward improving diagnostic techniques for relating rock characteristics and log response, developing petrophysical models for geothermal systems, and developing thermal evaluation techniques. The Geothermal Well Log Interpretation study and report has concentrated only on hydrothermal geothermal reservoirs. Other geothermal reservoirs (hot dry rock, geopressured, etc.) are not considered.

Sanyal, S.K.; Wells, L.E.; Bickham, R.E.

1979-02-01T23:59:59.000Z

288

Environmental Development Plan (EDP). Geothermal energy systems, 1977  

DOE Green Energy (OSTI)

The Geothermal Energy Systems Environmental Development Plan (EDP) identifies the environmental, health, safety, social, and economic issues which are associated with the development, demonstration, and commercialization of geothermal resources and conversion technology. The EDP also describes the actions and implementation strategy required to resolve the issues identified. These actions may include the initiation of R and D activities, operations monitoring, baseline characterization studies, or activities leading to the development of standards and criteria in concert with other responsible agencies.

Not Available

1978-03-01T23:59:59.000Z

289

High-Temperature-High-Volume Lifting For Enhanced Geothermal Systems  

Open Energy Info (EERE)

Temperature-High-Volume Lifting For Enhanced Geothermal Systems Temperature-High-Volume Lifting For Enhanced Geothermal Systems Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title High-Temperature-High-Volume Lifting For Enhanced Geothermal Systems Project Type / Topic 1 Recovery Act: Enhanced Geothermal Systems Component Research and Development/Analysis Project Type / Topic 2 High-Temperature-High-Volume Lifting Project Description The proposed scope of work is divided into three Phases. Overall system requirements will be established in Phase 1, along with an evaluation of existing lifting system capability, identification of technology limitations, and a conceptual design of an overall lifting system. In developing the system components in Phase 2, component-level tests will be conducted using GE facilities. Areas of development will include high-temperature drive system materials, journal and thrust bearings, and corrosion and erosion-resistant lifting pump components. Finally, in Phase 3, the overall lab-scale lifting system will be demonstrated in a flow loop that will be constructed at GE Global Research.

290

Geothermal resources of the western arm of the Black Rock Desert, northwestern Nevada. Part I. Geology and geophysics  

DOE Green Energy (OSTI)

Studies of the geothermal potential of the western arm of the Black Rock Desert in northwestern Nevada included a compilation of existing geologic data on a detailed map, a temperature survey at 1-meter depth, a thermal-scanner survey, and gravity and seismic surveys to determine basin geometry. The temperature survey showed the effects of heating at shallow depths due to rising geothermal fluids near the known hot spring areas. Lower temperatures were noted in areas of probable near-surface ground-water movement. The thermal-scanner survey verified the known geothermal areas and showed relatively high-temperature areas of standing water and ground-water discharge. The upland areas of the desert were found to be distinctly warmer than the playa area, probably due to the low thermal diffusivity of upland areas caused by low moisture content. Surface geophysical surveys indicated that the maximum thickness of valley-fill deposits in the desert is about 3200 meters. Gravity data further showed that changes in the trend of the desert axis occurred near thermal areas. 53 refs., 8 figs., 3 tabs.

Schaefer, D.H.; Welch, A.H.; Maurer, D.K.

1983-01-01T23:59:59.000Z

291

The Newcastle geothermal system, Iron County, Utah  

DOE Green Energy (OSTI)

Geological, geophysical and geochemical studies contributed to conceptual hydrologic model of the blind'' (no surface expression), moderate-temperature (greater than 130{degree}C) Newcastle geothermal system, located in the Basin and Range-Colorado Plateau transition zone of southwestern Utah. Temperature gradient measurements define a thermal anomaly centered near the surface trace of the range-bounding Antelope Range fault with and elongate dissipative plume extending north into the adjacent Escalante Valley. Spontaneous potential and resistivity surveys sharply define the geometry of the dominant upflow zone (not yet explored), indicating that most of the thermal fluid issues form a short segment along the Antelope Range fault and discharges into a gently-dipping aquifer. Production wells show that this aquifer lies at a depth between 85 and 95 meter. Electrical surveys also show that some leakage of thermal fluid occurs over a 1.5 km (minimum) interval along the trace of the Antelope Range fault. Major element, oxygen and hydrogen isotopic analyses of water samples indicate that the thermal fluid is a mixture of meteoric water derived from recharge areas in the Pine Valley Mountains and cold, shallow groundwater. A northwest-southeast trending system of faults, encompassing a zone of increased fracture permeability, collects meteoric water from the recharge area, allows circulation to a depth of 3 to 5 kilometers, and intersects the northeast-striking Antelope Range fault. We postulate that mineral precipitates form a seal along the Antelope Range fault, preventing the discharge of thermal fluids into basin-fill sediments at depth, and allowing heated fluid to approach the surface. Eventually, continued mineral deposition could result in the development of hot springs at the ground surface.

Blackett, R.E.; Shubat, M.A.; Bishop, C.E. (Utah Geological and Mineral Survey, Salt Lake City, UT (USA)); Chapman, D.S.; Forster, C.B.; Schlinger, C.M. (Utah Univ., Salt Lake City, UT (USA). Dept. of Geology and Geophysics)

1990-03-01T23:59:59.000Z

292

Geothermal br Resource br Area Geothermal br Resource br Area Geothermal  

Open Energy Info (EERE)

Tectonic br Setting Host br Rock br Age Host br Rock br Lithology Tectonic br Setting Host br Rock br Age Host br Rock br Lithology Mean br Capacity Mean br Reservoir br Temp Amedee Geothermal Area Amedee Geothermal Area Walker Lane Transition Zone Geothermal Region Extensional Tectonics Mesozoic granite granodiorite MW K Beowawe Hot Springs Geothermal Area Beowawe Hot Springs Geothermal Area Central Nevada Seismic Zone Geothermal Region Extensional Tectonics MW K Blue Mountain Geothermal Area Blue Mountain Geothermal Area Northwest Basin and Range Geothermal Region Extensional Tectonics triassic metasedimentary MW K Brady Hot Springs Geothermal Area Brady Hot Springs Geothermal Area Northwest Basin and Range Geothermal Region Extensional Tectonics MW Coso Geothermal Area Coso Geothermal Area Walker Lane Transition Zone

293

Prospects for the commercial development of hot dry rock geothermal energy in New Mexico  

DOE Green Energy (OSTI)

A vast store of energy is available to the world in the form of hot dry rock (HDR) which exists almost everywhere beneath the surface of the earth. The Los Alamos National Laboratory has developed technology to mine the heat from HDR by using techniques developed in the petroleum industry. In practice, an artificial reservoir is created in the hot rock and water is circulated through the reservoir to extract the thermal energy and bring it to the surface. There are virtually no adverse environmental effects from an HDR plant when the system is operated in a closed-loop mode with the process water continually recirculated. An experimental plant at Fenton Hill, NM is now undergoing long-term testing to demonstrate that energy can be obtained from HDR on a sustained basis with operational procedures which are readily adaptable to industry. Significant HDR resources exist in the state of New Mexico. Resources in the Valles Caldera, Zuni Uplift, and Rio Grande Rift have been evaluated in detail. Studies indicate that it should be possible to economically develop high grade HDR resources with technology available today. As advanced concepts for developing and operating HDR systems are investigated, even more widespread utilization of the technology will be commercially feasible.

Duchane, D.V.; Goff, F.

1992-01-01T23:59:59.000Z

294

Geothermal Technologies | Open Energy Information  

Open Energy Info (EERE)

Print PDF Print PDF Geothermal Technologies Geothermal energy can be utilized for electricity or heating in more than one way. Regardless of the energy conversion, geothermal energy requires heat(in the form of rock), water, and flow; and every resources will have different values for each. Some resources have very high temperature rock with high porosity (allowing for flow) but little to know water (see Enhanced Geothermal Systems (EGS). Some resources have plenty of water, great flow, but the temperatures are not very high which are commonly used for direct use. Any combination of those 3 things can be found in nature, and for that reason there are different classifications of geothermal energy. It is possible for a resource to be technically capable of both electricity production and heating purposes, but the basic classifications

295

Geochemistry of thermal/mineral waters in the Clear Lake region, California, and implications for hot dry rock geothermal development  

DOE Green Energy (OSTI)

Thermal/mineral waters of the Clear Lake region are broadly classified as thermal meteoric and connote types based on chemical and isotopic criteria. Ratios of conservative components such as B/Cl are extremely different among all thermal/mineral waters of the Clear Lake region except for clusters of waters emerging from specific areas such as the Wilbur Springs district and the Agricultural Park area south of Mt. Konocti. In contrast, ratios of conservative components in large, homogeneous geothermal reservoirs are constant. Stable isotope values of Clear Lake region waters show a mixing trend between thermal meteoric and connote end-members. The latter end-member has enriched [delta]D as well as enriched d[sup l8]O, very different from typical high-temperature geothermal reservoir waters. Tritium data and modeling of ages indicate most Clear Lake region waters are 500 to > 10,000 yr., although mixing of old and young components is implied by the data. The age of end-member connate water is probably > 10,000 yr. Subsurface equilibration temperature of most thermal/mineral waters of the Clear Lake region is [le] 150[degrees]C based on chemical geothermometers but it is recognized that Clear Lake region waters are not typical geothermal fluids and that they violate rules of application of many geothermometers. The combined data indicate that no large geothermal reservoir underlies the Clear Lake region and that small localized reservoirs have equilibration temperatures [le] 150[degrees]C (except for Sulphur Bank Mine). Hot dry rock technologies are the best way to commercially exploit the known high temperatures existing beneath the Clear Lake region, particularly within the main Clear Lake volcanic field.

Goff, F.; Adams, A.I.; Trujillo, P.E.; Counce, D.; Mansfield, J.

1993-02-01T23:59:59.000Z

296

Property:Geothermal/Partner6Website | Open Energy Information  

Open Energy Info (EERE)

Partner6Website Partner6Website Jump to: navigation, search Property Name Geothermal/Partner6Website Property Type URL Description Partner 6 Website (URL) Pages using the property "Geothermal/Partner6Website" Showing 4 pages using this property. C Complete Fiber/Copper Cable Solution for Long-Term Temperature and Pressure Measurement in Supercritical Reservoirs and EGS Wells Geothermal Project + http://www.sensortran.com/ + I Innovative Exploration Techniques for Geothermal Assessment at Jemez Pueblo, New Mexico Geothermal Project + http://www.pitt.edu/ + S Seismic Technology Adapted to Analyzing and Developing Geothermal Systems Below Surface-Exposed High-Velocity Rocks Geothermal Project + http://www.sercel.com/ + T The Snake River Geothermal Drilling Project - Innovative Approaches to Geothermal Exploration Geothermal Project + http://www.icdp-online.org/contenido/icdp/front_content.php +

297

Hydrocarbon anomaly in soil gas as near-surface expressions of upflows and outflows in geothermal systems  

SciTech Connect

A variety of hydrocarbons, C1 - C12, have been found in volcanic gases (fumarolic) and in geothermal waters and gases. The hydrocarbons are thought to have come from products of pyrolysis of kerogen in sedimentary rocks or they could be fed into the geothermal system by the recharging waters which may contain dissolved hydrocarbons or hydrocarbons extracted by the waters from the rocks. In the hot geothermal zone, 300+ C, many of these hydrocarbons are in their critical state. It is thought that they move upwards due to buoyancy and flux up with the upflowing geothermal fluids in the upflow zones together with the magmatic gases. Permeability which could be provided by faults, fissures, mini and micro fractures are thought to provide pathways for the upward flux. A sensitive technique (Petrex) utilizing passive integrative adsorption of the hydrocarbons in soil gas on activated charcoal followed by desorption and analysis of the hydrocarbons by direct introduction mass spectrometry allows mapping of the anomalous areas. Surveys for geothermal resources conducted in Japan and in Indonesia show that the hydrocarbon anomaly occur over known fields and over areas strongly suspected of geothermal potential. The hydrocarbons found and identified were n-paraffins (C7-C9) and aromatics (C7-C8). Detection of permeable, i.e. active or open faults, parts of older faults which have been reactivated, e.g. by younger intersecting faults, and the area surrounding these faulted and permeable region is possible. The mechanism leading to the appearance of the hydrocarbon in the soil gas over upflow zones of the geothermal reservoir is proposed. The paraffins seems to be better pathfinders for the location of upflows than the aromatics. However the aromatics may, under certain circumstances, give better indications of the direction of the outflow of the geothermal system. It is thought that an upflow zone can be defined when conditions exist where the recharging waters containing the hydrocarbons feed into the geothermal kitchen. The existence of open and active faults, fissures, mini and micro fractures allow sufficient permeability for the gases to flux up and express themselves at the surface as hydrocarbon anomaly in the soil gas. When any of the requirements is absent, i.e. in the absence of the recharging waters, hydrocarbons, temperature, or permeability, no anomaly can be expected. It assumes a dynamic convective system, i.e. recharging waters, upflow and outflow. The anomalies however can define to a certain extent, regions of geothermal upflow, buoyant transport of gases, and frequently down-gradient of cooling waters.

Ong, H.L.; Higashihara, M.; Klusman, R.W.; Voorhees, K.J.; Pudjianto, R.; Ong, J

1996-01-24T23:59:59.000Z

298

Hydrocarbon anomaly in soil gas as near-surface expressions of upflows and outflows in geothermal systems  

Science Conference Proceedings (OSTI)

A variety of hydrocarbons, C1 - C12, have been found in volcanic gases (fumarolic) and in geothermal waters and gases. The hydrocarbons are thought to have come from products of pyrolysis of kerogen in sedimentary rocks or they could be fed into the geothermal system by the recharging waters which may contain dissolved hydrocarbons or hydrocarbons extracted by the waters from the rocks. In the hot geothermal zone, 300+ C, many of these hydrocarbons are in their critical state. It is thought that they move upwards due to buoyancy and flux up with the upflowing geothermal fluids in the upflow zones together with the magmatic gases. Permeability which could be provided by faults, fissures, mini and micro fractures are thought to provide pathways for the upward flux. A sensitive technique (Petrex) utilizing passive integrative adsorption of the hydrocarbons in soil gas on activated charcoal followed by desorption and analysis of the hydrocarbons by direct introduction mass spectrometry allows mapping of the anomalous areas. Surveys for geothermal resources conducted in Japan and in Indonesia show that the hydrocarbon anomaly occur over known fields and over areas strongly suspected of geothermal potential. The hydrocarbons found and identified were n-paraffins (C7-C9) and aromatics (C7-C8). Detection of permeable, i.e. active or open faults, parts of older faults which have been reactivated, e.g. by younger intersecting faults, and the area surrounding these faulted and permeable region is possible. The mechanism leading to the appearance of the hydrocarbon in the soil gas over upflow zones of the geothermal reservoir is proposed. The paraffins seems to be better pathfinders for the location of upflows than the aromatics. However the aromatics may, under certain circumstances, give better indications of the direction of the outflow of the geothermal system. It is thought that an upflow zone can be defined when conditions exist where the recharging waters containing the hydrocarbons feed into the geothermal kitchen. The existence of open and active faults, fissures, mini and micro fractures allow sufficient permeability for the gases to flux up and express themselves at the surface as hydrocarbon anomaly in the soil gas. When any of the requirements is absent, i.e. in the absence of the recharging waters, hydrocarbons, temperature, or permeability, no anomaly can be expected. It assumes a dynamic convective system, i.e. recharging waters, upflow and outflow. The anomalies however can define to a certain extent, regions of geothermal upflow, buoyant transport of gases, and frequently down-gradient of cooling waters.

Ong, H.L.; Higashihara, M.; Klusman, R.W.; Voorhees, K.J.; Pudjianto, R.; Ong, J

1996-01-24T23:59:59.000Z

299

Temporary Bridging Agents for use in Drilling and Completion of Enhanced Geothermal Systems  

Science Conference Proceedings (OSTI)

CSI Technologies, in conjunction with Alta Rock Energy and the University of Utah have undergone a study investigating materials and mechanisms with potential for use in Enhanced Geothermal Systems wells as temporary diverters or lost circulation materials. Studies were also conducted with regards to particle size distribution and sealing effectiveness using a lab-scale slot testing apparatus to simulate fractures. From the slot testing a numerical correlation was developed to determine the optimal PSD for a given fracture size. Field trials conducted using materials from this study were also successful.

Watters, Larry; Watters, Jeff; Sutton, Joy; Combs, Kyle; Bour, Daniel; Petty, Susan; Rose, Peter; Mella, Michael

2011-12-21T23:59:59.000Z

300

Higher-order differencing for front propagation in geothermal systems  

E-Print Network (OSTI)

and Renewable Energy, Geothermal Division, U.S. Departmentorder differencing for geothermal reservoir simulation,Proc. 22nd Workshop on Geothermal Reservoir Engineering,

Oldenburg, Curtis; Pruess, Karsten

1998-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rock geothermal systems" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

MATHEMATICAL MODELING OF THE BEHAVIOR OF GEOTHERMAL SYSTEMS UNDER EXPLOITATION  

E-Print Network (OSTI)

and momentum transfer i n a geothermal reservoir, Summaries2nd Work- shop Geothermal Reservoir Engineering, StanfordSchroeder, W e l l tests, Geothermal Resource and Reservoir

Bodvarsson, G.S.

2010-01-01T23:59:59.000Z

302

Economic impact of corrosion and scaling problems in geothermal energy systems  

SciTech Connect

Corrosion and scaling problems have a significant impact on geothermal plant economics. A power plant must amortize the capital investment over a 20-year period and achieve satisfactory operating efficiency to achieve financial success. Corrosion and scale incrustations have been encountered in all geothermal plants, and to various degrees, adversely affected plant life times and power output. Using published data this report analyzes known geothermal corrosion and scaling phenomena for significant cost impacts on plant design and operation. It has been necessary to speculate about causes and mechanisms in order to estimate impacts on conceptual geothermal plants. Silica is highly soluble in hot geothermal water and solubility decreases as water is cooled in a geothermal power plant. Calculations indicate as much as 30,000 tons/year could pass through a 100 MWe water cycle plant. The major cost impact will be on the reinjection well system where costs of 1 to 10 mills/kwhr of power produced could accrue to waste handling alone. On the other hand, steam cycle geothermal plants have a definite advantage in that significant silica problems will probably only occur in hot dry rock concepts, where steam above 250 C is produced. Calculation methods are given for estimating the required size and cost impact of a silica filtration plant and for sizing scrubbers. The choice of materials is significantly affected by the pH of the geothermal water, temperature, chloride, and H{sub s} contents. Plant concepts which attempt to handle acid waters above 180 C will be forced to use expensive corrosion resistant alloys or develop specialized materials. On the other hand, handling steam up to 500 C, and pH 9 water up to 180 C appears feasible using nominal cost steels, typical of today's geothermal plants. A number of factors affecting plant or component availability have been identified. The most significant is a corrosion fatigue problem in geothermal turbines at the Geyser's geothermal plant which is presently reducing plant output by about 10%. This is equivalent to over $3 million per year in increased oil consumption to replace the power. In the course of assessing the cost implications of corrosion and scaling problems, a number of areas of technological uncertainty were identified which should be considered in R and D planning in support of geothermal energy. Materials development with both laboratory and field testing will be necessary. The economic analysis on which this report is based was done in support of an AEC Division of Applied Technology program to assess the factors affecting geothermal plant economics. The results of this report are to be used to develop computer models of overall plant economics, of which corrosion and scaling problems are only a part. The translation of the economic analysis to the report which appears here, was done on AEC Special Studies Funds.

Shannon, D.W.

1975-01-01T23:59:59.000Z

303

Economic impact of corrosion and scaling problems in geothermal energy systems  

DOE Green Energy (OSTI)

Corrosion and scaling problems have a significant impact on geothermal plant economics. A power plant must amortize the capital investment over a 20-year period and achieve satisfactory operating efficiency to achieve financial success. Corrosion and scale incrustations have been encountered in all geothermal plants, and to various degrees, adversely affected plant life times and power output. Using published data this report analyzes known geothermal corrosion and scaling phenomena for significant cost impacts on plant design and operation. It has been necessary to speculate about causes and mechanisms in order to estimate impacts on conceptual geothermal plants. Silica is highly soluble in hot geothermal water and solubility decreases as water is cooled in a geothermal power plant. Calculations indicate as much as 30,000 tons/year could pass through a 100 MWe water cycle plant. The major cost impact will be on the reinjection well system where costs of 1 to 10 mills/kwhr of power produced could accrue to waste handling alone. On the other hand, steam cycle geothermal plants have a definite advantage in that significant silica problems will probably only occur in hot dry rock concepts, where steam above 250 C is produced. Calculation methods are given for estimating the required size and cost impact of a silica filtration plant and for sizing scrubbers. The choice of materials is significantly affected by the pH of the geothermal water, temperature, chloride, and H{sub s} contents. Plant concepts which attempt to handle acid waters above 180 C will be forced to use expensive corrosion resistant alloys or develop specialized materials. On the other hand, handling steam up to 500 C, and pH 9 water up to 180 C appears feasible using nominal cost steels, typical of today's geothermal plants. A number of factors affecting plant or component availability have been identified. The most significant is a corrosion fatigue problem in geothermal turbines at the Geyser's geothermal plant which is presently reducing plant output by about 10%. This is equivalent to over $3 million per year in increased oil consumption to replace the power. In the course of assessing the cost implications of corrosion and scaling problems, a number of areas of technological uncertainty were identified which should be considered in R and D planning in support of geothermal energy. Materials development with both laboratory and field testing will be necessary. The economic analysis on which this report is based was done in support of an AEC Division of Applied Technology program to assess the factors affecting geothermal plant economics. The results of this report are to be used to develop computer models of overall plant economics, of which corrosion and scaling problems are only a part. The translation of the economic analysis to the report which appears here, was done on AEC Special Studies Funds.

Shannon, D.W.

1975-01-01T23:59:59.000Z

304

Utilization of melting techniques for borehole wall stabilization. [Applied to geothermal well production systems  

DOE Green Energy (OSTI)

A research program on the Subterrene concept based on excavation by melting has been completed. Theoretical and experimental studies were made for a broad range of applications. Most recently, a study of Subterrene deep geothermal well production systems predicted that, compared to rotary-drilled wells, significant cost savings are possible, e.g., 2 and 4 million dollars for 10-km-deep wells and geothermal gradients of 25 and 40 K/km, respectively. It was also concluded that for most wells the rate of penetration of the melting bits should be increased several times over that attained in the Subterrene tests. Subterrene melting penetration tests showed that borehole glass liners can be formed in a wide variety of materials and structural characterization tests showed that tuff glass cylinders can be many times stronger in compression than the parent material. Also, the tests showed that the rock-glass liner permeability decreases rapidly with confining pressure. New melting devices are conceivable that could line rotary-drilled boreholes with rock glass or other materials with resultant improvements in well costs. With emphasis on borehole liners, an overview of Subterrene program results, data on rock-glass liners, and suggestions on how molten materials might be applied to the borehole wall as part of a rotary drilling operation are presented.

Altseimer, J.H.

1977-01-01T23:59:59.000Z

305

The conversion of biomass to ethanol using geothermal energy derived from hot dry rock to supply both the thermal and electrical power requirements  

SciTech Connect

The potential synergism between a hot dry rock (HDR) geothermal energy source and the power requirements for the conversion of biomass to fuel ethanol is considerable. In addition, combining these two renewable energy resources to produce transportation fuel has very positive environmental implications. One of the distinct advantages of wedding an HDR geothermal power source to a biomass conversion process is flexibility, both in plant location and in operating process is flexibility, both in plant location and in operating conditions. The latter obtains since an HDR system is an injection conditions of flow rate, pressure, temperature, and water chemistry are under the control of the operator. The former obtains since, unlike a naturally occurring geothermal resource, the HDR resource is very widespread, particularly in the western US, and can be developed near transportation and plentiful supplies of biomass. Conceptually, the pressurized geofluid from the HDR reservoir would be produced at a temperature in the range of 200{degrees} to 220{degrees}c. The higher enthalpy portion of the geofluid thermal energy would be used to produce a lower-temperature steam supply in a countercurrent feedwater-heater/boiler. The steam, following a superheating stage fueled by the noncellulosic waste fraction of the biomass, would be expanded through a turbine to produce electrical power. Depending on the lignin fraction of the biomass, there would probably be excess electrical power generated over and above plant requirements (for slurry pumping, stirring, solids separation, etc.) which would be available for sale to the local power grid. In fact, if the hybrid HDR/biomass system were creatively configured, the power plant could be designed to produce daytime peaking power as well as a lower level of baseload power during off-peak hours.

Brown, D.W.

1997-10-01T23:59:59.000Z

306

Residential Vertical Geothermal Heat Pump System Models: Calibration to Data:  

SciTech Connect

A detailed component-based simulation model of a geothermal heat pump system has been calibrated to monitored data taken from a family housing unit located at Fort Polk, Louisiana. The simulation model represents the housing unit, geothermal heat pump, ground heat exchanger, thermostat, blower, and ground-loop pump. Each of these component models was 'tuned' to better match the measured data from the site. These tuned models were then interconnect to form the system model. The system model was then exercised in order to demonatrate its capabilities.

Thornton, Jeff W. [Thermal Energy Systems Specialists, Inc.; McDowell, T. P. [Thermal Energy Systems Specialists, Inc.; Shonder, John A [ORNL; Hughes, Patrick [ORNL; Pahud, D. [University of Applied Sciences of Southern Switzerland; Hellstrom, G. [Lund University

1997-06-01T23:59:59.000Z

307

Environmental impact directory system: preliminary implementation for geothermal energy  

DOE Green Energy (OSTI)

An Environmental Impact Directory System (EIDS) was proposed as a method for a computerized search of the widely distributed data files and models pertaining to energy-related environmental effects. To define the scope and content of the system, an example was prepared for the case of geothermal energy. The resulting sub-directory is known as GEIDs (Geothermal Environmental Impact Directory System). In preparing or reviewing an Environmental Impact Statement (EIS), the user may employ GEIDS as an extensive checklist to make sure he has taken into account all predictable impacts at any level of severity.

Hess, F.D.; Hall, R.T.; Fullenwider, E.D.

1976-07-01T23:59:59.000Z

308

Beneficial effects of groundwater entry into liquid-dominated geothermal systems  

DOE Green Energy (OSTI)

In all active liquid-dominated geothermal systems there is continuous circulation of mass and transfer of heat, otherwise they would slowly cool and fade away. In the natural state these systems are in dynamic equilibrium with the surrounding colder groundwater aquifers. The ascending geothermal fluids cool conductively, boil, or mix with groundwaters, and ultimately may discharge at the surface as fumaroles or hot springs. With the start of fluid production and the lowering of reservoir pressure, the natural equilibrium is disrupted and cooler groundwater tends to enter the reservoir. Improperly constructed or damaged wells, and wells located near the margins of the geothermal system, exhibit temperature reductions (and possibly scaling from mixing of chemically distinct fluids) as the cooler-water moves into the reservoir. These negative effects, especially in peripheral wells are, however, compensated by the maintenance of reservoir pressure and a reduction in reservoir boiling that might result in mineral precipitation in the formation pores and fractures. The positive effect of cold groundwater entry on the behavior of liquid-dominated system is illustrated by using simple reservoir models. The simulation results show that even though groundwater influx into the reservoir causes cooling of fluids produced from wells located near the cold-water recharge area, it also reduces pressure drawdown and boiling in the exploited zone, and sweeps the heat stored in the reservoir rocks toward production wells, thus increasing the productive life of the wells and field. 9 refs.

Lippmann, M.J. (Lawrence Berkeley Lab., CA (USA)); Truesdell, A.H. (Geological Survey, Menlo Park, CA (USA))

1990-04-01T23:59:59.000Z

309

Category:Geothermal Technologies | Open Energy Information  

Open Energy Info (EERE)

Geothermal Systems (EGS) G Geothermal Direct Use G cont. GeothermalExploration Ground Source Heat Pumps H Hydrothermal System S Sedimentary Geothermal Systems Retrieved from...

310

Rock failure during massive hydraulic stimulation of the Baca location geothermal reservoir  

DOE Green Energy (OSTI)

The analyses of microearthquake signals occurring during hydraulic stimulation provide an estimate of the size and location of the fractures thus produced. Studies of microearthquakes occurring during two large (> 10/sup 3/m/sup 3/) hydraulic stimulations of the hydrothermal reservoir at the Baca Location in the Jemez Mountains of northeastern New Mexico are reported. Both stimulations consisted of water, viscosity enhancer, and proppant. The microearthquake event rate was low but variable throughout most of the treatment. Rock failure as indicated by the distribution of the microearthquakes' foci appeared restricted to a nearly vertical NE striking zone. This orientation is in good agreement with the local earth stresses inferred from geological considerations. The second stimulation which occurred in a neighboring well was similar to the first except for a larger injected volume. The lateral extent of the detected fracture system was 600 m in both stimulations.

Pearson, C.; Keppler, H.; Albright, J.; Potter, R.

1982-01-01T23:59:59.000Z

311

Geology and alteration of the Raft River geothermal system, Idaho | Open  

Open Energy Info (EERE)

alteration of the Raft River geothermal system, Idaho alteration of the Raft River geothermal system, Idaho Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: Geology and alteration of the Raft River geothermal system, Idaho Details Activities (1) Areas (1) Regions (0) Abstract: analcime; Cassia County Idaho; Cenozoic; chlorite; chlorite group; clay minerals; economic geology; exploration; framework silicates; geothermal energy; Idaho; illite; kaolinite; laumontite; montmorillonite; Neogene; Precambrian; Raft Formation; Raft River KGRA; Salt Lake Formation; sheet silicates; silicates; Tertiary; United States; wairakite; wells; zeolite group Author(s): Blackett, R.E.; Kolesar, P.T. Published: Geothermal Resource Council Transactions 1983, 1/1/1983 Document Number: Unavailable DOI: Unavailable

312

Evaluation of C-14 as a natural tracer for injected fluids at the Aidlin sector of The Geysers geothermal system through modeling of mineral-water-gas Reactions  

E-Print Network (OSTI)

breakthrough observed in geothermal systems (e.g. , Shook,recharge project, Geysers geothermal field, California, USA,media: Applications to geothermal injectivity and CO 2

Dobson, Patrick; Sonnenthal, Eric; Lewicki, Jennifer; Kennedy, Mack

2006-01-01T23:59:59.000Z

313

Enhanced geothermal systems (EGS) with CO2 as heat transmission fluid--A scheme for combining recovery of renewable energy with geologic storage of CO2  

E-Print Network (OSTI)

Interactions in Enhanced Geothermal Systems (EGS) with CO 2Fluid, Proceedings, World Geothermal Congress 2010, Bali,Remain? Transactions, Geothermal Resources Council, Vol. 17,

Pruess, K.

2010-01-01T23:59:59.000Z

314

Strategies for Detecting Hidden Geothermal Systems by Near-Surface Gas Monitoring  

E-Print Network (OSTI)

Propulsion Laboratory, National Rev. 1.2 Strategies for Detection of Hidden Geothermal Systems Aeronautics and Space

Lewicki, Jennifer L.; Oldenburg, Curtis M.

2004-01-01T23:59:59.000Z

315

Geothermal programs at Lawrence Livermore National Laboratory  

DOE Green Energy (OSTI)

Lawrence Livermore National Laboratory has a number of geothermal programs supported through two offices in the Department of Energy: the Office of Renewable Technologies, Geothermal Technologies Division, and the Office of Basic Energy Sciences, Division of Engineering, Mathematics and Geosciences. Within these programs, we are carrying out research in injection monitoring, optical instrumentation for geothermal wells, seismic imaging methods, geophysical and drilling investigations of young volcanic systems in California, and fundamental studies of the rock and mineral properties.

Kasameyer, P.W.; Younker, L.W.

1987-07-10T23:59:59.000Z

316

Progress Toward an Advanced Geothermal Deep-Drilling System  

DOE Green Energy (OSTI)

A previously developed concept for an advanced geothermal drilling system (AGDS) has been extended toward a feasibility design stage. Hardware projects for two percussion, air and hydraulic, hammer drills are underway. Two drill string options and an unique nitrogen supply system are described.

Rowley, J.; Saito, S.; Long, R.

1995-01-01T23:59:59.000Z

317

Recommendations of the workshop on advanced geothermal drilling systems  

DOE Green Energy (OSTI)

At the request of the U.S. Department of Energy, Office of Geothermal Technologies, Sandia National Laboratories convened a group of drilling experts in Berkeley, CA, on April 15-16, 1997, to discuss advanced geothermal drilling systems. The objective of the workshop was to develop one or more conceptual designs for an advanced geothermal drilling system that meets all of the criteria necessary to drill a model geothermal well. The drilling process was divided into ten essential functions. Each function was examined, and discussions were held on the conventional methods used to accomplish each function and the problems commonly encountered. Alternative methods of performing each function were then listed and evaluated by the group. Alternative methods considered feasible or at least worth further investigation were identified, while methods considered impractical or not potentially cost-saving were eliminated from further discussion. This report summarizes the recommendations of the workshop participants. For each of the ten functions, the conventional methods, common problems, and recommended alternative technologies and methods are listed. Each recommended alternative is discussed, and a description is given of the process by which this information will be used by the U.S. DOE to develop an advanced geothermal drilling research program.

Glowka, D.A.

1997-12-01T23:59:59.000Z

318

Enhanced heat extraction from hot-dry-rock geothermal reservoirs due to interacting secondary thermal cracks. Final report  

DOE Green Energy (OSTI)

How the fluid circulating through the main hydraulic fracture and the thermally-induced secondary, growing, interacting cracks affects the time-varying temperature, deformations, stresses, thermal crack geometry, water flow rates through the main and thermal cracks, reservoir coolant outlet temperature, and reservoir thermal power of the cracked geothermal reservoir is investigated. First, a simplified version of the proposed hot-dry-rock reservoir is considered. A closed-form solution of the rock temperature without thermal crack was found and substituted into SAP-IV computer code to calculate the stresses. These stresses being superposed with earth stresses and fluid pressure were used in conjunction with the fracture mechanics criterion to determine the initiation of secondary thermal crack. After the initiation of secondary thermal crack, the rock temperature was then calculated by a two-dimensional heat conduction program AYER. The detailed procedures for carrying out these steps are listed. Solutions developed are applied to studying the time-varying temperature field, thermal stresses and crack geometry produced, and additional heat power generated in the reservoir. Conclusions were discussed and summarized. (MHR)

Hsu, Y.C.

1979-04-01T23:59:59.000Z

319

Geothermal System Saves Dollars, Makes Sense for Maryland Family |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

System Saves Dollars, Makes Sense for Maryland Family System Saves Dollars, Makes Sense for Maryland Family Geothermal System Saves Dollars, Makes Sense for Maryland Family April 16, 2010 - 5:15pm Addthis A 36-foot-tall drill was needed to install the geothermal system at the Gearon’s house in Derwood, MD. | Photo courtesy of Chris Gearon | A 36-foot-tall drill was needed to install the geothermal system at the Gearon's house in Derwood, MD. | Photo courtesy of Chris Gearon | Lindsay Gsell "At the end of the day, it cost us about the same as if we just replaced our furnace and AC with another furnace and AC, but the big difference is that we're not spending $3,000 on oil bills anymore." Chris Gearon, Derwood, MD resident who recently installed a geothermal system to heal and cool his home Chris Gearon's 24-year old oil furnace was tired. What happened if the

320

Insights From Laboratory Experiments On Simulated Faults With Application To Fracture Evolution In Geothermal Systems  

Science Conference Proceedings (OSTI)

Laboratory experiments provide a wealth of information related to mechanics of fracture initiation, fracture propagation processes, factors influencing fault strength, and spatio-temporal evolution of fracture properties. Much of the existing literature reports on laboratory studies involving a coupling of thermal, hydraulic, mechanical, and/or chemical processes. As these processes operate within subsurface environments exploited for their energy resource, laboratory results provide insights into factors influencing the mechanical and hydraulic properties of geothermal systems. I report on laboratory observations of strength and fluid transport properties during deformation of simulated faults. The results show systematic trends that vary with stress state, deformation rate, thermal conditions, fluid content, and rock composition. When related to geophysical and geologic measurements obtained from engineered geothermal systems (e.g. microseismicity, wellbore studies, tracer analysis), laboratory results provide a means by which the evolving thermal reservoir can be interpreted in terms of physico-chemical processes. For example, estimates of energy release and microearthquake locations from seismic moment tensor analysis can be related to strength variations observed from friction experiments. Such correlations between laboratory and field data allow for better interpretations about the evolving mechanical and fluid transport properties in the geothermal reservoir ultimately leading to improvements in managing the resource.

Stephen L. Karner, Ph.D

2006-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "rock geothermal systems" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Geochemical Enhancement Of Enhanced Geothermal System Reservoirs: An Integrated Field And Geochemical Approach  

DOE Green Energy (OSTI)

The geochemical effects of injecting fluids into geothermal reservoirs are poorly understood and may be significantly underestimated. Decreased performance of injection wells has been observed in several geothermal fields after only a few years of service, but the reasons for these declines has not been established. This study had three primary objectives: 1) determine the cause(s) of the loss of injectivity; 2) utilize these observations to constrain numerical models of water-rock interactions; and 3) develop injection strategies for mitigating and reversing the potential effects of these interactions. In this study rock samples from original and redrilled injection wells at Coso and the Salton Sea geothermal fields, CA, were used to characterize the mineral and geochemical changes that occurred as a result of injection. The study documented the presence of mineral scales and at both fields in the reservoir rocks adjacent to the injection wells. At the Salton Sea, the scales consist of alternating layers of fluorite and barite, accompanied by minor anhydrite, amorphous silica and copper arsenic sulfides. Amorphous silica and traces of calcite were deposited at Coso. The formation of silica scale at Coso provides an example of the effects of untreated (unacidified) injectate on the reservoir rocks. Scanning electron microscopy and X-ray diffractometry were used to characterize the scale deposits. The silica scale in the reservoir rocks at Coso was initially deposited as spheres of opal-A 1-2 micrometers in diameter. As the deposits matured, the spheres coalesced to form larger spheres up to 10 micrometer in diameter. Further maturation and infilling of the spaces between spheres resulted in the formation of plates and sheets that substantially reduce the original porosity and permeability of the fractures. Peripheral to the silica deposits, fluid inclusions with high water/gas ratios provide a subtle record of interactions between the injectate and reservoir rocks. In contrast, fluid inclusions trapped prior to injection are relatively gas rich. These results suggest that the rocks undergo extensive microfracturing during injection and that the composition of the fluid inclusions will be biased toward the youngest event. Interactions between the reservoir rocks and injectate were modeled using the non-isothermal reactive geochemical transport code TOUGHREACT. Changes in fluid pH, fracture porosity, fracture permeability, fluid temperature, and mineral abundances were monitored. The simulations predict that amorphous silica will precipitate primarily within a few meters of the injection well and that mineral deposition will lead to rapid declines in fracture porosity and permeability, consistent with field observations. In support of Enhanced Geothermal System development, petrologic studies of Coso well 46A-19RD were conducted to determine the regions that are most likely to fail when stimulated. These studies indicate that the most intensely brecciated and altered rocks in the zone targeted for stimulation (below 10,000 ft (3048 m)) occur between 11,200 and 11,350 ft (3414 and 3459 m). This zone is interpreted as a shear zone that initially juxtaposed quartz diorite against granodiorite. Strong pervasive alteration and veining within the brecciated quartz diorite and granodiorite suggest this shear zone was permeable in the past. This zone of weakness was subsequently exploited by a granophyre dike whose top occurs at 11,350 ft (3459 m). The dike is unaltered. We anticipate, based on analysis of the well samples that failure during stimulation will most likely occur on this shear zone.

Joseph N. Moore

2007-12-31T23:59:59.000Z

322

Environmental monitoring for the hot dry rock geothermal energy development project. Annual report, July 1975--June 1976  

DOE Green Energy (OSTI)

The objectives of this environmental monitoring report are to provide a brief conceptual and historical summary of the Hot Dry Rock Geothermal Project, a brief overview of the environmental monitoring responsibilities and activities of the Los Alamos Scientific Laboratory, and descriptions of the studies, problems, and results obtained from the various monitoring programs. Included are descriptions of the work that has been done in three major monitoring areas: (1) water quality, both surface and subsurface; (2) seismicity, with a discussion of the monitoring strategy of regional, local, and close-in detection networks; and (3) climatology. The purpose of these programs is to record baseline data, define potential effects from the project activities, and determine and record any impacts that may occur.

Pettitt, R.A. (comp.)

1976-09-01T23:59:59.000Z

323

Dual-temperature Kalina cycle for geothermal-solar hybrid power systems  

E-Print Network (OSTI)

This thesis analyzes the thermodynamics of a power system coupling two renewable heat sources: low-temperature geothermal and a high-temperature solar. The process, referred to as a dual-temperature geothermal-solar Kalina ...

Boghossian, John G

2011-01-01T23:59:59.000Z

324

Modeling and analysis of hybrid geothermal-solar thermal energy conversion systems  

E-Print Network (OSTI)

Innovative solar-geothermal hybrid energy conversion systems were developed for low enthalpy geothermal resources augmented with solar energy. The goal is to find cost-effective hybrid power cycles that take advantage of ...

Greenhut, Andrew David

2010-01-01T23:59:59.000Z

325

Geothermal Energy Program overview  

SciTech Connect

The mission of the Geothermal Energy Program is to develop the science and technology necessary for tapping our nation's tremendous heat energy sources contained with the Earth. Geothermal energy is a domestic energy source that can produce clean, reliable, cost- effective heat and electricity for our nation's energy needs. Geothermal energy -- the heat of the Earth -- is one of our nation's most abundant energy resources. In fact, geothermal energy represents nearly 40% of the total US energy resource base and already provides an important contribution to our nation's energy needs. Geothermal energy systems can provide clean, reliable, cost-effective energy for our nation's industries, businesses, and homes in the form of heat and electricity. The US Department of Energy's (DOE) Geothermal Energy Program sponsors research aimed at developing the science and technology necessary for utilizing this resource more fully. Geothermal energy originates from the Earth's interior. The hottest fluids and rocks at accessible depths are associated with recent volcanic activity in the western states. In some places, heat comes to the surface as natural hot water or steam, which have been used since prehistoric times for cooking and bathing. Today, wells convey the heat from deep in the Earth to electric generators, factories, farms, and homes. The competitiveness of power generation with lower quality hydrothermal fluids, geopressured brines, hot dry rock, and magma ( the four types of geothermal energy) still depends on the technical advancements sought by DOE's Geothermal Energy Program.

1991-12-01T23:59:59.000Z

326

Geothermal Reservoir Dynamics - TOUGHREACT  

DOE Green Energy (OSTI)

This project has been active for several years and has focused on developing, enhancing and applying mathematical modeling capabilities for fractured geothermal systems. The emphasis of our work has recently shifted towards enhanced geothermal systems (EGS) and hot dry rock (HDR), and FY05 is the first year that the DOE-AOP actually lists this project under Enhanced Geothermal Systems. Our overall purpose is to develop new engineering tools and a better understanding of the coupling between fluid flow, heat transfer, chemical reactions, and rock-mechanical deformation, to demonstrate new EGS technology through field applications, and to make technical information and computer programs available for field applications. The objectives of this project are to: (1) Improve fundamental understanding and engineering methods for geothermal systems, primarily focusing on EGS and HDR systems and on critical issues in geothermal systems that are difficult to produce. (2) Improve techniques for characterizing reservoir conditions and processes through new modeling and monitoring techniques based on ''active'' tracers and coupled processes. (3) Improve techniques for targeting injection towards specific engineering objectives, including maintaining and controlling injectivity, controlling non-condensable and corrosive gases, avoiding scale formation, and optimizing energy recovery. Seek opportunities for field testing and applying new technologies, and work with industrial partners and other research organizations.

Pruess, Karsten; Xu, Tianfu; Shan, Chao; Zhang, Yingqi; Wu,Yu-Shu; Sonnenthal, Eric; Spycher, Nicolas; Rutqvist, Jonny; Zhang,Guoxiang; Kennedy, Mack

2005-03-15T23:59:59.000Z

327

Hot Dry Rock Geothermal Energy Development Program. Annual report, fiscal year 1983  

DOE Green Energy (OSTI)

Emphasis was on hydraulic-fracturing experiments at depths around 3.5 km (11,473 ft) in the two inclined wells of the Phase II system at Fenton Hill, New Mexico; on improved facilities and techniques for mapping the source locations of acoustic signals generated by the fracturing events; on mathematical modeling of the fracture systems produced in these and earlier experiments; and on development of a family of slimline high-temperature downhole instruments that can be used within or through relatively small-diameter pressure tubing. Hydraulic fracturing at a vertical depth of approximately 3500 m (11,500 ft) in well EE-2, the deeper well, produced fractures that, in acoustic maps, appear to occupy a large, roughly ellipsoidal volume whose major axis is directed to the north of the other well, EE-3. Hydraulic fracturing from EE-3 at a similar depth produced another set of fractures that appear to be approximately parallel to and centered about 180 m (600 ft) east of the earlier set. Subsequent fluid injections reduced the distance between the two sets, but no hydraulic connection between them was established. Modeling the silica concentrations of fluid circulated through the earlier Phase I system indicates that this type of permeation also contributes significantly to heat extraction during system operation. The precision and accuracy of locating the sources of acoustic signals detected during hydraulic-fracturing operations have been increased by improvements in equipment, drilling of another deep hole for geophone emplacement, and additional station calibrations. Analysis of the signals has also been improved and broadened. Development of slimline downhole instruments has included a detonator tool, a geophone package, and final design of a high-temperature borehole acoustic televiewer. A crosswell acoustic transceiver has also been developed for investigating rock type and structure between wellbores. 32 refs., 35 figs.

Smith, M.C.; Nunz, G.J.; Wilson, M.G. (comps.)

1985-02-01T23:59:59.000Z

328

Geologic and hydrologic research on the Moana geothermal system, Washoe County, Nevada. Final report October 1, 1982-December 31, 1983  

DOE Green Energy (OSTI)

Combined geologic, geophysical, geochemical, and drilling exploration surveys were used to assess the Moana geothermal resource in Washoe County, Nevada, and to determine its relationship with nearby Steamboat Hot Springs. Moana is the largest single moderate-temperature resource in Nevada that supports geothermal space heating applications. Results show that the general geology and structure for the two systems is similar, but important differences exist with respect to reservoir rocks. Gravity data delineated the contact between important volcanic and sedimentary rocks in Moana, but contour trends did not correlate well with mapped faults. Fluid geochemistry data show major differences in bulk chemical composition, stable-light isotope ratios, and radiocarbon ages for Moana and Steamboat geothermal waters. Water level measurements in observation wells in Moana show simultaneous increasing and decreasing values in different sections of the geothermal area. Temperature-depth profiles changed little during the six-month monitoring period. Direct use of the resource is increasing and longer-lasting, more efficient down-hole heat exchangers are replacing previous equipment that was prone to scaling and corrosion. A computer program that calculates heat output for state-of-the-art heat exchangers is described. Recommendations for continued monitoring, heat exchanger design, and fluid reinjection studies are included. Data are available to government agencies responsible for regulation as well as local residents and potential developers to ensure prudent resource utilization.

Flynn, T.; Ghusn, G. Jr.

1984-01-01T23:59:59.000Z

329

Analysis of Power Cycles for Geothermal Wellhead Conversion Systems  

Science Conference Proceedings (OSTI)

Using the guidelines and data developed from 240 representative cases, utility engineers can make preliminary estimates of the performance of alternative energy conversion systems proposed for specific geothermal sites. This approach can reduce the cost and scope of initial engineering studies.

1985-06-14T23:59:59.000Z

330

Description and operation of Haakon School geothermal-heating system  

SciTech Connect

To encourage the development of hydrothermal energy, twenty-three demonstration projects were funded. The Haakon School project is one of twelve such projects. The geothermal direct-use heating system at the Haakon School complex in Philip, South Dakota is described and information gained during approximately three heating seasons of operation is presented.

Childs, F.W.; Kirol, L.D.; Sanders, R.D.; McLatchy, M.J.

1983-10-01T23:59:59.000Z

331

Hot dry rock geothermal energy development program. Annual report, fiscal year 1982  

DOE Green Energy (OSTI)

Emphasis in the Hot Dry Rock Program was on development of methods to produce the hydraulic fractures required to connect the deep, inclined wells of the Phase II system at Fenton Hill. Environmental surveillance, instrument development, laboratory and modeling studies, and other supporting activities were continued. After two unsuccessful attempts to fracture hydraulically through inflatable packers, formation breakdown was produced in an uncased section near the bottom of well EE-2 by pumping water through a cemented-in steel liner. Breakdon occurred at a wellhead pressure of 33.1 MPa and a total of 8539 m/sup 3/ of water was injected. Mapping of source locations of microseismic events indicated opening of an extensive set of planar features dipping about 40/sup 0/W, striking about N20/sup 0/W, and apparently passing beneath the bottom of well EE-3. An attempt was then made to fracture at a higher level where the relative positions of the two wells increased the probability that an inclined fracture would connect them. Repeated failures of drill pipe, tubing, couplings, and packers terminated most pumping experiments prematurely. Important advances were made in thermal protection of downhole instruments, real-time mapping source locations of microseismic signals, modeling of heat and mass transport, and the mechanics of hydraulic fracturing.

Smith, M.C.; Nunz, G.J.; Ponder, G.M. (eds.)

1983-09-01T23:59:59.000Z

332

Enhanced Geothermal Systems (EGS) with CO2 as Heat Transmission Fluid  

Open Energy Info (EERE)

with CO2 as Heat Transmission Fluid with CO2 as Heat Transmission Fluid Geothermal Lab Call Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Enhanced Geothermal Systems (EGS) with CO2 as Heat Transmission Fluid Project Type / Topic 1 Laboratory Call for Submission of Applications for Research, Development and Analysis of Geothermal Technologies Project Type / Topic 2 Supercritical Carbon Dioxide / Reservoir Rock Chemical Interactions Project Description Previous and current attempts to develop EGS in the U.S., Japan, Europe and Australia have all employed water as a heat transmission fluid. Water has many properties that make it a favorable medium for heat extraction, but it also has serious drawbacks. The use of supercritical CO2 (scCO2) instead of water as heat extraction fluid was suggested by Donald Brown of Los Alamos National Laboratory as a "game changing" alternative that can avoid the problems of aqueous fluids, make heretofore inaccessible energy resources available for human use, and provide ancillary benefits by using and storing CO2.

333

Fluid origin, gas fluxes and plumbing system in the sediment-hosted Salton Sea Geothermal System (California, USA)  

E-Print Network (OSTI)

Fluid origin, gas fluxes and plumbing system in the sediment-hosted Salton Sea Geothermal System Available online 12 June 2011 Keywords: Salton Sea Geothermal System hydrothermal seeps gas and water geochemistry flux measurements mantle The Salton Sea Geothermal System (California) is an easily accessible

Mazzini, Adriano

334

Strategies For Detecting Hidden Geothermal Systems By Near-Surface Gas  

Open Energy Info (EERE)

Strategies For Detecting Hidden Geothermal Systems By Near-Surface Gas Strategies For Detecting Hidden Geothermal Systems By Near-Surface Gas Monitoring Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report: Strategies For Detecting Hidden Geothermal Systems By Near-Surface Gas Monitoring Details Activities (6) Areas (1) Regions (0) Abstract: Hidden geothermal systems are those systems above which hydrothermal surface features (e.g., hot springs, fumaroles, elevated ground temperatures, hydrothermal alteration) are lacking. Emissions of moderate to low solubility gases (e.g., CO2, CH4, He) may be one of the primary near-surface signals from these systems. Detection of anomalous gas emissions related to hidden geothermal systems may therefore be an important tool to discover new geothermal resources. This study investigates the potential for CO2 detection and monitoring in the

335

Seismological investigation of crack formation in hydraulic rock fracturing experiments and in natural geothermal environments. Progress report, September 1, 1980-August 31, 1981  

DOE Green Energy (OSTI)

Progress is reported on the following: interpretation of seismic data from hydraulic fracturing experiments at the Fenton Hill Hot Dry Rock Geothermal Site, interpretation of 3-D velocity anomalies in the western US with special attention to geothermal areas, theoretical and observational studies of scattering and attenuation of high-frequency seismic waves, theoretical and observational studies of volcanic tremors in relation to magma transport mechanisms, and deployment and maintenance of 9 event-recorders around Mt. St. Helens. Abstracts of papers submitted for publication are included. (MHR)

Aki, K.

1981-09-01T23:59:59.000Z

336

Isotopic Analysis Fluid At Coso Geothermal Area (1997) | Open Energy  

Open Energy Info (EERE)

Fluid At Coso Geothermal Area (1997) Fluid At Coso Geothermal Area (1997) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis- Fluid At Coso Geothermal Area (1997) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Isotopic Analysis- Fluid Activity Date 1997 Usefulness not indicated DOE-funding Unknown Exploration Basis Identify the source of chlorine Notes The 36Cl/Cl values for several geothermal water samples and reservoir host rock samples have been measured. The results suggest that the thermal waters could be connate waters derived from sedimentary formations, presumably underlying and adjacent top the granitic rocks, which have recently migrated into the host rocks. Alternatively, most of the chlorine but not the water, may have recently input into the system from magmatic

337

Modeling Studies of Geothermal Systems with a Free Water Surface  

DOE Green Energy (OSTI)

Numerical simulators developed for geothermal reservoir engineering applications generally only consider systems which are saturated with liquid water and/or steam. However, most geothermal fields are in hydraulic communicatino with shallow ground water aquifers having free surface (water level), so that production or injection operations will cause movement of the surface, and of the air in the pore spaces above the water level. In some geothermal fields the water level is located hundreds of meters below the surface (e.g. Olkaria, Kenya; Bjornsson, 1978), so that an extensive so that an extensive unsaturated zone is present. In other the caprock may be very leaky or nonexistent [e.g., Klamath Falls, oregon (Sammel, 1976)]; Cerro Prieto, Mexico; (Grant et al., 1984) in which case ther eis good hydraulic communication between the geothermal reservoir and the shallow unconfined aquifers. Thus, there is a need to explore the effect of shallow free-surface aquifers on reservoir behavior during production or injection operations. In a free-surface aquifer the water table moves depending upon the rate of recharge or discharge. This results in a high overall storativity; typically two orders of magnitude higher than that of compressed liquid systems, but one or two orders of magnitude lower than that for liquid-steam reservoirs. As a consequence, various data analysis methods developed for compressed liquid aquifers (such as conventional well test analysis methods) are not applicable to aquifer with a free surface.

Bodvarsson, Gudmundur S.; Pruess, K.

1983-12-15T23:59:59.000Z

338

Geology, drill holes, and geothermal energy potential of the basal Cambrian rock units of the Appalachian Basin of New York State  

DOE Green Energy (OSTI)

The published geologic and geophysical records plus data gathered from deep wells during hydrocarbon exploration were inventoried, discussed and summarized to evaluate hydro-geothermal energy potential in the western counties of New York, south of the 42/sup 0/ latitude. An assessment is provided of local geothermal energy potential based on these data. The assessed potential is a function of the geothermal gradient, the depth of porous Cambrian age sedimentary units and a variety of features thought to be related to deep fracturing and hence enhanced porosity and permeability. The completion history of a selected set of plugged and abandoned deep wells was examined to determine the feasibility and advisability of re-entering these holes for geothermal development. All wells showed extensive cement plugging and uncertain materials introduced for bridging. It was recommended that no attempt be made to re-enter these wells. The hydro-geothermal energy potential in Western New York State is largely comparable to that of other regions possessing porous/permeable units of sedimentary rock at sufficient depth to contain formation waters of useful temperatures (>140/sup 0/F). A comparison of geothermal reservoirs in New York to similar sites now under development in Canada and France has revealed that potential resources in New York State are slightly hotter, though somewhat thicker and less permeable with significantly higher proportions of dissolved constituents.

Pferd, J.W.

1981-06-01T23:59:59.000Z

339

Multiparameter fiber optic sensing system for monitoring enhanced geothermal systems  

DOE Green Energy (OSTI)

The goal of this project was to design, fabricate and test an optical fiber cable which supports multiple sensing modalities for measurements in the harsh environment of enhanced geothermal systems. To accomplish this task, optical fiber was tested at both high temperatures and strains for mechanical integrity, and in the presence of hydrogen for resistance to darkening. Both single mode (SM) and multimode (MM) commercially available optical fiber were identified and selected for the cable based on the results of these tests. The cable was designed and fabricated using a tube-within-tube construction containing two MM fibers and one SM fiber, and without supporting gel that is not suitable for high temperature environments. Commercial fiber optic sensing instruments using Raman DTS (distributed temperature sensing), Brillouin DTSS (distributed temperature and strain sensing), and Raleigh COTDR (coherent optical time domain reflectometry) were selected for field testing. A microelectromechanical systems (MEMS) pressure sensor was designed, fabricated, packaged, and calibrated for high pressure measurements at high temperatures and spliced to the cable. A fiber Bragg grating (FBG) temperature sensor was also spliced to the cable. A geothermal well was selected and its temperature and pressure were logged. The cable was then deployed in the well in two separate field tests and measurements were made on these different sensing modalities. Raman DTS measurements were found to be accurate to ???±5???°C, even with some residual hydrogen darkening. Brillouin DTSS measurements were in good agreement with the Raman results. The Rayleigh COTDR instrument was able to detect some acoustic signatures, but was generally disappointing. The FBG sensor was used to determine the effects of hydrogen darkening, but drift over time made it unreliable as a temperature or pressure sensor. The MEMS sensor was found to be highly stable and accurate to better than its 0.1% calibration.

William A. Challener

2014-12-04T23:59:59.000Z

340

Isotopic Analysis- Rock | Open Energy Information  

Open Energy Info (EERE)

Isotopic Analysis- Rock Isotopic Analysis- Rock Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Isotopic Analysis- Rock Details Activities (13) Areas (11) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: Rock Lab Analysis Parent Exploration Technique: Rock Lab Analysis Information Provided by Technique Lithology: Water rock interaction Stratigraphic/Structural: Hydrological: Thermal: Dictionary.png Isotopic Analysis- Rock: Isotopes are atoms of the same element that have different numbers of neutrons. An isotopic analysis looks at a particular isotopic element(s) in a given system, while the conditions which increase/decrease the number of neutrons are well understood and measurable.

Note: This page contains sample records for the topic "rock geothermal systems" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Vapor-pressure lowering in geothermal systems  

SciTech Connect

The water vapor-pressure lowering phenomenon in porous media was investigated for a range of temperatures by measuring vapor pressure vs. mass of water adsorbed in consolidated sandstone cores and unconsolidated silica sands. Experimental results showed that the mass of water adsorbed on the rock surface is much more than the amount of pore steam. Results also revealed that the water adsorption is caused mainly by micropores in the porous medium. Measurement of the mass of methane and ethane adsorbed on dry rocks showed that the amount of adsorption is not great in comparison with the pore gas. It was found that adsorption data for water/sandstone core studies could be normalized with respect to temperature. Although this appears not to have been reported previously, it does agree in principle with findings for solid powders with micropores. Another interesting result was that reanalysis of previous studies of capillarity in sandstones indicates that experimental data probably were influenced mostly by adsorption.

Hsieh, C.H.; Ramey, H.J. Jr.

1983-02-01T23:59:59.000Z

342

Numerical modeling of geothermal systems with applications to Krafla, Iceland and Olkaria, Kenya  

SciTech Connect

The use of numerical models for the evaluation of the generating potential of high temperature geothermal fields has increased rapidly in recent years. In the present paper a unified numerical approach to the modeling of geothermal systems is discussed and the results of recent modeling of the Krafla geothermal field in Iceland and the Olkaria, Kenya, are described. Emphasis is placed on describing the methodology using examples from the two geothermal fields.

Bodvarsson, G.S.

1987-08-01T23:59:59.000Z

343

Research on the physical properties of geothermal reservoir rock. Quarterly report, March 1978  

DOE Green Energy (OSTI)

A laboratory study of the P-wave velocity and electric resistivity was undertaken on Cenozoic volcanic rocks collected from the Columbia Plateau volcanic basin (C) and the Jemez volcanic field (NM). Electric resistivities of cylindrical samples saturated with 0.1 N NaCl solution were measured using a four electrode system and a 1.0 KHz frequency source. Seismic P-wave velocities were calculated from measured transit time of mechanical pulses generated and received by piezoelectric transducers. The electric resistivity of water saturated samples decreased as temperature increased to the boiling point of water. Above boiling point, resistivity increased rapidly as water changed to vapor. Resistivity is most sensitive to temperature changes between 35/sup 0/C to 65/sup 0/C. Resistivities of samples increased with decrease in saturation. The effect is more pronounced at lower temperatures. No dependence of seismic P-wave velocities on temperature was observed. Both resistivity and P-wave velocity depend on porosity. The increase in porosity results in a decrease in the resistivity formation factor. Assuming a relationship FF = a phi/sup -m/ (Archie's Law), where FF and phi represent the formation factor and porosity respectively, least squares indicate a variation of a between .5 and 2.0. The value of m varied between 1.2 to 1.7. Seismic velocities (v) decrease as porosity increases. Porosity appears to be linearly related to log v. Several samples show anomalous relationship between porosity and resistivity. Most of these samples also show anomalous seismic velocities. The majority of these samples have coarse grains or large pores. The effect of saturation on P-wave velocity is small and can be observed in few samples. In these samples, seismic velocities decrease with increase in saturation at high saturation (100% to 85%), and show a reverse relationship at low saturation. Between 15% and 85% saturation in velocity is constant.

Keller, G.V.; Grose, L.T.; Pickett, G.R.

1978-03-30T23:59:59.000Z

344

Experiment-Based Model for the Chemical Interactions between Geothermal  

Open Energy Info (EERE)

Experiment-Based Model for the Chemical Interactions between Geothermal Experiment-Based Model for the Chemical Interactions between Geothermal Rocks, Supercritical Carbon Dioxide and Water Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Experiment-Based Model for the Chemical Interactions between Geothermal Rocks, Supercritical Carbon Dioxide and Water Project Type / Topic 1 Recovery Act: Enhanced Geothermal Systems Component Research and Development/Analysis Project Type / Topic 2 Supercritical Carbon Dioxide / Reservoir Rock Chemical Interactions Project Description The geochemical model will be developed on a foundation of both theory and measurements of chemical and physical interactions between minerals, rocks, scCO2 and water. An experimentally validated reservoir modeling capability is critically important for the evaluation of the scCO2-EGS concept, the adoption of which could significantly enhance energy production in the USA.

345

Zuni Mountains, New Mexico as a potential dry hot rock geothermal energy Site  

DOE Green Energy (OSTI)

Many of the criteria for the successful exploitation of energy from dry hot rock are met in the Zuni Mountains, New Mexico. This area falls within a broad region of abnormally high heat flow on the Colorado Plateau. Within this region, a variety of evidence indicates that local ''hot spots'' may be present. These ''hot spots'' are prime targets for dry hot rock exploration. A site-evaluation program utilizing geological, geochemical-geochronological, and geophysical techniques is proposed to delineate the optimal sites for subsequent exploratory drilling.

Laughlin, A.W.; West, F.G.

1975-12-01T23:59:59.000Z

346

Rock Sampling | Open Energy Information  

Open Energy Info (EERE)

Rock Sampling Rock Sampling Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Rock Sampling Details Activities (13) Areas (13) Regions (1) NEPA(0) Exploration Technique Information Exploration Group: Field Techniques Exploration Sub Group: Field Sampling Parent Exploration Technique: Field Sampling Information Provided by Technique Lithology: Rock samples are used to define lithology. Field and lab analyses can be used to measure the chemical and isotopic constituents of rock samples. Stratigraphic/Structural: Provides information about the time and environment which formed a particular geologic unit. Microscopic rock textures can be used to estimate the history of stress and strain, and/or faulting. Hydrological: Isotope geochemistry can reveal fluid circulation of a geothermal system.

347

Introduction to electric energy conversion systems for geothermal energy resources  

SciTech Connect

The types of geothermal energy conversion systems in use are classified as follows: direct, dry steam; separated steam; single-flash steam; double-flash steam; multi-flash steam; brine/Freon binary cycle; and brine/isobutane binary cycle. The thermodynamics of each of these is discussed with reference to simplified flow diagrams. Typical existing power plants are identified for each type of system. (MHR)

DiPippo, R.

1978-06-01T23:59:59.000Z

348

Geothermal Heat Pump Systems: Applications and Technology Development  

Science Conference Proceedings (OSTI)

This report discusses a hybrid geothermal heat pump system, an efficient, all-electric heating and cooling option for small and large commercial buildings. In this system, the ground loop heat exchanger is sized for winter heating and supplemented by auxiliary heat rejection devices (such as fluid coolers or cooling towers) for summer operation that prevent performance-impeding heat buildup in the earth surrounding the ground loop.

2003-11-03T23:59:59.000Z

349

Baseline System Costs for 50.0 MW Enhanced Geothermal System -- A Function  

Open Energy Info (EERE)

Baseline System Costs for 50.0 MW Enhanced Geothermal System -- A Function Baseline System Costs for 50.0 MW Enhanced Geothermal System -- A Function of: Working Fluid, Technology, and Location Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Baseline System Costs for 50.0 MW Enhanced Geothermal System -- A Function of: Working Fluid, Technology, and Location Project Type / Topic 1 Recovery Act: Enhanced Geothermal Systems Component Research and Development/Analysis Project Type / Topic 2 Geothermal Analysis Project Description This effort will support the expansion of Enhanced Geothermal Systems (EGS), supporting DOE Strategic Themes of "energy security" and sub goal of "energy diversity"; reducing the Nation's dependence on foreign oil while improving our environment. A 50 MW has been chosen as a design point, so that the project may also assess how different machinery approaches will change the costing - it is a mid point in size where multiple solutions exist that will allow the team to effectively explore the options in the design space and understand the cost.

350

Geothermal Handbook  

DOE Green Energy (OSTI)

This handbook is intended to assist the physicist, chemist, engineer, and geologist engaged in discovering and developing geothermal energy resources. This first section contains a glossary of the approximately 500 most frequently occurring geological, physical, and engineering terms, chosen from the geothermal literature. Sections 2 through 8 are fact sheets that discuss such subjects as geothermal gradients, rock classification, and geological time scales. Section 9 contains conversion tables for the physical quantities of interest for energy research in general and for geothermal research in particular.

Leffel, C.S., Jr.; Eisenberg, R.A.

1977-06-01T23:59:59.000Z

351

Engineered Geothermal Systems Energy Return On Energy Investment  

SciTech Connect

Energy Return On Investment (EROI) is an important figure of merit for assessing the viability of energy alternatives. Too often comparisons of energy systems use ??efficiency? when EROI would be more appropriate. For geothermal electric power generation, EROI is determined by the electricity delivered to the consumer compared to the energy consumed to construct, operate, and decommission the facility. Critical factors in determining the EROI of Engineered Geothermal Systems (EGS) are examined in this work. These include the input energy embodied into the system. Embodied energy includes the energy contained in the materials, as well as, that consumed in each stage of manufacturing from mining the raw materials to assembling the finished system. Also critical are the system boundaries and value of the energy ?? heat is not as valuable as electrical energy. The EROI of an EGS depends upon a number of factors that are currently unknown, for example what will be typical EGS well productivity, as well as, reservoir depth, temperature, and temperature decline rate. Thus the approach developed is to consider these factors as parameters determining EROI as a function of number of wells needed. Since the energy needed to construct a geothermal well is a function of depth, results are provided as a function of well depth. Parametric determination of EGS EROI is calculated using existing information on EGS and US Department of Energy (DOE) targets and is compared to the ??minimum? EROI an energy production system should have to be an asset rather than a liability.

Mansure, A J

2012-12-10T23:59:59.000Z

352

Community Geothermal Technology Program: Bottom heating system using geothermal power for propagation. Final report, Phases 1 and 2  

DOE Green Energy (OSTI)

The objective is to develop and study a bottom-heating system in a greenhouse utilizing geothermal energy to aid germination and speed growth of palms. Source of heat was geothermal brine from HGP-A well. The project was successful; the heat made a dramatic difference with certain varieties, such as Areca catechu (betelnut) with 82% germination with heat, zero without. For other varieties, germination rates were much closer. Quality of seed is important. Tabs, figs.

Downing, J.C.

1990-01-01T23:59:59.000Z

353

Isotope hydrology of a basin and range geothermal system  

Science Conference Proceedings (OSTI)

If the geothermal resources in Dixie Valley are exploited, a complete understanding of the hydrologic system is essential in managing the geothermal system. As a reconnaissance study in an area of minimal hydrologic research, it is necessary to examine many facets of the local hydrologic cycle in Dixie Valley. To this end, this paper will discuss the isotopic composition of local precipitation, the age and origin of the hot spring waters and the type of water most important for recharge of both the thermal and nonthermal systems. This study was accomplished by using stable and radioactive environmental isotopes, and to a lesser extent, water chemistry. Dueterium and oxygen-18 were heavily relied upon in formulating conclusions, but some tritium and carbon-14 sampling were also performed.

Jacobson, R.L.; Ingraham, N.L.; Campana, M.E.

1983-08-01T23:59:59.000Z

354

Geothermal/Exploration | Open Energy Information  

Open Energy Info (EERE)

Geothermal/Exploration Geothermal/Exploration < Geothermal(Redirected from Exploration) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Land Use Leasing Exploration Well Field Power Plant Transmission Environment Water Use Print PDF Geothermal Exploration General Techniques Tree Techniques Table Regulatory Roadmap NEPA (120) Geothermal springs along Yellowstone National Park's Firehole River in the cool air of autumn. The world's most environmentally sensitive geothermal features are protected by law. Geothermal Exploration searches the earth's subsurface for geothermal resources that can be extracted for the purpose of electricity generation. A geothermal resource is as commonly a volume of hot rock and water, but in the case of EGS, is simply hot rock. Geothermal exploration programs

355

Aspects of forced convective heat transfer in geothermal systems  

DOE Green Energy (OSTI)

A knowledge of convective heat transfer is essential to understanding geothermal systems and other systems of moving groundwater. A simple, kinematic approach toward convective heat transfer is taken here. Concern is not with the cause of the groundwater motion but only with the fact that the water is moving and transferring heat. The mathematical basis of convective heat transfer is the energy equation which is a statement of the first law of thermodynamics. The general solution of this equation for a specific model of groundwater flow has to be done numerically. The numerical algorithm used here employs a finite difference approximation to the energy equation that uses central differences for the heat conduction terms and one-sided differences for the heat convection terms. Gauss--Seidel iteration is then used to solve the finite difference equation at each node of a non-uniform mesh. The Monroe and Red Hill hot springs, a small hydrothermal system in central Utah, provide an example to illustrate the application of convective heat transfer theory to a geophysical problem. Two important conclusions regarding small geothermal systems follow immediately from the results of this application. First, the most rapid temperature rise in the convecting part of a geothermal system is near the surface. Below this initially rapid temperature increase the temperature increases very slowly, and thus temperatures extrapolated from shallow boreholes can be seriously in error. Second, the temperatures and heat flows observed at Monroe and Red Hill, and probably at many other small geothermal areas, can easily result from moderate vertical groundwater velocities in faults and fracture zones in an area of normal heat flow.

Kilty, K.; Chapman, D.S.; Mase, C.

1978-07-01T23:59:59.000Z

356

Faults and gravity anomalies over the East Mesa hydrothermal-geothermal system  

DOE Green Energy (OSTI)

Detailed interpretations of gravity anomalies over geothermal systems may be extremely useful for mapping the fracture or fault systems that control the circulation of the thermal waters. This approach seems to be particularly applicable in areas like the Salton Trough where reactions between the thermal waters and the porous sediments produce authigenic-hydrothermal minerals in sufficient quantity to cause distinct gravity anomalies at the surface. A 3-D inversion of the residual Bouguer gravity anomaly over the East Mesa geothermal field was made to examine the densified volume of rock. We show that the data not only resolve a north-south and an intersecting northwest structure, but that it may be possible to distinguish between the active present-day hydrothermal system and an older and cooler part of the system. The densified region is compared spatially to self-potential, thermal and seismic results and we find a good concordance between the different geophysical data sets. Our results agree with previous studies that have indicated that the main feeder fault recharging the East Mesa reservoir dips steeply to the west.

Goldstein, N.E.; Carle, S.

1986-05-01T23:59:59.000Z

357

Thermally conductive cementitious grout for geothermal heat pump systems  

DOE Patents (OSTI)

A thermally conductive cement-sand grout for use with a geothermal heat pump system. The cement sand grout contains cement, silica sand, a superplasticizer, water and optionally bentonite. The present invention also includes a method of filling boreholes used for geothermal heat pump systems with the thermally conductive cement-sand grout. The cement-sand grout has improved thermal conductivity over neat cement and bentonite grouts, which allows shallower bore holes to be used to provide an equivalent heat transfer capacity. In addition, the cement-sand grouts of the present invention also provide improved bond strengths and decreased permeabilities. The cement-sand grouts can also contain blast furnace slag, fly ash, a thermoplastic air entraining agent, latex, a shrinkage reducing admixture, calcium oxide and combinations thereof.

Allan, Marita (Old Field, NY)

2001-01-01T23:59:59.000Z

358

Hot Dry Rock Heat Mining Geothermal Energy Development Program - Annual Report Fiscal Year 1990  

DOE Green Energy (OSTI)

This was a year of significant accomplishment in the Hot Dry Rock (HDR) Program. Most importantly, the design, construction, and installation of the surface plant for the Phase II system neared completion by the end of the year. Basic process design work has been completed, and all major components of the system except the gas/particle separator have been procured. For this component, previous design problems have been resolved, and purchase during the first half of FY91 is anticipated. Installation of the surface plant is well underway. The system will be completed and ready for operation by the end of FY91 under the current funding scenario. The operational schedule to be followed will then depend upon the program funding level. Our goal is to start long-term flow testing as soon as possible. Of equal importance, from the standpoint of the long-term viability of HDR technology, during this year, for the first time, it has been demonstrated in field testing that it should be possible to operate HDR reservoirs with water losses of 1-3%, or even less. Our experience in the deep, hot, Phase II reservoir at Fenton Hill is in sharp contrast to the significant water losses seen by Japanese and British scientists working in shallower, cooler, HDR reservoirs. Calculations and modeling based on field data have shown that water consumption declines with the log of time in a manner related to water storage in the reservoir. This work may be crucial in proving that HDR can be an economically viable means for producing energy, and that it is useful even in areas where water is in short supply. In addition, an engineering model was developed to predict and explain water consumption in HDR reservoirs under pressure, the collection and processing of seismic information was more highly automated, and the detection limits for reactive tracers were lowered to less than 1 part per billion. All of these developments will add greatly to our ability to conduct, analyze, and understand the long-term test (LTFT). Water-rights acquisition activities, site clean-up, and improvements in the 1 million gallon storage pond at Fenton Hill have assured that we will have adequate water to carry out a vigorous testing program in a safe and environmentally-sound manner. The 1 million gallon pond was recontoured, and lined with a sophisticated multi-layer plastic barrier. A large part of the work on the pond was paid for with funds from the Laboratory's Health, Safety and Environment Division. Almost all the expected achievements set forth in the FY90 Annual Operating Plan were substantially accomplished this past year, in spite of a $300,000 shortfall in funding. This funding shortfall did delay some work and result in some projects not being completed, however. They have had to go more slowly than they would like on some aspects of the installation of the surface plant for the LTFT, purchase of non-critical equipment, such as a back-up electric generator for Fenton Hill, has been delayed, and some work has not been brought to an adequate conclusion. The fracture healing work, for example, was completed but not written up. they simply did not have the funds to pay for the effort needed to fully document this work. As the program enters FY91, the completion of the surface plant at Fenton Hill is within sight. The long-awaited LTFT can then begin, and the large investment in science and technology represents by the HDR Program will begin to bear still greater dividends.

Duchane, David

1991-01-01T23:59:59.000Z

359

Geothermal Literature Review At Fenton Hill Hdr Geothermal Area (Goff &  

Open Energy Info (EERE)

Goff & Goff & Decker, 1983) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Geothermal Literature Review At Fenton Hill Hdr Geothermal Area (Goff & Decker, 1983) Exploration Activity Details Location Fenton Hill Hdr Geothermal Area Exploration Technique Geothermal Literature Review Activity Date Usefulness useful DOE-funding Unknown Notes Review and identification of 24 potential sites for EGS development across the U.S., as well as modeling of the representative geologic systems in which promising EGS sites occur. References Fraser Goff, Edward R. Decker (1983) Candidate Sites For Future Hot Dry Rock Development In The United States Retrieved from "http://en.openei.org/w/index.php?title=Geothermal_Literature_Review_At_Fenton_Hill_Hdr_Geothermal_Area_(Goff_%26_Decker,_1983)&oldid=511314"

360

Geothermal well completions: an overview of existing methods in four types of developments  

DOE Green Energy (OSTI)

Existing practices and capabilities for completing producing and injection wells for geothermal application in each of four categories of geothermal environments are discussed. Included are steam wells in hard, fractured rocks (The Geysers, California), hot water wells in sedimentary formations (Imperial Valley, California), hot, dry impermeable rocks with circulating water systems (Valles Caldera, New Mexico), and geopressured, geothermal water wells with associated hydrocarbon production on the U.S. Gulf Coast.

Snyder, R.E.

1978-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rock geothermal systems" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

High Temperature Components of Magma-Related Geothermal Systems: An Experimental and Theoretical Approach  

DOE Green Energy (OSTI)

This summarizes select components of a multi-faceted study of high temperature magmatic fluid behavior in shallow, silicic, volcano-plutonic geothermal systems. This work built on a foundation provided by DOE-supported advances made in our lab in understanding the physics and chemistry of the addition of HCI and other chlorides into the high temperature regions of geothermal systems. The emphasis of this project was to produce a model of the bolatile contributions from felsic magmatic systems to geothermal systems

Philip A. Candela; Philip M. Piccoli

2004-03-15T23:59:59.000Z

362

Geothermal district heating system feasibility analysis, Thermopolis, Wyoming  

DOE Green Energy (OSTI)

The purpose of this study is to determine the technical and economic feasibility of constructing and operating a district heating system to serve the residential, commercial, and public sectors in Thermopolis. The project geothermal resource assessment, based on reviews of existing information and data, indicated that substantial hot water resources likely exist in the Rose Dome region 10 miles northeast of Thermopolis, and with quantities capable of supporting the proposed geothermal uses. Preliminary engineering designs were developed to serve the space heating and hot water heating demands for buildings in the Thermopolis-East Thermopolis town service area. The heating district design is based on indirect geothermal heat supply and includes production wells, transmission lines, heat exchanger units, and the closed loop distribution and collection system necessary to serve the individual customers. Three options are presented for disposal of the cooled waters-reinjection, river disposal, and agricultural reuse. The preliminary engineering effort indicates the proposed system is technically feasible. The design is sized to serve 1545 residences, 190 businesses, and 24 public buildings. The peak design meets a demand of 128.2 million Btu at production rates of 6400 gpm.

Goering, S.W.; Garing, K.L.; Coury, G.; Mickley, M.C.

1982-04-26T23:59:59.000Z

363

Active metasomatism in the Cerro Prieto geothermal system, Baja California, Mexico: a telescoped low pressure/temperature metamorphic facies series  

DOE Green Energy (OSTI)

In the Cerro Prieto geothermal field, carbonate-cemented, quartzofeldspathic sediments of the Colorado River delta are being actively metasomatized into calc-silicate metamorphic rocks by reaction with alkali chloride brines between 200/sup 0/ and 370/sup 0/C, low fluid and lithostatic pressures, and low oxygen fugacities. Petrologic investigations of drill cores and cutting from over 50 wells in this field identified a prograde series of calc-silicate mineral zones which include as index minerals: wairakite, epidote, prehnite, and clinopyroxene. Associated divariant mineral assemblages are indicative of a very low pressure/temperature metamorphic facies series which encompasses the clay-carbonate, zeolite, greenschist, and amphibolite facies. This hydrothermal metamorphic facies series, which is becoming increasingly recognized in other active geothermal systems, is characterized by temperature-telescoped dehydration and decarbonation mineral equilibria. Its equivalent should now be sought in fossil hydrothermal systems.

Schiffman, P.; Elders, W.A.; Williams, A.E.; McDowell, S.D.; Bird, D.K.

1983-01-01T23:59:59.000Z

364

Geothermal: Sponsored by OSTI -- Laboratory investigation of...  

Office of Scientific and Technical Information (OSTI)

Laboratory investigation of steam adsorption in geothermal reservoir rocks Geothermal Technologies Legacy Collection HelpFAQ | Site Map | Contact Us | Admin Log On HomeBasic...

365

Seismological investigation of crack formation in hydraulic rock fracturing experiments and in natural geothermal environments. Progress report, September 1, 1977--August 31, 1978  

DOE Green Energy (OSTI)

New seismological methods were developed for determining the structure of a geothermal energy source region by the use of data from both active and passive experiments. Technical papers were published on four topics, namely: a field experiment at Kilauea Iki, source models of volcanic tremors, microearthquake source spectra, and a numerical study of elastic wave diffraction by fluid-filled cracks. In addition, papers were submitted for publication on a statistical synthesis of source mechanism of seismic events in Kilauea Iki and the observation of a temporal variation in the attenuation of earthquake coda in central California. The following subjects were worked on: (1) interpretation of seismic data from the LASL Hot Dry Rock system; (2) analyisis of volcanic tremor data from the U.S.G.S. Hawaiian seismic network; (3) frequency dependence and three-dimensional distribution of seismic attenuation in central Japan; (4) experimental study of seismic scattering by a penny-shaped crack; (5) development of a microprocessor system for the treatment of the data from digital event recorders.

Aki, K.

1978-09-01T23:59:59.000Z

366

Enthalpy transients in fractured two-phase geothermal systems  

DOE Green Energy (OSTI)

Numerical modeling techniques are used to study the changes in flowing enthalpy of fluids produced from a well completed in a fractured two-phase geothermal reservoir. Complex interactions between different fracture and porous matrix parameters control the enthalpy transients. The results show that the flowing enthalpy is most sensitive to the characteristics of the relative permeability curves, the magnitude of the matrix permeability and the effective fracture porosity. Other parameters such as the thermal conductivity and fracture spacing also significantly affect the flowing enthalpy. In spite of the complex phenomena associated with enthalpy transients in fractured two-phase systems, it is possible to infer useful information about the producing geothermal reservoirs from field data. 15 refs., 13 figs., 2 tabs.

Lippmann, M.J.; Bodvarsson, G.S.; Gaulke, S.W.

1985-03-01T23:59:59.000Z

367

Thermochronometry At Coso Geothermal Area (2003) | Open Energy Information  

Open Energy Info (EERE)

Thermochronometry At Coso Geothermal Area (2003) Thermochronometry At Coso Geothermal Area (2003) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Thermochronometry At Coso Geothermal Area (2003) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Thermochronometry Activity Date 2003 Usefulness not indicated DOE-funding Unknown Exploration Basis Determine the age of the geothermal system and the granitic host rock using the 40Ar/39Ar thermal history Notes A downhole 40Ar/39Ar thermochronology study of granitic host-rock K-feldspar is presently being undertaken at the New Mexico Geochronology Research Laboratory. The technique couples the measurement of argon loss from K-feldspar and knowledge of the diffusion parameters of transport in K-feldspar to estimate the longevity of the system at present day

368

Geothermal Heat Pump Systems in Schools: Construction, Maintenance and Operating Costs  

Science Conference Proceedings (OSTI)

Geothermal heat pumping and cooling systems are still not widely used to heat and cool buildings. They are an unknown to most architects and engineers. The electric utility industry has recognized them as being a very energy-efficient way to heat and cool buildings using electricity. The Tennessee Valley Authority (TVA) has assisted in design and installation of many geothermal systems, particularly in school buildings. With a number of geothermal heat pump systems in schools in operation in the TVA regi...

2000-12-13T23:59:59.000Z

369

An AHP approach for evaluating geothermal district energy systems[Analytical Hierarchy Process  

SciTech Connect

In the rating and design of the geothermal district energy (DE) systems the technology, cost, benefits, and environmental effects of the alternatives need to be carefully compared. This study deals with the evaluation of several alternatives of district energy systems for the city of Denizli. These alternatives vary from the existing geothermal plant to the hybrid cycle, totally integrated geothermal energy system. In the comparative evaluation of the alternative projects, Analytical Hierarchy Process (AHP) was utilized.

Eltez, A.; Kilkis, I.B.; Eltez, M.

1999-07-01T23:59:59.000Z

370

Final Report: Natural State Models of The Geysers Geothermal System, Sonoma County, California  

DOE Green Energy (OSTI)

Final project report of natural state modeling effort for The Geysers geothermal field, California. Initial models examined the liquid-dominated state of the system, based on geologic constraints and calibrated to match observed whole rock delta-O18 isotope alteration. These models demonstrated that the early system was of generally low permeability (around 10{sup -12} m{sup 2}), with good hydraulic connectivity at depth (along the intrusive contact) and an intact caprock. Later effort in the project was directed at development of a two-phase, supercritical flow simulation package (EOS1sc) to accompany the Tough2 flow simulator. Geysers models made using this package show that ''simmering'', or the transient migration of vapor bubbles through the hydrothermal system, is the dominant transition state as the system progresses to vapor-dominated. Such a system is highly variable in space and time, making the rock record more difficult to interpret, since pressure-temperature indicators likely reflect only local, short duration conditions.

T. H. Brikowski; D. L. Norton; D. D. Blackwell

2001-12-31T23:59:59.000Z

371

Geology of Injection Well 46A-19RD in the Coso Enhanced Geothermal Systems  

Open Energy Info (EERE)

of Injection Well 46A-19RD in the Coso Enhanced Geothermal Systems of Injection Well 46A-19RD in the Coso Enhanced Geothermal Systems Experiment Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: Geology of Injection Well 46A-19RD in the Coso Enhanced Geothermal Systems Experiment Details Activities (1) Areas (1) Regions (0) Abstract: The Coso Geothermal Field is a large, high temperature system located in California on the western edge of the Basin and Range province. Well 46A-19RD, located in the southwestern portion of this field is currently the focus of a DOE-funded Enhanced Geothermal Systems (EGS) project. Petrologic and petrographic investigations of the well show that quartz diorite and granodiorite are dominant lithologies. Dikes of granophyre, containing phenocrysts of plagioclase, potassium feldspar, and

372

Evaluation of the hot-dry-rock geothermal potential of an area near Mountain Home, Idaho  

DOE Green Energy (OSTI)

Evaluation of an area near Mountain Home, Idaho, was performed to assess the hot dry rock (HDR) potential of the prospect. The techniques reported include telluric and gravity profiling, passive seismic, hydrology and water chemistry surveys, and lineament analysis. Gravity and telluric surveys were unsuccessful in locating fractures buried beneath recent volcanics and sediments of the plain because density and conductivity contrasts were insufficient. Gravity modeling indicated areas where granite was not likely to be within drilling depth, and telluric profiling revealed an area in the northwest part of the prospect where higher conductivity suggested the presence of fractures or water or both, thereby making it unsuitable for HDR. Water geochemistry indicated that (hot water) reservoir temperatures do not exceed 100/sup 0/C. An area in the east central part of the prospect was delineated as most favorable for HDR development. Temperature is expected to be 200/sup 0/C at 3-km depth, and granitic rock of the Idaho Batholith should be intersected at 2- to 3-km depth.

Arney, B.H.; Goff, F.

1982-05-01T23:59:59.000Z

373

On the production behavior of enhanced geothermal systems with CO2 as working fluid  

E-Print Network (OSTI)

temperature pressure Production/Injection pattern area (Fig.injection pressure (downhole) production pressure (downhole)On the Production Behavior of Enhanced Geothermal Systems

Pruess, K.

2008-01-01T23:59:59.000Z

374

A New Gold Pan For The West- Discovering Blind Geothermal Systems...  

Open Energy Info (EERE)

blind geothermal systems in Nevada, USA and has helped to define the spatial extent of thermal anomalies at two other locations. At Teels Marsh, two shallow temperature anomalies...

375

Geothermal energy  

DOE Green Energy (OSTI)

The following subjects are discussed: areas of ''normal'' geothermal gradient, large areas of higher-than-''normal'' geothermal gradient, hot spring areas, hydrothermal systems of composite type, general problems of utilization, and domestic and world resources of geothermal energy. Almost all estimates and measurements of total heat flow published through 1962 for hot spring areas of the world are tabulated. (MHR)

White, D.E.

1965-01-01T23:59:59.000Z

376

A Geothermal District-Heating System and Alternative Energy Research Park  

Open Energy Info (EERE)

Geothermal District-Heating System and Alternative Energy Research Park Geothermal District-Heating System and Alternative Energy Research Park on the NM Tech Campus Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title A Geothermal District-Heating System and Alternative Energy Research Park on the NM Tech Campus Project Type / Topic 1 Recovery Act: Geothermal Technologies Program Project Type / Topic 2 Geothermal Energy Production from Low Temperature Resources, Coproduced Fluids from Oil and Gas Wells, and Geopressured Resources Project Type / Topic 3 Low Temperature Resources Project Description With prior support from the Department of Energy (GRED III Program), New Mexico Institute of Mining and Technology (NM Tech) has established that this resource likely has sufficient permeability (3000 Darcies) and temperatures (80-112 oC) to develop a campus-wide district heating system.

377

DOE REAL-TIME SEISMIC MONITORING AT ENHANCED GEOTHERMAL SYSTEM SITES | Open  

Open Energy Info (EERE)

REAL-TIME SEISMIC MONITORING AT ENHANCED GEOTHERMAL SYSTEM SITES REAL-TIME SEISMIC MONITORING AT ENHANCED GEOTHERMAL SYSTEM SITES Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Proceedings: DOE REAL-TIME SEISMIC MONITORING AT ENHANCED GEOTHERMAL SYSTEM SITES Details Activities (6) Areas (6) Regions (0) Abstract: Lawrence Berkeley National Laboratory (LBNL) at the direction of the United States Department of Energy (DOE) Geothermal Technologies EGS Program is installing, operating, and/or interfacing seismic arrays at multiple Enhanced Geothermal Systems (EGS) sites. The overall goal is to gather high resolution seismicity data before, during and after stimulation activities at the EGS projects. This will include both surface and borehole deployments (as necessary in available boreholes) to provide high quality

378

Active Geothermal Systems And Associated Gold Deposits In The Great Basin |  

Open Energy Info (EERE)

Geothermal Systems And Associated Gold Deposits In The Great Basin Geothermal Systems And Associated Gold Deposits In The Great Basin Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Paper: Active Geothermal Systems And Associated Gold Deposits In The Great Basin Details Activities (0) Areas (0) Regions (0) Abstract: In western North America, a number of geothermal systems derive their heat from magmas or cooling intrusions. The interior of the Great Basin however, is characterized by widespread amagmatic geothermal activity that owes its existence to high crustal heat flow and active extensional tectonics. Both the magmatically heated and extensional fluid types in the Great Basin have recently, or are currently, depositing gold. Quaternary to Pliocene-aged gold deposits with adjacent high-temperature (≤ 150°C)

379

Hot Dry Rock Geothermal Energy Development Program: Annual report, fiscal year 1985  

DOE Green Energy (OSTI)

The primary objective for the Hot Dry Rock Program at the Los Alamos National Laboratory during fiscal year 1985 was to complete the Phase 2 reservoir connection and to begin flow testing the resulting reservoir. The connection was achieved through redrilling one well and additional fracturing operations, and progress was made toward developing a detailed understanding of the fractured region through a variety of reservoir interrogation methods. Other accomplishments during the fiscal year included improvement of the high-temperature, inflatable, open-hole packer used to isolate sections of the uncased wellbore in collaboration with the Baker Corporation and the design and fabrication of a high-temperature borehole acoustic televiewer in a cooperative program with a research institute in West Germany. Progress was also made in techniques for the collection and analysis of microseismic data. Reservoir-engineering activities and geochemical studies, as well as the more routine support activities, continued in FY85. 18 refs., 15 figs.

Brown, D.W.; Franke, P.R.; Smith, M.C.; Wilson, M.G.

1987-01-01T23:59:59.000Z

380

MEMS Materials and Temperature Sensors for Down Hole Geothermal System Monitoring  

E-Print Network (OSTI)

geothermal power plants. US DOE EERE Geothermal Technologieswas made for the US DOE EERE Geothermal Technologies

Wodin-Schwartz, Sarah

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "rock geothermal systems" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Numerical simulation of reservoir compaction in liquid dominated geothermal systems  

DOE Green Energy (OSTI)

A numerical model is introduced which simulates the effects of fluid production as well as reinjection on the vertical deformation of water dominated geothermal reservoirs. This program, based on an Integrated Finite Difference technique and Terzaghi's one-dimensional consolidation model, computes the transport of heat and water through porous media, and resulting pore volume changes. Examples are presented to show the effects of reservoir heterogeneities on the compaction of these hot water systems, as well as the effects of different production-injection schemes. The use of isothermal models to simulate the deformation of non-isothermal systems was also investigated.

Lippmann, M.J.; Narasimhan, T.N.; Witherspoon, P.A.

1976-12-01T23:59:59.000Z

382

Estimating Well Costs for Enhanced Geothermal System Applications  

SciTech Connect

The objective of the work reported was to investigate the costs of drilling and completing wells and to relate those costs to the economic viability of enhanced geothermal systems (EGS). This is part of a larger parametric study of major cost components in an EGS. The possibility of improving the economics of EGS can be determined by analyzing the major cost components of the system, which include well drilling and completion. Determining what costs in developing an EGS are most sensitive will determine the areas of research to reduce those costs. The results of the well cost analysis will help determine the cost of a well for EGS development.

K. K. Bloomfield; P. T. Laney

2005-08-01T23:59:59.000Z

383

Audio-Magnetotellurics At Coso Geothermal Area (1977) | Open Energy  

Open Energy Info (EERE)

Coso Geothermal Area (1977) Coso Geothermal Area (1977) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Audio-Magnetotellurics Activity Date 1977 Usefulness not indicated DOE-funding Unknown Exploration Basis To investigate electrical properties of rocks associated with thermal phenomena of the Devil's Kitchen-Coso Hot Springs area Notes Audio-magnetotelluric geophysical surveys determined that the secondary low in the geothermal area, best defined by the 7.5-Hz AMT map and dc soundings, is caused by a shallow conductive zone (5--30 ohm m) interpreted to be hydrothermally altered Sierra Nevada basement rocks containing saline water of a hot water geothermal system. This zone of lowest apparent resistivities over the basement rocks lies within a closed contour of a

384

Geophysical logging case history of the Raft River geothermal system, Idaho  

Open Energy Info (EERE)

Geophysical logging case history of the Raft River geothermal system, Idaho Geophysical logging case history of the Raft River geothermal system, Idaho Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Report: Geophysical logging case history of the Raft River geothermal system, Idaho Details Activities (1) Areas (1) Regions (0) Abstract: Drilling to evaluate the geothermal resource in the Raft River Valley began in 1974 and resulted in the discovery of a geothermal reservoir at a depth of approximately 1523 m (500 ft). Several organizations and companies have been involved in the geophysical logging program. There is no comprehensive report on the geophysical logging, nor has there been a complete interpretation. The objectives of this study are to make an integrated interpretation of the available data and compile a case history. Emphasis has been on developing a simple interpretation

385

Geothermal Literature Review At Coso Geothermal Area (1987) | Open Energy  

Open Energy Info (EERE)

7) 7) Exploration Activity Details Location Coso Geothermal Area Exploration Technique Geothermal Literature Review Activity Date 1987 Usefulness not indicated DOE-funding Unknown Exploration Basis Compare multiple theories of the structural control of the geothermal system Notes The geothermal system appears to be associated with at least one dominant north-south-trending feature which extends several miles through the east-central portion of the Coso volcanic field. The identified producing fractures occur in zones which range from 10 - 100s of feet in extent, separated by regions of essentially unfractured rock of similar composition. Wells in the Devil's Kitchen area have encountered fluids in excess of 4500F and flow rates of 1 million lb/hr at depths less than 4000

386

Role of Fluid Pressure in the Production Behavior of EnhancedGeothermal Systems with CO2 as Working Fluid  

Science Conference Proceedings (OSTI)

Numerical simulation is used to evaluate mass flow and heatextraction rates from enhanced geothermal injection-production systemsthat are operated using either CO2 or water as heat transmission fluid.For a model system patterned after the European hot dry rock experimentat Soultz, we find significantly greater heat extraction rates for CO2 ascompared to water. The strong dependence of CO2 mobility (=density/viscosity) upon temperature and pressure may lead to unusualproduction behavior, where heat extraction rates can actually increasefor a time, even as the reservoir is subject to thermaldepletion.

Pruess, Karsten

2007-04-13T23:59:59.000Z

387

Geothermal System Overview ASHRAE Headquarters Building  

E-Print Network (OSTI)

and a corridor zone on floor 1 · Heating / cooling area for VRF ­ 18,226 sq. ft. ­ All zones on floor 1 (minus: 288.6 kBtu/hr · All zones on floor 2 and a corridor zone on floor 1 · Loads for VRF system ­ Heating,000.0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Geo HP vs VRF 2010 System Power (kWh) Geo HP VRF #12

Oak Ridge National Laboratory

388

Engineered Geothermal Systems Energy Return On Energy Investment  

DOE Green Energy (OSTI)

Critical factors in determining the EROI of Engineered Geothermal Systems (EGS) are examined in this work. These include the input energy embodied into the system. Embodied energy includes the energy contained in the materials, as well as, that consumed in each stage of manufacturing from mining the raw materials to assembling the finished system. Also critical are the system boundaries and value of the energy ?? heat is not as valuable as electrical energy. The EROI of an EGS depends upon a number of factors that are currently unknown, for example what will be typical EGS well productivity, as well as, reservoir depth, temperature, and temperature decline rate. Thus the approach developed is to consider these factors as parameters determining EROI as a function of number of wells needed. Since the energy needed to construct a geothermal well is a function of depth, results are provided as a function of well depth. Parametric determination of EGS EROI is calculated using existing information on EGS and US Department of Energy (DOE) targets and is compared to the ??minimum? EROI an energy production system should have to be an asset rather than a liability.

Mansure, A J

2012-12-10T23:59:59.000Z

389

Hot dry rock geothermal energy development program: Annual report, Fiscal year 1986  

DOE Green Energy (OSTI)

Preparation, execution, and analysis of a 30-day Initial Closed-Loop Flow Test (ICFT) of the Phase II reservoir were the primary objectives of the Hot Dry Rock Program in fiscal year 1986. The ICFT successfully tested the Phase II heat-extraction loop with the injection of 37,000 m/sup 3/ of cold water and production of 23,000 m/sup 3/ of hot water, extracting up to 10 MW/sub t/ when production reached 0.0139 m/sup 3//s at 192/degree/C. By the end of the test, water loss rate has decreased to 26% and a significant portion of the injected water had been recovered, 66% during the test and an additional 20% during subsequent venting. Geochemical, tracer, and seismic analyses suggest reservoir fracture volume was growing throughout the test. A new technique, the ''three-point'' method, was developed to determine locations and orientations of seismically active planes. Fault or joint planes are identified in what superficially appears to be an amorphous microearthquake location set. Five planes were determined when the three-point method was applied to a location data set for the massive hydraulic-fracturing experiment conducted in 1983. 23 refs., 19 figs., 3 tabs.

Dash, Z.V.; Grant, T.; Jones, G.; Murphy, H.D.; Wilson, M.G.

1989-02-01T23:59:59.000Z

390

Experimental verification of the load-following potential of a Hot Dry Rock geothermal reservoir  

Science Conference Proceedings (OSTI)

A recent 6-day flow experiment conducted at the Los Alamos National Laboratory's Fenton Hill Hot Dry Rock (HDR) test site in north-central New Mexico has verified that an HDR reservoir has the capability for a significant, and very rapid, increase in power output upon demand. The objective of this cyclic load-following experiment was to investigate the performance of the reservoir in a nominal high-backpressure (2200 psi) baseload operating condition upon which was superimposed greatly increased power production for a 4-hour period each day. In practice, this enhanced production was accomplished by dropping the production well backpressure from the preexisting level of 2200 psi down to about 500 psi to rapidly drain the fluid stored in the pressure-dilated joints surrounding the production well. During the last cycle of this six-cycle test, the mean production conditions were 146.6 gpm for 4 hours at a temperature of 189C followed by 92.4 gpm for 20 hours at a temperature of 183C. These flow and temperature values indicate a flow enhancement of 59%, and a power enhancement of 65% during the high-production period. The time required to increase the reservoir power output from the baseload to the peaking rate was about 2 minutes.

Brown, Donald

1996-01-24T23:59:59.000Z

391

Digital Mapping Of Structurally Controlled Geothermal Features With Gps  

Open Energy Info (EERE)

Digital Mapping Of Structurally Controlled Geothermal Features With Gps Digital Mapping Of Structurally Controlled Geothermal Features With Gps Units And Pocket Computers Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Conference Paper: Digital Mapping Of Structurally Controlled Geothermal Features With Gps Units And Pocket Computers Details Activities (1) Areas (1) Regions (0) Abstract: Hand-held global positioning system (GPS) units and pocket personal computers (PCs) were used to map surface geothermal features at the Bradys Hot Springs and Salt Wells geothermal systems, Churchill County, Nevada, in less time and with greater accuracy than would have been possible with conventional mapping methods. Geothermal features that were mapped include fumaroles, mud pots, warm ground, sinter, and a variety of silicified rocks. In both areas, the digital mapping was able to resolve

392

Evaluation of the second hot dry rock geothermal energy reservoir: results of Phase I, Run Segment 5  

DOE Green Energy (OSTI)

The results of a long-term (286 day) flow test of the second hot dry rock reservoir at the Fenton Hill field site are presented. This second reservoir was created by fracturing an interval of granitic rock located at a depth of 2.93 km (9620 ft) in the same wellbore pair used in the creation of the first, smaller reservoir. The new fracture system has a vertical extent of at least 320 m (1050 ft), suggesting that the combined heat-transfer area of the old and new fracture systems is much greater than that of the old system. The virgin rock temperature at the bottom of the deeper interval was 197/sup 0/C (386/sup 0/F). Downhole measurements of the water temperature at the reservoir outlet, as well as temperatures inferred from geothermometry, showed that the thermal drawdown of the reservoir was about 8/sup 0/C, and preliminary estimates indicate that the minimum effective heat-transfer area of the new reservoir is 45,000 m/sup 2/ (480,000 ft/sup 2/), which is six times larger than the first reservoir.

Zyvoloski, G.A.; Aamodt, R.L.; Aguilar, R.G.

1981-09-01T23:59:59.000Z

393

Geothermal pump down-hole energy regeneration system  

DOE Patents (OSTI)

Geothermal deep well energy extraction apparatus is provided of the general kind in which solute-bearing hot water is pumped to the earth's surface from a subterranean location by utilizing thermal energy extracted from the hot water for operating a turbine motor for driving an electrical power generator at the earth 3 s surface, the solute bearing water being returned into the earth by a reinjection well. Efficiency of operation of the total system is increased by an arrangement of coaxial conduits for greatly reducing the flow of heat from the rising brine into the rising exhaust of the down-well turbine motor.

Matthews, Hugh B. (Boylston, MA)

1982-01-01T23:59:59.000Z

394

Precipitation and scaling in dynamic geothermal systems. [Titanium loop facility  

DOE Green Energy (OSTI)

A dynamic loop facility for studying scaling in simulated geothermal brines--under conditions such as will be encountered in engineering scale heat transfer equipment is being constructed. The first phase of the program consists of two principal efforts: (1) modification of an existing 100 gpm titanium loop to provide the engineering scaling test facility and (2) operation of an approximately 1 gph once-through (experimental) system to provide design data for titanium loop modifications to provide experience with scale formation and characterization. This experience is being used in planning the scaling studies to be conducted in the dynamic loop facility. The status of the project is described.

Bohlmann, E.G.; Shor, A.J.; Berlinski, P.

1976-10-01T23:59:59.000Z

395

Blind Geothermal System Exploration in Active Volcanic Environments...  

Open Energy Info (EERE)

Buildings Clean Energy Economy Coordinated Low Emissions Assistance Network Geothermal Incentives and Policies International Clean Energy Analysis Low Emission Development...

396

Pressure analysis of the hydromechanical fracture behaviour in stimulated tight sedimentary geothermal reservoirs  

E-Print Network (OSTI)

in jointed and layered rocks in geothermal fields.of Volcanology and Geothermal Research 116, 257- 278.fracturing in a sedimentary geothermal reservoir: Results

Wessling, S.

2009-01-01T23:59:59.000Z

397

The Geysers Geothermal Field Update1990/2010  

E-Print Network (OSTI)

in The Geysers. GeothermalResourcesCouncilA planned Enhanced Geothermal System demonstrationproject. Geothermal Resources Council Transactions33,

Brophy, P.

2012-01-01T23:59:59.000Z

398

NREL: Financing Geothermal Power Projects - Planning and Timing...  

NLE Websites -- All DOE Office Websites (Extended Search)

Technology Transfer Technology Deployment Energy Systems Integration Financing Geothermal Power Projects Geothermal Technologies Financing Geothermal Power Projects Search...

399

GEOTHERMAL RESERVOIR ENGINEERING MANGEMENT PROGRAM PLAN (GREMP PLAN)  

E-Print Network (OSTI)

2 Mission of Division of Geothermal Energy . . . . .Coordination with Other Geothermal Programs . . . . . . 6the Behavior of Geothermal Systems . . . . . . . . . 1 6

Bloomster, C.H.

2010-01-01T23:59:59.000Z

400

Modeling subsidence due to geothermal fluid production  

DOE Green Energy (OSTI)

Currently, liquid dominated geothermal systems hold the maximum promise for exploiting geothermal energy in the United States. The principal characteristic of such systems is that most of the heat is transferred by flowing water, which also controls subsurface fluid pressures and stress changes. The reduction in pore pressures brought about by geothermal fluid extraction is potentially capable of causing appreciable deformation of the reservoir rocks leading to displacements at the land surface. In order to foresee the pattern and magnitude of potential ground displacements in and around producing liquid dominated geothermal fields, a numerical model has been developed. Conceptually, the simulator combines conductive and convective heat transfer in a general three dimensional heterogeneous porous medium with a one-dimensional deformation of the reservoir rocks. The capabilities of the model and its potential applicability to field cases are illustrated with examples considering the effects of temperature and pressure dependent properties, material heterogeneities and previous stress history.

Lippmann, M.J.; Narasimhan, T.N.; Witherspoon, P.A.

1977-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "rock geothermal systems" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Possible evidence for fluid-rock oxygen isotope disequilibrium in hydrothermal systems  

DOE Green Energy (OSTI)

There is ample evidence from geothermal systems that isotope temperatures estimated from the oxygen isotope fractionation between alteration phases and coexisting aquifer fluids agree closely with measured bore-hole temperatures. Similar, but limited evidence is found in epithermal vein deposits where isotopes temperature agree well with fluid inclusion homogenization temperature. Conversely, many hydrothermal systems exhibit varying degrees of fluid-rock oxygen isotope equilibration. There appears to be a crude relationship between increasing degree of equilibrium and increasing temperature and salinity. The observed variations in the degree of exchange may have resulted from local, self-sealing of the fracture network prior to equilibration. The ability for fracture to remain open or to propogate allowing continued fluid flow may be the deciding factor in the attainment of isotopic equilibration.

Cole, D.R.

1992-01-01T23:59:59.000Z

402

Possible evidence for fluid-rock oxygen isotope disequilibrium in hydrothermal systems  

DOE Green Energy (OSTI)

There is ample evidence from geothermal systems that isotope temperatures estimated from the oxygen isotope fractionation between alteration phases and coexisting aquifer fluids agree closely with measured bore-hole temperatures. Similar, but limited evidence is found in epithermal vein deposits where isotopes temperature agree well with fluid inclusion homogenization temperature. Conversely, many hydrothermal systems exhibit varying degrees of fluid-rock oxygen isotope equilibration. There appears to be a crude relationship between increasing degree of equilibrium and increasing temperature and salinity. The observed variations in the degree of exchange may have resulted from local, self-sealing of the fracture network prior to equilibration. The ability for fracture to remain open or to propogate allowing continued fluid flow may be the deciding factor in the attainment of isotopic equilibration.

Cole, D.R.

1992-04-01T23:59:59.000Z

403

Enhanced geothermal systems (EGS) using CO2 as working fluid - Anovelapproach for generating renewable energy with simultaneoussequestration of carbon  

Science Conference Proceedings (OSTI)

Responding to the need to reduce atmospheric emissions of carbon dioxide, Donald Brown (2000) proposed a novel enhanced geothermal systems (EGS) concept that would use CO{sub 2} instead of water as heat transmission fluid, and would achieve geologic sequestration of CO{sub 2} as an ancillary benefit. Following up on his suggestion, we have evaluated thermophysical properties and performed numerical simulations to explore the fluid dynamics and heat transfer issues in an engineered geothermal reservoir that would be operated with CO{sub 2}. We find that CO{sub 2} is superior to water in its ability to mine heat from hot fractured rock. CO{sub 2} also has certain advantages with respect to wellbore hydraulics, where larger compressibility and expansivity as compared to water would increase buoyancy forces and would reduce the parasitic power consumption of the fluid circulation system. While the thermal and hydraulic aspects of a CO{sub 2}-EGS system look promising, major uncertainties remain with regard to chemical interactions between fluids and rocks. An EGS system running on CO{sub 2} has sufficiently attractive features to warrant further investigation.

Pruess, Karsten

2006-06-07T23:59:59.000Z

404

Parametric Analysis of the Factors Controlling the Costs of Sedimentary Geothermal Systems - Preliminary Results (Poster)  

SciTech Connect

Parametric analysis of the factors controlling the costs of sedimentary geothermal systems was carried out using a modified version of the Geothermal Electricity Technology Evaluation Model (GETEM). The sedimentary system modeled assumed production from and injection into a single sedimentary formation.

Augustine, C.

2013-10-01T23:59:59.000Z

405

Hot rocks  

Science Conference Proceedings (OSTI)

Four kilometers down below the orange earth of Australias Cooper Basin lies some of the hottest nonvolcanic rock in the worldrock that the geothermal industry had never seriously considered using to make electricity. But next month Geodynamics, an ...

S. Upson

2009-01-01T23:59:59.000Z

406

Enhanced Geothermal Systems (EGS) R&D Program  

DOE Green Energy (OSTI)

The purpose of this workshop was to develop technical background facts necessary for planning continued research and development of Enhanced Geothermal Systems (EGS). EGS are geothermal reservoirs that require improvement of their permeability or fluid contents in order to achieve economic energy production. The initial focus of this R&D program is devising and testing means to extract additional economic energy from marginal volumes of hydrothermal reservoirs that are already producing commercial energy. By mid-1999, the evolution of the EGS R&D Program, begun in FY 1988 by the U.S. Department of Energy (DOE), reached the stage where considerable expertise had to be brought to bear on what technical goals should be pursued. The main purpose of this Workshop was to do that. The Workshop was sponsored by the Office of Geothermal Technologies of the Department of Energy. Its purpose and timing were endorsed by the EGS National Coordinating Committee, through which the EGS R&D Program receives guidance from members of the U.S. geothermal industry. Section 1.0 of this report documents the EGS R&D Program Review Session. There, managers and researchers described the goals and activities of the program. Recent experience with injection at The Geysers and analysis of downhole conditions at Dixie Valley highlighted this session. Section 2.0 contains a number of technical presentations that were invited or volunteered to illuminate important technical and economic facts and opportunities for research. The emphasis here was on fi.acture creation, detection, and analysis. Section 3.0 documents the initial general discussions of the participants. Important topics that emerged were: Specificity of defined projects, Optimizing cost effectiveness, Main technical areas to work on, Overlaps between EGS and Reservoir Technology R&D areas, Relationship of microseismic events to hydraulic fractures, and Defining criteria for prioritizing research thrusts. Sections 4.0 and 5.0 report the meat of the Workshop. Section 4.0 describes the nomination and clarification of technical thrusts, and Section 5.0 reports the results of prioritizing those thrusts via voting by the participants. Section 6.0 contains two discussions conducted after the work on research thrusts. The topics were ''Simulation'' and ''Stimulation''. A number of technical points that emerged here provide important guidance for both practical field work on EGS systems and for research.

Entingh, Daniel J.

1999-08-18T23:59:59.000Z

407

Mercury In Soils Of The Long Valley, California, Geothermal System | Open  

Open Energy Info (EERE)

In Soils Of The Long Valley, California, Geothermal System In Soils Of The Long Valley, California, Geothermal System Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Mercury In Soils Of The Long Valley, California, Geothermal System Details Activities (3) Areas (1) Regions (0) Abstract: An evaluation of the Hg distribution in soils of the Long Valley, California, geothermal area, was made. A1-horizon soil samples were collected utilizing a grid system from the resurgent dome area and the Long Valley area. In addition, samples were collected in five traverses across three fault systems and four traverses across east-west-oriented gullies to measure the importance of aspect. Additional samples were collected in an analysis of variance design to evaluate natural variability in soil composition with sampling interval distance. The primary objectives of this

408

Geothermal Systems are a Breath of Fresh Air for Illinois School District |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Geothermal Systems are a Breath of Fresh Air for Illinois School Geothermal Systems are a Breath of Fresh Air for Illinois School District Geothermal Systems are a Breath of Fresh Air for Illinois School District May 24, 2010 - 11:01am Addthis Each classroom has a geothermal unit installed. Although large, the units blend into surroundings and don’t produce excess noise. | Photo Courtesy of Sterling Public Schools Each classroom has a geothermal unit installed. Although large, the units blend into surroundings and don't produce excess noise. | Photo Courtesy of Sterling Public Schools Lindsay Gsell Superintendent Tad Everett had two priorities when deciding on a new system to replace the aging oil-based boiler heating and cooling systems for the seven schools in his district: improving learning environments and saving

409

Geothermal Systems are a Breath of Fresh Air for Illinois School District |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Geothermal Systems are a Breath of Fresh Air for Illinois School Geothermal Systems are a Breath of Fresh Air for Illinois School District Geothermal Systems are a Breath of Fresh Air for Illinois School District May 24, 2010 - 11:01am Addthis Each classroom has a geothermal unit installed. Although large, the units blend into surroundings and don’t produce excess noise. | Photo Courtesy of Sterling Public Schools Each classroom has a geothermal unit installed. Although large, the units blend into surroundings and don't produce excess noise. | Photo Courtesy of Sterling Public Schools Lindsay Gsell Superintendent Tad Everett had two priorities when deciding on a new system to replace the aging oil-based boiler heating and cooling systems for the seven schools in his district: improving learning environments and saving

410

Development of geothermal logging systems in the United States  

DOE Green Energy (OSTI)

Logging technologies developed for hydrocarbon resource evaluation have not migrated into geothermal applications even though data so obtained would strengthen reservoir characterization efforts. Two causative issues have impeded progress: (1) there is a general lack of vetted, high-temperature instrumentation, and (2) the interpretation of log data generated in a geothermal formation is in its infancy. Memory-logging tools provide a path around the first obstacle by providing quality data at a low cost. These tools feature on-board computers that process and store data, and newer systems may be programmed to make decisions. Since memory tools are completely self-contained, they are readily deployed using the slick line found on most drilling locations. They have proven to be rugged, and a minimum training program is required for operator personnel. Present tools measure properties such as temperature and pressure, and the development of noise, deviation, and fluid conductivity logs based on existing hardware is relatively easy. A more complex geochemical tool aimed at a quantitative analysis of (potassium, uranium and thorium) is in the calibration phase, and it is expandable into all nuclear measurements common in the hydrocarbon industry. A fluid sampling tool is in the design phase. All tools are designed for operation at conditions exceeding 400 C, and for deployment in the slim holes produced by mining-coring operations. Partnerships are being formed between the geothermal industry and scientific drilling programs to define and develop inversion algorithms relating raw tool data to more pertinent information. These cooperative efforts depend upon quality guidelines such as those under development within the international Ocean Drilling Program.

Lysne, P.

1994-04-01T23:59:59.000Z

411

2nd Quarterly technical progress report for geothermal system temperature-depth database  

DOE Green Energy (OSTI)

At the Southern Methodist University Geothermal Laboratory in Dallas, Texas, the Earth`s surface and internal temperature are studied. With financial support from the U.S. Department of Energy, a data base containing geothermal temperature well information for the United States is being developed. During this calendar quarter, activity with this project has continued involving several different tasks: planning and development of the geothermal system thermal-well data base and temperature-depth data, development of the specifications for the data base, and completion of an initial inventory of the geothermal areas for which data are available.

Blackwell, D.D.

1997-07-30T23:59:59.000Z

412

Structural interpretation of Coso Geothermal field, Inyo County, California  

Open Energy Info (EERE)

Coso Geothermal field, Inyo County, California Coso Geothermal field, Inyo County, California Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Structural interpretation of Coso Geothermal field, Inyo County, California Details Activities (2) Areas (1) Regions (0) Abstract: The Coso Geothermal field, located east of the Sierra Nevada at the northern edge of the high Mojave Desert in southern California, is an excellent example of a structurally controlled geothermal resource. The geothermal system appears to be associated with at least one dominant north-south-trending feature which extends several miles through the east-central portion of the Coso volcanic field. Wells drilled along this feature have encountered production from distinct fractures in crystalline basement rocks. The identified producing fractures occur in zones which

413

Property:Geothermal/OtherPrincipalInvestigator | Open Energy Information  

Open Energy Info (EERE)

OtherPrincipalInvestigator OtherPrincipalInvestigator Jump to: navigation, search Property Name Geothermal/OtherPrincipalInvestigator Property Type String Description Other Principal Investigators Subproperties This property has the following 2 subproperties: A A Geothermal District-Heating System and Alternative Energy Research Park on the NM Tech Campus Geothermal Project D Development of Chemical Model to Predict the Interactions between Supercritical CO2 and Fluid, Rocks in EGS Reservoirs Geothermal Project Pages using the property "Geothermal/OtherPrincipalInvestigator" Showing 25 pages using this property. (previous 25) (next 25) A A 3D-3C Reflection Seismic Survey and Data Integration to Identify the Seismic Response of Fractures and Permeable Zones Over a Known Geothermal Resource at Soda Lake, Churchill Co., NV Geothermal Project + John Louie, University of Nevada and Lisa Shevenell, University of Nevada +

414

Enhanced Geothermal Systems Research and Development: Models of Subsurface Chemical Processes Affecting Fluid Flow  

DOE Green Energy (OSTI)

With funding from past grants from the DOE geothermal program and other agencies, we successfully developed advanced equation of state (EOS) and simulation technologies that accurately describe the chemistry of geothermal reservoirs and energy production processes via their free energies for wide XTP ranges. Using the specific interaction equations of Pitzer, we showed that our TEQUIL chemical models can correctly simulate behavior (e.g., mineral scaling and saturation ratios, gas break out, brine mixing effects, down hole temperatures and fluid chemical composition, spent brine incompatibilities) within the compositional range (Na-K-Ca-Cl-SO4-CO3-H2O-SiO2-CO2(g)) and temperature range (T < 350C) associated with many current geothermal energy production sites that produce brines with temperatures below the critical point of water. The goal of research carried out under DOE grant DE-FG36-04GO14300 (10/1/2004-12/31/2007) was to expand the compositional range of our Pitzer-based TEQUIL fluid/rock interaction models to include the important aluminum and silica interactions (T < 350C). Aluminum is the third most abundant element in the earths crust; and, as a constituent of aluminosilicate minerals, it is found in two thirds of the minerals in the earths crust. The ability to accurately characterize effects of temperature, fluid mixing and interactions between major rock-forming minerals and hydrothermal and/or injected fluids is critical to predict important chemical behaviors affecting fluid flow, such as mineral precipitation/dissolution reactions. We successfully achieved the project goal and objectives by demonstrating the ability of our modeling technology to correctly predict the complex pH dependent solution chemistry of the Al3+ cation and its hydrolysis species: Al(OH)2+, Al(OH)2+, Al(OH)30, and Al(OH)4- as well as the solubility of common aluminum hydroxide and aluminosilicate minerals in aqueous brines containing components (Na, K, Cl) commonly dominating hydrothermal fluids. In the sodium chloride system, where experimental data for model parameterization are most plentiful, the model extends to 300C. Determining the stability fields of aluminum species that control the solubility of aluminum-containing minerals as a function of temperature and composition has been a major objective of research in hydrothermal chemistry.

Moller, Nancy; Weare J. H.

2008-05-29T23:59:59.000Z

415

NREL: Geothermal Technologies - News  

NLE Websites -- All DOE Office Websites (Extended Search)

and Technology Technology Transfer Technology Deployment Energy Systems Integration Geothermal Technologies Search More Search Options Site Map Printable Version Geothermal News...

416

Temporal changes in noble gas compositions within the Aidlinsector ofThe Geysers geothermal system  

Science Conference Proceedings (OSTI)

The use of nonreactive isotopic tracers coupled to a full thermal-hydrological reservoir simulation allows for an improved method of investigating how reservoir fluids contained within matrix and fractures contribute over time to fluids produced from geothermal systems. A combined field and modeling study has been initiated to evaluate the effects of injection, production, and fracture-matrix interaction on produced noble gas contents and isotopic ratios. Gas samples collected periodically from the Aidlin steam field at The Geysers, California, between 1997 and 2006 have been analyzed for their noble gas compositions, and reveal systematic shifts in abundance and isotopic ratios over time. Because of the low concentrations of helium dissolved in the injection waters, the injectate itself has little impact on the helium isotopic composition of the reservoir fluids over time. However, the injection process may lead to fracturing of reservoir rocks and an increase in diffusion-controlled variations in noble gas compositions, related to gases derived from fluids within the rock matrix.

Dobson, Patrick; Sonnenthal, Eric; Kennedy, Mack; van Soest,Thijs; Lewicki, Jennifer

2006-05-03T23:59:59.000Z

417

Enhanced Geothermal Systems (EGS) well construction technology evaluation report.  

DOE Green Energy (OSTI)

Electricity production from geothermal resources is currently based on the exploitation of hydrothermal reservoirs. Hydrothermal reservoirs possess three ingredients critical to present day commercial extraction of subsurface heat: high temperature, in-situ fluid and high permeability. Relative to the total subsurface heat resource available, hydrothermal resources are geographically and quantitatively limited. A 2006 DOE sponsored study led by MIT entitled 'The Future of Geothermal Energy' estimates the thermal resource underlying the United States at depths between 3 km and 10 km to be on the order of 14 million EJ. For comparison purposes, total U.S. energy consumption in 2005 was 100 EJ. The overwhelming majo