Science.gov

Sample records for reliability geothermal experience

  1. Downwell pump reliability: Geothermal experience update: Final report

    SciTech Connect

    Ellis, P.F.

    1988-01-01

    Geothermal resources with temperatures between 250/sup 0/ and 360/sup 0/F (121/sup 0/C and 182/sup 0/C) are prime candidates for binary-cycle power generation, and constitute about 80% of the power-capable resources in the United States. The successful exploitation of these resources requires reliable high-capacity downwell brine production pumps, but earlier experience showed that high-capacity, high-temperature geothermal production pumps had many problems which resulted in a mean time-to-failure (MTTF) of less than 1000 h. However, steady progress has been made since 1981, and a large body of experience has been acquired by three geothermal binary plants. This survey of high-temperature geothermal downwell pump users and manufacturers updates a prior survey (AP-3572) completed in early 1983. This survey traces the development of lineshaft pump technology from the late 1970s to the present (mid-1987), detailing the advances in design, materials selection, and operating practices. Case histories of 72 lineshaft pumps installed at three geothermal binary plants since late 1981 are documented, including some detailed cause of failure reports. In the recent past, pump lives in excess of 7000 h have become common, but a high continuing rate of premature failures resulted in a mean time-to-failure (MTTF) of about 5000 h. Based on recent advances which appear likely to eliminate most premature failures, the estimated near-term MTTF will be on the order of 8000 h. The survey found almost no development of high-temperature geothermal electric submersible pumps (ESP's) or close-coupled downwell hydraulic turbopumps, and concluded that considerable development and demonstration will be needed before these technologies are able to compete with existing high-temperature geothermal lineshaft pump technology. 36 refs., 10 figs., 25 tabs.

  2. Software Reliability Measurement Experience

    NASA Technical Reports Server (NTRS)

    Nikora, A. P.

    1993-01-01

    In this chapter, we describe a recent study of software reliability measurement methods that was conducted at the Jet Propulsion Laboratory. The first section of the chapter, sections 8.1, summarizes the study, characterizes the participating projects, describes the available data, and summarizes the tudy's results.

  3. An experiment in software reliability

    NASA Technical Reports Server (NTRS)

    Dunham, J. R.; Pierce, J. L.

    1986-01-01

    The results of a software reliability experiment conducted in a controlled laboratory setting are reported. The experiment was undertaken to gather data on software failures and is one in a series of experiments being pursued by the Fault Tolerant Systems Branch of NASA Langley Research Center to find a means of credibly performing reliability evaluations of flight control software. The experiment tests a small sample of implementations of radar tracking software having ultra-reliability requirements and uses n-version programming for error detection, and repetitive run modeling for failure and fault rate estimation. The experiment results agree with those of Nagel and Skrivan in that the program error rates suggest an approximate log-linear pattern and the individual faults occurred with significantly different error rates. Additional analysis of the experimental data raises new questions concerning the phenomenon of interacting faults. This phenomenon may provide one explanation for software reliability decay.

  4. Experiments Demonstrate Geothermal Heating Process

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2012-01-01

    When engineers design heat-pump-based geothermal heating systems for homes and other buildings, they can use coil loops buried around the perimeter of the structure to gather low-grade heat from the earth. As an alternative approach, they can drill well casings and store the summer's heat deep in the earth, then bring it back in the winter to warm…

  5. Geothermal FIT Design: International Experience and U.S. Considerations

    SciTech Connect

    Rickerson, W.; Gifford, J.; Grace, R.; Cory, K.

    2012-08-01

    Developing power plants is a risky endeavor, whether conventional or renewable generation. Feed-in tariff (FIT) policies can be designed to address some of these risks, and their design can be tailored to geothermal electric plant development. Geothermal projects face risks similar to other generation project development, including finding buyers for power, ensuring adequate transmission capacity, competing to supply electricity and/or renewable energy certificates (RECs), securing reliable revenue streams, navigating the legal issues related to project development, and reacting to changes in existing regulations or incentives. Although FITs have not been created specifically for geothermal in the United States to date, a variety of FIT design options could reduce geothermal power plant development risks and are explored. This analysis focuses on the design of FIT incentive policies for geothermal electric projects and how FITs can be used to reduce risks (excluding drilling unproductive exploratory wells).

  6. Apollo experience report: Reliability and quality assurance

    NASA Technical Reports Server (NTRS)

    Sperber, K. P.

    1973-01-01

    The reliability of the Apollo spacecraft resulted from the application of proven reliability and quality techniques and from sound management, engineering, and manufacturing practices. Continual assessment of these techniques and practices was made during the program, and, when deficiencies were detected, adjustments were made and the deficiencies were effectively corrected. The most significant practices, deficiencies, adjustments, and experiences during the Apollo Program are described in this report. These experiences can be helpful in establishing an effective base on which to structure an efficient reliability and quality assurance effort for future space-flight programs.

  7. Software reliability experiments data analysis and investigation

    NASA Technical Reports Server (NTRS)

    Walker, J. Leslie; Caglayan, Alper K.

    1991-01-01

    The objectives are to investigate the fundamental reasons which cause independently developed software programs to fail dependently, and to examine fault tolerant software structures which maximize reliability gain in the presence of such dependent failure behavior. The authors used 20 redundant programs from a software reliability experiment to analyze the software errors causing coincident failures, to compare the reliability of N-version and recovery block structures composed of these programs, and to examine the impact of diversity on software reliability using subpopulations of these programs. The results indicate that both conceptually related and unrelated errors can cause coincident failures and that recovery block structures offer more reliability gain than N-version structures if acceptance checks that fail independently from the software components are available. The authors present a theory of general program checkers that have potential application for acceptance tests.

  8. Raft River well stimulation experiments: geothermal reservoir well stimulation program

    SciTech Connect

    Not Available

    1980-08-01

    The Geothermal Reservoir Well Stimulation Program (GRWSP) performed two field experiments at the Raft River KGRA in 1979. Wells RRGP-4 and RRGP-5 were selected for the hydraulic fracture stimulation treatments. The well selection process, fracture treatment design, field execution, stimulation results, and pre- and post-job evaluations are presented.

  9. Italian Experience and Problems in Deep Geothermal Drilling

    SciTech Connect

    Cigni, U.; Del Gaudio, P.; Fabbri, F.

    1981-01-01

    Geothermal exploration at depth is being conducted in the Larderello area of Italy, in order to ascertain whether it is possible to extract geothermal fluids from the layers which underlie the reservoir now being exploited. The main operating problems are caused by the high thermality and the chemical corrosiveness of the fluids encountered; and by the practical problems involved in drilling without circulation to the surface in mainly hard but anhomogeneous fractured formations. The technology employed for deep geothermal well drilling plays an important role in this research. In deep geothermal well drilling it is essential that the equipment and the materials employed are suitable for use in areas which are characterized by high thermality and chemical corrosiveness. The results of the experiences gained in Italy concerning the materials and tools employed in deep geothermal exploration are presented. The various problems involved are described in detail and particular mention is made of drift control, fishing operations, cementation of the deep casing, control of the circulation fluid, and choice of the tubular materials.

  10. Geothermal well stimulation - program summary and the Beowawe field experiment

    SciTech Connect

    Verity, R.V.

    1983-12-01

    Republic Geothermal, Inc. and its subcontractors have planned and executed laboratory studies and eight well stimulation field experiments under the Geothermal Reservoir Well Stimulation Program (GRWSP). The program, begun in February 1979, has concentrated on extending petroleum industry stimulation technology for use by the geothermal industry. The most recent experiment was in a naturally fractured Chevron well at Beowawe and involved an acid stimulation of a damaged interval which yielded a 2.3-fold increase in injectivity. Overall results to date have shown that stimulation is viable where adequate reservoirs are penetrated by wells encountering formation damage or locally tight formations. However, wells in marginal naturally fractured reservoirs have not been saved by the types of well stimulation jobs performed thus far. A recent discovery is that many wells can possibly be made outstanding producers by widening and propping compliant natural fractures. Confirmation of this constitutes unfinished business of the GRWSP, adn offers one of the greatest potential opportunities for enhancing the economics of geothermal power production.

  11. Experiments in fault tolerant software reliability

    NASA Technical Reports Server (NTRS)

    Mcallister, David F.; Tai, K. C.; Vouk, Mladen A.

    1987-01-01

    The reliability of voting was evaluated in a fault-tolerant software system for small output spaces. The effectiveness of the back-to-back testing process was investigated. Version 3.0 of the RSDIMU-ATS, a semi-automated test bed for certification testing of RSDIMU software, was prepared and distributed. Software reliability estimation methods based on non-random sampling are being studied. The investigation of existing fault-tolerance models was continued and formulation of new models was initiated.

  12. Geothermal injection treatment: process chemistry, field experiences, and design options

    SciTech Connect

    Kindle, C.H.; Mercer, B.W.; Elmore, R.P.; Blair, S.C.; Myers, D.A.

    1984-09-01

    The successful development of geothermal reservoirs to generate electric power will require the injection disposal of approximately 700,000 gal/h (2.6 x 10/sup 6/ 1/h) of heat-depleted brine for every 50,000 kW of generating capacity. To maintain injectability, the spent brine must be compatible with the receiving formation. The factors that influence this brine/formation compatibility and tests to quantify them are discussed in this report. Some form of treatment will be necessary prior to injection for most situations; the process chemistry involved to avoid and/or accelerate the formation of precipitate particles is also discussed. The treatment processes, either avoidance or controlled precipitation approaches, are described in terms of their principles and demonstrated applications in the geothermal field and, when such experience is limited, in other industrial use. Monitoring techniques for tracking particulate growth, the effect of process parameters on corrosion and well injectability are presented. Examples of brine injection, preinjection treatment, and recovery from injectivity loss are examined and related to the aspects listed above.

  13. Tracer dilution measurements for two-phase geothermal production: Comparative testing and operating experience

    SciTech Connect

    Hirtz, P.; Lovekin, J.

    1995-12-31

    The tracer dilution technique for the measurement of steam and water mass flowrates and total enthalpy of two-phase geothermal fluids has been in routine use in the U.S.A. for almost three years. The tracer technique was first tested and adopted on a field-wide basis at the Coso geothermal field in California. Validation of the method was performed at the Roosevelt Hot Springs geothermal project in Utah and the Salton Sea and Heber geothermal projects in California by direct comparison to orifice-plate flowmeter measurements of the separated phases. Production well mass flowrates and total enthalpy are now regularly measured by this technique in the Coso, Salton Sea and Heber geothermal fields. Implementation of the tracer method is currently underway for the Tiwi and Bulalo geothermal fields in the Philippines. This paper presents the conceptual design of the measurement process, the results of field validations, and operating experience during field-wide testing in Coso.

  14. Experiments in fault tolerant software reliability

    NASA Technical Reports Server (NTRS)

    Mcallister, David F.; Vouk, Mladen A.

    1989-01-01

    Twenty functionally equivalent programs were built and tested in a multiversion software experiment. Following unit testing, all programs were subjected to an extensive system test. In the process sixty-one distinct faults were identified among the versions. Less than 12 percent of the faults exhibited varying degrees of positive correlation. The common-cause (or similar) faults spanned as many as 14 components. However, a majority of these faults were trivial, and easily detected by proper unit and/or system testing. Only two of the seven similar faults were difficult faults, and both were caused by specification ambiguities. One of these faults exhibited variable identical-and-wrong response span, i.e. response span which varied with the testing conditions and input data. Techniques that could have been used to avoid the faults are discussed. For example, it was determined that back-to-back testing of 2-tuples could have been used to eliminate about 90 percent of the faults. In addition, four of the seven similar faults could have been detected by using back-to-back testing of 5-tuples. It is believed that most, if not all, similar faults could have been avoided had the specifications been written using more formal notation, the unit testing phase was subject to more stringent standards and controls, and better tools for measuring the quality and adequacy of the test data (e.g. coverage) were used.

  15. Use of slim holes for geothermal exploration and reservoir assessment: A preliminary report on Japanese experience

    SciTech Connect

    Garg, S.K.; Combs, J.

    1993-06-01

    The publicly available Japanese data on the use of slim holes in geothermal exploration and reservoir assessment are reviewed in this report. Slim holes have been used for (1) obtaining core for geological studies, (2) delineating the stratigraphic structure, (3) characterizing reservoir fluid state (pressure, temperature, etc.), and (4) defining the permeability structure for reservoir assessment. Examples of these uses of slim hole data are presented from the Hohi Geothermal Area and the Sumikawa Geothermal Field. Discharge data from slim holes and production wells from the Oguni Geothermal Field indicate that it may be possible to infer the discharge rate of production wells based on slim hole measurements. The Japanese experience suggests that slim holes can provide useful data for cost-effective geothermal reservoir assessment. Therefore, plans for a full scale evaluation of Japanese slim hole data are outlined.

  16. Community Geothermal Technology Program: Cloth dyeing by geothermal steam. An experiment in technology transfer from Japan to Hawaii, Final report

    SciTech Connect

    Furumoto, A.S.

    1987-12-31

    This was an experiment to test whether cloth dyeing using geothermal steam (already proven in Japan) would be feasible in Hawaii. Results: Using a fabricated steam vat, cotton, silk, and synthetic can be dyed; the resulting material received high grades for steadfastness and permanency under dye testing. Techniques that were successful in Matsukawa, were replicated in Puna. However, attempts to embed leaf patterns on cloth using natural leaves and to extract natural dyes from Hawaiian plants were unsuccessful; the color of natural dyes deteriorated in hours. But chemical dyes gave brilliant hues or shades, in contrast to those in Japan where the steam there gave subdued tones. It is concluded that geothermal dyeing can be a viable cottage industry in Puna, Hawaii.

  17. Qualification Users' Perceptions and Experiences of Assessment Reliability

    ERIC Educational Resources Information Center

    Chamberlain, Suzanne

    2013-01-01

    This paper presents the findings of a study designed to explore qualification users' perceptions and experiences of reliability in the context of national assessment outcomes in England. The study consisted of 17 focus groups conducted across six sectors of qualification users: students, teachers, trainee teachers, job-seekers, employers and…

  18. MEMS Reliability: Infrastructure, Test Structures, Experiments, and Failure Modes

    SciTech Connect

    TANNER,DANELLE M.; SMITH,NORMAN F.; IRWIN,LLOYD W.; EATON,WILLIAM P.; HELGESEN,KAREN SUE; CLEMENT,J. JOSEPH; MILLER,WILLIAM M.; MILLER,SAMUEL L.; DUGGER,MICHAEL T.; WALRAVEN,JEREMY A.; PETERSON,KENNETH A.

    2000-01-01

    The burgeoning new technology of Micro-Electro-Mechanical Systems (MEMS) shows great promise in the weapons arena. We can now conceive of micro-gyros, micro-surety systems, and micro-navigators that are extremely small and inexpensive. Do we want to use this new technology in critical applications such as nuclear weapons? This question drove us to understand the reliability and failure mechanisms of silicon surface-micromachined MEMS. Development of a testing infrastructure was a crucial step to perform reliability experiments on MEMS devices and will be reported here. In addition, reliability test structures have been designed and characterized. Many experiments were performed to investigate failure modes and specifically those in different environments (humidity, temperature, shock, vibration, and storage). A predictive reliability model for wear of rubbing surfaces in microengines was developed. The root causes of failure for operating and non-operating MEMS are discussed. The major failure mechanism for operating MEMS was wear of the polysilicon rubbing surfaces. Reliability design rules for future MEMS devices are established.

  19. An Approach to Studying the Reliability of Microgravity Experiments

    NASA Technical Reports Server (NTRS)

    Thaggard, Michael; Morilak, Daniel P.

    1994-01-01

    The identification of key factors that influence the nonsuccess of experiments conducted under microgravity conditions will aid in the planning, design, and implementation of future space shuttle experiments, as well as other microgravity experiments (i.e., experiments conducted on the space station). Similarly, knowledge of the experiments' reliability will assist in forecasting the success of forthcoming experiments. Since a relatively large number of space shuttle experiments have been conducted to date, a substantial pool of data exists for assessing the possible causes or factors which influence experiment nonsuccesses. This report details the task being undertaken at NASA Lewis Research Center (LeRC) to measure the space shuttle experiments' nonsuccess trends and identify causes that significantly affect their performance. It addresses the activities associated with correlating experiment macro-factors with experiment nonsuccesses. The development and implementation of a microgravity database to be used for tracking and correlating experiment nonsuccess factors, as well as the criteria for measuring experiment success and nonsuccess, are also discussed.

  20. Experiments in software reliability - Life-critical applications

    NASA Technical Reports Server (NTRS)

    Dunham, J. R.

    1986-01-01

    The paper discusses four reliability data gathering experiments which were conducted using a small sample of programs for two problems having ultrareliability requirements, n-version programming for fault detection, and repetitive run modeling for failure and fault rate estimation. The experimental results agree with those of Nagel and Skrivan in that the program error rates suggest an approximate log-linear pattern and the individual faults occurred with significantly different error rates. Additional analysis of the experimental data raises new questions concerning the phenomenon of interacting faults. This phenomenon may provide one explanation for software reliability decay. The fourth experiment underscored the difficulty in distinguishing between observations of deficiencies in the design of the algorithm and observations of software faults for real-time process control software. These experiments are a part of a program of serial experiments being pursued by the System Validation Methods of NASA-Langley Research Center to find a means of credibly performing reliability evaluations of flight control software.

  1. An Experiment in Determining Software Reliability Model Applicability

    NASA Technical Reports Server (NTRS)

    Nikora, Allen P.

    1995-01-01

    There have been few reports on the behavior of software reliability models under controlled conditions. That is to say, most of the reported experience with the models is during the testing phase of actual projects, during which researchers have little or no control over the data with which they work. Give that failure data for actual projects can be noisy, distorted, and uncertain, reported procedures for determining model applicability may be incomplete.

  2. Session 10: The Cerro Prieto Geothermal Field, Mexico: The Experiences Gained from Its Exploration and Development

    SciTech Connect

    Lippman, M.J.; Goldstein, N.E.; Halfman, S.E.; Witherspoon, P.A.

    1983-12-01

    The Cerro Prieto case study demonstrated the value of a multidisciplinary effort for exploring and developing a geothermal field. There was no problem in recognizing the geothermal potential of the Cerro Prieto area because of the many obvious surface manifestations. However, the delineation of the geothermal reservoir at depth was not so straightforward. Wells drilled near the abundant surface manifestations only produced fluids of relatively low enthalpy. Later it was determined that these zones of high heat loss corresponded to discharge areas where faults and fractures allowed thermal fluids to leak to the surface, and not to the main geothermal reservoir. The early gravity and seismic refraction surveys provided important information on the general structure of the area. Unaware of the existence of a higher density zone of hydrothermally altered sediments capping the geothermal reservoir, CFE interpreted a basement horst in the western part of the field and hypothesized that the bounding faults were controlling the upward flow of thermal fluids. Attempting to penetrate the sedimentary column to reach the ''basement horst'', CFE discovered the {alpha} geothermal reservoir (in well M-5). The continuation of the geothermal aquifer (actually the {beta} reservoir) east of the original well field was later confirmed by a deep exploration well (M-53). The experience of Cerro Prieto showed the importance of chemical ratios, and geothermometers in general, in establishing the subsurface temperatures and fluid flow patterns. Fluid chemical and isotopic compositions have also been helpful to determine the origin of the fluids, fluid-production mechanisms and production induced effects on the reservoir.

  3. Geothermal non-power application: The PNOC experience

    SciTech Connect

    Chua, S.E.; Abito, G.F.; Berbano, M.C.

    1996-12-31

    A 1 MWth multi-crop dehydration plant using waste geothermal energy is being operated by the Philippine National Oil Company-Energy Development Corporation (PNOC-EDC) at one of the reinjection pads at the Southern Negros Geothermal Project (SNGP). The facility is composed of two heat exchange systems, seven modular dryers of three different designs, a processing and storage area, a laboratory for quality control tests and an office for general administration and other services. Products from the plant include copra (dried coconut meat), dried fruits, fish and squid, and other agricultural products. Pilot demonstration runs showed the techno-economic: viability of the drying plant. Calculated IRR for production of copra and fruits is 19.3 %, giving a payback period on capital investment of 4.2 years. Sustainability of the operation of the plant requires detailed logistical, production, and marketing plans for the assumed production mix. The facility, which is from a grant from the United Nations Development Programme, is proposed to be {open_quotes}turned over{close_quotes} to a PNOC-formed consortium of farmers cooperatives and associations for its continuous operation and management as a profitable business venture for the community.

  4. In situ experiments of geothermal well stimulation using gas fracturing technology

    SciTech Connect

    Chu, T.Y.; Warpinski, N.; Jacobson, R.D.

    1988-07-01

    The results of an experimental study of gas fracturing technology for geothermal well stimulation demonstrated that multiple fractures could be created to link water-filled boreholes with existing fractures. The resulting fracture network and fracture interconnections were characterized by mineback as well as flow tests. Commercial oil field fracturing tools were used successfully in these experiments. Simple scaling laws for gas fracturing and a brief discussion of the application of this technique to actual geothermal well stimulation are presented. 10 refs., 42 figs., 4 tabs.

  5. Automatically generated acceptance test: A software reliability experiment

    NASA Technical Reports Server (NTRS)

    Protzel, Peter W.

    1988-01-01

    This study presents results of a software reliability experiment investigating the feasibility of a new error detection method. The method can be used as an acceptance test and is solely based on empirical data about the behavior of internal states of a program. The experimental design uses the existing environment of a multi-version experiment previously conducted at the NASA Langley Research Center, in which the launch interceptor problem is used as a model. This allows the controlled experimental investigation of versions with well-known single and multiple faults, and the availability of an oracle permits the determination of the error detection performance of the test. Fault interaction phenomena are observed that have an amplifying effect on the number of error occurrences. Preliminary results indicate that all faults examined so far are detected by the acceptance test. This shows promise for further investigations, and for the employment of this test method on other applications.

  6. Session 18: Geothermal Well Stimulation - Program Summary and the Beowawe Field Experiment

    SciTech Connect

    Verity, R.V.

    1983-12-01

    Republic Geothermal, Inc. and its subcontractors have planned and executed laboratory studies and eight well stimulation field experiments under the Geothermal Reservoir Well Stimulation Program (GRWSP). The program, begun in February 1979, has concentrated on extending petroleum industry stimulation technology for use by the geothermal industry. The most recent experiment was in a naturally fractured Chevron well at Beowawe and involved an acid stimulation of a damaged interval which yielded a 2.3-fold increase in injectivity. Overall results to date have shown that stimulation is viable where adequate reservoirs are penetrated by wells encountering formation damage or locally tight formations. However, wells in marginal naturally fractured reservoirs have not been saved by the types of well stimulation jobs performed thus far. A recent discovery is that many wells can possibly be made outstanding producers by widening and propping compliant natural fractures. Confirmation of this constitutes unfinished business of the GRWSP, and offers one of the greatest potential opportunities for enhancing the economics of geothermal power production.

  7. Hydrologic ensemble prediction experiment focuses on reliable forecasts

    NASA Astrophysics Data System (ADS)

    Franz, Kristie; Ajami, Newsha; Schaake, John; Buizza, Roberto

    The Hydrologic Ensemble Prediction Experiment (HEPEX), an effort involving meteorological and hydrological scientists from research, operational, and user communities around the globe, is building a research project focused on advancing probabilistic hydrologic forecasting.HEPEX was launched in March 2004 at a meeting hosted by the European Centre for Medium-Range Weather Forecasts (ECMWF), in Reading, United Kingdom http://www.ecmwf.int/newsevents/meetings/workshops/2004/HEPEX/). The goal of HEPEX is “to bring the international hydrological and meteorological communities together to demonstrate how to produce reliable hydrological ensemble forecasts that can be used with confidence by the emergency management and water resources sectors to make decisions that have important consequences for the economy, public health, and safety.”

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

    SciTech Connect

    Stephen L. Karner, Ph.D

    2006-06-01

    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.

  9. Recirculation System for Geothermal Energy Recovery in Sedimentary Formations: Laboratory Experiments and Numerical Simulations

    NASA Astrophysics Data System (ADS)

    Elkhoury, J. E.; Detwiler, R. L.; Serajian, V.; Bruno, M. S.

    2012-12-01

    Geothermal energy resources are more widespread than previously thought and have the potential for providing a significant amount of sustainable clean energy worldwide. In particular, hot permeable sedimentary formations provide many advantages over traditional geothermal recovery and enhanced geothermal systems in low permeability crystalline formations. These include: (1) eliminating the need for hydraulic fracturing, (2) significant reduction in risk for induced seismicity, (3) reducing the need for surface wastewater disposal, (4) contributing to decreases in greenhouse gases, and (5) potential use for CO2 sequestration. Advances in horizontal drilling, completion, and production technology from the oil and gas industry can now be applied to unlock these geothermal resources. Here, we present experimental results from a laboratory scale circulation system and numerical simulations aimed at quantifying the heat transfer capacity of sedimentary rocks. Our experiments consist of fluid flow through a saturated and pressurized sedimentary disc of 23-cm diameter and 3.8-cm thickness heated along its circumference at a constant temperature. Injection and production ports are 7.6-cm apart in the center of the disc. We used DI de-aired water and mineral oil as working fluids and explored temperatures from 20 to 150 oC and flow rates from 2 to 30 ml/min. We performed experiments on sandstone samples (Castlegate and Kirby) with different porosity, permeability and thermal conductivity to evaluate the effect of hydraulic and thermal properties on the heat transfer capacity of sediments. The producing fluid temperature followed an exponential form with time scale transients between 15 and 45 min. Steady state outflow temperatures varied between 60% and 95% of the set boundary temperature, higher percentages were observed for lower temperatures and flow rates. We used the flow and heat transport simulator TOUGH2 to develop a numerical model of our laboratory setting. Given

  10. Measurement and Its Reliability: An Introductory Laboratory Experiment

    ERIC Educational Resources Information Center

    Poultney, Sherman K.

    1971-01-01

    Describes a laboratory activity about measurement and its reliability for general education students. The measurement focuses on automobile speeds and allows for estimates of errors, experimental design, and relativity in addition to kinematical concepts. (DS)

  11. Experiences with Two Reliability Data Collection Efforts (Presentation)

    SciTech Connect

    Sheng, S.; Lantz, E.

    2013-08-01

    This presentation, given by NREL at the Wind Reliability Experts Meeting in Albuquerque, New Mexico, outlines the causes of wind plant operational expenditures and gearbox failures and describes NREL's efforts to create a gearbox failure database.

  12. High energy gas fracture experiments in liquid-filled boreholes: potential geothermal application

    SciTech Connect

    Cuderman, J.F.; Chu, T.Y.; Jung, J.; Jacobson, R.D.

    1986-07-01

    High Energy Gas Fracturing is a tailored pulse fracturing technique which uses propellants to obtain controlled fracture initiation and extension. Borehole pressurization rates can be tailored, by suitable choice of propellants, to produce four or eight fractures radiating from the wellbore. High Energy Gas Fracture (HEGF) research is conducted at DOE's Nevada Test Site (NTS) in a tunnel complex where experiments can be done under realistic in situ stress conditions (1400 psi (9.7 MPa) overburden stress). Pressure measurements are made in the test borehole during all fracturing experiments. Experiments are mined back to provide direct observation of fracturing obtained. The initial objective of HEGF research was to develop multiple fracturing technology for application in gas well stimulation. HEGF research at NTS and in Devonian shale demonstration tests has resulted in a completed technology for multiple fracturing in uncased, liquid-free wellbores. Current resarch is directed toward extending the technique to liquid-filled boreholes for application in geothermal in addition to gas and oil wells. For liquid-free boreholes, multiple fracturing is specified in terms of pressure risetime required for a given borehole diameter. Propellants are mixed to achieve the desired risetime using a semiempirical mixing equation. The same techniques were successfully applied to fracturing in liquid-filled wellbores. However, the addition of liquid in the borehole results in a significantly more complicated fracturing behavior. Hydrodynamic effects are significant. Multiple fractures are initiated but only some propagated. Multiple- and hydraulic-type fracturing and wellbore crushing have been observed in the same experiment. The potential of using HEGB for geothermal well stimulation has been demonstrated through the present experiments. 18 refs., 40 figs., 4 tabs.

  13. Enhancing Experiment Central Service Reliability: from delivery to security and virtualization

    NASA Astrophysics Data System (ADS)

    Donno, F.; Baranov, S.; Buzykaev, S.; Saiz Santos, M. D.

    2011-12-01

    The four LHC experiments rely on experiment specific services running on machines mainly located at CERN. Some of these services have been rated by the experiments as very critical: any loss or degradation of performance has a major impact on the experiment's production and analysis activities. It is therefore important to provide a reliable and robust operational environment. In this work we describe the strategy based on service deployment, security and virtualization adopted to enhance the reliability of ATLAS and CMS central services.

  14. A cost assessment of reliability requirements for shuttle-recoverable experiments

    NASA Technical Reports Server (NTRS)

    Campbell, J. W.

    1975-01-01

    The relaunching of unsuccessful experiments or satellites will become a real option with the advent of the space shuttle. An examination was made of the cost effectiveness of relaxing reliability requirements for experiment hardware by allowing more than one flight of an experiment in the event of its failure. Any desired overall reliability or probability of mission success can be acquired by launching an experiment with less reliability two or more times if necessary. Although this procedure leads to uncertainty in total cost projections, because the number of flights is not known in advance, a considerable cost reduction can sometimes be achieved. In cases where reflight costs are low relative to the experiment's cost, three flights with overall reliability 0.9 can be made for less than half the cost of one flight with a reliability of 0.9. An example typical of shuttle payload cost projections is cited where three low reliability flights would cost less than $50 million and a single high reliability flight would cost over $100 million. The ratio of reflight cost to experiment cost is varied and its effect on the range in total cost is observed. An optimum design reliability selection criterion to minimize expected cost is proposed, and a simple graphical method of determining this reliability is demonstrated.

  15. Addendum to material selection guidelines for geothermal energy-utilization systems. Part I. Extension of the field experience data base. Part II. Proceedings of the geothermal engineering and materials (GEM) program conference (San Diego, CA, 6-8 October 1982)

    SciTech Connect

    Smith, C.S.; Ellis, P.F. II

    1983-05-01

    The extension of the field experience data base includes the following: key corrosive species, updated field experiences, corrosion of secondary loop components or geothermal binary power plants, and suitability of conventional water-source heat pump evaporator materials for geothermal heat pump service. Twenty-four conference papers are included. Three were abstracted previously for EDB. Separate abstracts were prepared for twenty-one. (MHR)

  16. Software reliability: Additional investigations into modeling with replicated experiments

    NASA Technical Reports Server (NTRS)

    Nagel, P. M.; Schotz, F. M.; Skirvan, J. A.

    1984-01-01

    The effects of programmer experience level, different program usage distributions, and programming languages are explored. All these factors affect performance, and some tentative relational hypotheses are presented. An analytic framework for replicated and non-replicated (traditional) software experiments is presented. A method of obtaining an upper bound on the error rate of the next error is proposed. The method was validated empirically by comparing forecasts with actual data. In all 14 cases the bound exceeded the observed parameter, albeit somewhat conservatively. Two other forecasting methods are proposed and compared to observed results. Although demonstrated relative to this framework that stages are neither independent nor exponentially distributed, empirical estimates show that the exponential assumption is nearly valid for all but the extreme tails of the distribution. Except for the dependence in the stage probabilities, Cox's model approximates to a degree what is being observed.

  17. Using Information from Operating Experience to Inform Human Reliability Analysis

    SciTech Connect

    Bruce P. Hallbert; David I. Gertman; Julie Marble; Erasmia Lois; Nathan Siu

    2004-06-01

    This paper reports on efforts being sponsored by the U.S. NRC and performed by INEEL to develop a technical basis and perform work to extract information from sources for use in HRA. The objectives of this work are to: 1) develop a method for conducting risk-informed event analysis of human performance information that stems from operating experience at nuclear power plants and for compiling and documenting the results in a structured manner; 2) provide information from these analyses for use in risk-informed and performance-based regulatory activities; 3) create methods for information extraction and a repository for this information that, likewise, support HRA methods and their applications.

  18. Interrater reliability of quantitative ultrasound using force feedback among examiners with varied levels of experience

    PubMed Central

    Ismail, Catheeja; Monfaredi, Reza; Hernandez, Haniel J.; Pennington, Donte; Woletz, Paula; McIntosh, Valerie; Adams, Bernadette; Blackman, Marc R.

    2016-01-01

    Background. Quantitative ultrasound measures are influenced by multiple external factors including examiner scanning force. Force feedback may foster the acquisition of reliable morphometry measures under a variety of scanning conditions. The purpose of this study was to determine the reliability of force-feedback image acquisition and morphometry over a range of examiner-generated forces using a muscle tissue-mimicking ultrasound phantom. Methods. Sixty material thickness measures were acquired from a muscle tissue mimicking phantom using B-mode ultrasound scanning by six examiners with varied experience levels (i.e., experienced, intermediate, and novice). Estimates of interrater reliability and measurement error with force feedback scanning were determined for the examiners. In addition, criterion-based reliability was determined using material deformation values across a range of examiner scanning forces (1–10 Newtons) via automated and manually acquired image capture methods using force feedback. Results. All examiners demonstrated acceptable interrater reliability (intraclass correlation coefficient, ICC = .98, p < .001) for material thickness measures obtained using force feedback. Individual examiners exhibited acceptable reliability with the criterion-based reference measures (ICC > .90, p < .001), independent of their level of experience. The measurement error among all examiners was 1.5%–2.9% across all applied stress conditions. Conclusion. Manual image capture with force feedback may aid the reliability of morphometry measures across a range of examiner scanning forces, and allow for consistent performance among examiners with differing levels of experience. PMID:27366647

  19. Lost circulation in geothermal wells: survey and evaluation of industry experience

    SciTech Connect

    Goodman, M.A.

    1981-07-01

    Lost circulation during drilling and completion of geothermal wells can be a severe problem, particularly in naturally fractured and/or vugular formations. Geothermal and petroleum operators, drilling service companies, and independent consultants were interviewed to assess the lost circulation problem in geothermal wells and to determine general practices for preventing lost circulation. This report documents the results and conclusions from the interviews and presents recommendations for needed research. In addition, a survey was also made of the lost circulation literature, of currently available lost circulation materials, and of existing lost circulation test equipment.

  20. Stanford Geothermal Program

    SciTech Connect

    R. Horn

    1999-06-30

    Reliable measurement of steam-water relative permeability functions is of great importance for geothermal reservoir performance simulation. Despite their importance, these functions are poorly known due to the lack of fundamental understanding of steam-water flows, and the difficulty of making direct measurements. The Stanford Geothermal Program has used an X-ray CT (Computer Tomography) scanner to obtain accurate saturation profiles by direct measurement. During the last five years, the authors have carried out experiments with nitrogen-water flow and with steam-water flow, and examined the effects of heat transfer and phase change by comparing these sets of results. In porous rocks, it was found that the steam-water relative permeabilities follow Corey type relationships similar to those in nitrogen-water flow, but that the irreducible gas phase saturation is smaller for steam than for nitrogen. The irreducible saturations represent substantial fractions of the recoverable energy in place yet are hard to determine in the field. Understanding the typical magnitude of irreducible saturations will lead to a much clearer forecast of geothermal field performance. In fracture flow, indirect measurements suggested that the relative permeabilities follow a linear (or ''X-curve'') behavior - but there is still considerable uncertainty in the knowledge of this behavior.

  1. Geothermal Energy Program overview

    SciTech Connect

    Not Available

    1991-12-01

    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.

  2. Geothermal energy program overview

    NASA Astrophysics Data System (ADS)

    1991-12-01

    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 within 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 percent of the total U.S. 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 U.S. 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.

  3. Geothermal Gases--Community Experiences, Perceptions, and Exposures in Northern California.

    PubMed

    Chiu, Cindy H; Lozier, Matthew J; Bayleyegn, Tesfaye; Tait, Karen; Barreau, Tracy; Copan, Lori; Roisman, Rachel; Jackson, Rebecca; Smorodinsky, Svetlana; Kreutzer, Richard A; Yip, Fuyuen; Wolkin, Amy

    2015-12-01

    Lake County, California, is in a high geothermal-activity area. Over the past 30 years, the city of Clearlake has reported health effects and building evacuations related to geothermal venting. Previous investigations in Clearlake revealed hydrogen sulfide at levels known to cause health effects and methane at levels that can cause explosion risks. The authors conducted an investigation in multiple cities and towns in Lake County to understand better the risk of geothermal venting to the community. They conducted household surveys and outdoor air sampling of hydrogen sulfide and methane and found community members were aware of geothermal venting and some expressed concerns. The authors did not, however, find hydrogen sulfide above the California Environmental Protection Agency air quality standard of 30 parts per billion over one hour or methane above explosive thresholds. The authors recommend improving risk communication, continuing to monitor geothermal gas effects on the community, and using community reports and complaints to monitor and document geothermal venting incidents. PMID:26738314

  4. Traveling-wave tube reliability estimates, life tests, and space flight experience

    NASA Technical Reports Server (NTRS)

    Lalli, V. R.; Speck, C. E.

    1977-01-01

    Infant mortality, useful life, and wearout phase of twt life are considered. The performance of existing developmental tubes, flight experience, and sequential hardware testing are evaluated. The reliability history of twt's in space applications is documented by considering: (1) the generic parts of the tube in light of the manner in which their design and operation affect the ultimate reliability of the device, (2) the flight experience of medium power tubes, and (3) the available life test data for existing space-qualified twt's in addition to those of high power devices.

  5. Adsorption and transformation of ammonium ion in a loose-pore geothermal reservoir: Batch and column experiments

    NASA Astrophysics Data System (ADS)

    Zhao, Li; Li, Yanli; Wang, Shidong; Wang, Xinyi; Meng, Hongqi; Luo, Shaohe

    2016-09-01

    Adsorption kinetics and transformation process of ammonium ion (NH4+) were investigated to advance the understanding of N cycle in a low-temperature loose-pore geothermal reservoir. Firstly, batch experiments were performed in order to determine the sorption capacity and the kinetic mechanism of NH4+ onto a loose-pore geothermal reservoir matrix. Then column experiments were carried out at temperatures from 20 °C to 60 °C in order to determine the transport parameters and transformation mechanism of NH4+ in the studied matrix. The results showed that the adsorption process of NH4+ onto the porous media well followed the pseudo-second-order model. No obvious variation of hydrodynamic dispersion coefficient (D) and retardation factor (R) was observed at different transport distances at a Darcy's flux of 2.27 cm/h, at which nitrification could be neglected. The simulated D obtained by the CDE model in CXTFIT2.1 increased with temperature while R decreased with temperature, indicating that the adsorption capacity of NH4+ onto the matrix decreased with the increasing of temperature. When the Darcy's flux was decreased to 0.014 cm/h, only a little part of NH4+ could be transformed to nitrate, suggesting that low density of nitrifiers existed in the simulated loose-pore geothermal reservoir. Although nitrification rate increased with temperature in the range of 20 °C to 60 °C, it was extremely low and no accumulation of nitrite was observed under the simulated low-temperature geothermal conditions without addition of biomass and oxygen.

  6. Adsorption and transformation of ammonium ion in a loose-pore geothermal reservoir: Batch and column experiments.

    PubMed

    Zhao, Li; Li, Yanli; Wang, Shidong; Wang, Xinyi; Meng, Hongqi; Luo, Shaohe

    2016-09-01

    Adsorption kinetics and transformation process of ammonium ion (NH4(+)) were investigated to advance the understanding of N cycle in a low-temperature loose-pore geothermal reservoir. Firstly, batch experiments were performed in order to determine the sorption capacity and the kinetic mechanism of NH4(+) onto a loose-pore geothermal reservoir matrix. Then column experiments were carried out at temperatures from 20°C to 60°C in order to determine the transport parameters and transformation mechanism of NH4(+) in the studied matrix. The results showed that the adsorption process of NH4(+) onto the porous media well followed the pseudo-second-order model. No obvious variation of hydrodynamic dispersion coefficient (D) and retardation factor (R) was observed at different transport distances at a Darcy's flux of 2.27cm/h, at which nitrification could be neglected. The simulated D obtained by the CDE model in CXTFIT2.1 increased with temperature while R decreased with temperature, indicating that the adsorption capacity of NH4(+) onto the matrix decreased with the increasing of temperature. When the Darcy's flux was decreased to 0.014cm/h, only a little part of NH4(+) could be transformed to nitrate, suggesting that low density of nitrifiers existed in the simulated loose-pore geothermal reservoir. Although nitrification rate increased with temperature in the range of 20°C to 60°C, it was extremely low and no accumulation of nitrite was observed under the simulated low-temperature geothermal conditions without addition of biomass and oxygen. PMID:27356192

  7. Using High Pressure Thermal Vessel For Mineral Solubility Experiments in Geothermal System

    NASA Astrophysics Data System (ADS)

    Liu, H. L.; Huang, Y. H.; Chen, H. F.; Song, S. R.

    2014-12-01

    Due to the serious scaling problems of the production in pipeline, Qingshui geothermal power plants closed after 12 years in the past. Because the pressure reduced in the process of upwelling, the hot spring from the reservoir will scaling CaCO3 immediately by large CO2 escape. This result will cause the space of pipeline reduced. On the other hand, as the temperature decreases, the SiO2 scaled in the part of heat exchanger. This study chose the Hongchailin and Qingshui IC-21 well as objects to simulate, and the Szeleng sandstone and the Lushan slate are the target layer of drilling well, respectively. We use pure water and saturated water pressure in our experiments. Besides, the previous studies showed that temperature of reservoir in Qingshui site was not over 300℃, so we set 300℃ as the upper limit temperature. The pressure was less than 800 bar by calculated the rock density of target layer. The original rock sample were placed in first autoclave, and added pure water in the second autoclave. Then we heat the first autoclave to reach the target temperature, and make the pressure saturated over water vapor pressure. After 72 hours the saturated water were leaked into the second autoclave. As the temperature cooling down, we removed the water from second autoclave and diluted the water. Finally, the Na+, K+, Mg+2, Ca+2 ions were analyzed by ICP. We want to get the maximum solubility of calcite and amorphous silica in equilibrium with sandstone and slate, and then check whether the method of geothermometer calculated is reasonable or not by calculated the concentration of Na+, K+, Si+4 in hot spring.

  8. Geothermal Energy.

    ERIC Educational Resources Information Center

    Conservation and Renewable Energy Inquiry and Referral Service (DOE), Silver Spring, MD.

    An introduction to geothermal energy is provided in this discussion of: (1) how a geothermal reservoir works; (2) how to find geothermal energy; (3) where it is located; (4) electric power generation using geothermal energy; (5) use of geothermal energy as a direct source of heat; (6) geopressured reservoirs; (7) environmental effects; (8)…

  9. An experiment in software reliability: Additional analyses using data from automated replications

    NASA Technical Reports Server (NTRS)

    Dunham, Janet R.; Lauterbach, Linda A.

    1988-01-01

    A study undertaken to collect software error data of laboratory quality for use in the development of credible methods for predicting the reliability of software used in life-critical applications is summarized. The software error data reported were acquired through automated repetitive run testing of three independent implementations of a launch interceptor condition module of a radar tracking problem. The results are based on 100 test applications to accumulate a sufficient sample size for error rate estimation. The data collected is used to confirm the results of two Boeing studies reported in NASA-CR-165836 Software Reliability: Repetitive Run Experimentation and Modeling, and NASA-CR-172378 Software Reliability: Additional Investigations into Modeling With Replicated Experiments, respectively. That is, the results confirm the log-linear pattern of software error rates and reject the hypothesis of equal error rates per individual fault. This rejection casts doubt on the assumption that the program's failure rate is a constant multiple of the number of residual bugs; an assumption which underlies some of the current models of software reliability. data raises new questions concerning the phenomenon of interacting faults.

  10. Passive, broad-band seismic measurements for geothermal exploration : The GAPSS experiment

    NASA Astrophysics Data System (ADS)

    Saccorotti, Gilberto; Piccinini, Davide; Zupo, Maria; Mazzarini, Francesco; Cauchie, Lena; Chiarabba, Claudio; Piana Agostinetti, Nicola

    2014-05-01

    Passive seismological imaging techniques based on either transient (earthquakes) or sustained (background noise) signals can provide detailed descriptions of subsurface attributes as seismic velocity, attenuation, and anisotropy. However, the correspondence between these parameters and the physical properties of crustal fluids is still ambiguous. Moreover, the resolving capabilities and condition of applicability of emerging techniques such as the Ambient Noise Tomography are still to be investigated thoroughly. Following these arguments, a specific project (GAPSS-Geothermal Area Passive Seismic Sources) was planned, in order to test passive exploration methods on a well-known geothermal area, namely the Larderello-Travale Geothermal Field (LTGF). This geothermal area is located in the western part of Tuscany (Italy), and it is the most ancient geothermal power field of the world. Heat flow in this area can reach local peaks of 1000 mW/m3. The deep explorations in this area showed a deeper reservoir (3000 to 4000 m depth) located within the metamorphic rocks in the contact aureole of the Pliocene-Quaternary granites; it is characterized by a wide negative gravimetric anomaly, interpreted as partially molten granite at temperatures of 800°C. From seismic surveys the K-marker K (pressurized horizons) was found at depths between 3 and 7 km. The structural grain of the geothermal field is characterized by N-W trending and N-E dipping normal faults whose activity lasts since the Pliocene. GAPSS lasted from early May, 2012, through October, 2013. It consisted of up to 20 temporary seismic stations, complemented by two permanent stations from the National Seismic Network of Italy. The resulting array has an aperture of about 50 Km, with station spacings between 2 and 50 km. Stations are equipped with either broadband (40s and 120s) or intermediate-period (5s), 3-components seismometers. LTGF is seismically active. During the first 10 months of measurements, we located

  11. A State Survey's Experience with the National Geothermal Database System: Lessons Learned to Improve Data Discovery, Access, and Stewardship

    NASA Astrophysics Data System (ADS)

    Hills, D. J.; Richard, S. M.

    2013-12-01

    State Geological Surveys in the U.S., in conjunction with the U.S. Geological Survey, have thousands of databases, directories, and 85,000+ geologic maps that collectively constitute a national geoscience data 'backbone' for research and practical applications. Much of this data has been at-risk in its current format or difficult to access. Organized by the Association of American State Geologists (AASG) with funding from the U.S. Department of Energy, the National Geothermal Data System (NGDS) has been able to make large quantities of geothermal-relevant geoscience data available to the public by creating a national, sustainable, distributed, and interoperable network of data providers. State Surveys or their equivalent have been instrumental to the success of the NGDS, but many have not had previous experience developing the necessary resources for credibility, sustainability, and interoperability beyond their area. The Geological Survey of Alabama (GSA) was no exception; here we expand upon some of the lessons the GSA has learned throughout this process, including a vision of a path forward. A major challenge that had to be overcome was the disconnect between interoperability requirements for the content models and the research interests of scientists providing the data. This was overcome by open and direct dialogue between the content developers and content providers. Although the iterative process could be frustrating at times, the result is a robust and thoroughly tested content model for geothermal data. This content model will provide an excellent starting point for other geoscience data content models. The greatest challenges the GSA encountered during the NGDS project were lack of standardization of our own data resources; lack of documentation; unknown quality of data; and lack of provenance of data. Moving forward, the GSA now has a model for stewardship of data, including what information and metadata should be collected to ensure future

  12. Designing Fault-Injection Experiments for the Reliability of Embedded Systems

    NASA Technical Reports Server (NTRS)

    White, Allan L.

    2012-01-01

    This paper considers the long-standing problem of conducting fault-injections experiments to establish the ultra-reliability of embedded systems. There have been extensive efforts in fault injection, and this paper offers a partial summary of the efforts, but these previous efforts have focused on realism and efficiency. Fault injections have been used to examine diagnostics and to test algorithms, but the literature does not contain any framework that says how to conduct fault-injection experiments to establish ultra-reliability. A solution to this problem integrates field-data, arguments-from-design, and fault-injection into a seamless whole. The solution in this paper is to derive a model reduction theorem for a class of semi-Markov models suitable for describing ultra-reliable embedded systems. The derivation shows that a tight upper bound on the probability of system failure can be obtained using only the means of system-recovery times, thus reducing the experimental effort to estimating a reasonable number of easily-observed parameters. The paper includes an example of a system subject to both permanent and transient faults. There is a discussion of integrating fault-injection with field-data and arguments-from-design.

  13. Experiments on different materials (polyamide, stainless & galvanized steel) influencing geothermal CaCO3 scaling formation: Polymorphs & elemental incorporation

    NASA Astrophysics Data System (ADS)

    Wedenig, Michael; Dietzel, Martin; Boch, Ronny; Hippler, Dorothee

    2016-04-01

    Thermal water is increasingly used for heat and electric power production providing base-load capable renewable and virtually unlimited geothermal energy. Compared to other energy sources geothermal facilities are less harmful to the environment, i.e. chemically and visually. In order to promote the economic viability of these systems compared to other traditional and renewable energy sources, production hindering processes such as corrosion and scaling of components arising from the typically high salinity thermal waters have to be considered as important economic factors. In this context, using proper materials being in contact with the thermal water is crucial and a playground for further improvements. Aim of the study presented, are basic experiments and observations of scaling and corrosive effects from hydrothermal water interacting with different materials and surfaces (stainless steel, polyamide, galvanized steel) and in particular the nucleation and growth effects of these materials regarding the precipitation of solid carbonate phases. The incorporation of Mg, Sr and Ba cations into the carbonate scalings are investigated as environmental proxy. For this purpose, hydrothermal carbonate precipitating experiments were initialized by mixing NaHCO3 and Ca-Mg-Sr-Ba-chloride solutions at temperatures ranging from 40 to 80 °C in glass reactors hosting artificial substrates of the above mentioned materials. The experiments show a strong dependence of the precipitation behaviour of calcium carbonate polymorphs on the particular material being present. Stainless steel and polyamide seem to restrict aragonite formation, whereas galvanized steel supports aragonite nucleation. Vaterite formation is promoted by polyamide surfaces. Importantly, vaterite is more soluble (less stable) compared to the other anhydrous calcium carbonate polymorphs, i.e. vaterite can be more easily re-dissolved. Thus, the use of polyamide components might reduce the amount and durability of

  14. Experience with modified aerospace reliability and quality assurance method for wind turbines

    NASA Technical Reports Server (NTRS)

    Klein, W. E.

    1982-01-01

    The SR&QA approach assures that the machine is not hazardous to the public or operating personnel, can operate unattended on a utility grid, demonstrates reliability operation, and helps establish the quality assurance and maintainability requirements for future wind turbine projects. The approach consisted of modified failure modes and effects analysis (FMEA) during the design phase, minimal hardware inspection during parts fabrication, and three simple documents to control activities during machine construction and operation. Five years experience shows that this low cost approach works well enough that it should be considered by others for similar projects.

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

    SciTech Connect

    Aki, K.

    1981-09-01

    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)

  16. Reliability Lessons Learned From GPU Experience With The Titan Supercomputer at Oak Ridge Leadership Computing Facility

    SciTech Connect

    Gallarno, George; Rogers, James H; Maxwell, Don E

    2015-01-01

    The high computational capability of graphics processing units (GPUs) is enabling and driving the scientific discovery process at large-scale. The world s second fastest supercomputer for open science, Titan, has more than 18,000 GPUs that computational scientists use to perform scientific simu- lations and data analysis. Understanding of GPU reliability characteristics, however, is still in its nascent stage since GPUs have only recently been deployed at large-scale. This paper presents a detailed study of GPU errors and their impact on system operations and applications, describing experiences with the 18,688 GPUs on the Titan supercom- puter as well as lessons learned in the process of efficient operation of GPUs at scale. These experiences are helpful to HPC sites which already have large-scale GPU clusters or plan to deploy GPUs in the future.

  17. Geothermal flux through palagonitized tephra, Surtsey, Iceland - The Surtsey temperature-data-relay experiment via Landsat-1

    NASA Technical Reports Server (NTRS)

    Friedman, J. D.; Preble, D. M.; Jakobsson, S.

    1976-01-01

    The net geothermal flux through palagonitized basaltic tephra rims of the Surtur I and Surtur II craters at Surtsey, Iceland, in 1972, is estimated at 780 plus or minus 325 microcal/sq cm/s, indicating a decline since 1969 when a flux of 1500 microcal/sq cm/s was estimated. Heat flux in this range characterizes the postvolcanic environment on Surtsey in which the subaerial polagonitization of basaltic tephra is associated with mass transfer of hydrothermal vapor, either of meteoric or sea-water origin, only a few years after cessation of eruptive activity. The flux estimation is the result of the Surtsey data-relay experiment via Landsat-1 which was carried out in several phases. Temperature data were transmitted for a 38-day period in November and December 1972. A near-surface vertical gradient of 69.4 C/m was obtained, suggesting a mixed mechanism of heat transfer, partitioned between conduction and convection.

  18. Multiphase, multicomponent simulations and experiments of reactive flow, relevant for combining geologic CO2 sequestration with geothermal energy capture

    NASA Astrophysics Data System (ADS)

    Saar, Martin O.

    2011-11-01

    Understanding the fluid dynamics of supercritical carbon dioxide (CO2) in brine- filled porous media is important for predictions of CO2 flow and brine displacement during geologic CO2 sequestration and during geothermal energy capture using sequestered CO2 as the subsurface heat extraction fluid. We investigate multiphase fluid flow in porous media employing particle image velocimetry experiments and lattice-Boltzmann fluid flow simulations at the pore scale. In particular, we are interested in the motion of a drop (representing a CO2 bubble) through an orifice in a plate, representing a simplified porous medium. In addition, we study single-phase/multicomponent reactive transport experimentally by injecting water with dissolved CO2 into rocks/sediments typically considered for CO2 sequestration to investigate how resultant fluid-mineral reactions modify permeability fields. Finally, we investigate numerically subsurface CO2 and heat transport at the geologic formation scale.

  19. Electrical conductivity of Icelandic deep geothermal reservoirs: insight from HT-HP laboratory experiments

    NASA Astrophysics Data System (ADS)

    Nono, Franck; Gibert, Benoit; Loggia, Didier; Parat, Fleurice; Azais, Pierre; Cichy, Sarah

    2016-04-01

    Although the Icelandic geothermal system has been intensively investigated over the years, targeting increasingly deeper reservoirs (i.e. under supercritical conditions) requires a good knowledge of the behaviour of physical properties of the host rock in order to better interpret large scale geophysical observations. In particular, the interpretation of deep electrical soundings remains controversial as only few studies have investigated the influence of altered minerals and pore fluid properties on electrical properties of rocks at high temperature and pressure. In this study, we investigate the electrical conductivity of drilled samples from different Icelandic geothermal fields at elevated temperature, confining pressure and pore pressure conditions (100°C < T < 600°C, confining pressure up to 100 MPa and pore pressure up to 35 MPa). The investigated rocks are composed of hyaloclastites, dolerites and basalts taken from depths of about 800 m for the hyaloclastites, to almost 2500 m for the dolerites. They display different porosity structures, from vuggy and intra-granular to micro-cracked porosities, and have been hydrothermally alterated in the chlorite to amphibolite facies. Electrical conductivity measurements are first determined at ambient conditions as a function of pore fluid conductivity in order to establish their relationships with lithology and pore space topology, prior to the high pressure and temperature measurements. Cementation factor varies from 1.5 for the dolerites to 2.83 for the basalt, reflecting changes in the shape of the conductive channels. The surface conductivities, measured at very low fluid conductivity, increases with the porosity and is correlated with the cation exchange capacity. At high pressure and temperature, we used the two guard-ring electrodes system. Measurements have been performed in dry and saturated conditions as a function of temperature and pore pressure. The supercritical conditions have been investigated and

  20. Volcanology and geothermal energy

    SciTech Connect

    Wohletz, K.; Heiken, G.

    1992-01-01

    The aim of this book is to demonstrate how volcanological concepts can be applied to the evaluation and exploration of geothermal energy resources. In regard to the geothermal content of the book, some of the information comes from the first-hand experience gained during the authors' exploration work in Middle America and with the Los Alamos Hot Dry Rock program. Other cases discussed come from classic geothermal systems in many regions and settings. The book begins with a summary of recent practical advances in volcanology, and then moves on to describe the considerable importance of pyroclastic rocks as a took to evaluate geothermal systems, including an in-depth treatment of hydrovolcanism. Following chapters deal with surface manifestations of geothermal systems, and systems associated with calderas, silicic lava domes, and basaltic volcanoes. The last chapter is on geothermal systems in maturing composite volcanoes. The Appendices include a broad overview of field methods in volcanic regions, volcanic rock classifications and properties, thermodynamic properties of water vapor (steam tables), and the use of cuttings in geothermal well logs. A two-dimensional heat flow code used for estimating geothermal resources is also given. The book makes two significant contributions: first, in its treatment of eruption dynamics, focusing on quantitative and theoretical analysis of volcanic processes, and second, in its comprehensive treatment of the fundamentals of hydrovolcanism, including fuel-coolant interactions and hydrofracturing.

  1. Geothermal pipeline

    SciTech Connect

    1997-08-01

    The Geothermal Pipeline is a progress and development update from the Geothermal Progress Monitor and includes brief descriptions of various geothermal projects around the world. The following topics are covered: The retirement of Geo-Heat Center Director Paul Lienau, announcement of two upcoming geothermal meetings, and a proposed geothermal power plant project in the Medicine Lake/Glass Mountain area of California. Also included is an article about the Bonneville Power Administration`s settlements with two California companies who had agreed to build geothermal power plants on the federal agency`s behalf, geothermal space heating projects and use of geothermal energy for raising red crayfish in Oregon, and some updates on geothermal projects in Minnesota, Pennsylvania, and China.

  2. Fluid-rock interactions in CO2-saturated, granite-hosted geothermal systems: Implications for natural and engineered systems from geochemical experiments and models

    NASA Astrophysics Data System (ADS)

    Lo Ré, Caroline; Kaszuba, John P.; Moore, Joseph N.; McPherson, Brian J.

    2014-09-01

    Hydrothermal experiments were conducted and geochemical models constructed to evaluate the geochemical and mineralogical response of fractured granite and granite + epidote in contact with thermal water, with and without supercritical CO2, at 250 °C and 25-45 MPa. Illite ± smectite ± zeolite(?) precipitate as secondary minerals at the expense of K-feldspar, oligoclase, and epidote. Illite precipitates in experiments reacting granite and granite + epidote with water; metastable smectite forms in the experiments injected with supercritical CO2. Waters are supersaturated with respect to quartz and saturated with respect to chalcedony in CO2-charged experiments, but neither mineral formed. Carbonate formation is predicted for experiments injected with supercritical CO2, but carbonate only formed during cooling and degassing of the granite + epidote + CO2 experiment. Experimental results provide insight into the buffering capacity of granites as well as the drivers of clay formation. Metastable smectite in the experiments is attributed to high water-rock ratios, high silica activities, and high CO2 and magnesium-iron concentrations. Smectite precipitation in supercritical CO2-bearing geothermal systems may affect reservoir permeability. Silicate formation may create or thicken caps within or on the edges of geothermal reservoirs. Carbonate formation, as desired for carbon sequestration projects coinciding with geothermal systems, may require extended periods of time; cooling and degassing of CO2-saturated waters leads to carbonate precipitation, potentially plugging near-surface production pathways.

  3. Recover Act. Verification of Geothermal Tracer Methods in Highly Constrained Field Experiments

    SciTech Connect

    Becker, Matthew W.

    2014-05-16

    The prediction of the geothermal system efficiency is strong linked to the character of the flow system that connects injector and producer wells. If water flow develops channels or “short circuiting” between injection and extraction wells thermal sweep is poor and much of the reservoir is left untapped. The purpose of this project was to understand how channelized flow develops in fracture geothermal reservoirs and how it can be measured in the field. We explored two methods of assessing channelization: hydraulic connectivity tests and tracer tests. These methods were tested at a field site using two verification methods: ground penetrating radar (GPR) images of saline tracer and heat transfer measurements using distributed temperature sensing (DTS). The field site for these studies was the Altona Flat Fractured Rock Research Site located in northeastern New York State. Altona Flat Rock is an experimental site considered a geologic analog for some geothermal reservoirs given its low matrix porosity. Because soil overburden is thin, it provided unique access to saturated bedrock fractures and the ability image using GPR which does not effectively penetrate most soils. Five boreholes were drilled in a “five spot” pattern covering 100 m2 and hydraulically isolated in a single bedding plane fracture. This simple system allowed a complete characterization of the fracture. Nine small diameter boreholes were drilled from the surface to just above the fracture to allow the measurement of heat transfer between the fracture and the rock matrix. The focus of the hydraulic investigation was periodic hydraulic testing. In such tests, rather than pumping or injection in a well at a constant rate, flow is varied to produce an oscillating pressure signal. This pressure signal is sensed in other wells and the attenuation and phase lag between the source and receptor is an indication of hydraulic connection. We found that these tests were much more effective than constant

  4. Geothermal Energy

    SciTech Connect

    Steele, B.C.; Harman, G.; Pitsenbarger, J.

    1996-02-01

    Geothermal Energy Technology (GET) announces on a bimonthly basis the current worldwide information available on the technologies required for economic recovery of geothermal energy and its use as direct heat or for electric power production.

  5. Geothermal Energy.

    ERIC Educational Resources Information Center

    Reed, Marshall J.

    1979-01-01

    During 1978, exploration for geothermal energy continued at the same moderately low level of the past few years in most countries. The U.S. is the only country where the development of geothermal energy depends on private industry. (BB)

  6. Geothermal systems

    NASA Technical Reports Server (NTRS)

    Mohl, C.

    1978-01-01

    Several tasks of JPL related to geothermal energy are discussed. The major task is the procurement and test and evaluation of a helical screw drive (wellhead unit). A general review of geothermal energy systems is given. The presentation focuses attention on geothermal reservoirs in California, with graphs and charts to support the discussion. Included are discussions on cost analysis, systems maintenance, and a comparison of geothermal and conventional heating and cooling systems.

  7. Idaho Geothermal Commercialization Program. Idaho geothermal handbook

    SciTech Connect

    Hammer, G.D.; Esposito, L.; Montgomery, M.

    1980-03-01

    The following topics are covered: geothermal resources in Idaho, market assessment, community needs assessment, geothermal leasing procedures for private lands, Idaho state geothermal leasing procedures - state lands, federal geothermal leasing procedures - federal lands, environmental and regulatory processes, local government regulations, geothermal exploration, geothermal drilling, government funding, private funding, state and federal government assistance programs, and geothermal legislation. (MHR)

  8. Geothermal Energy.

    ERIC Educational Resources Information Center

    Bufe, Charles Glenn

    1983-01-01

    Major activities, programs, and conferences in geothermal energy during 1982 are highlighted. These include first comprehensive national assessment of U.S. low-temperature geothermal resources (conducted by U.S. Geological Survey and Department of Energy), map production by U.S. Geological Survey, geothermal plant production, and others. (JN)

  9. Systematic study of cell isolation from bovine nucleus pulposus: Improving cell yield and experiment reliability.

    PubMed

    Lee, Juliana T Y; Cheung, Kenneth M C; Leung, Victor Y L

    2015-12-01

    Differences in matrix compositions in human nucleus pulposus (NP) clinical samples demand different cell isolation protocols for optimal results but there is no clear guide about this to date. Sub-optimal protocols may result in low cell yield, limited reliability of results or even failure of experiments. Cell yield, viability and attachment of cells isolated from bovine NP tissue with different protocols were estimated by cell counting, Trypan blue staining and cell culturing respectively. RNA was extracted from isolated cells and quantified by Nanodrop spectrometry and RT-qPCR. Higher collagenase concentration, longer digestion duration and pronase pre-treatment increased the cell yield. Cell viability remained high (<5% dead cells) even after 0.2% collagenase treatment for overnight. NP cells remained to have high ACAN, COL2A1, CDH2, KRT18, and KRT19 expression compared to muscle cells for different cell isolation conditions tested. Digestion by collagenase alone without the use of pronase could isolate cells from human degenerated NP tissue but clusters of cells were observed. We suggest the use of the disappearance of tissue as an indirect measure of cells released. This study provides a guide for researchers to decide the parameters involved in NP cell isolation for optimal outcome. PMID:26036782

  10. National Geothermal Data System

    NASA Astrophysics Data System (ADS)

    Anderson, A. F.; Cuyler, D.; Snyder, W. S.; Allison, M. L.; Blackwell, D. D.; Williams, C. F.

    2011-12-01

    The goal of the U.S. Department of Energy's National Geothermal Data System is to design, build, implement, deploy and populate a national, sustainable, distributed, interoperable network of data and service (application) providers. These providers will develop, collect, serve, and maintain geothermal-relevant data that operates as an integral component of NGDS. As a result the geothermal industry, the public, and policy makers will have access to consistent and reliable data, which in turn, reduces the amount of staff time devoted to finding, retrieving, integrating, and verifying information. With easier access to information, the high cost and risk of geothermal power projects (especially exploration drilling) is reduced. Five separate NGDS projects provide the data support, acquisition, and access to cyber infrastructure necessary to reduce cost and risk of the nation's geothermal energy strategy and US DOE program goals focused on the production and utilization of geothermal energy. The U.S DOE Office of Energy Efficiency and Renewable Energy Geothermal Technologies Program is developing the knowledge and data foundation necessary for discovery and development of large-scale energy production while the Buildings Technology Program is focused on other practical applications such as direct use and residential/commercial ground source heat pumps. The NGDS provides expanded reference and resource data for research and development activities (a subset of the US DOE goals) and includes data from across all fifty states and the nation's leading academic geothermal centers. Thus, the project incorporates not only high-temperature potential but also moderate and low-temperature locations incorporating US DOE's goal of adding more geothermal electricity to the grid. The program, through its development of data integration cyberinfrastructure, will help lead to innovative exploration technologies through increased data availability on geothermal energy capacity. Finally

  11. Shaker Table Experiments with Rare Earth Elements Sorption from Geothermal Brine

    SciTech Connect

    Gary Garland

    2015-07-21

    This dataset described shaker table experiments ran with sieved -50 +100 mesh media #1 in brine #1 that have 2ppm each of the 7 REE metals at different starting pH's of 3.5, 4.5, and 5.5. The experimental conditions are 2g media to 150mL of REE solution, at 70C.

  12. Measuring Educators' Attitudes and Beliefs about Evaluation: Construct Validity and Reliability of the Teacher Evaluation Experience Scale

    ERIC Educational Resources Information Center

    Reddy, Linda A.; Dudek, Christopher M.; Kettler, Ryan J.; Kurz, Alexander; Peters, Stephanie

    2016-01-01

    This study presents the reliability and validity of the Teacher Evaluation Experience Scale--Teacher Form (TEES-T), a multidimensional measure of educators' attitudes and beliefs about teacher evaluation. Confirmatory factor analyses of data from 583 teachers were conducted on the TEES-T hypothesized five-factor model, as well as on alternative…

  13. The Development of the Functional Literacy Experience Scale Based upon Ecological Theory (FLESBUET) and Validity-Reliability Study

    ERIC Educational Resources Information Center

    Özenç, Emine Gül; Dogan, M. Cihangir

    2014-01-01

    This study aims to perform a validity-reliability test by developing the Functional Literacy Experience Scale based upon Ecological Theory (FLESBUET) for primary education students. The study group includes 209 fifth grade students at Sabri Taskin Primary School in the Kartal District of Istanbul, Turkey during the 2010-2011 academic year.…

  14. An Experiment to Test Geophysical Methods For Monitoring Fluid Re-Injection at the Wairakei Geothermal Field, New Zealand

    NASA Astrophysics Data System (ADS)

    Jiracek, G. R.; Bowles-Martinez, E.; Feucht, D. W.; Ryan, J.; Caldwell, T. G.; Bannister, S. C.; Bertrand, T.; Bennie, S.; Bourguignon, S.

    2010-12-01

    The National Science Foundation (NSF) is supporting US students to participate in GNS Science’s geothermal research program supported by the New Zealand Government. The NSF international program aims to quick-start a new generation of geothermal-oriented US geophysics students who will be poised to be active participants and leaders in US geothermal energy development. This year’s project evaluated joint passive seismic and magnetotelluric (MT) field measurements to determine three-dimensional (3-D) reservoir characteristics during fluid withdrawal and re-injection. A preliminary test of the ability to achieve repeatable MT data in high noise locations was carried out in the Wairakei geothermal field using a 14-site base-line MT survey and repeat occupations at four sites. Different data processing schemes identified MT frequency bands where impedance phase tensor data were most sensitive to known variables such as daily solar source variations, wind, and drilling operations. Other frequency bands were identified where good MT repeatability will allow further tests. A streamlined method was developed for visualizing 3-D earthquake focal mechanisms resulting from production changes in geothermal reservoirs. The computer program allows spatial sorting of seismic events and thus subsurface fracture identification.

  15. Geothermal Energy

    SciTech Connect

    Steele, B.C.; Pichiarella, L.S.; Kane, L.S.; Henline, D.M.

    1995-01-01

    Geothermal Energy (GET) announces on a bimonthly basis the current worldwide information available on the technologies required for economic recovery of geothermal energy and its use as direct heat or for electric power production. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database during the past two months.

  16. Geothermal Energy.

    ERIC Educational Resources Information Center

    Nemzer, Marilyn; Page, Deborah

    This curriculum unit describes geothermal energy in the context of the world's energy needs. It addresses renewable and nonrenewable energy sources with an in-depth study of geothermal energy--its geology, its history, and its many uses. Included are integrated activities involving science, as well as math, social studies, and language arts.…

  17. Observations of Seismoeletric Signals Induced by a Hydro-fracturing Experiment in a Deep Geothermal Reservoir

    NASA Astrophysics Data System (ADS)

    Marquis, G.; Darnet, M.; Michelet, S.; Baria, R.

    2003-12-01

    During a hydro-fracturing experiment at the Soultz-sous-Forêts Hot Dry Rock site, more than 100,000 microseismic events of magnitude greater than -2.0 were induced by the continuous injection of 30,000 m3 of fresh water at 5 km depth. At the same time, we carried out monitoring of surface electric fields at a sampling rate of 2 kHz with two pairs of unpolarizable electrodes. After removal of the man-made noise, we observed strong electric field perturbations associated to the 48 microseismic events of magnitude greater than 1.8. Their maximum amplitude is 20 mV for the largest event (M = 2.7) while the background electrical noise is roughly 70 mV. The start of these electric perturbations coincides with the P-arrival time of the seismic waves at a depth of 1.5 km i.e. roughly half a second before the surface arrival time and their duration is about one second. As the sediments - granite interface is located at the same depth, the source of these electromagnetic signals could be an electroseismic conversion at this high acoustic impedance contrast. Moreover, a detailed analysis of the electric waveform reveals that several electric phases are arriving on the surface after the first pulse which may be caused by electroseismic conversions within the sediment layers. We did not however observe any electric field perturbations prior to rupture and the alleged first pulse associated with piezoelectric effect. It seems therefore that the prevailing effect when monitoring high-frequency (>= 1 Hz) synearthquake EM phenomena is seismoelectric.

  18. Corrosion reference for geothermal downhole materials selection

    SciTech Connect

    Ellis, P.F. II, Smith, C.C.; Keeney, R.C.; Kirk, D.K.; Conover, M.F.

    1983-03-01

    Geothermal downhole conditions that may affect the performance and reliability of selected materials and components used in the drilling, completion, logging, and production of geothermal wells are reviewed. The results of specific research and development efforts aimed at improvement of materials and components for downhole contact with the hostile physicochemical conditions of the geothermal reservoir are discussed. Materials and components covered are tubular goods, stainless steels and non-ferrous metals for high-temperature downhole service, cements for high-temperature geothermal wells, high-temperature elastomers, drilling and completion tools, logging tools, and downhole pumps. (MHR)

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

    SciTech Connect

    Aki, K.

    1980-09-01

    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)

  20. Tracing Injection Fluids in Engineered Geothermal Systems

    NASA Astrophysics Data System (ADS)

    Rose, P. E.; Leecaster, K.; Mella, M.; Ayling, B.; Bartl, M. H.

    2011-12-01

    The reinjection of produced fluids is crucial to the effective management of geothermal reservoirs, since it provides a mechanism for maintaining reservoir pressures while allowing for the disposal of a toxic byproduct. Tracers are essential to the proper location of injection wells since they are the only known tool for reliably characterizing the flow patterns of recirculated fluids. If injection wells are placed too close to production wells, then reinjected fluids do not have sufficient residence time to extract heat from the reservoir and premature thermal breakthrough results. If injection wells are placed too far away, then the reservoir risks unacceptable pressure loss. Several thermally stable compounds from a family of very detectable fluorescent organic compounds (the naphthalene sulfonates) were characterized and found to be effective for use as geothermal tracers. Through batch-autoclave reactions, their Arrhenius pseudo-first-order decay-rate constants were determined. An analytical method was developed that allows for the laboratory determination of concentrations in the low parts-per-trillion range. Field experiments in numerous geothermal reservoirs throughout the world have confirmed the laboratory findings. Whereas conservative tracers such as the naphthalene sulfonates are effective tools for indicating interwell flow patterns and for measuring reservoir pore volumes, 'reactive' tracers can be used to constrain fracture surface area, which is the effective area for heat extraction. This is especially important for engineered geothermal system (EGS) wells, since reactive tracers can be used to measure fracture surface area immediately after drilling and while the well stimulation equipment is still on site. The reactive properties of these tracers that can be exploited to constrain fracture surface area are reversible sorption, contrasting diffusivity, and thermal decay. Laboratory batch- and flow-reactor experiments in combination with numerical

  1. Modeling and Simulation of Reliability & Maintainability Parameters for Reusable Launch Vehicles using Design of Experiments

    NASA Technical Reports Server (NTRS)

    Unal, Resit; Morris, W. Douglas; White, Nancy H.; Lepsch, Roger A.

    2004-01-01

    This paper describes the development of a methodology for estimating reliability and maintainability distribution parameters for a reusable launch vehicle. A disciplinary analysis code and experimental designs are used to construct approximation models for performance characteristics. These models are then used in a simulation study to estimate performance characteristic distributions efficiently. The effectiveness and limitations of the developed methodology for launch vehicle operations simulations are also discussed.

  2. UP TO 100,000 RELIABLE STRONG GRAVITATIONAL LENSES IN FUTURE DARK ENERGY EXPERIMENTS

    SciTech Connect

    Serjeant, S.

    2014-09-20

    The Euclid space telescope will observe ∼10{sup 5} strong galaxy-galaxy gravitational lens events in its wide field imaging survey over around half the sky, but identifying the gravitational lenses from their observed morphologies requires solving the difficult problem of reliably separating the lensed sources from contaminant populations, such as tidal tails, as well as presenting challenges for spectroscopic follow-up redshift campaigns. Here I present alternative selection techniques for strong gravitational lenses in both Euclid and the Square Kilometre Array, exploiting the strong magnification bias present in the steep end of the Hα luminosity function and the H I mass function. Around 10{sup 3} strong lensing events are detectable with this method in the Euclid wide survey. While only ∼1% of the total haul of Euclid lenses, this sample has ∼100% reliability, known source redshifts, high signal-to-noise, and a magnification-based selection independent of assumptions of lens morphology. With the proposed Square Kilometre Array dark energy survey, the numbers of reliable strong gravitational lenses with source redshifts can reach 10{sup 5}.

  3. Health impacts of geothermal energy

    SciTech Connect

    Layton, D.W.; Anspaugh, L.R.

    1981-06-15

    The focus is on electric power production using geothermal resources greater than 150/sup 0/C because this form of geothermal energy utilization has the most serious health-related consequences. Based on measurements and experience at existing geothermal power plants, atmospheric emissions of noncondensing gases such as hydrogen sulfide and benzene pose the greatest hazards to public health. Surface and ground waters contaminated by discharges of spent geothermal fluids constitute another health hazard. It is shown that hydrogen sulfide emissions from most geothermal power plants are apt to cause odor annoyances among members of the exposed public - some of whom can detect this gas at concentrations as low as 0.002 parts per million by volume. A risk assessment model is used to estimate the lifetime risk of incurring leukemia from atmospheric benzene caused by 2000 MW(e) of geothermal development in California's Imperial Valley. The risk of skin cancer due to the ingestion of river water in New Zealand that is contaminated by waste geothermal fluids containing arsenic is also assessed. Finally, data on the occurrence of occupational disease in the geothermal industry are summarized briefly.

  4. Influence of shutdown phases on the microbial community composition and their effects on the operational reliability in a geothermal plant in the North German Basin

    NASA Astrophysics Data System (ADS)

    Westphal, Anke; Lerm, Stephanie; Miethling-Graff, Rona; Seibt, Andrea; Wolfgramm, Markus; Würdemann, Hilke

    2014-05-01

    Microbial activity can influence the dissolution and/or precipitation of minerals, as well as corrosion phenomena that may lead to a lower efficiency of engineered systems. To enhance the understanding of these processes, the microbial biocenosis in fluids produced from the cold well of a deep geothermal heat store located in the North German Basin (NGB) was characterized during normal plant operation and immediately after plant downtime phases. The microbial community composition was dominated by three different genera of sulphate reducing bacteria (SRB) and fermentative Halanaerobiaceae in the 46 ° C tempered fluids during regular operation, whereas after shut down phases sequences of sulphur oxidizing bacteria (SOB) were additionally detected. The detection of SOB is regarded as an indication of oxygen introduction into the well during the downtime phase. This corresponded to the higher redox potential of fluids taken directly after the restart of fluid production in the cold well. In addition to an extremely high particle loading rate after plant restart, a higher DNA content as well as an increase of specific gene copy numbers of SRB and SOB by a factor of 104 and 105 respectively were observed. Obviously stagnant conditions favored the enrichment of biomass and particles in the well. This is supported by the determination of a higher sulphate and hydrogen sulphide content in the fluids taken initially after plant restart. With increasing fluid production during the restart, SRB specific gene copy numbers decreased much slower than SOB specific gene copy numbers, which led to the assumption that SOB abundance is limited to the near wellbore area. Besides the absence of particle removal by fluid flow and the deposition of particles by sedimentation during the shut down phase, oxygen introduction and subsequent activity of SOB may also have favored microbial induced formation of precipitates in the well. It is quite likely that the interaction of SRB and SOB

  5. Combining water-rock interaction experiments with reaction path and reactive transport modelling to predict reservoir rock evolution in an enhanced geothermal system

    NASA Astrophysics Data System (ADS)

    Kuesters, Tim; Mueller, Thomas; Renner, Joerg

    2016-04-01

    Reliably predicting the evolution of mechanical and chemical properties of reservoir rocks is crucial for efficient exploitation of enhanced geothermal systems (EGS). For example, dissolution and precipitation of individual rock forming minerals often result in significant volume changes, affecting the hydraulic rock properties and chemical composition of fluid and solid phases. Reactive transport models are typically used to evaluate and predict the effect of the internal feedback of these processes. However, a quantitative evaluation of chemo-mechanical interaction in polycrystalline environments is elusive due to poorly constrained kinetic data of complex mineral reactions. In addition, experimentally derived reaction rates are generally faster than reaction rates determined from natural systems, likely a consequence of the experimental design: a) determining the rate of a single process only, e.g. the dissolution of a mineral, and b) using powdered sample materials and thus providing an unrealistically high reaction surface and at the same time eliminating the restrictions on element transport faced in-situ for fairly dense rocks. In reality, multiple reactions are coupled during the alteration of a polymineralic rocks in the presence of a fluid and the rate determining process of the overall reactions is often difficult to identify. We present results of bulk rock-water interaction experiments quantifying alteration reactions between pure water and a granodiorite sample. The rock sample was chosen for its homogenous texture, small and uniform grain size (˜0.5 mm in diameter), and absence of pre-existing alteration features. The primary minerals are plagioclase (plg - 58 vol.%), quartz (qtz - 21 vol.%), K-feldspar (Kfs - 17 vol.%), biotite (bio - 3 vol.%) and white mica (wm - 1 vol.%). Three sets of batch experiments were conducted at 200 ° C to evaluate the effect of reactive surface area and different fluid path ways using (I) powders of the bulk rock with

  6. Development of concepts for the management of shallow geothermal resources in urban areas - Experience gained from the Basel and Zaragoza case studies

    NASA Astrophysics Data System (ADS)

    García-Gil, Alejandro; Epting, Jannis; Mueller, Matthias H.; Huggenberger, Peter; Vázquez-Suñé, Enric

    2015-04-01

    In urban areas the shallow subsurface often is used as a heat resource (shallow geothermal energy), i.e. for the installation and operation of a broad variety of geothermal systems. Increasingly, groundwater is used as a low-cost heat sink, e.g. for building acclimatization. Together with other shallow geothermal exploitation systems significantly increased groundwater temperatures have been observed in many urban areas (urban heat island effect). The experience obtained from two selected case study cities in Basel (CH) and Zaragoza (ES) has allowed developing concepts and methods for the management of thermal resources in urban areas. Both case study cities already have a comprehensive monitoring network operating (hydraulics and temperature) as well as calibrated high-resolution numerical groundwater flow and heat-transport models. The existing datasets and models have allowed to compile and compare the different hydraulic and thermal boundary conditions for both groundwater bodies, including: (1) River boundaries (River Rhine and Ebro), (2) Regional hydraulic and thermal settings, (3) Interaction with the atmosphere under consideration of urbanization and (4) Anthropogenic quantitative and thermal groundwater use. The potential natural states of the considered groundwater bodies also have been investigated for different urban settings and varying processes concerning groundwater flow and thermal regimes. Moreover, concepts for the management of thermal resources in urban areas and the transferability of the applied methods to other urban areas are discussed. The methods used provide an appropriate selection of parameters (spatiotemporal resolution) that have to be measured for representative interpretations of groundwater flow and thermal regimes of specific groundwater bodies. From the experience acquired from the case studies it is shown that understanding the variable influences of the specific geological and hydrogeological as well as hydraulic and thermal

  7. The effect of physician experience on the measurement reliability of the Reimers’ hip migration percentage in children with cerebral palsy

    PubMed Central

    Analan, Pınar Doruk; Yilmaz, Emine Ece; Adam, Mehmet; Leblebici, Berrin

    2015-01-01

    [Purpose] Reimers’ hip migration percentage (MP) is commonly used to document the extent of hip displacement in children with cerebral palsy (CP). However, factors such as poor administration of pelvic radiographs, a lack of concentration, inexperience, or a busy clinical environment may result in variations in the MP measurements. The aim of this study was to compare the differences in the MP results of two physiatrists with varying levels of experience to determine the role of experience in the measurement’s accuracy. [Subjects and Methods] This retrospective study included 62 hip radiographs of 31 children with spastic CP. Two physiatrists with different experience levels calculated the baseline MP on two occasions six weeks apart. Correlations, intra- and inter-rater reliabilities, and differences in the MPs were compared. [Results] Correlations and inter- and intra-rater reliabilities of the measurements were excellent. There were no statistically significant intra- or inter-rater differences for either of the two measurement points. Inter-rater correlations for each session were 0.94. [Conclusion] Experience does not appear to be a factor in the evaluation of MP, and inter-rater differences do not cause problems regarding patient follow-up. Therefore, repeated pelvic radiographs are not necessary in the evaluation of MP in children with CP unless indicated. PMID:26644686

  8. Sahlgrenska Excess Skin Questionnaire (SESQ): a reliable questionnaire to assess the experience of excessive skin after weight loss.

    PubMed

    Biörserud, Christina; Nielsen, Christina; Staalesen, Trude; Elander, Anna; Olbers, Torsten; Olsén, Monika Fagevik

    2013-02-01

    There is a lack of knowledge and reliable measurement instruments to assess excess skin after massive weight loss. The purpose of this study was to test the reliability of a new self-administered questionnaire. A self-administered questionnaire, the Sahlgrenska Excess Skin Questionnaire (SESQ) was designed to assess excess skin after weight loss. The questionnaire includes 30 questions about demographic data, activity and daily life and excess skin on specific body parts and the body as a whole. Forward and backward translations were made by two independent professional translators, from Swedish to English and then back to Swedish. The questionnaire was tested on 10 patients from Sweden and England and was followed by an interview with each patient. Minor corrections were made. A test-retest was carried out to evaluate the reliability by sending the Swedish questionnaire to 46 subjects with weight loss after obesity surgery, dieting, or medication. The test-retest reliability of questions concerning activity and daily life between the two occasions had a Percentage Of Agreement (POA) of 49%-76% and a weighted Kappa of 0.44-0.78. The questions about the degree of excess skin on specific body parts had a POA of 50%-76% and a weighted Kappa of 0.53-0.81. Excess skin perceived as causing problems had a POA of 32%-57 %, an adjusted POA of 63%-87%, and an Intra-Class Correlation of 0.72-0.92. The SESQ is reliable for evaluating patients' experience of excess skin after massive weight loss. PMID:23190023

  9. Geothermal Information Dissemination and Outreach

    SciTech Connect

    Ted J. Clutter, Geothermal Resources Council Executive Director

    2005-02-18

    Project Purpose To enhance technological and topical information transfer in support of industry and government efforts to increase geothermal energy use in the United States (power production, direct use, and geothermal groundsource heat pumps). Project Work GRC 2003 Annual Meeting. The GRC convened the meeting on Oct. 12-15, 2003, at Morelia's Centro de Convenciones y ExpoCentro in Mexico under the theme, International Collaboration for Geothermal Energy in the Americas. The event was also sponsored by the Comision Federal de Electricidad. ~600 participants from more than 20 countries attended the event. The GRC convened a Development of Geothermal Projects Workshop and Geothermal Exploration Techniques Workshop. GRC Field Trips included Los Azufres and Paricutin Volcano on Oct. 11. The Geothermal Energy Association (Washington, DC) staged its Geothermal Energy Trade Show. The Annual Meeting Opening Session was convened on Oct. 13, and included the governor of Michoacan, the Mexico Assistant Secretary of Energy, CFE Geothermal Division Director, DOE Geothermal Program Manager, and private sector representatives. The 2003 Annual Meeting attracted 160 papers for oral and poster presentations. GRC 2004. Under the theme, Geothermal - The Reliable Renewable, the GRC 2004 Annual Meeting convened on Aug. 29-Sept. 1, 2004, at the Hyatt Grand Champions Resort at Indian Wells, CA. Estimated total attendance (including Trade Show personnel, guests and accompanying persons) was ~700. The event included a workshop, Geothermal Production Well Pump Installation, Operation and Maintenance. Field trips went to Coso/Mammoth and Imperial Valley/Salton Sea geothermal fields. The event Opening Session featured speakers from the U.S. Department of Energy, U.S. Department of the Interior, and the private sector. The Geothermal Energy Association staged its Geothermal Energy Trade Show. The Geothermal Education Office staged its Geothermal Energy Workshop. Several local radio and TV

  10. Early operating and reliability experience with the CEBAF DC magnet power supplies

    SciTech Connect

    Merz, W.; Flood, R.; Martin, E.J.; O'Sullivan, M.

    1996-08-01

    The CEBAF accelerator is a five pass, recirculating, CW electron linear accelerator. There are a total of nine recirculation arcs connecting the two linacs. Three experimental halls are serviced by the accelerator through separate transport channels. The magnet powering system for CEBAF consists of approximately 2000 independent control channels. About 1850 of these channels are low current, trim magnet power supplies. There are 28 higher power supplies used to energize the major bending elements. Over one hundred, 20 amp, active shunts are used to vary current in selected magnets in the major dipole strings. The majority of the magnetic elements are concentrated in the arcs and transport channels. The correction dipoles, quadrupoles and sextupoles are each powered individually be a dedicated trim power supply channel. The arc and extraction channel dipoles are powered in series strings by the high powered supplies, known locally at CEBAF as `box power supplies'. Arc loads consist of some 30--40 magnets in series. Transport channel, path length control doglegs and septa box power supplies have loads ranging from 1 to 10 magnets. Shunts are installed on virtually all loads where two or more magnets are in series. At this time, 95% of the power supplies are installed and commissioned. In the past twelve months, beginning in May 1994, approximately 1200 trim magnet power supplies have been checked out. During this same period approximately 22 box power supplies and 100 shunts have been made operational. Full operation of the equipment has only been under way since early 1995. While this operation is only just beginning, much has been learned based on the reliability performance seen so far. The remainder of this paper describes the systems mentioned, their reliability problems, the fixes implemented to date, and some plans for the future. 6 refs., 3 tabs.

  11. Early operating and reliability experience with the CEBAF DC magnet power supplies

    SciTech Connect

    Merz, W.; Flood, R.; Martin, E.J.; O`Sullivan, M.

    1996-08-01

    The CEBAF accelerator is a five pass, recirculating, CW electron linear accelerator. There are a total of nine recirculation arcs connecting the two linacs. Three experimental halls are serviced by the accelerator through separate transport channels. The magnet powering system for CEBAF consists of approximately 2000 independent control channels. About 1850 of these channels are low current, trim magnet power supplies. There are 28 higher power supplies used to energize the major bending elements. Over one hundred, 20 amp, active shunts are used to vary current in selected magnets in the major dipole strings. The majority of the magnetic elements are concentrated in the arcs and transport channels. The correction dipoles, quadrupoles and sextupoles are each powered individually be a dedicated trim power supply channel. The arc and extraction channel dipoles are powered in series strings by the high powered supplies, known locally at CEBAF as ``box power supplies``. Arc loads consist of some 30-40 magnets in series. Transport channel, path length control doglegs and septa box power supplies have loads ranging from 1 to 10 magnets. Shunts are installed on virtually all loads where two or more magnets are in series. At this time, 95{percent} of the power supplies are installed and commissioned. In the past twelve months, beginning in May 1994, approximately 1200 trim magnet power supplies have been checked out. During this same period approximately 22 box power supplies and 100 shunts have been made operational. Full operation of the equipment has only been under way since early 1995. While this operation is only just beginning, much has been learned based on the reliability performance seen so far. The remainder of this paper describes the systems mentioned, their reliability problems, the fixes implemented to date, and some plans for the future. 6 refs., 3 tabs.

  12. Fault-free behavior of reliable multiprocessor systems: FTMP experiments in AIRLAB

    NASA Technical Reports Server (NTRS)

    Clune, E.; Segall, Z.; Siewiorek, D.

    1985-01-01

    This report describes a set of experiments which were implemented on the Fault tolerant Multi-Processor (FTMP) at NASA/Langley's AIRLAB facility. These experiments are part of an effort to formulate and evaluate validation methodologies for fault-tolerant computers. This report deals with the measurement of single parameters (baselines) of a fault free system. The initial set of baseline experiments lead to the following conclusions: (1) The system clock is constant and independent of workload in the tested cases; (2) the instruction execution times are constant; (3) the R4 frame size is 40mS with some variation; (4) the frame stretching mechanism has some flaws in its implementation that allow the possibility of an infinite stretching of frame duration. Future experiments are planned. Some will broaden the results of these initial experiments. Others will measure the system more dynamically. The implementation of a synthetic workload generation mechanism for FTMP is planned to enhance the experimental environment of the system.

  13. Federal Geothermal Research Program Update - Fiscal Year 2004

    SciTech Connect

    Patrick Laney

    2005-03-01

    The Department of Energy (DOE) and its predecessors have conducted research and development (R&D) in geothermal energy since 1971. The Geothermal Technologies Program (GTP) works in partnership with industry to establish geothermal energy as an economically competitive contributor to the U.S. energy supply. Geothermal energy production, a $1.5 billion a year industry, generates electricity or provides heat for direct use applications. The technologies developed by the Geothermal Technologies Program will provide the Nation with new sources of electricity that are highly reliable and cost competitive and do not add to America's air pollution or the emission of greenhouse gases. Geothermal electricity generation is not subject to fuel price volatility and supply disruptions from changes in global energy markets. Geothermal energy systems use a domestic and renewable source of energy. The Geothermal Technologies Program develops innovative technologies to find, access, and use the Nation's geothermal resources. These efforts include emphasis on Enhanced Geothermal Systems (EGS) with continued R&D on geophysical and geochemical exploration technologies, improved drilling systems, and more efficient heat exchangers and condensers. The Geothermal Technologies Program is balanced between short-term goals of greater interest to industry, and long-term goals of importance to national energy interests. The program's research and development activities are expected to increase the number of new domestic geothermal fields, increase the success rate of geothermal well drilling, and reduce the costs of constructing and operating geothermal power plants. These improvements will increase the quantity of economically viable geothermal resources, leading in turn to an increased number of geothermal power facilities serving more energy demand. These new geothermal projects will take advantage of geothermal resources in locations where development is not currently possible or

  14. Federal Geothermal Research Program Update Fiscal Year 2004

    SciTech Connect

    Not Available

    2005-03-01

    The Department of Energy (DOE) and its predecessors have conducted research and development (R&D) in geothermal energy since 1971. The Geothermal Technologies Program (GTP) works in partnership with industry to establish geothermal energy as an economically competitive contributor to the U.S. energy supply. Geothermal energy production, a $1.5 billion a year industry, generates electricity or provides heat for direct use applications. The technologies developed by the Geothermal Technologies Program will provide the Nation with new sources of electricity that are highly reliable and cost competitive and do not add to America's air pollution or the emission of greenhouse gases. Geothermal electricity generation is not subject to fuel price volatility and supply disruptions from changes in global energy markets. Geothermal energy systems use a domestic and renewable source of energy. The Geothermal Technologies Program develops innovative technologies to find, access, and use the Nation's geothermal resources. These efforts include emphasis on Enhanced Geothermal Systems (EGS) with continued R&D on geophysical and geochemical exploration technologies, improved drilling systems, and more efficient heat exchangers and condensers. The Geothermal Technologies Program is balanced between short-term goals of greater interest to industry, and long-term goals of importance to national energy interests. The program's research and development activities are expected to increase the number of new domestic geothermal fields, increase the success rate of geothermal well drilling, and reduce the costs of constructing and operating geothermal power plants. These improvements will increase the quantity of economically viable geothermal resources, leading in turn to an increased number of geothermal power facilities serving more energy demand. These new geothermal projects will take advantage of geothermal resources in locations where development is not currently possible or

  15. Geothermal pipeline

    SciTech Connect

    Not Available

    1992-12-01

    A number of new ideas for geothermal power development and use have been proposed or initiated. British engineers have proposed using North Sea oil rigs as geothermal power stations. These stations would use the low temperature heat from the water that now occupies the former oil reservoirs to generate electricity. NASA recently retrofitted its engine test facility to enable it to use warm water from an underground aquifer as source water in a heat pump. A major policy guideline regarding electricity is issued by the California Energy Commission (CEC) every two years. This year, CEC appears to be revising its method for determining the total societal cost of various electricity supply options. The change may impact geothermal energy usage in a positive way. Virtually untapped geothermal resources in Preston, Idaho will be utilized for warm water catfish farming. Stockton State College in New Jersey will be the site of one of the nation's largest geothermal projects when it is completed in 1993. It is designed to satisfy the college's energy requirements at an estimated cost savings of $300,000 per year. Aquaculture projects using thermal springs are under consideration in Utah and Washington State. Utah may be the site of an alligator farm and Washington State is being considered for raising golden tilapia, a food fish.

  16. Geothermal energy

    NASA Astrophysics Data System (ADS)

    Manzella, A.

    2015-08-01

    Geothermal technologies use renewable energy resources to generate electricity and direct use of heat while producing very low levels of greenhouse-gas (GHG) emissions. Geothermal energy is stored in rocks and in fluids circulating in the underground. Electricity generation usually requires geothermal resources temperatures of over 100°C. For heating, geothermal resources spanning a wider range of temperatures can be used in applications such as space and district heating (and cooling, with proper technology), spa and swimming pool heating, greenhouse and soil heating, aquaculture pond heating, industrial process heating and snow melting. Geothermal technology, which has focused so far on extracting naturally heated steam or hot water from natural hydrothermal reservoirs, is developing to more advanced techniques to exploit the heat also where underground fluids are scarce and to use the Earth as a potential energy battery, by storing heat. The success of the research will enable energy recovery and utilization from a much larger fraction of the accessible thermal energy in the Earth's crust.

  17. Dimensions and reliability of a questionnaire for the evaluation of subjective experiences of health among patients in mental health services.

    PubMed

    Jormfeldt, Henrika; Svensson, Bengt; Arvidsson, Barbro; Hansson, Lars

    2008-01-01

    Even though the concept of health and its importance has been widely discussed in health care during recent decades, mental health services have been criticised for adopting a biomedical perspective, which does not sufficiently consider the concept of health. The aim of the present study was to investigate the psychometric properties of the Health Questionnaire, a newly developed questionnaire to measure patients' subjective experience of health in mental health services. A cross sectional study was performed using a sample of 139 outpatients in mental health services. A principal component analysis with varimax rotation was used to test the factor structure of the questionnaire. Cronbach's alpha was employed to test internal consistency and Cohen's Kappa assessed test-retest reliability. The final scale, which contained 22 items, derived from three factors (autonomy, social involvement, and comprehensibility) and showed a good reliability in terms of internal consistency. Test-retest reliability was moderate or better for 17 out of 22 items. The Health Questionnaire may enable further empirical studies on subjectively experienced health in mental health services and serve as a measure of outcome and to monitor quality of care. PMID:18214778

  18. A reliable pipelining protocol for the message service of the Mobile Satellite Experiment

    NASA Technical Reports Server (NTRS)

    Li, V. O. K.; Yan, T.-Y.

    1986-01-01

    This paper describes and analyzes a pipelining protocol for the data message communications of MSAT-X, a proposed experimental satellite-based mobile communications network. A demand assigned multiple access protocol using pure ALOHA for making reservation requests has been developed for MSAT-X under error-free assumptions. Preliminary propagation studies indicate that the short term bit error rate of satellite channels in a mobile environment can be as high as 0.001. Therefore, error-control schemes must be developed to ensure reliable transmissions. A retransmission scheme using selective repeat to minimize the end-to-end delay is proposed. Slotted ALOHA for making reservation requests is used to increase the overall system throughput. Since the number of channels available for reservation and data channels is essentially fixed for a given voice call blocking probability and a fixed call arrival rate, the analysis presented in this paper is also applicable to the integrated voice and data services of MSAT-X. Various operational scenarios have been investigated.

  19. Qualitative soil moisture assessment in semi-arid Africa: the role of experience and training on inter-rater reliability

    NASA Astrophysics Data System (ADS)

    Rinderer, M.; Komakech, H.; Müller, D.; Seibert, J.

    2015-03-01

    Soil and water management is particularly relevant in semi-arid regions to enhance agricultural productivity. During periods of water scarcity soil moisture differences are important indicators of the soil water deficit and are traditionally used for allocating water resources among farmers of a village community. Here we present a simple, inexpensive soil wetness classification scheme based on qualitative indicators which one can see or touch on the soil surface. It incorporates the local farmers' knowledge on the best soil moisture conditions for seeding and brick making in the semi-arid environment of the study site near Arusha, Tanzania. The scheme was tested twice in 2014 with farmers, students and experts (April: 40 persons, June: 25 persons) for inter-rater reliability, bias of individuals and functional relation between qualitative and quantitative soil moisture values. During the test in April farmers assigned the same wetness class in 46% of all cases while students and experts agreed in about 60% of all cases. Students who had been trained in how to apply the method gained higher inter-rater reliability than their colleagues with only a basic introduction. When repeating the test in June, participants were given improved instructions, organized in small sub-groups, which resulted in a higher inter-rater reliability among farmers. In 66% of all classifications farmers assigned the same wetness class and the spread of class assignments was smaller. This study demonstrates that a wetness classification scheme based on qualitative indicators is a robust tool and can be applied successfully regardless of experience in crop growing and education level when an in-depth introduction and training is provided. The use of a simple and clear layout of the assessment form is important for reliable wetness class assignments.

  20. Qualitative soil moisture assessment in semi-arid Africa - the role of experience and training on inter-rater reliability

    NASA Astrophysics Data System (ADS)

    Rinderer, M.; Komakech, H. C.; Müller, D.; Wiesenberg, G. L. B.; Seibert, J.

    2015-08-01

    Soil and water management is particularly relevant in semi-arid regions to enhance agricultural productivity. During periods of water scarcity, soil moisture differences are important indicators of the soil water deficit and are traditionally used for allocating water resources among farmers of a village community. Here we present a simple, inexpensive soil wetness classification scheme based on qualitative indicators which one can see or touch on the soil surface. It incorporates the local farmers' knowledge on the best soil moisture conditions for seeding and brick making in the semi-arid environment of the study site near Arusha, Tanzania. The scheme was tested twice in 2014 with farmers, students and experts (April: 40 persons, June: 25 persons) for inter-rater reliability, bias of individuals and functional relation between qualitative and quantitative soil moisture values. During the test in April farmers assigned the same wetness class in 46 % of all cases, while students and experts agreed on about 60 % of all cases. Students who had been trained in how to apply the method gained higher inter-rater reliability than their colleagues with only a basic introduction. When repeating the test in June, participants were given improved instructions, organized in small subgroups, which resulted in a higher inter-rater reliability among farmers. In 66 % of all classifications, farmers assigned the same wetness class and the spread of class assignments was smaller. This study demonstrates that a wetness classification scheme based on qualitative indicators is a robust tool and can be applied successfully regardless of experience in crop growing and education level when an in-depth introduction and training is provided. The use of a simple and clear layout of the assessment form is important for reliable wetness class assignments.

  1. Operational experience and reliability of the cryogenic systems for the TRISTAN insertion quadrupole magnets

    SciTech Connect

    Tsuchiya, K.; Ohuchi, N.; Morita, Y.; Kabe, A.

    1996-12-31

    Four sets of helium cryogenic systems for the mini-beta insertion quadrupole magnets were installed near the interaction points of the TRISTAN main ring in 1990. Each system consists of a helium compressor, a cold box, a subcooler, transfer lines, two magnet-cryostats, two helium gas tanks and a liquid nitrogen storage tank, and its nominal cooling capacity is 140 W at 4.2 K + 25 L/h. The four systems are controlled automatically by a process control computer system. The first operation started in 1991 and by the middle of 1995, the total operating time for each system reached about 28,000 hours. In this paper the authors report the experience gathered during 28,000 x 4 operating hours in running four cryogenic systems together with the control system. Maintenance experience and statistics of failures of different components are also described.

  2. Liver volumetry: Is imaging reliable? Personal experience and review of the literature.

    PubMed

    D'Onofrio, Mirko; De Robertis, Riccardo; Demozzi, Emanuele; Crosara, Stefano; Canestrini, Stefano; Pozzi Mucelli, Roberto

    2014-04-28

    The amount of the future liver remnant volume is fundamental for hepato-biliary surgery, representing an important potential risk-factor for the development of post-hepatectomy liver failure. Despite this, there is no uniform consensus about the amount of hepatic parenchyma that can be safely resected, nor about the modality that should be chosen for this evaluation. The pre-operative evaluation of hepatic volume, along with a precise identification of vascular and biliar anatomy and variants, are therefore necessary to reduce surgical complications, especially for extensive resections. Some studies have tried to validate imaging methods [ultrasound, computed tomography (CT), magnetic resonance imaging] for the assessment of liver volume, but there is no clear evidence about the most accurate method for this evaluation. Furthermore, this volumetric evaluation seems to have a certain degree of error, tending to overestimate the actual hepatic volume, therefore some conversion factors, which should give a more reliable evaluation of liver volume, have been proposed. It is widespread among non-radiologists the use of independent software for an off-site volumetric analysis, performed on digital imaging and communications in medicine images with their own personal computer, but very few studies have provided a validation of these methods. Moreover, while the pre-transplantation volumetric assessment is fundamental, it remains unclear whether it should be routinely performed in all patients undergoing liver resection. In this editorial the role of imaging in the estimation of liver volume is discussed, providing a review of the most recent literature and a brief personal series of correlations between liver volumes and resection specimens' weight, in order to assess the precision of the volumetric CT evaluation. PMID:24778768

  3. Liver volumetry: Is imaging reliable? Personal experience and review of the literature

    PubMed Central

    D’Onofrio, Mirko; De Robertis, Riccardo; Demozzi, Emanuele; Crosara, Stefano; Canestrini, Stefano; Pozzi Mucelli, Roberto

    2014-01-01

    The amount of the future liver remnant volume is fundamental for hepato-biliary surgery, representing an important potential risk-factor for the development of post-hepatectomy liver failure. Despite this, there is no uniform consensus about the amount of hepatic parenchyma that can be safely resected, nor about the modality that should be chosen for this evaluation. The pre-operative evaluation of hepatic volume, along with a precise identification of vascular and biliar anatomy and variants, are therefore necessary to reduce surgical complications, especially for extensive resections. Some studies have tried to validate imaging methods [ultrasound, computed tomography (CT), magnetic resonance imaging] for the assessment of liver volume, but there is no clear evidence about the most accurate method for this evaluation. Furthermore, this volumetric evaluation seems to have a certain degree of error, tending to overestimate the actual hepatic volume, therefore some conversion factors, which should give a more reliable evaluation of liver volume, have been proposed. It is widespread among non-radiologists the use of independent software for an off-site volumetric analysis, performed on digital imaging and communications in medicine images with their own personal computer, but very few studies have provided a validation of these methods. Moreover, while the pre-transplantation volumetric assessment is fundamental, it remains unclear whether it should be routinely performed in all patients undergoing liver resection. In this editorial the role of imaging in the estimation of liver volume is discussed, providing a review of the most recent literature and a brief personal series of correlations between liver volumes and resection specimens’ weight, in order to assess the precision of the volumetric CT evaluation. PMID:24778768

  4. Direct utilization of geothermal resources field experiments at Monroe, Utah. Final report, July 14, 1978-July 13, 1981

    SciTech Connect

    Blair, C.K.; Owen, L.B.

    1982-12-01

    The City of Monroe, Utah undertook a project to demonstrate the economic and technical viability of utilizing a low temperature geothermal resource to provide space and hot water heating to commercial, municipal, and domestic users within the community. During the course of the project, resource development and assessment, including drilling of a production well, was successfully completed. Upon completion of the field development and assessment phase of the program and of a preliminary design of the district heating system, it was determined that the project as proposed was not economically viable. This was due to: (1) a significant increase in estimated capital equipment costs resulting from the general inflation in construction costs, the large area/low population density in Monroe, and a more remote fluid disposal well site than planned, could not balance increased construction costs, (2) a lower temperature resource than predicted, and (3) due to predicted higher pumping and operating costs. After a thorough investigation of alternatives for utilizing the resource, further project activities were cancelled because the project was no longer economical and an alternative application for the resource could not be found within the constraints of the project. The City of Monroe, Utah is still seeking a beneficial use for the 600 gpm, 164/sup 0/F geothermal well. A summary of project activities included.

  5. Geothermal Energy.

    ERIC Educational Resources Information Center

    Eaton, William W.

    Described are the origin and nature of geothermal energy. Included is the history of its development as an energy source, technological considerations affecting its development as an energy source, its environmental effects, economic considerations, and future prospects of development in this field. Basic system diagrams of the operation of a…

  6. Session 19: Geothermal Materials Development

    SciTech Connect

    van Rooyen, Daniel

    1983-12-01

    Among the most pressing problems constraining the development of geothermal energy is the lack of satisfactory component and system reliability. This is due to the unavailability, on a commercial scale, of cost-effective materials that can function in a wide range of geothermal environments and to the unavailability of a comprehensive body of directly related test data or materials selection experience. In 1976, the GHTD started the Geothermal Materials Program to address materials-related problems, and since 1978 Brookhaven National Laboratory has provided technical and managerial assistance in the implementation of the effort. Major successes have been attained in the development of elastomers for high-temperature applications and in the use of polymer concrete liners for corrosion protection. Both technologies have been successfully transferred to industry. Current efforts in metallic and nonmetallic materials development and corrosion protection will be summarized. In the metals area, testing of a series of experimental stainless steels has led to compositions which show a very remarkable resistance to pitting corrosion in hot chloride electrolytes. Combinations of molybdenum and nitrogen are very beneficial. Alternate materials for line shaft pump bearings have been identified through tests in simulated hot brine. Cermets and carbides show promise of extending pump life. A series of drill bit steels has been examined for fatigue and hot fracture toughness. The work has indicated alloys with properties that exceed those of materials now in use. A major finding in the nonmetallic materials area has been the development of fluorinated elastomers for use in statis seals at temperatures greater than 300 C. Field testing has just commenced, but based upon laboratory results, the work is very promising. Commercialization of this material is underway. Technology transfer of a 240 C EPDM was completed earlier. Field testing of polymer concrete-lined pipe has been

  7. Geothermometer calculations for geothermal assessment

    USGS Publications Warehouse

    Reed, M.J.; Mariner, R.H.

    2007-01-01

    Geothermal exploration programs have relied on the calculation of geothermometers from hot spring chemistry as an early estimation of geothermal reservoir temperatures. Calibration of the geothermometers has evolved from experimental determinations of mineral solubility as a function of temperature to calibration from analyses of water chemistry from known depths and temperatures in thermal wells. Most of the geothermometers were calibrated from analyses of sodium-chloride type waters, and the application of some geothermometers should be restricted to waters of the chemical types that were used in their calibration. Chemical analyses must be determined to be reliable before they are used to calculate geothermometers. The USGS Geothermal Resource Assessment will rely on the silica geothermometer developed by Giggenbach that approximates the transition between chalcedony at 20??C and quartz at 200??C. Above 200??C, the assessment will rely on the quartz geothermometer. In addition, the assessment will also rely on the potassium-magnesium geothermometer.

  8. The drilling experience of K6-2, the high-temperature and crooked geothermal well in Kakkonda, Japan

    SciTech Connect

    Saito, S. )

    1993-06-01

    Well K6-2 was drilled for geothermal production for the Kakkonda No.2 Power Plant (to be built in 1995) at the Kakkonda geothermal field, northern Honshu Island, Japan from 1988 through 1989. The well was planned to be vertical and the target area was a 100-m radius of 2800 m. Mainly, because of the formation inclination, strong bit walk tendency was encountered below 1200 m. Even with packed-hole assemblies (BHA), the well inclination buildup rate was over 1 deg per 30 m. With this buildup rate, the well inclination would be over 50 deg at 2800 m, and not only miss the target area, but could not reach total depth because of severe rotation drag in the very abrasive formation (tertiary: shale, dacitic tuff and andesitic tuff-breccia; pre-tertiary: slate, sandstone and andesitic tuff). Because a pendulum BHA did not help to drop the inclination, downhole motors with bent subs were employed. Totals of six and seven downhole motors for 12 1/4 and 8 1/2-in. hole sections, respectively, were run. The estimated formation temperature was over 350[degree]C below 1900 m, so two mud cooling towers and 500 m[sup 3] pit were used to cool the returned mud. These systems worked well, but at 2245 m the estimated mud circulation temperature on bottom went up to 150[degree]C and the stator rubber of the downhole motors unbonded and broke up after a 1-h run. Below that depth, only a packed hole BHA was employed, and the inclination increased from 6 deg at 2300 m to 14 deg at 2800 m. At 2799 m, lost circulation was encountered and drilling terminated at 2818 m.

  9. Materials selection guidelines for geothermal energy utilization systems

    SciTech Connect

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

    1981-01-01

    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)

  10. Geothermal development opportunities in developing countries

    SciTech Connect

    Kenkeremath, D.C.

    1989-11-16

    This report is the proceedings of the Seminar on geothermal development opportunities in developing countries, sponsored by the Geothermal Division of the US Department of Energy and presented by the National Geothermal Association. The overall objectives of the seminar are: (1) Provide sufficient information to the attendees to encourage their interest in undertaking more geothermal projects within selected developing countries, and (2) Demonstrate the technological leadership of US technology and the depth of US industry experience and capabilities to best perform on these projects.

  11. Near-surface groundwater responses to injection of geothermal wastes

    SciTech Connect

    Arnold, S.C.

    1984-06-01

    This report assesses the feasibility of injection as an alternative for geothermal wastewater disposal and analyzes hydrologic controls governing the upward migration of injected fluids. Injection experiences at several geothermal developments are presented including the following: Raft River Valley, Salton Sea, East Mesa, Otake, Hatchobaru, and Ahuachapan geothermal fields.

  12. Geothermal tomorrow 2008

    SciTech Connect

    None, None

    2009-01-18

    Contributors from the Geothermal Technologies Program and the geothermal community highlight the current status and activities of the Program and the development of the global resource of geothermal energy.

  13. Geothermal probabilistic cost study

    NASA Technical Reports Server (NTRS)

    Orren, L. H.; Ziman, G. M.; Jones, S. C.; Lee, T. K.; Noll, R.; Wilde, L.; Sadanand, V.

    1981-01-01

    A tool is presented to quantify the risks of geothermal projects, the Geothermal Probabilistic Cost Model (GPCM). The GPCM model was used to evaluate a geothermal reservoir for a binary-cycle electric plant at Heber, California. Three institutional aspects of the geothermal risk which can shift the risk among different agents was analyzed. The leasing of geothermal land, contracting between the producer and the user of the geothermal heat, and insurance against faulty performance were examined.

  14. Geothermal probabilistic cost study

    SciTech Connect

    Orren, L.H.; Ziman, G.M.; Jones, S.C.; Lee, T.K.; Noll, R.; Wilde, L.; Sadanand, V.

    1981-08-01

    A tool is presented to quantify the risks of geothermal projects, the Geothermal Probabilistic Cost Model (GPCM). The GPCM model is used to evaluate a geothermal reservoir for a binary-cycle electric plant at Heber, California. Three institutional aspects of the geothermal risk which can shift the risk among different agents are analyzed. The leasing of geothermal land, contracting between the producer and the user of the geothermal heat, and insurance against faulty performance are examined. (MHR)

  15. Geothermal probabilistic cost study

    NASA Astrophysics Data System (ADS)

    Orren, L. H.; Ziman, G. M.; Jones, S. C.; Lee, T. K.; Noll, R.; Wilde, L.; Sadanand, V.

    1981-08-01

    A tool is presented to quantify the risks of geothermal projects, the Geothermal Probabilistic Cost Model (GPCM). The GPCM model was used to evaluate a geothermal reservoir for a binary-cycle electric plant at Heber, California. Three institutional aspects of the geothermal risk which can shift the risk among different agents was analyzed. The leasing of geothermal land, contracting between the producer and the user of the geothermal heat, and insurance against faulty performance were examined.

  16. Utility company views of geothermal development

    NASA Technical Reports Server (NTRS)

    Hinrichs, T. C.

    1974-01-01

    The views of geothermal development from a utility company standpoint are presented. The impediments associated with such developments as required reliability and identification of risks are discussed. The utility industry historically is not a risk-taking industry. Support of rapid geothermal development by the utility industry requires identification and elimination of risks or absorption of the risks by other agencies. Suggestions as to the identification and minimization of risks are made.

  17. Deep geothermal resources and energy: Current research and developments

    NASA Astrophysics Data System (ADS)

    Manzella, A.; Milsch, H.; Hahne, B.; van Wees, J. D.; Bruhn, D.

    2012-04-01

    Energy from deep geothermal resources plays an increasing role in many European countries in their efforts to increase the proportion of renewables in their energy portfolio. Deep geothermal heat and electric power have a high load factor, are sustainable and environmentally friendly. However, the safe, sustainable, and economic development of deep geothermal resources, also in less favourable regions, faces a number of issues requiring substantial research efforts: (1) The probability of finding an unknown geothermal reservoir has to be improved. (2) Drilling methods have to be better adapted and developed to the specific needs of geothermal development. (3) The assessment of the geothermal potential should provide more reliable and clear guidelines for the development. (4) Stimulation methods for enhanced geothermal systems (EGS) have to be refined to increase the success rate and reduce the risk associated with induced seismicity. (5) Operation and maintenance in aggressive geothermal environments require specific solutions for corrosion and scaling problems. (6) Last but not least, emerging activities to harness energy from supercritical reservoirs would make significant progress with qualified input from research. In particular, sedimentary basins like e.g. the North German and Polish Basin, the Pannonian Basin, the Po Valley, the Bavarian Molasse Basin or the Upper Rhine Graben have a high geothermal potential, even if geothermal gradients are moderate. We will highlight projects that aim at optimizing exploration, characterization, and modeling prior to drilling and at a better understanding of physical, hydraulic and chemical processes during operation of a geothermal power plant. This includes geophysical, geological and geochemical investigations regarding potential geothermal reservoirs in sedimentary basins, as well as modelling of geothermally relevant reservoir parameters that influence the potential performance and long-term behavior of a future

  18. Geothermal industry employment: Survey results & analysis

    SciTech Connect

    Not Available

    2005-09-01

    The Geothermal Energy Association (GEA) is ofteh asked about the socioeconomic and employment impact of the industry. Since available literature dealing with employment involved in the geothermal sector appeared relatively outdated, unduly focused on certain activities of the industry (e.g. operation and maintenance of geothermal power plants) or poorly reliable, GEA, in consultation with the DOE, decided to conduct a new employment survey to provide better answers to these questions. The main objective of this survey is to assess and characterize the current workforce involved in geothermal activities in the US. Several initiatives have therefore been undertaken to reach as many organizations involved in geothermal activities as possible and assess their current workforce. The first section of this document describes the methodology used to contact the companies involved in the geothermal sector. The second section presents the survey results and analyzes them. This analysis includes two major parts. The first part analyzes the survey responses, presents employment numbers that were captured and describes the major characteristics of the industry that have been identified. The second part of the analysis estimates the number of workers involved in companies that are active in the geothermal business but did not respond to the survey or could not be reached. Preliminary conclusions and the study limits and restrictions are then presented. The third section addresses the potential employment impact related to manufacturing and construction of new geothermal power facilities. Indirect and induced economic impacts related with such investment are also investigated.

  19. Geothermal Research and Development Program

    SciTech Connect

    Not Available

    1993-01-25

    Results are reported on adsorption of water vapor on reservoir rocks, physics of injection of water into vapor-dominated geothermal reservoirs, earth-tide effects on downhole pressures, injection optimization at the Geysers, effects of salinity in adsorption experiments, interpreting multiwell pressure data from Ohaaki, and estimation of adsorption parameters from transient experiments.

  20. Geothermal Progress Monitor 12

    SciTech Connect

    1990-12-01

    Some of the more interesting articles in this GPM are: DOE supporting research on problems at The Geysers; Long-term flow test of Hot Dry Rock system (at Fenton Hill, NM) to begin in Fiscal Year 1992; Significant milestones reached in prediction of behavior of injected fluids; Geopressured power generation experiment yields good results. A number of industry-oriented events and successes are reported, and in that regard it is noteworthy that this report comes near the end of the most active decade of geothermal power development in the U.S. There is a table of all operating U.S. geothermal power projects. The bibliography of research reports at the end of this GPM is useful. (DJE 2005)

  1. Geothermal reservoir simulation to enhance confidence in predictions for nuclear waste disposal

    SciTech Connect

    Kneafsey, Timothy J.; Pruess, Karsten; O'Sullivan, Michael J.; Bodvarsson, Gudmundur S.

    2002-06-15

    Numerical simulation of geothermal reservoirs is useful and necessary in understanding and evaluating reservoir structure and behavior, designing field development, and predicting performance. Models vary in complexity depending on processes considered, heterogeneity, data availability, and study objectives. They are evaluated using computer codes written and tested to study single and multiphase flow and transport under nonisothermal conditions. Many flow and heat transfer processes modeled in geothermal reservoirs are expected to occur in anthropogenic thermal (AT) systems created by geologic disposal of heat-generating nuclear waste. We examine and compare geothermal systems and the AT system expected at Yucca Mountain, Nevada, and their modeling. Time frames and spatial scales are similar in both systems, but increased precision is necessary for modeling the AT system, because flow through specific repository locations will affect long-term ability radionuclide retention. Geothermal modeling experience has generated a methodology, used in the AT modeling for Yucca Mountain, yielding good predictive results if sufficient reliable data are available and an experienced modeler is involved. Codes used in geothermal and AT modeling have been tested extensively and successfully on a variety of analytical and laboratory problems.

  2. City of El Centro geothermal energy utility core field experiment. Final report, February 16, 1979-November 30, 1984

    SciTech Connect

    Province, S.G.; Sherwood, P.B.

    1984-11-01

    The City of El Centro was awarded a contract in late 1978 to cost share the development of a low to moderate temperature geothermal resource in the City. The resource would be utilized to heat, cool and provide hot water to the nearby Community Center. In December 1981, Thermal 1 (injector) was drilled to 3970 feet. In January 1982, Thermal 2 (producer) was drilled to 8510 feet. Before testing began, fill migrated into both wells. Both wells were cleaned out. A pump was installed in the producer, but migration of fill again into the injector precluded injection of produced fluid. A short term production test was undertaken and results analyzed. Based upon the analysis, DOE decided that the well was not useful for commercial production due to a low flow rate, the potential problems of continued sanding and gasing, and the requirement to lower the pump setting depth and the associated costs of pumping. There was no commercial user found to take over the wells. Therefore, the wells were plugged and abandoned. The site was restored to its original condition.

  3. Geothermal Power Development in the Phillippines

    SciTech Connect

    Jovellanos, Jose U.; Alcaraz, Arturo; Datuin, Rogelio

    1980-12-01

    The generation of electric power to meet the needs of industrial growth and dispersal in the Philippines is aimed at attaining self-reliance through availment of indigenous energy resources. The Philippines by virtue of her position in the high-heat flow region has in abundance a number of exploitable geothermal fields located all over the country. Results indicate that the geothermal areas of the Philippines presently in various stages of exploration and development are of such magnitude that they can be relied on to meet a significant portion of the country's power need. Large scale geothermal energy for electric power generation was put into operation last year with the inauguration of two 55-MW geothermal generating units at Tiwi, Albay in Southern Luzon. Another two 55-MW units were added to the Luzon Grid in the same year from Makiling-Banahaw field about 70 kilometers south of Manila. For 1979 alone, therefore, 220-MW of generating capacity was added to the power supply coming from geothermal energy. This year a total of 220-MW power is programmed for both areas. This will bring to 443-MW of installed generating capacity from geothermal energy with 3-MW contributed by the Tongonan Geothermal pilot plant in Tongonan, Leyte, Central Philippines in operation since July 1977. Financial consideration of Philippine experience showed that electric power derived from geothermal energy is competitive with other sources of energy and is a viable source of baseload electric power. Findings have proven the technical and economic acceptability of geothermal energy resources development. To realize the benefits that stem from the utilization of indigenous geothermal resources and in the light of the country's ever increasing electric power demand and in the absence of large commercial oil discovery in the Philippines, geothermal energy resource development has been accelerated anew. The program includes development of eight fields by 1989 by adding five more fields to the

  4. Meta-Stable Magnetic Domain States That Prevent Reliable Absolute Palaeointensity Experiments Revealed By Magnetic Force Microscopy

    NASA Astrophysics Data System (ADS)

    de Groot, L. V.; Fabian, K.; Bakelaar, I. A.; Dekkers, M. J.

    2014-12-01

    Obtaining reliable estimates of the absolute palaeointensity of the Earth's magnetic field is notoriously difficult. Many methods to obtain paleointensities from suitable records such as lavas and archeological artifacts involve heating the samples. These heating steps are believed to induce 'magnetic alteration' - a process that is still poorly understood but prevents obtaining correct paleointensity estimates. To observe this magnetic alteration directly we imaged the magnetic domain state of titanomagnetite particles - a common carrier of the magnetic remanence in samples used for paleointensity studies. We selected samples from the 1971-flow of Mt. Etna from a site that systematically yields underestimates of the known intensity of the paleofield - in spite of rigorous testing by various groups. Magnetic Force Microscope images were taken before and after a heating step typically used in absolute palaeointensity experiments. Before heating, the samples feature distinct, blocky domains that sometimes seem to resemble a classical magnetite domain structure. After imparting a partial thermo-remanent magnetization at a temperature often critical to paleointensity experiments (250 °C) the domain state of the same titanomagnetite grains changes into curvier, wavy domains. Furthermore, these structures appeared to be unstable over time: after one-year storage in a magnetic field-free environment the domain states evolved into a viscous remanent magnetization state. Our observations may qualitatively explain reported underestimates from technically successful paleointensity experiments for this site and other sites reported previously. Furthermore the occurrence of intriguing observations such as 'the drawer storage effect' by Shaar et al (EPSL, 2011), and viscous magnetizations observed by Muxworthy and Williams (JGR, 2006) may be (partially) explained by our observations. The major implications of our study for all palaeointensity methods involving heating may be

  5. Microbiological monitoring in geothermal plants

    NASA Astrophysics Data System (ADS)

    Alawi, M.; Lerm, S.; Vetter, A.; Vieth, A.; Seibt, A.; Wolfgramm, M.; Würdemann, H.

    2009-12-01

    In times of increasing relevance of alternative energy resources the utilization of geothermal energy and subsurface energy storage gains importance and arouses increasing interest of scientists. The research project “AquiScreen” investigates the operational reliability of geothermally used groundwater systems under microbial, geochemical, mineralogical and petrological aspects. Microbiological analyses based on fluid and solid phases of geothermal systems are conducted to evaluate the impact of microbial populations on these systems. The presentation focuses on first results obtained from microbiological monitoring of geothermal plants located in two different regions of Germany: the North German Basin and the Molasse Basin in the southern part characterized by different salinities and temperatures. Fluid and filter samples taken during regular plant operation were investigated using genetic fingerprinting based on PCR-amplified 16S rRNA genes to characterize the microbial biocenosis of the geothermal aquifer. Sequencing of dominant bands of the fingerprints and the subsequent comparison to 16S rRNA genes from public databases enables a correlation to metabolic classes and provides information about the biochemical processes in the deep biosphere. The genetic profiles revealed significant differences in microbiological community structures of geothermal aquifers investigated. Phylogenetic analyses indicate broad metabolical diversity adapted to the specific conditions in the aquifers. Additionally a high amount of so far uncultivated microorganisms was detected indicating very specific indigenous biocenosis. However, in all geothermal plants bacteria were detected despite of fluid temperatures from 45° to 120°C. The identified microorganisms are closely related to thermophilic and hyperthermophilic species detectable in hot wells and hot springs, like Thermus scotoductus and Thermodesulfovibrio yellowstonii, respectively. Halophilic species were detected in

  6. Geothermal in transition

    SciTech Connect

    Anderson, J.L.

    1991-10-01

    This article examines the current market for geothermal projects in the US and overseas. The topics of the article include future capacity needs, upgrading the Coso Geothermal project, the productivity of the Geysers area of Northern California, the future of geothermal, and new projects at Soda Lake, Carson Basin, Unalaska Island, and the Puna Geothermal Venture in Hilo, Hawaii.

  7. Alaska geothermal bibliography

    SciTech Connect

    Liss, S.A.; Motyka, R.J.; Nye, C.J.

    1987-05-01

    The Alaska geothermal bibliography lists all publications, through 1986, that discuss any facet of geothermal energy in Alaska. In addition, selected publications about geology, geophysics, hydrology, volcanology, etc., which discuss areas where geothermal resources are located are included, though the geothermal resource itself may not be mentioned. The bibliography contains 748 entries.

  8. Geothermal Power Generation

    SciTech Connect

    2007-11-15

    The report provides an overview of the renewed market interest in using geothermal for power generation including a concise look at what's driving interest in geothermal power generation, the current status of geothermal power generation, and plans for the future. Topics covered in the report include: an overview of geothermal power generation including its history, the current market environment, and its future prospects; an analysis of the key business factors that are driving renewed interest in geothermal power generation; an analysis of the challenges that are hindering the implementation of geothermal power generation projects; a description of geothermal power generation technologies; a review of the economic drivers of geothermal power generation project success; profiles of the major geothermal power producing countries; and, profiles of the major geothermal power project developers.

  9. Stress control of seismicity patterns observed during hydraulic fracturing experiments at the Fenton Hill hot dry rock geothermal energy site, New Mexico

    SciTech Connect

    Fehler, M.C.

    1987-04-13

    Seismicity accompanying hydraulic injections into granitic rock is often diffuse rather than falling along a single plane. This diffuse zone of seismicity cannot be attributed to systematic errors in locations of the events. It has often been asserted that seismicity occurs along preexisting joints in the rock that are favorably aligned with the stress field so that slip can occur along them when effective stress is reduced by increasing pore fluid pressure. A new scheme for determining orientations and locations of planes along which the microearthquakes occurred was recently developed. The basic assumption of the method, called the three point method, is that many of the events fall along well defined planes; these planes are often difficult to identify visually in the data because planes of many orientations are present. The method has been applied to four hydraulic fracturing experiments conducted at Fenton Hill as part of a hot dry rock geothermal energy project. While multiple planes are found for each experiment; one plane is common to all experiments. The ratio of shear to normal stress along planes of all orientations is calculated using a best estimate of the current stress state at Fenton Hill. The plane common to all experiments has the highest ratio of shear to normal stress acting along it, so it is the plane most likely to slip. The other planes found by the three point method all have orientations with respect to current principal stresses that are favorable for slip to occur along preexisting planes of weakness. These results are consistent with the assertion that the rock contains pre-existing joints which slip when the effective stress is reduced by the increased pore fluid pressure accompanying the hydraulic injection. Microearthquakes occur along those planes that are favorably aligned with respect to the current stress field.

  10. Resource assessment for geothermal direct use applications

    SciTech Connect

    Beer, C.; Hederman, W.F. Jr.; Dolenc, M.R.; Allman, D.W.

    1984-04-01

    This report discusses the topic geothermal resource assessment and its importance to laymen and investors for finding geothermal resources for direct-use applications. These are applications where the heat from lower-temperature geothermal fluids, 120 to 200/sup 0/F, are used directly rather than for generating electricity. The temperatures required for various applications are listed and the various types of geothermal resources are described. Sources of existing resource data are indicated, and the types and suitability of tests to develop more data are described. Potential development problems are indicated and guidance is given on how to decrease technical and financial risk and how to use technical consultants effectively. The objectives of this report are to provide: (1) an introduction low-temperature geothermal resource assessment; (2) experience from a series of recent direct-use projects; and (3) references to additional information.

  11. Particle characterization for geothermal operations

    SciTech Connect

    Vetter, O.J.; Kandarpa, V.

    1981-01-06

    A detailed summary of an ongoing evaluation of existing particle measuring methodology with emphasis on (a) adapting of existing methods in geothermal operations and (b) further development of existing instrumentation for field use is presented. The various instruments and methods used and/or suggested for particle characterization are described in detail. Theoretical and practical aspects of particle characterizations are outlined. A plan for further laboratory and field experiments is outlined. The instrumentations to be selected after some additional lab and field tests will be used in the studies on (a) formation damage through particle invasion and (b) characterizing and monitoring of particle suspensions in geothermal operations.

  12. Maintaining a competitive geothermal industry

    SciTech Connect

    Zodiaco, V.P.

    1996-04-10

    I come to this geothermal business with over 30 years of experience in the power generation industry. I have earned my spurs (so to speak) in the electric utility, nuclear power, coal and the gas-fired cogeneration power businesses. I have been employed by Oxbow Power for the past seven years and for the past 18 months I have been based in Reno and responsible for the operation, maintenance and management of Oxbow`s domestic power projects which include three geothermal and two gas-fired facilities. The Oxbow Power Group (consisting principally of Oxbow Power Corporation, Oxbow Geothermal Corporation, Oxbow Power of Beowawe, Oxbow Power International and Oxbow Power Services, Inc.) is based in West Palm Beach, Florida, and has regional offices in Reno, Hong Kong and Manila to support on-line geothermal projects in Nevada, other domestic power projects and a geothermal plant under construction in the Philippines. Oxbow Power employs approximately 30 professionals in the development and management of power projects and over 100 supervisors and technicians in the operation and maintenance of power facilities. Current ownership in independent power projects total 340 MW in the United States and 47 MW under construction in the Philippines. Oxbow is currently negotiating additional projects in several Asian and Central American countries.

  13. Comparing a FACE experiment with mechanistic ecohydrological modeling: which processes are reliably simulated under elevated CO2?

    NASA Astrophysics Data System (ADS)

    Fatichi, S.; Leuzinger, S.

    2013-12-01

    Scenarios for the future terrestrial carbon and water cycle rely on numerical tools that simulate the dynamics of vegetation from assimilation of carbon through stomata to long-term forest development at the global scale. However, these tools are rarely tested to perform well in conditions different from the historical climate and comparisons are mostly limited to carbon and energy fluxes. A combination of numerical modeling and observations is used here to investigate the capability of a mechanistic approach to simulate the hydrology and the vegetation behavior of a forest exposed to elevated CO2 concentrations. Specifically, we thoroughly compare data from a free air CO2 enrichment (FACE) experiment in a mature deciduous forest in Switzerland with realizations from a state-of-the-art ecohydrological model (Tethys-Chloris). Model realizations compare favorably with field observations of photosynthesis, stomatal conductance, sap flow, leaf and fruit litter, as well as qualitative changes in soil moisture. The simulated differences between CO2 scenarios for both the carbon and water balance are generally very small (less than 10%) and fall within the uncertainty of experimental observations. More problematic is the simulation of stem growth which is significantly higher in the modeled scenario with elevated CO2 but not in the observations even though current accuracy of field measurements precludes robust conclusions. These results demonstrate that while ecohydrological models can be used to reliably simulate multi-year energy, water, and carbon fluxes, evaluating the modeled carbon allocation remains critical. However, experimental evidence suggests that the structure of current vegetation models which use the photosynthesized carbon to directly drive plant growth should be revised because plant tissue growth is very sensitive to direct controls of environmental variables, independently of the amount of assimilated carbon.

  14. Guidebook to Geothermal Finance

    SciTech Connect

    Salmon, J. P.; Meurice, J.; Wobus, N.; Stern, F.; Duaime, M.

    2011-03-01

    This guidebook is intended to facilitate further investment in conventional geothermal projects in the United States. It includes a brief primer on geothermal technology and the most relevant policies related to geothermal project development. The trends in geothermal project finance are the focus of this tool, relying heavily on interviews with leaders in the field of geothermal project finance. Using the information provided, developers and investors may innovate in new ways, developing partnerships that match investors' risk tolerance with the capital requirements of geothermal projects in this dynamic and evolving marketplace.

  15. The reliability and validity of the Turkish version of the Wijma Delivery Expectancy/Experience Questionnaire (W-DEQ) with pregnant women.

    PubMed

    Korukcu, O; Kukulu, K; Firat, M Z

    2012-04-01

    This methodological study was planned to translate the Wijma Delivery Expectancy/Experience Questionnaire (W-DEQ) into Turkish and to investigate its reliability for both nulliparous and parous women in Turkish population. A total of 660 healthy women with normal pregnancies at gestational ages of between 28 and 40 weeks were recruited. The internal consistency reliability (Cronbach's α) was used for determining the reliability of the W-DEQ. Construct validity was also determined utilizing the known-groups method. In this study, independent sample t-tests were used to compare the nulliparous and parous groups differing in known fear status. In order to test the construct of the W-DEQ, Beck Anxiety Inventory, Depression Anxiety and Stress Scale and Brief Measure of Worry Severity scales were chosen as these scales are expected to correlate with the W-DEQ. Analysis of the construct validity of the W-DEQ version A using Pearson's correlation coefficients was performed for both nulliparous and parous women separately. All the scales in both groups showed a statistically significant correlation with the W-DEQ. The alpha coefficient (0.89) is well above the 0.70 criterion for internal consistency reliability. Turkish form of Wijma Delivery Expectancy/Experience Questionnaire Version A was fixed as reliable and valid means to measure the level of fear of childbirth among Turkish pregnants. PMID:22260727

  16. Microbiological Monitoring in Geothermal Plants

    NASA Astrophysics Data System (ADS)

    Alawi, M.; Lerm, S.; Linder, R.; Vetter, A.; Vieth-Hillebrand, A.; Miethling-Graff, R.; Seibt, A.; Wolfgramm, M.; Wuerdemann, H.

    2010-12-01

    In the scope of the research projects “AquiScreen” and “MiProTherm” we investigated geothermally used groundwater systems under microbial, geochemical, mineralogical and petrological aspects. On one side an enhanced process understanding of engineered geothermal systems is mandatory to optimize plant reliability and economy, on the other side this study provides insights into the microbiology of terrestrial thermal systems. Geothermal systems located in the North German Basin and the Molasse Basin were analyzed by sampling of fluids and solid phases. The investigated sites were characterized by different temperatures, salinities and potential microbial substrates. The microbial population was monitored by the use of genetic fingerprinting techniques and PCR-cloning based on PCR-amplified 16S rRNA and dissimilatory sulfite reductase (DSR) genes. DNA-sequences of fingerprints and cloned PCR-products were compared to public databases and correlated with metabolic classes to provide information about the biogeochemical processes. In all investigated geothermal plants, covering a temperature range from 5° to 120°C, microorganisms were found. Phylogenetic gene analyses indicate a broad diversity of microorganisms adapted to the specific conditions in the engineered system. Beside characterized bacteria like Thermus scotoductus, Siderooxidans lithoautotrophicus and the archaeon Methanothermobacter thermoautotrophicus a high number of so far uncultivated microorganisms was detected. As it is known that - in addition to abiotic factors - microbes like sulfate-reducing bacteria (SRB) are involved in the processes of corrosion and scaling in plant components, we identified SRB by specific analyses of DSR genes. The SRB detected are closely related to thermotolerant and thermophilic species of Desulfotomaculum, Thermodesulfovibrio, Desulfohalobium and Thermodesulfobacterium, respectively. Overall, the detection of microbes known to be involved in biocorrosion and the

  17. GEOTHERM Data Set

    DOE Data Explorer

    DeAngelo, Jacob

    1983-01-01

    GEOTHERM is a comprehensive system of public databases and software used to store, locate, and evaluate information on the geology, geochemistry, and hydrology of geothermal systems. Three main databases address the general characteristics of geothermal wells and fields, and the chemical properties of geothermal fluids; the last database is currently the most active. System tasks are divided into four areas: (1) data acquisition and entry, involving data entry via word processors and magnetic tape; (2) quality assurance, including the criteria and standards handbook and front-end data-screening programs; (3) operation, involving database backups and information extraction; and (4) user assistance, preparation of such items as application programs, and a quarterly newsletter. The principal task of GEOTHERM is to provide information and research support for the conduct of national geothermal-resource assessments. The principal users of GEOTHERM are those involved with the Geothermal Research Program of the U.S. Geological Survey.

  18. Hot Dry Rock; Geothermal Energy

    SciTech Connect

    1990-01-01

    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

  19. Geothermal energy development

    SciTech Connect

    Butler, E.W.; Pick, J.B.

    1983-01-01

    This book studies the impact of geothermal energy development in Imperial County, California. An integrated assessment model for public policy is presented. Geothermal energy resources in Imperial County are identified. Population and employment studies project the impact of geothermal on demography and population movement in the county. A public opinion, and a leadership opinion survey indicate support for well-regulated geothermal development. Actual development events are updated. Finally, research conclusions and policy recommendations are presented.

  20. Geothermal district G1

    SciTech Connect

    Not Available

    1988-12-01

    Geothermal District G1 includes 37 northeastern California counties and six geothermal fields: Lake City, Susanville, Litchfield, Wendel, Amedee, and Casa Diablo. Electrical generation from geothermal resources occurs in three of the fields: Wendel, Amedee, and Casa Diablo. Low-temperature geothermal projects are underway throughout the district and are described in a road log format. The ten projects described are located at Big Bend, Glass Mountain, Bieber, Alturas, Cedarville, Lake City, Honey Lake Valley, Greenville, and in Sierra and Mono Counties.

  1. Geothermal exploration in Indonesia

    SciTech Connect

    Radja, V.T.

    1984-03-01

    Indonesia is blessed with geothermal resources. This fortunate aspect is directly related to the fact that the archipelago is an island arc created by a subduction zone. Evidence of geothermal activity is common throughout the Islands. Among the islands' many active volcanos are numerous geothermal phenomena. Almost half of the volcanic centers in Indonesia (88 out of 177 centers) contain fumarole and sulfatare features. A brief history of the exploration for geothermal energy in Indonesia is presented.

  2. Geothermal energy in Nevada

    SciTech Connect

    Not Available

    1980-01-01

    The nature of goethermal resources in Nevada and resource applications are discussed. The social and economic advantages of utilizing geothermal energy are outlined. Federal and State programs established to foster the development of geothermal energy are discussed. The names, addresses, and phone numbers of various organizations actively involved in research, regulation, and the development of geothermal energy are included. (MHR)

  3. National Geothermal Data System: Transforming the Discovery, Access, and Analytics of Data for Geothermal Exploration

    SciTech Connect

    Patten, Kim

    2013-05-01

    Compendium of Papers from the 38th Workshop on Geothermal Reservoir Engineering Stanford University, Stanford, California February 11-13, 2013 The National Geothermal Data System (NGDS) is a distributed, interoperable network of data collected from state geological surveys across all fifty states and the nation’s leading academic geothermal centers. The system serves as a platform for sharing consistent, reliable, geothermal-relevant technical data with users of all types, while supplying tools relevant for their work. As aggregated data supports new scientific findings, this content-rich linked data ultimately broadens the pool of knowledge available to promote discovery and development of commercial-scale geothermal energy production. Most of the up-front risks associated with geothermal development stem from exploration and characterization of subsurface resources. Wider access to distributed data will, therefore, result in lower costs for geothermal development. NGDS is on track to become fully operational by 2014 and will provide a platform for custom applications for accessing geothermal relevant data in the U.S. and abroad. It is being built on the U.S. Geoscience Information Network (USGIN) data integration framework to promote interoperability across the Earth sciences community. The basic structure of the NGDS employs state-of-the art informatics to advance geothermal knowledge. The following four papers comprising this Open-File Report are a compendium of presentations, from the 38th Annual Workshop on Geothermal Reservoir Engineering, taking place February 11-13, 2013 at Stanford University, Stanford, California. “NGDS Geothermal Data Domain: Assessment of Geothermal Community Data Needs,” outlines the efforts of a set of nationwide data providers to supply data for the NGDS. In particular, data acquisition, delivery, and methodology are discussed. The paper addresses the various types of data and metadata required and why simple links to existing

  4. Geothermal monitor report

    NASA Astrophysics Data System (ADS)

    1982-06-01

    Geothermal Progress Monitor Report No. 6 presents a state-by-state summary of the status of geothermal leasing, exploration, and development in major physiographic regions where geothermal resource potential has been identified. Recent state-specific activities are reported at the end of each state status report, while recent activities of a more general nature are summarized briefly in Part 2 of the report. A list of recent publications of potential interest to the geothermal community and a directory of contributors to the geothermal progress monitoring system are also included.

  5. Hawaii geothermal project

    NASA Technical Reports Server (NTRS)

    Kamins, R. M.

    1974-01-01

    Hawaii's Geothermal Project is investigating the occurrence of geothermal resources in the archipelago, initially on the Island of Hawaii. The state's interest in geothermal development is keen, since it is almost totally dependent on imported oil for energy. Geothermal development in Hawaii may require greater participation by the public sector than has been true in California. The initial exploration has been financed by the national, state, and county governments. Maximization of net benefits may call for multiple use of geothermal resources; the extraction of by-products and the application of treated effluents to agricultural and aquacultural uses.

  6. Turbodrilling in the Geothermal Environment

    SciTech Connect

    Herbert, P.

    1981-01-01

    Geothermal drilling, historically, has presented what seemed to be insurmountable barriers to the efficient and extended use of downhole drilling motors, especially those containing elastomeric bearing or motor components. In addition to being damaging to rubber, the typical temperatures of 177 to 371 C (350 to 700 F) create other operating problems as well. Recent innovations, specifically in turbodrill design, have opened heretofore unrealized potentials and allowed, for the first time, extended downhole drilling of geothermal wells. A considerable amount of experience has been obtained both in The Geysers and Imperial County areas of California primarily in directional drilling applications using insert, diamond, and polycrystallines diamond compact bits. Other hot-hole applications are currently being drilled successfully or planned in other states, both onshore and offshore. The turbodrill is devoid of any elastomers or other temperature-sensitive materials, hence, its capabilities are closely matched to the requirements of the industry. The bearing assembly can withstand the rigors found in the drilling of typical geothermal formations and provide the performance necessary to stay in the hole, thus providing increased penetration rates and, hence, more economical drilling. This paper presents case histories of recent turbodrill performances in all areas where used. Furthermore, data will be presented showing the performance of insert, diamond, and polycrystalline diamond bits as they relate to the turbodrill, together with forecasts as to the potential that turbodrills have to offer in accelerating and controlling the drilling of geothermal wells.

  7. Estimation of static formation temperatures in geothermal wells by using an artificial neural network approach

    NASA Astrophysics Data System (ADS)

    Bassam, A.; Santoyo, E.; Andaverde, J.; Hernández, J. A.; Espinoza-Ojeda, O. M.

    2010-09-01

    An artificial neural network (ANN) approach was used to develop a new predictive model for the calculation of static formation temperature (SFT) in geothermal wells. A three-layer ANN architecture was successfully trained using a geothermal borehole database, which contains "statistically normalised" SFT estimates. These estimates were inferred from seven analytical methods commonly used in geothermal industry. Bottom-hole temperature (BHT) measurements and shut-in times were used as main input variables for the ANN training. Transient temperature gradients were used as secondary variables. The Levenberg-Marquardt (LM) learning algorithm, the hyperbolic tangent sigmoid transfer function and the linear transfer function were used for the ANN optimisation. The best training data set was obtained with an ANN architecture composed by five neurons in the hidden layer, which made possible to predict the SFT with a satisfactory efficiency ( R2>0.95). A suitable accuracy of the ANN model was achieved with a percentage error less than ±5%. The SFTs predicted by the ANN model were statistically analyzed and compared with "true" SFTs measured in synthetic experiments and actual BHT logs collected in geothermal boreholes during long shut-in times. These data sets were processed both to validate the new ANN model and to avoid bias. The SFT estimates inferred from the ANN validation process were in good agreement ( R2>0.95) with the "true" SFT data reported for synthetic and field experiments. The results suggest that the new ANN model could be used as a practical tool for the reliable prediction of SFT in geothermal wells using BHT and shut-in time as input data only.

  8. Reference book on geothermal direct use

    SciTech Connect

    Lienau, P.J.; Lund, J.W.; Rafferty, K.; Culver, G.

    1994-08-01

    This report presents the direct uses of geothermal energy in the United States. Topics discussed include: low-temperature geothermal energy resources; energy reserves; geothermal heat pumps; geothermal energy for residential buildings; and geothermal energy for industrial usage.

  9. Geothermal Outreach and Project Financing

    SciTech Connect

    Elizabeth Battocletti

    2006-04-06

    The ?Geothermal Outreach and Project Financing? project substantially added to the understanding of geothermal resources, technology, and small business development by both the general public as well as those in the geothermal community.

  10. Rational Hydrogenation for Enhanced Mobility and High Reliability on ZnO-based Thin Film Transistors: From Simulation to Experiment.

    PubMed

    Xu, Lei; Chen, Qian; Liao, Lei; Liu, Xingqiang; Chang, Ting-Chang; Chang, Kuan-Chang; Tsai, Tsung-Ming; Jiang, Changzhong; Wang, Jinlan; Li, Jinchai

    2016-03-01

    Hydrogenation is one of the effective methods for improving the performance of ZnO thin film transistors (TFTs), which originate from the fact that hydrogen (H) acts as a defect passivator and a shallow n-type dopant in ZnO materials. However, passivation accompanied by an excessive H doping of the channel region of a ZnO TFT is undesirable because high carrier density leads to negative threshold voltages. Herein, we report that Mg/H codoping could overcome the trade-off between performance and reliability in the ZnO TFTs. The theoretical calculation suggests that the incorporation of Mg in hydrogenated ZnO decrease the formation energy of interstitial H and increase formation energy of O-vacancy (VO). The experimental results demonstrate that the existence of the diluted Mg in hydrogenated ZnO TFTs could be sufficient to boost up mobility from 10 to 32.2 cm(2)/(V s) at a low carrier density (∼2.0 × 10(18) cm(-3)), which can be attributed to the decreased electron effective mass by surface band bending. The all results verified that the Mg/H codoping can significantly passivate the VO to improve device reliability and enhance mobility. Thus, this finding clearly points the way to realize high-performance metal oxide TFTs for low-cost, large-volume, flexible electronics. PMID:26856932

  11. How to improve reliability in groundwater analysis: over a decade of experience with external quality control in field campaigns on volatile halogenated compounds.

    PubMed

    Dorgerloh, Ute; Becker, Roland; Lutz, Axel; Bremser, Wolfram; Hilbert, Sabine; Nehls, Irene

    2012-01-01

    The reliability in measurement results obtained during environmental monitoring is crucial for the assessment and further planning of remediation efforts on the respective contaminated sites by the responsible authorities. A case study concerned with groundwater contaminated with perchloroethylene, trichloroethylene and 1,1,2-trichlorotrifluoroethane including their degradation products which involves private contract laboratories and an independent provider of quality assurance (QA) is presented. The experience gained with biannual monitoring campaigns over 14 years indicates that the selection of contractors on basis of accreditation status and successful performance in interlaboratory comparisons are not sufficient. Rather the auditing of the contractors by the QA provider prior to each campaign and the crosschecking of selected monitoring samples by the QA provider led to a lasting improvement of reliability in the contractors' measurement results. A mean deviation of 20% from the reference value determined by the QA provider for the crosschecked samples was reached. PMID:22124383

  12. The geothermal power organization

    SciTech Connect

    Scholl, K.L.

    1997-12-31

    The Geothermal Power Organization is an industry-led advisory group organized to advance the state-of-the-art in geothermal energy conversion technologies. Its goal is to generate electricity from geothermal fluids in the most cost-effective, safe, and environmentally benign manner possible. The group achieves this goal by determining the Member`s interest in potential solutions to technological problems, advising the research and development community of the needs of the geothermal energy conversion industry, and communicating research and development results among its Members. With the creation and adoption of a new charter, the Geothermal Power Organization will now assist the industry in pursuing cost-shared research and development projects with the DOE`s Office of Geothermal Technologies.

  13. Geothermal policy development program: expediting the local geothermal permitting process

    SciTech Connect

    Not Available

    1981-07-01

    For a number of years, concerns have been raised about the length of time and the complexity involved in obtaining required permits in order to develop the geothermal resource at the Geysers. Perhaps the most important factor is jurisdiction. At the Geysers, all three levels of government - local, state, and federal - exercise significant authority over various aspects of geothermal development. In addition, several agencies within each governmental level play an active role in the permitting process. The present study is concerned primarily with the local permitting process, and the ways in which this process could be expedited. This report begins by looking at the local role in the overall permitting process, and then reviews the findings and conclusions that have been reached in other studies of the problem. This is followed by a case study evaluation of recent permitting experience in the four Geysers-Calistoga KGRA counties, and the report concludes by outlining several approaches to expediting the local permitting process.

  14. Geothermal Today - 2001

    SciTech Connect

    2001-08-01

    U.S. Department of Energy Geothermal Energy Program Highlights Partnering with Industry A New Power Source for Nevada Drilling Research Finding Geothermal Resources Small-Scale Geothermal Power Plants The Heat Beneath Your Feet R&D 100 Award Program in Review Milestones January 2000 The U.S. Department of Energy GeoPowering the West initiative was launched. February 2000 Grants totaling $4.8 million were awarded in six western states, primarily for development of reservoir exploration, character

  15. Geothermal drilling technology update

    SciTech Connect

    Glowka, D.A.

    1997-04-01

    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.

  16. Geothermal Today - 1999

    SciTech Connect

    2000-05-01

    U.S. Department of Energy 1999 Geothermal Energy Program Highlights The Hot Facts Getting into Hot Water Turning Waste water into Clean Energy Producing Even Cleaner Power Drilling Faster and Cheaper Program in Review 1999: The Year in Review JanuaryCal Energy announced sale of Coso geothermal power plants at China Lake, California, to Caithness Energy, for $277 million. U.S. Export-Import Bank completed a $50 million refinancing of the Leyte Geothermal Optimization Project in the Philippines. F

  17. Geothermal Life Cycle Calculator

    DOE Data Explorer

    Sullivan, John

    2014-03-11

    This calculator is a handy tool for interested parties to estimate two key life cycle metrics, fossil energy consumption (Etot) and greenhouse gas emission (ghgtot) ratios, for geothermal electric power production. It is based solely on data developed by Argonne National Laboratory for DOE’s Geothermal Technologies office. The calculator permits the user to explore the impact of a range of key geothermal power production parameters, including plant capacity, lifetime, capacity factor, geothermal technology, well numbers and depths, field exploration, and others on the two metrics just mentioned. Estimates of variations in the results are also available to the user.

  18. South Dakota geothermal resources

    SciTech Connect

    Lund, J.W.

    1997-12-01

    South Dakota is normally not thought of as a geothermal state. However, geothermal direct use is probably one of the best kept secrets outside the state. At present there are two geothermal district heating systems in place and operating successfully, a resort community using the water in a large swimming pool, a hospital being supplied with part of its heat, numerous geothermal heat pumps, and many individual uses by ranchers, especially in the winter months for heating residences, barns and other outbuildings, and for stock watering.

  19. Models of Geothermal Brine Chemistry

    SciTech Connect

    Nancy Moller Weare; John H. Weare

    2002-03-29

    Many significant expenses encountered by the geothermal energy industry are related to chemical effects. When the composition, temperature of pressure of the fluids in the geological formation are changed, during reservoir evolution, well production, energy extraction or injection processes, the fluids that were originally at equilibrium with the formation minerals come to a new equilibrium composition, temperature and pressure. As a result, solid material can be precipitated, dissolved gases released and/or heat lost. Most geothermal energy operations experience these phenomena. For some resources, they create only minor problems. For others, they can have serious results, such as major scaling or corrosion of wells and plant equipment, reservoir permeability losses and toxic gas emission, that can significantly increase the costs of energy production and sometimes lead to site abandonment. In future operations that exploit deep heat sources and low permeability reservoirs, new chemical problems involving very high T, P rock/water interactions and unknown injection effects will arise.

  20. Geothermal Heat Pump Benchmarking Report

    SciTech Connect

    1997-01-17

    A benchmarking study was conducted on behalf of the Department of Energy to determine the critical factors in successful utility geothermal heat pump programs. A Successful program is one that has achieved significant market penetration. Successfully marketing geothermal heat pumps has presented some major challenges to the utility industry. However, select utilities have developed programs that generate significant GHP sales. This benchmarking study concludes that there are three factors critical to the success of utility GHP marking programs: (1) Top management marketing commitment; (2) An understanding of the fundamentals of marketing and business development; and (3) An aggressive competitive posture. To generate significant GHP sales, competitive market forces must by used. However, because utilities have functioned only in a regulated arena, these companies and their leaders are unschooled in competitive business practices. Therefore, a lack of experience coupled with an intrinsically non-competitive culture yields an industry environment that impedes the generation of significant GHP sales in many, but not all, utilities.

  1. Operating experience feedback report: Reliability of safety-related steam turbine-driven standby pumps. Commercial power reactors, Volume 10

    SciTech Connect

    Boardman, J.R.

    1994-10-01

    This report documents a detailed analysis of failure initiators, causes and design features for steam turbine assemblies (turbines with their related components, such as governors and valves) which are used as drivers for standby pumps in the auxiliary feedwater systems of US commercial pressurized water reactor plants, and in the high pressure coolant injection and reactor core isolation cooling systems of US commercial boiling water reactor plants. These standby pumps provide a redundant source of water to remove reactor core heat as specified in individual plant safety analysis reports. The period of review for this report was from January 1974 through December 1990 for licensee event reports (LERS) and January 1985 through December 1990 for Nuclear Plant Reliability Data System (NPRDS) failure data. This study confirmed the continuing validity of conclusions of earlier studies by the US Nuclear Regulatory Commission and by the US nuclear industry that the most significant factors in failures of turbine-driven standby pumps have been the failures of the turbine-drivers and their controls. Inadequate maintenance and the use of inappropriate vendor technical information were identified as significant factors which caused recurring failures.

  2. Hawaiian direct-heat grants encourage geothermal creativity

    SciTech Connect

    Beck, A.G. )

    1988-12-01

    The Hawaiian Community Geothermal Technology Program is unique. Under its auspices, heat and other by-products of Hawaii's high-temperature HGP-A geothermal well and power plant are not wasted. Instead, they form the backbone of a direct-heat grant program that reaches into the local community and encourages community members to develop creative uses for geothermal energy. A by-product of this approach is a broadened local base of support for geothermal energy development. With the experimental and precommercial work completed, most of the original grantees are looking for ways to continue their projects on a commercial scale by studying the economics of using geothermal heat in a full-scale business and researching potential markets. A geothermal mini-park may be built near the research center. In 1988, a second round of projects was funded under the program. The five new projects are: Geothermal Aquaculture Project - an experiment with low-cost propagation of catfish species in geothermally heated tanks with a biofilter; Media Steam Sterilization and Drying - an application of raw geothermal steam to shredded, locally-available materials such as coconut husks, which would be used as certified nursery growing media; Bottom-Heating System Using Geothermal Power for Propagation - a continuation of Leilani Foliage's project from the first round of grants, focusing on new species of ornamental palms; Silica Bronze - the use of geothermal silica as a refractory material in casting bronze artwork; and Electro-deposition of Minerals in Geothermal Brine - the nature and possible utility of minerals deposited from the hot fluid.

  3. Geothermal energy in the western United States and Hawaii: Resources and projected electricity generation supplies. [Contains glossary and address list of geothermal project developers and owners

    SciTech Connect

    Not Available

    1991-09-01

    Geothermal energy comes from the internal heat of the Earth, and has been continuously exploited for the production of electricity in the United States since 1960. Currently, geothermal power is one of the ready-to-use baseload electricity generating technologies that is competing in the western United States with fossil fuel, nuclear and hydroelectric generation technologies to provide utilities and their customers with a reliable and economic source of electric power. Furthermore, the development of domestic geothermal resources, as an alternative to fossil fuel combustion technologies, has a number of associated environmental benefits. This report serves two functions. First, it provides a description of geothermal technology and a progress report on the commercial status of geothermal electric power generation. Second, it addresses the question of how much electricity might be competitively produced from the geothermal resource base. 19 figs., 15 tabs.

  4. Geothermal energy program summary

    SciTech Connect

    Not Available

    1990-01-01

    This document reviews Geothermal Energy Technology and the steps necessary to place it into service. Specific topics covered are: four types of geothermal resources; putting the resource to work; power generation; FY 1989 accomplishments; hard rock penetration; conversion technology; and geopressured brine research. 16 figs. (FSD)

  5. Geothermal Financing Workbook

    SciTech Connect

    Battocletti, E.C.

    1998-02-01

    This report was prepared to help small firm search for financing for geothermal energy projects. There are various financial and economics formulas. Costs of some small overseas geothermal power projects are shown. There is much discussion of possible sources of financing, especially for overseas projects. (DJE-2005)

  6. Geothermal energy: a brief assessment

    SciTech Connect

    Lunis, B.C.; Blackett, R.; Foley, D.

    1982-07-01

    This document includes discussions about geothermal energy, its applications, and how it is found and developed. It identifies known geothermal resources located in Western's power marketing area, and covers the use of geothermal energy for both electric power generation and direct applications. Economic, institutional, environmental, and other factors are discussed, and the benefits of the geothermal energy resource are described.

  7. Circum-Pacific geothermal energy use in 1990

    SciTech Connect

    D'Olier, W.L.

    1990-06-01

    Geothermal energy utilization in Pacific Ocean nations is conveniently measured by installed electrical generating capacity in gross megawatts (MW). Better perception of comparative achievements and outlook in 1990 is obtained by separately considering California's large Geysers installation of 2,044 MW. On this basis, the US, Mexico, El Salvador, and Nicaragua have approximately 1,630 MW of geothermal electric power established. In the western Pacific, the Philippines, New Zealand, Japan, and Indonesia have approximately 1,470 MW of power generation. Geothermal energy now provides about 3% of the electric power supply in California and Mexico and 8% in the Philippines. The 1990s will see continued growth of geothermal electric power especially in the Philippines and Mexico, which are pushing beyond existing capacities of 890 and 700 MW, respectively. Costa Rica has substantial initial geothermal power capacity under construction. In California a development surge closed the 1980 decade with 240 MW of new capacity at Coso Hot Springs and 242 MW of additional capacity in Imperial Valley. The US geothermal industry is now contending with a constrained power market and negative impacts of overdevelopment at The Geysers. However, several US geothermal companies now qualified in integrated resource development, electrical generation, and marketing are advantageously positioned for the next opening in the power market. Where sound production, injection, and reservoir management are practiced, geothermal reservoirs are supporting reliable, high performance electric power generation. New technologies are further reducing geothermal's low environmental profile, particularly minimizing emissions to atmosphere. Geothermal energy utilization should continue its steady growth in the Circum-Pacific during the 1990 decade.

  8. Report on the Hemodialysis Reliable Outflow (HeRO) experience in dialysis patients with central venous occlusions

    PubMed Central

    Wallace, Justin R.; Chaer, Rabih A.; Dillavou, Ellen D.

    2014-01-01

    Objective The Hemodialysis Reliable Outflow (HeRO) graft (Hemosphere/CryoLife Inc, Eden Prairie, Minn) has provided an innovative means to obtain hemodialysis access for patients with severe central venous occlusive disease. The outcomes of this novel treatment modality in a difficult population have yet to be clearly established. Methods A retrospective review of HeRO graft placement from June 2010 to January 2012 was performed. Patient hemodialysis access history, clinical complexity, complications, and outcomes were analyzed. Categoric data were described with counts and proportions, and continuous data with means, ranges and, when appropriate, standard deviations. Patency rates were analyzed using life-table analysis, and patency rate comparisons were made with a two-group proportion comparison calculator. Results HeRO graft placement was attempted 21 times in 19 patients (52% women), with 18 of 21 (86%) placed successfully. All but one was placed in the upper extremity. Mean follow-up after successful placement has been 7 months (range, 0–23 months). The primary indication for all HeRO graft placements except one was central vein occlusion(s) and need for arteriovenous access. Patients averaged 2.0 previous (failed) accesses and multiple catheters. Four HeRO grafts (24%), all in women, required ligation and removal for severe steal symptoms in the immediate postoperative period (P < .01 vs men). Three HeROs were placed above fistulas for rescue. All thrombosed <4 months, although the fistulas remained open. An infection rate of 0.5 bacteremic events per 1000 HeRO-days was observed. At a mean follow-up of 7 months, primary patency was 28% and secondary patency was 44%. The observed 12-month primary and secondary patency rates were 11% and 32%, respectively. Secondary patency was maintained in four patients for a mean duration of 10 months (range, 6–18 months), with an average of 4.0 ± 2.2 thrombectomies per catheter. Conclusions HeRO graft placement, when

  9. Advanced Geothermal Turbodrill

    SciTech Connect

    W. C. Maurer

    2000-05-01

    Approximately 50% of the cost of a new geothermal power plant is in the wells that must be drilled. Compared to the majority of oil and gas wells, geothermal wells are more difficult and costly to drill for several reasons. First, most U.S. geothermal resources consist of hot, hard crystalline rock formations which drill much slower than the relatively soft sedimentary formations associated with most oil and gas production. Second, high downhole temperatures can greatly shorten equipment life or preclude the use of some technologies altogether. Third, producing viable levels of electricity from geothermal fields requires the use of large diameter bores and a high degree of fluid communication, both of which increase drilling and completion costs. Optimizing fluid communication often requires creation of a directional well to intersect the best and largest number of fracture capable of producing hot geothermal fluids. Moineau motor stators made with elastomers cannot operate at geothermal temperatures, so they are limited to the upper portion of the hole. To overcome these limitations, Maurer Engineering Inc. (MEI) has developed a turbodrill that does not use elastomers and therefore can operate at geothermal temperatures. This new turbodrill uses a special gear assembly to reduce the output speed, thus allowing a larger range of bit types, especially tri-cone roller bits, which are the bits of choice for drilling hard crystalline formations. The Advanced Geothermal Turbodrill (AGT) represents a significant improvement for drilling geothermal wells and has the potential to significantly reduce drilling costs while increasing production, thereby making geothermal energy less expensive and better able to compete with fossil fuels. The final field test of the AGT will prepare the tool for successful commercialization.

  10. Health Services OutPatient Experience questionnaire: factorial validity and reliability of a patient-centered outcome measure for outpatient settings in Italy

    PubMed Central

    Coluccia, Anna; Ferretti, Fabio; Pozza, Andrea

    2014-01-01

    Purpose The patient-centered approach to health care does not seem to be sufficiently developed in the Italian context, and is still characterized by the biomedical model. In addition, there is a lack of validated outcome measures to assess outpatient experience as an aspect common to a variety of settings. The current study aimed to evaluate the factorial validity, reliability, and invariance across sex of the Health Services OutPatient Experience (HSOPE) questionnaire, a short ten-item measure of patient-centeredness for Italian adult outpatients. The rationale for unidimensionality of the measure was that it could cover global patient experience as a process common to patients with a variety of diseases and irrespective of the phase of treatment course. Patients and methods The HSOPE was compiled by 1,532 adult outpatients (51% females, mean age 59.22 years, standard deviation 16.26) receiving care in ten facilities at the Santa Maria alle Scotte University Hospital of Siena, Italy. The sample represented all the age cohorts. Twelve percent were young adults, 57% were adults, and 32% were older adults. Exploratory and confirmatory factor analyses were conducted to evaluate factor structure. Reliability was evaluated as internal consistency using Cronbach’s α. Factor invariance was assessed through multigroup analyses. Results Both exploratory and confirmatory analyses suggested a clearly defined unidimensional structure of the measure, with all the ten items having salient loadings on a single factor. Internal consistency was excellent (α=0.95). Indices of model fit supported a single-factor structure for both male and female outpatient groups. Young adult outpatients had significantly lower scores on perceived patient-centeredness relative to older adults. No significant difference emerged on patient-centeredness between male and female outpatients. Conclusion The HSOPE questionnaire seemed to be a tool with high acceptability and excellent psychometric

  11. Reliability training

    NASA Technical Reports Server (NTRS)

    Lalli, Vincent R. (Editor); Malec, Henry A. (Editor); Dillard, Richard B.; Wong, Kam L.; Barber, Frank J.; Barina, Frank J.

    1992-01-01

    Discussed here is failure physics, the study of how products, hardware, software, and systems fail and what can be done about it. The intent is to impart useful information, to extend the limits of production capability, and to assist in achieving low cost reliable products. A review of reliability for the years 1940 to 2000 is given. Next, a review of mathematics is given as well as a description of what elements contribute to product failures. Basic reliability theory and the disciplines that allow us to control and eliminate failures are elucidated.

  12. Novel approaches for an enhanced geothermal development of residential sites

    NASA Astrophysics Data System (ADS)

    Schelenz, Sophie; Firmbach, Linda; Shao, Haibing; Dietrich, Peter; Vienken, Thomas

    2015-04-01

    An ongoing technological enhancement drives an increasing use of shallow geothermal systems for heating and cooling applications. However, even in areas with intensive shallow geothermal use, planning of geothermal systems is in many cases solely based on geological maps, drilling databases, and literature references. Thus, relevant heat transport parameters are rather approximated than measured for the specific site. To increase the planning safety and promote the use of renewable energies in the domestic sector, this study investigates a novel concept for an enhanced geothermal development of residential neighbourhoods. This concept is based on a site-specific characterization of subsurface conditions and the implementation of demand-oriented geothermal usage options. Therefore, an investigation approach has been tested that combines non-invasive with minimum-invasive exploration methods. While electrical resistivity tomography has been applied to characterize the geological subsurface structure, Direct Push soundings enable a detailed, vertical high-resolution characterization of the subsurface surrounding the borehole heat exchangers. The benefit of this site-specific subsurface investigation is highlighted for 1) a more precise design of shallow geothermal systems and 2) a reliable prediction of induced long-term changes in groundwater temperatures. To guarantee the financial feasibility and practicability of the novel geothermal development, three different options for its implementation in residential neighbourhoods were consequently deduced.

  13. Lichens as bioindicators of geothermal air pollution in central Italy

    SciTech Connect

    Loppi, S.

    1996-11-01

    The suitability of lichens as bioindicators of geothermal air pollution was evaluated in central Italy. Fifty-one sites were sampled in the Travale-Radicondoli geothermal field, an area of about 15 km{sup 2}. Lichens on 1-5 trees per station were sampled, using 30 x 50 cm grids on tree boles, where lichens were most dense. Index of Atmospheric Purity (IAP) was calculated as the sum of the frequencies of all lichen species present at the station. Using automatic mapping programs, the area was divided into four air quality zones and the lowest IAP values were found within about 500 m of geothermal power plants. No direct measurements of air pollution are available for the whole study area, however, other studies show that air pollution levels (mercury, boron) fall with distance from a geothermal source. Also no substrate parameter (height, circumference, bark pH, and buffer capacity of the trees) discriminates between IAP zones. This suggests that air pollution arising from geothermal emissions is responsible for the zonation shown, with values for species richness and IAP rising with distance from geothermal installations. It is concluded that lichens are reliable bioindicators of geothermal pollution. 64 refs., 1 fig., 3 tabs.

  14. Navy Geothermal Plan

    SciTech Connect

    Not Available

    1984-12-01

    Domestic geothermal resources with the potential for decreasing fossil fuel use and energy cost exist at a significant number of Navy facilities. The Geothermal Plan is part of the Navy Energy R and D Program that will evaluate Navy sites and provide a technical, economic, and environmental base for subsequent resource use. One purpose of the program will be to provide for the transition of R and D funded exploratory efforts into the resource development phase. Individual Navy geothermal site projects are described as well as the organizational structure and Navy decision network. 2 figs.

  15. Geothermal aquaculture in Nevada

    SciTech Connect

    Birk, S.

    1987-06-01

    Work in geothermal aquaculture and vertically integrated agriculture is undertaken by Washoe Aquaculture Limited, Gourmet Prawnz Inc., General Managing Partners. This approach to agriculture is researched at the integrated Prototype Aquaculture Facility (IPAF) at Hobo Hot Springs, Nevada. The principal objective at the IPAF is to use geothermal aquifers to commercially raise food, plants, and ornamental fish. At the IPAF, the feasibility of geothermal aquaculture has been demonstrated. The company has implemented many demonstration projects, including the cultivation of freshwater prawns, native baitfish, exotic tropical species, and commercially important aquatic plants.

  16. Modeling the Risks of Geothermal Development

    SciTech Connect

    Golabi, K.; Nair, K.; Rothstein, S.; Sioshansi, F.

    1980-12-16

    Geothermal energy has emerged as a promising energy source in recent years and has received serious attention from developers and potential users. Despite the advantages of this resource, such as potential cost competitiveness, reliability, public acceptance, etc., the commercial development and use of geothermal energy has been slow. Impediments to the development of this resource include technical, financial, environmental and regulatory uncertainties. Since geothermal power is unique in that the generation facility is tied to a single fuel at a single site, these uncertainties are of particular concern to utility companies. The areas of uncertainty and potential risks are well known. This paper presents a method for quantifying the relevant uncertainties and a framework for aggregating the risks through the use of submodels. The objective submodels can be combined with subjective probabilities (when sufficient data is not available) to yield a probability distribution over a single criterion (levelized busbar cost) that can be used to compare the desirability of geothermal power development with respect to other alternatives.

  17. Geothermal Energy Summary

    SciTech Connect

    J. L. Renner

    2007-08-01

    Following is complete draft.Geothermal Summary for AAPG Explorer J. L. Renner, Idaho National Laboratory Geothermal energy is used to produce electricity in 24 countries. The United States has the largest capacity (2,544 MWe) followed by Philippines (1,931 MWe), Mexico (953 MWe), Indonesia (797 MWe), and Italy (791 MWe) (Bertani, 2005). When Chevron Corporation purchased Unocal Corporation they became the leading producer of geothermal energy worldwide with projects in Indonesia and the Philippines. The U. S. geothermal industry is booming thanks to increasing energy prices, renewable portfolio standards, and a production tax credit. California (2,244 MWe) is the leading producer, followed by Nevada (243 MWe), Utah (26 MWe) and Hawaii (30 MWe) and Alaska (0.4 MWe) (Bertani, 2005). Alaska joined the producing states with two 0.4 KWe power plants placed on line at Chena Hot Springs during 2006. The plant uses 30 liters per second of 75°C water from shallow wells. Power production is assisted by the availability of gravity fed, 7°C cooling water (http://www.yourownpower.com/) A 13 MWe binary power plant is expected to begin production in the fall of 2007 at Raft River in southeastern Idaho. Idaho also is a leader in direct use of geothermal energy with the state capital building and several other state and Boise City buildings as well as commercial and residential space heated using fluids from several, interconnected geothermal systems. The Energy Policy Act of 2005 modified leasing provisions and royalty rates for both geothermal electrical production and direct use. Pursuant to the legislation the Bureau of Land management and Minerals Management Service published final regulations for continued geothermal leasing, operations and royalty collection in the Federal Register (Vol. 72, No. 84 Wednesday May 2, 2007, BLM p. 24358-24446, MMS p. 24448-24469). Existing U. S. plants focus on high-grade geothermal systems located in the west. However, interest in non

  18. Outstanding Issues in the Assessment of Enhanced Geothermal Systems Resources

    NASA Astrophysics Data System (ADS)

    Williams, C.; Deangelo, J.

    2010-12-01

    The successful implementation of Enhanced Geothermal Systems (EGS) technology has the potential to dramatically expand both the magnitude and spatial extent of geothermal energy production, and the U.S. Geological Survey (USGS) has been working to develop a comprehensive EGS resource assessment for the United States. However, a number of outstanding scientific and technical issues must be resolved in order to ensure the accuracy and reliability of this assessment. Among these are determining those conditions under which it is possible to replicate the high average permeability (approximately 10-15 to 10-13 m2) characteristic of natural hydrothermal reservoirs, evaluating the likely heterogeneity of fracture permeability within EGS reservoirs and its influence on the geothermal recovery factor, Rg, which is defined as the ratio of produced thermal energy to the thermal energy contained in the stimulated volume comprising the reservoir, and improving estimates of temperature in the upper crust to better quantify the thermal energy available at those depths viable for EGS reservoir creation. Models for the development of fracture permeability from the shear slip along pre-existing natural fractures induced by hydraulic stimulation indicate that production from EGS reservoirs will be sensitive to the influence of effective stress and rock properties on the processes of shear fracture formation and closure. Calibration of model parameters with results from EGS field experiments and demonstration projects suggests that sufficient permeability may be difficult to attain through shear stimulation at depths greater than approximately 6 km, particularly in regions characterized by high normal stress on pre-existing faults and fractures. In addition, the expected heterogeneity of fracture permeability within EGS reservoirs may limit Rg to values on the order of 0.05 to 0.1, which is at the lower end of the observed range for producing natural geothermal reservoirs. Although

  19. Geothermal energy research in Kenya: a review

    NASA Astrophysics Data System (ADS)

    Tole, Mwakio P.

    1996-11-01

    Geothermal energy for electricity generation is likely to become increasingly important in Kenya in the future. There are numerous centres of thermal activity in Kenya, particularly within the Rift Valley, although aridity and, consequently, availability of water may be a constraint to the development of large scale natural hydrothermal systems. Geothermal resources in the islands of Lake Turkana and those close to other rift lakes deserve further investigation as they do not suffer from the constraints of a shortage of water. The experience gained so far at Oikaria shows that environmental problems can be adequately addressed, though constant monitoring is necessary. H 2S emissions preclude the setting up of permanent residences within about 5 km of the geothermal power stations. Trace elements and radiation from geothermal fluids need to be monitored with respect to their impacts on plants and animals. The impact on the local hydrogeology also requires close observation. Multistage uses of geothermal fluids will greatly increase the benefits derived from this resource.

  20. Use of a Reliable Homemade Dilatometer To Study the Kinetics of the Radical Chain Polymerization of PMMA: An Undergraduate Polymer Chemistry Laboratory Kinetics Experiment

    NASA Astrophysics Data System (ADS)

    Mendicuti, Francisco; Martín, Olga; Tarazona, Maria Pilar

    1998-11-01

    In this laboratory experiment, a simple, reliable homemade dilatometer was used to study the kinetics of the radical chain polymerization of PMMA. The reaction was carried out in toluene with benzoyl peroxide as the initiator at a temperature of 80 °C. Each student studied the kinetics at a different initiator concentration constant. Pseudo-first-order plots permit students to obtain kapp and to demonstrate order 1 with respect to the monomer concentration. Finally, a log-log plot of kapp versus the initiator concentration from the data collected by each student demonstrates order 0.5 with respect to the initiator concentration. Results also agree with the rate constants of the process implicated in this type of polymerization.

  1. {open_quotes}Full steam ahead{close_quotes} (a historical review of geothermal power development in the Philippines)

    SciTech Connect

    Gazo, F.M.

    1997-12-31

    The Philippine geothermal energy development is now considered in a state of maturity. After more than 20 years of geothermal experience, the total geothermal installed capacity in the Philippines reached 1,455 MW (1996) or about 12% of the total installed power plant capacity. This also enabled the Philippines to become the second largest producer of geothermal energy in the world. The country`s track record in harnessing geothermal energy is considered a revelation, as it continues with its vision of {open_quotes}full steam ahead{close_quotes}, originally conceived when commercial geothermal operation started in 1973. It is thus proper and timely to refer to historical highlights and experiences in geothermal energy development for planning and implementation of the country`s geothermal energy program.

  2. New Zealand geothermal: Wairakei -- 40 years

    SciTech Connect

    1998-09-01

    This quarterly bulletin highlights the geothermal developments in New Zealand with the following articles: A brief history of the Wairakei geothermal power project; Geothermal resources in New Zealand -- An overview; Domestic and commercial heating and bathing -- Rotorua area; Kawerau geothermal development: A case study; Timber drying at Kawerau; Geothermal greenhouses at Kawerau; Drying of fibrous crops using geothermal steam and hot water at the Taupo Lucerne Company; Prawn Park -- Taupo, New Zealand; Geothermal orchids; Miranda hot springs; and Geothermal pipeline.

  3. Geothermal Program Review X: proceedings. Geothermal Energy and the Utility Market -- the Opportunities and Challenges for Expanding Geothermal Energy in a Competitive Supply Market

    SciTech Connect

    Not Available

    1992-01-01

    Each year the Geothermal Division of the US Department of Energy conducts an in-depth review of its entire geothermal R&D program. The conference serves several purposes: a status report on current R&D activities, an assessment of progress and problems, a review of management issues, and a technology transfer opportunity between DOE and the US geothermal city. This year`s conference, Program Review X, was held in San Francisco on March 24--26, 1992. The theme of the review, ``Geothermal Energy and the Utility Market -- The Opportunities and Challenges for Expanding Geothermal Energy in a Competitive Supply Market,`` focused on the needs of the electric utility sector. Geothermal energy, with its power capacity potential of 10 GWe by the year 2010, can provide reliable, enviromentally clean electricity which can help offset the projected increase in demand. Program Review X consisted of seven sessions including an opening session with presentations by Mr. Vikram Budhraja, Vice President of System Planning and Operations, Southern California Edison Company, and Mr. Richard Jaros, President and Chief Operating Officer, California Energy Company. The six technical sessions included presentations by the relevant field researchers covering DOE-sponsored R&D in hydrothermal, hot dry rock, and geopressured energy. Individual projects are processed separately for the data bases.

  4. Geothermal drilling technology

    SciTech Connect

    Dunn, J.C.; Livesay, B.J.

    1986-01-01

    The report discusses the current state of geothermal drilling technology with reference to how individual technology items are influenced by the following problem areas: high temperature; lost circulation; abrasive rocks; and corrosive gases. (ACR)

  5. Geothermal District Heating Economics

    Energy Science and Technology Software Center (ESTSC)

    1995-07-12

    GEOCITY is a large-scale simulation model which combines both engineering and economic submodels to systematically calculate the cost of geothermal district heating systems for space heating, hot-water heating, and process heating based upon hydrothermal geothermal resources. The GEOCITY program simulates the entire production, distribution, and waste disposal process for geothermal district heating systems, but does not include the cost of radiators, convectors, or other in-house heating systems. GEOCITY calculates the cost of district heating basedmore » on the climate, population, and heat demand of the district; characteristics of the geothermal resource and distance from the distribution center; well-drilling costs; design of the distribution system; tax rates; and financial conditions.« less

  6. Geothermal Orientation Handbook

    SciTech Connect

    1984-07-01

    This is a useful overview of the Department of Energy's outlook on geothermal energy development in the U.S. as of late 1983. For example, Exhibit 4 shows how electric utility planners' estimates of likely amounts of geothermal power on line for 1990 and 2000 first increased and then declined over time as they were surveyed in 1977 through 1983 (date are from the EPRI Survey). Additions to direct heat uses in 1979 through 1981 are in Exhibit 7. A Table (not numbered) at the back of the report "Historical Development of Geothermal Power ..." shows world installed geothermal capacity by nation at decadal intervals from 1950 to 1980, and the first year of power production for each country. (DJE 2005)

  7. GEOTHERMAL EFFLUENT SAMPLING WORKSHOP

    EPA Science Inventory

    This report outlines the major recommendations resulting from a workshop to identify gaps in existing geothermal effluent sampling methodologies, define needed research to fill those gaps, and recommend strategies to lead to a standardized sampling methodology.

  8. Geothermal Energy: Current abstracts

    SciTech Connect

    Ringe, A.C.

    1988-02-01

    This bulletin announces the current worldwide information available on the technologies required for economic recovery of geothermal energy and its use as direct heat or for electric power production. (ACR)

  9. Geothermal Energy Retrofit

    SciTech Connect

    Bachman, Gary

    2015-07-28

    The Cleary University Geothermal Energy Retrofit project involved: 1. A thermal conductivity test; 2. Assessment of alternative horizontal and vertical ground heat exchanger options; 3. System design; 4. Asphalt was stripped from adjacent parking areas and a vertical geothermal ground heat exchanger system installed; 5. the ground heat exchanger was connected to building; 6. a system including 18 heat pumps, control systems, a manifold and pumps, piping for fluid transfer and ductwork for conditioned air were installed throughout the building.

  10. Geothermal reservoir simulation

    NASA Technical Reports Server (NTRS)

    Mercer, J. W., Jr.; Faust, C.; Pinder, G. F.

    1974-01-01

    The prediction of long-term geothermal reservoir performance and the environmental impact of exploiting this resource are two important problems associated with the utilization of geothermal energy for power production. Our research effort addresses these problems through numerical simulation. Computer codes based on the solution of partial-differential equations using finite-element techniques are being prepared to simulate multiphase energy transport, energy transport in fractured porous reservoirs, well bore phenomena, and subsidence.

  11. Geothermal Frontier: Penetrate a boundary between hydrothermal convection and heat conduction zones to create 'Beyond Brittle Geothermal Reservoir'

    NASA Astrophysics Data System (ADS)

    Tsuchiya, N.; Asanuma, H.; Sakaguchi, K.; Okamoto, A.; Hirano, N.; Watanabe, N.; Kizaki, A.

    2013-12-01

    EGS has been highlightened as a most promising method of geothermal development recently because of applicability to sites which have been considered to be unsuitable for geothermal development. Meanwhile, some critical problems have been experimentally identified, such as low recovery of injected water, difficulties to establish universal design/development methodology, and occurrence of large induced seismicity. Future geothermal target is supercritical and superheated geothermal fluids in and around ductile rock bodies under high temperatures. Ductile regime which is estimated beyond brittle zone is target region for future geothermal development due to high enthalpy fluids and relatively weak water-rock interaction. It is very difficult to determine exact depth of Brittle-Ductile boundary due to strong dependence of temperature (geotherm) and strain rate, however, ductile zone is considered to be developed above 400C and below 3 km in geothermal fields in Tohoku District. Hydrothermal experiments associated with additional advanced technology will be conducting to understand ';Beyond brittle World' and to develop deeper and hotter geothermal reservoir. We propose a new concept of the engineered geothermal development where reservoirs are created in ductile basement, expecting the following advantages: (a)simpler design and control the reservoir, (b)nearly full recovery of injected water, (c)sustainable production, (d)cost reduction by development of relatively shallower ductile zone in compression tectonic zones, (e)large quantity of energy extraction from widely distributed ductile zones, (f)establishment of universal and conceptual design/development methodology, and (g) suppression of felt earthquakes from/around the reservoirs. In ductile regime, Mesh-like fracture cloud has great potential for heat extraction between injection and production wells in spite of single and simple mega-fracture. Based on field observation and high performance hydrothermal

  12. Geothermal induced seismicity program plan

    SciTech Connect

    Not Available

    1981-03-01

    A plan for a National Geothermal Induced Seismicity Program has been prepared in consultation with a panel of experts from industry, academia, and government. The program calls for baseline seismic monitoring in regions of known future geothermal development, continued seismic monitoring and characterization of earthquakes in zones of geothermal fluid production and injection, modeling of the earthquake-inducing mechanism, and in situ measurement of stresses in the geothermal development. The Geothermal Induced Seismicity Program (GISP) will have as its objectives the evaluation of the seismic hazard, if any, associated with geothermal resource exploitation and the devising of a technology which, when properly utilized, will control or mitigate such hazards.

  13. Geothermal Field Developments in Japan

    SciTech Connect

    Hirakawa, Seiichi

    1983-12-15

    The present situation of the geothermal field developments in Japan is such that eight geothermal power stations are being operated, while there are sill many geothermal areas to be explored. Up to this day, the target of geothermal exploration has mainly been the areas by surface geological survey and the existing geothermal reservoirs are located not deeper than 1,500m depth. Recent geothermal energy development shows a trend from the study on vapor dominated of liquid dominated hydrothermal resources in shallow zones to that on hydrothermal resources in deeper zones. Exploration wells of 3,000m depth class have been drilled in Japan.

  14. In-line process instrumentation for geothermal power plants

    SciTech Connect

    Shannon, D.W.; Robertus, R.J.; Sullivan, R.G.; Kindle, C.H.; Pierce, D.D.

    1985-05-01

    The economics of geothermal power depend on satisfactory plant reliability of continuous operation. Plant problems and extended downtime due to corrosion failures, scale buildup, or injection well plugging have affected many past geothermal projects. If in-line instrumentation can be developed to alert plant operators to correctable problems, then the cost and reliability of geothermal power will be improved. PNL has completed a problem of development of in-line corrosion and chemical instrumentation for binary cycle plants, and this technology has been used to set up a monitoring program at the Heber Binary Demonstration Power Plant. The current emphasis has shifted to development of particle meters for use on injection lines and CO/sub 2/ and pH probes for use in control of calcite scaling. Plans have been outlined to develop and demonstrate flash plant instrumentation for corrosion monitoring, scaling, steam purity, and injection line particle counting. 2 refs., 17 figs., 1 tab.

  15. The National Geothermal Collaborative, EERE-Geothermal Program, Final Report

    SciTech Connect

    Jody Erikson

    2006-05-26

    Summary of the work conducted by the National Geothermal Collaborative (a consensus organization) to identify impediments to geothermal development and catalyze events and dialogues among stakeholders to over those impediments.

  16. Effects of irrigation on crops and soils with Raft River geothermal water

    SciTech Connect

    Stanley, N.E.; Schmitt, R.C.

    1980-01-01

    The Raft River Irrigation Experiment investigated the suitability of using energy-expended geothermal water for irrigation of selected field-grown crops. Crop and soil behavior on plots sprinkled or surface irrigated with geothermal water was compared to crop and soil behavior on plots receiving water from shallow irrigation wells and the Raft River. In addition, selected crops were produced, using both geothermal irrigation water and special management techniques. Crops irrigated with geothermal water exhibited growth rates, yields, and nutritional values similar to comparison crops. Cereal grains and surface-irrigated forage crops did not exhibit elevated fluoride levels or accumulations of heavy metals. However, forage crops sprinkled with geothermal water did accumulate fluorides, and leaching experiments indicate that new soils receiving geothermal water may experience increased salinity, exchangeable sodium, and decreased permeability. Soil productivity may be maintained by leaching irrigations.

  17. Measuring trauma and stressful events in childhood and adolescence among patients with first-episode psychosis: initial factor structure, reliability, and validity of the Trauma Experiences Checklist.

    PubMed

    Cristofaro, Sarah L; Cleary, Sean D; Ramsay Wan, Claire; Broussard, Beth; Chapman, Colby; Haggard, Patrick J; Jananeh, Sara; Myers, Neely L; Compton, Michael T

    2013-12-15

    Past trauma and stressful events, especially in childhood and adolescence, are common among individuals with serious mental illnesses like schizophrenia. Traumatic experiences are thought to be a socio-environmental risk factor not only for poorer outcomes, but also potentially for the onset of these disorders. Because improved measurement tools are needed, we developed and studied, among 205 first-episode psychosis patients, the factor structure, internal consistency reliability, and initial validity of the Trauma Experiences Checklist (TEC), our measure of trauma and stressful events during childhood/adolescence. We assessed validity of subscales using correlations with Childhood Trauma Questionnaire-Short Form, Parental Harsh Discipline, Violence Exposure, and TEC-Informant Version scores. Exploratory factor analysis resulted in two internally consistent subscales (Cronbach's α=0.79 and 0.80, respectively), interpersonal abuse and family stress, and violence, death, and legal involvement. Scores from the former subscale were substantially associated with CTQ-SF physical, emotional, and sexual abuse (r=0.42-0.57, all p<0.001) and Violence Exposure (r=0.49, p<0.001). On the other hand, violence, death, and legal involvement scores were most highly correlated with Violence Exposure (r=0.49, p<0.001), and not with most CTQ-SF subscales. The TEC is a potentially useful tool in assessing diverse traumatic life events across various social contexts during childhood and adolescence. PMID:23850437

  18. Why geothermal energy? Geothermal utilization in the Philippines

    SciTech Connect

    Gazo, F.M.

    1997-12-31

    This paper discusses the advantages of choosing geothermal energy as a resource option in the Philippine energy program. The government mandates the full-scale development of geothermal energy resources to meet increased power demand brought by rapid industrialization and economic growth, and to reduce fossil fuel importation. It also aims to realize these additional geothermal capacities by tapping private sector investments in the exploration, development, exploitation, construction, operation and management of various geothermal areas in the country.

  19. Reliability physics

    NASA Technical Reports Server (NTRS)

    Cuddihy, E. F.; Ross, R. G., Jr.

    1984-01-01

    Speakers whose topics relate to the reliability physics of solar arrays are listed and their topics briefly reviewed. Nine reports are reviewed ranging in subjects from studies of photothermal degradation in encapsulants and polymerizable ultraviolet stabilizers to interface bonding stability to electrochemical degradation of photovoltaic modules.

  20. Honey Lake hybrid geothermal wood residue power project

    SciTech Connect

    Toland, J.

    1981-05-01

    The Honey Lake Hybrid Geothermal Wood Residue Power Project with a planned output of 50 MW is undergoing feasibility studies funded by GeoProducts Corporation, Department of Water Resources, State of California, US Department of Energy and the Forest Service, USDA. The outlook is optimistic. It is reliably estimated that the required volume of woody biomass can be made available without environmental degradation.

  1. The status and future of geothermal power

    SciTech Connect

    Kutscher, Charles F.

    2000-08-01

    Geothermal electricity production in the United States began in 1960. Today there are over 20 plants in the western United States providing a total of about 2,200 MW of clean and reliable electricity. Currently identified resources could provide over 20,000 MW of power in the U.S., and undiscovered resources might provide 5 times that amount. In the 1990s industry growth slowed due to the loss of market incentives and competition from natural gas. However, increased interest in clean energy sources, ongoing technological improvements, and renewed opportunities abroad hold promise for a resurgence in the industry. This review paper covers the status of the technology, the issues faced, and the latest research. While the focus is on geothermal in the U.S., a brief description of the large international market is included.

  2. Geothermal energy: 1992 program overview

    SciTech Connect

    Not Available

    1993-04-01

    Geothermal energy is described in general terms with drawings illustrating the technology. A map of known and potential geothermal resources in the US is included. The 1992 program activities are described briefly. (MHR)

  3. Geothermal resources of Utah, 1980

    SciTech Connect

    Not Available

    1980-01-01

    This map shows heat flow, Known Geothermal Resources Areas, thermal springs and wells, and areas of low-temperature geothermal waters. Also shown are Indian reservations, military reservation, national or state forests, and parks, wildlife refuges, wilderness areas, etc. (MHR)

  4. The Geothermal Field Camp: Capacity building for geothermal energy systems in Indonesia

    NASA Astrophysics Data System (ADS)

    Moeck, I.; Sule, R.; Saptadji, N. M.; Deon, F.; Herdianita, N. R.; Jolie, E.; Suryantini, N.; Erbas, K.

    2012-04-01

    of the collected data with statistical techniques allowed a reliable interpretation and application of the related software. The course starts with a lecture day reviewing on geothermal exploration, introduction into structural geology, geochemistry and applied volcanology (1st day) and continues with practical work in the Tangkuban Perahu volcano field and surrounding area (2nd - 5th days, from morning until late afternoon). The collected field data are processed and analyzed daily after field work. On the last day, each group of participants gives a presentation related to their field and laboratory investigations and to evidence the lessons learned. In particular, the participants learn practical work in field and laboratory, and theoretical data analysis. Sampling and analysis of self-collected data are fundamental for any interpretation and assessment of reservoir potential. The success of the first Geothermal Field Camp 2011 speaks for a continuation and extension of the training program in 2012 and the following years. Future activity will integrate more collaboration partners and will cover a larger diversity of educational topics and geological-geothermal setting.

  5. South Dakota Geothermal Energy Handbook

    SciTech Connect

    Not Available

    1980-06-01

    The sources of geothermal fluids in South Dakota are described and some of the problems that exist in utilization and materials selection are detailed. Methods of heat extraction and the environmental concerns that accompany geothermal fluid development are briefly described. Governmental rules, regulations and legislation are explained. The time and steps necessary to bring about the development of the geothermal resources are explained in detail. Some of the federal incentives that encourage the use of geothermal energy are summarized.

  6. Accelerating Geothermal Research (Fact Sheet)

    SciTech Connect

    Not Available

    2014-05-01

    Geothermal research at the National Renewable Energy Laboratory (NREL) is advancing geothermal technologies to increase renewable power production. Continuous and not dependent on weather, the geothermal resource has the potential to jump to more than 500 gigawatts in electricity production, which is equivalent to roughly half of the current U.S. capacity. Enhanced geothermal systems have a broad regional distribution in the United States, allowing the potential for development in many locations across the country.

  7. Near-surface groundwater responses to injection of geothermal wastes

    SciTech Connect

    Arnold, S.C.

    1984-06-01

    Experiences with injecting geothermal fluids have identified technical problems associated with geothermal waste disposal. This report assesses the feasibility of injection as an alternative for geothermal wastewater disposal and analyzes hydrologic controls governing the upward migration of injected fluids. Injection experiences at several geothermal developments are presented, including: Raft River, Salton Sea, East Mesa, Otake and Hatchobaru in Japan, and Ahuachapan in El Salvador. Hydrogeologic and design/operational factors affecting the success of an injection program are identified. Hydrogeologic factors include subsidence, near-surface effects of injected fluids, and seismicity. Design/operational factors include hydrodynamic breakthrough, condition of the injection system and reservoir maintenance. Existing and potential effects of production/injection on these factors are assessed.

  8. Combining geothermal energy capture with geologic carbon dioxide sequestration

    NASA Astrophysics Data System (ADS)

    Randolph, Jimmy B.; Saar, Martin O.

    2011-05-01

    Geothermal energy offers clean, renewable, reliable electric power with no need for grid-scale energy storage, yet its use has been constrained to the few locations worldwide with naturally high geothermal heat resources and groundwater availability. We present a novel approach with the potential to permit expansion of geothermal energy utilization: heat extraction from naturally porous, permeable formations with CO2 as the injected subsurface working fluid. Fluid-mechanical simulations reveal that the significantly higher mobility of CO2, compared to water, at the temperature/pressure conditions of interest makes CO2 an attractive heat exchange fluid. We show numerically that, compared to conventional water-based and engineered geothermal systems, the proposed approach provides up to factors of 2.9 and 5.0, respectively, higher geothermal heat energy extraction rates. Consequently, more regions worldwide could be economically used for geothermal electricity production. Furthermore, as the injected CO2 is eventually geologically sequestered, such power plants would have negative carbon footprints.

  9. Geothermal pipeline - progress and development update, geothermal progress monitor

    SciTech Connect

    1996-08-01

    This document is a progress and development update and geothermal progress monitor prepared by the Geo-Heat Center at the Oregon Institute of Technology in Klamath Falls, Oregon. Several upcoming meetings in the field of geothermal energy and resource development are announced. Proposed and past geothermal activities within the Glass Mountain Known Geothermal Resource Area are also discussed. As of this date, there has been limited geothermal exploration in this area, however, two projects located in the near vicinity have been proposed within the last two years.

  10. Geothermal: Energy for development - The World Bank and geothermal development

    SciTech Connect

    Bertelsmeier, W.

    1986-01-01

    The World Bank views geothermal energy as one of a variety of natural resources which can be developed to supply the energy needs of a country. Since the World Bank Group finances projects in developing countries. This paper discusses geothermal energy only in that context. Geothermal power is generated in nine developing countries today, which represent nearly 40% of worldwide geothermal generating capacity. The World Bank has helped finance geothermal investments in six of these countries-the Phillippines, Mexico, El Salvador, Nicaragua, Indonesia and Kenya.

  11. Geothermal energy and the utility market -- the opportunities and challenges for expanding geothermal energy in a competitive supply market: Proceedings

    SciTech Connect

    Not Available

    1992-01-01

    Each year the Geothermal Division of the US Department of Energy conducts an in-depth review of its entire geothermal R D program. The conference serves several purposes: a status report on current R D activities, an assessment of progress and problems, a review of management issues, and a technology transfer opportunity between DOE and the US geothermal city. This year's conference, Program Review X, was held in San Francisco on March 24--26, 1992. The theme of the review, Geothermal Energy and the Utility Market -- The Opportunities and Challenges for Expanding Geothermal Energy in a Competitive Supply Market,'' focused on the needs of the electric utility sector. Geothermal energy, with its power capacity potential of 10 GWe by the year 2010, can provide reliable, enviromentally clean electricity which can help offset the projected increase in demand. Program Review X consisted of seven sessions including an opening session with presentations by Mr. Vikram Budhraja, Vice President of System Planning and Operations, Southern California Edison Company, and Mr. Richard Jaros, President and Chief Operating Officer, California Energy Company. The six technical sessions included presentations by the relevant field researchers covering DOE-sponsored R D in hydrothermal, hot dry rock, and geopressured energy. Individual projects are processed separately for the data bases.

  12. Geothermal energy program summary: Volume 1: Overview Fiscal Year 1988

    SciTech Connect

    Not Available

    1989-02-01

    Geothermal energy is a here-and-now technology for use with dry steam resources and high-quality hydrothermal liquids. These resources are supplying about 6% of all electricity used in California. However, the competitiveness of power generation using lower quality hydrothermal fluids, geopressured brines, hot dry rock, and magma still depends on the technology improvements sought by the DOE Geothermal Energy R and D Program. The successful outcome of the R and D initiatives will serve to benefit the US public in a number of ways. First, if a substantial portion of our geothermal resources can be used economically, they will add a very large source of secure, indigenous energy to the nation's energy supply. In addition, geothermal plants can be brought on line quickly in case of a national energy emergency. Geothermal energy is also a highly reliable resource, with very high plant availability. For example, new dry steam plants at The Geysers are operable over 99% of the time, and the small flash plant in Hawaii, only the second in the United States, has an availability factor of 98%. Geothermal plants also offer a viable baseload alternative to fossil and nuclear plants -- they are on line 24 hours a day, unaffected by diurnal or seasonal variations. The hydrothermal power plants with modern emission control technology have proved to have minimal environmental impact. The results to date with geopressured and hot dry rock resources suggest that they, too, can be operated so as to reduce environmental effects to well within the limits of acceptability. Preliminary studies on magma are also encouraging. In summary, the character and potential of geothermal energy, together with the accomplishments of DOE's Geothermal R and D Program, ensure that this huge energy resource will play a major role in future US energy markets. 7 figs.

  13. Geothermal energy program summary: Volume 1: Overview Fiscal Year 1988

    NASA Astrophysics Data System (ADS)

    1989-02-01

    Geothermal energy is a here-and-now technology for use with dry steam resources and high-quality hydrothermal liquids. These resources are supplying about 6 percent of all electricity used in California. However, the competitiveness of power generation using lower quality hydrothermal fluids, geopressured brines, hot dry rock, and magma still depends on the technology improvements sought by the DOE Geothermal Energy R and D Program. The successful outcome of the R and D initiatives will serve to benefit the U.S. public in a number of ways. First, if a substantial portion of our geothermal resources can be used economically, they will add a very large source of secure, indigenous energy to the nation's energy supply. In addition, geothermal plants can be brought on line quickly in case of a national energy emergency. Geothermal energy is also a highly reliable resource, with very high plant availability. For example, new dry steam plants at The Geysers are operable over 99 percent of the time, and the small flash plant in Hawaii, only the second in the United States, has an availability factor of 98 percent. Geothermal plants also offer a viable baseload alternative to fossil and nuclear plants -- they are on line 24 hours a day, unaffected by diurnal or seasonal variations. The hydrothermal power plants with modern emission control technology have proved to have minimal environmental impact. The results to date with geopressured and hot dry rock resources suggest that they, too, can be operated so as to reduce environmental effects to well within the limits of acceptability. Preliminary studies on magma are also encouraging. In summary, the character and potential of geothermal energy, together with the accomplishments of DOE's Geothermal R and D Program, ensure that this huge energy resource will play a major role in future U.S. energy markets.

  14. Reliable solar cookers

    SciTech Connect

    Magney, G.K.

    1992-12-31

    The author describes the activities of SERVE, a Christian relief and development agency, to introduce solar ovens to the Afghan refugees in Pakistan. It has provided 5,000 solar cookers since 1984. The experience has demonstrated the potential of the technology and the need for a durable and reliable product. Common complaints about the cookers are discussed and the ideal cooker is described.

  15. Geothermal hydrogen sulfide removal

    SciTech Connect

    Urban, P.

    1981-04-01

    UOP Sulfox technology successfully removed 500 ppM hydrogen sulfide from simulated mixed phase geothermal waters. The Sulfox process involves air oxidation of hydrogen sulfide using a fixed catalyst bed. The catalyst activity remained stable throughout the life of the program. The product stream composition was selected by controlling pH; low pH favored elemental sulfur, while high pH favored water soluble sulfate and thiosulfate. Operation with liquid water present assured full catalytic activity. Dissolved salts reduced catalyst activity somewhat. Application of Sulfox technology to geothermal waters resulted in a straightforward process. There were no requirements for auxiliary processes such as a chemical plant. Application of the process to various types of geothermal waters is discussed and plans for a field test pilot plant and a schedule for commercialization are outlined.

  16. Geothermal Plant Capacity Factors

    SciTech Connect

    Greg Mines; Jay Nathwani; Christopher Richard; Hillary Hanson; Rachel Wood

    2015-01-01

    The capacity factors recently provided by the Energy Information Administration (EIA) indicated this plant performance metric had declined for geothermal power plants since 2008. Though capacity factor is a term commonly used by geothermal stakeholders to express the ability of a plant to produce power, it is a term frequently misunderstood and in some instances incorrectly used. In this paper we discuss how this capacity factor is defined and utilized by the EIA, including discussion on the information that the EIA requests from operations in their 923 and 860 forms that are submitted both monthly and annually by geothermal operators. A discussion is also provided regarding the entities utilizing the information in the EIA reports, and how those entities can misinterpret the data being supplied by the operators. The intent of the paper is to inform the facility operators as the importance of the accuracy of the data that they provide, and the implications of not providing the correct information.

  17. Geothermal energy program summary

    SciTech Connect

    Not Available

    1990-01-01

    The Geothermal Technology Division (GTD) of the US Department of Energy (DOE) is charged with the lead federal role in the research and development (R D) of technologies that will assist industry in economically exploiting the nation's vast geothermal resources. The GTD R D Program represents a comprehensive, balanced approach to establishing all forms of geothermal energy as significant contributors to the nation's energy supply. It is structured both to maintain momentum in the growth of the existing hydrothermal industry and to develop long-term options offering the greatest promise for practical applications. This volume, Volume 2, contains a detailed compilation of each GTD-funded R D activity performed by national laboratories or under contract to industrial, academic, and nonprofit research institutions.

  18. Geothermal reservoir engineering research

    NASA Technical Reports Server (NTRS)

    Ramey, H. J., Jr.; Kruger, P.; Brigham, W. E.; London, A. L.

    1974-01-01

    The Stanford University research program on the study of stimulation and reservoir engineering of geothermal resources commenced as an interdisciplinary program in September, 1972. The broad objectives of this program have been: (1) the development of experimental and computational data to evaluate the optimum performance of fracture-stimulated geothermal reservoirs; (2) the development of a geothermal reservoir model to evaluate important thermophysical, hydrodynamic, and chemical parameters based on fluid-energy-volume balances as part of standard reservoir engineering practice; and (3) the construction of a laboratory model of an explosion-produced chimney to obtain experimental data on the processes of in-place boiling, moving flash fronts, and two-phase flow in porous and fractured hydrothermal reservoirs.

  19. Geothermal steam condensate reinjection

    NASA Technical Reports Server (NTRS)

    Chasteen, A. J.

    1974-01-01

    Geothermal electric generating plants which use condensing turbines and generate and excess of condensed steam which must be disposed of are discussed. At the Geysers, California, the largest geothermal development in the world, this steam condensate has been reinjected into the steam reservoir since 1968. A total of 3,150,000,000 gallons of steam condensate has been reinjected since that time with no noticeable effect on the adjacent producing wells. Currently, 3,700,000 gallons/day from 412 MW of installed capacity are being injected into 5 wells. Reinjection has also proven to be a satisfactory method of disposing of geothermal condensate a Imperial Valley, California, and at the Valles Caldera, New Mexico.

  20. Advanced geothermal technologies

    SciTech Connect

    Whetten, J.T.; Murphy, H.D.; Hanold, R.J.; Myers, C.W.; Dunn, J.C.

    1988-01-01

    Research and development in advanced technologies for geothermal energy production continue to increase the energy production options for the Nation. The high-risk investment over the past few years by the US Department of Energy in geopressured, hot dry rock, and magma energy resources is producing new means to lower production costs and to take advantage of these resources. The Nation has far larger and more regionally extensive geothermal resources than heretofore realized. At the end of a short 30-day closed-loop flow test, the manmade hot dry rock reservoir at Fenton Hill, New Mexico, was producing 10 MW thermal - and still climbing - proving the technical feasibility of this new technology. The scientific feasibility of magma energy extraction has been demonstrated, and new field tests to evaluate this technology are planned. Analysis and field tests confirm the viability of geopressured-geothermal energy and the prospect that many dry-hole or depleted petroleum wells can be turned into producing geopressured-geothermal wells. Technological advances achieved through hot dry rock, magma, geopressured, and other geothermal research are making these resources and conventional hydrothermal resources more competitive. Noteworthy among these technological advances are techniques in computer simulation of geothermal reservoirs, new means for well stimulation, new high-temperature logging tools and packers, new hard-rock penetration techniques, and new methods for mapping fracture flow paths across large underground areas in reservoirs. In addition, many of these same technological advances can be applied by the petroleum industry to help lower production costs in domestic oil and gas fields. 5 refs., 4 figs.

  1. Network reliability

    NASA Technical Reports Server (NTRS)

    Johnson, Marjory J.

    1985-01-01

    Network control (or network management) functions are essential for efficient and reliable operation of a network. Some control functions are currently included as part of the Open System Interconnection model. For local area networks, it is widely recognized that there is a need for additional control functions, including fault isolation functions, monitoring functions, and configuration functions. These functions can be implemented in either a central or distributed manner. The Fiber Distributed Data Interface Medium Access Control and Station Management protocols provide an example of distributed implementation. Relative information is presented here in outline form.

  2. Software reliability studies

    NASA Technical Reports Server (NTRS)

    Wilson, Larry W.

    1989-01-01

    The longterm goal of this research is to identify or create a model for use in analyzing the reliability of flight control software. The immediate tasks addressed are the creation of data useful to the study of software reliability and production of results pertinent to software reliability through the analysis of existing reliability models and data. The completed data creation portion of this research consists of a Generic Checkout System (GCS) design document created in cooperation with NASA and Research Triangle Institute (RTI) experimenters. This will lead to design and code reviews with the resulting product being one of the versions used in the Terminal Descent Experiment being conducted by the Systems Validations Methods Branch (SVMB) of NASA/Langley. An appended paper details an investigation of the Jelinski-Moranda and Geometric models for software reliability. The models were given data from a process that they have correctly simulated and asked to make predictions about the reliability of that process. It was found that either model will usually fail to make good predictions. These problems were attributed to randomness in the data and replication of data was recommended.

  3. Geothermal well stimulation

    SciTech Connect

    Sinclair, A.R.; Pittard, F.J.; Hanold, R.J.

    1980-01-01

    All available data on proppants and fluids were examined to determine areas in technology that need development for 300 to 500/sup 0/F (150/sup 0/ to 265/sup 0/C) hydrothermal wells. While fluid properties have been examined well into the 450/sup 0/F range, proppants have not been previously tested at elevated temperatures except in a few instances. The latest test data at geothermal temperatures is presented and some possible proppants and fluid systems that can be used are shown. Also discussed are alternative stimulation techniques for geothermal wells.

  4. California's geothermal resource potential

    NASA Technical Reports Server (NTRS)

    Leibowitz, L. P.

    1978-01-01

    According to a U.S. Geological Survey estimate, recoverable hydrothermal energy in California may amount to 19,000 MW of electric power for a 30-year period. At present, a geothermal installation in the Geysers region of the state provides 502 MWe of capacity; an additional 1500 MWe of electric generating capacity is scheduled to be in operation in geothermal fields by 1985. In addition to hydrothermal energy sources, hot-igneous and conduction-dominated resources are under investigation for possible development. Land-use conflicts, environmental concerns and lack of risk capital may limit this development.

  5. Geothermal Energy; (USA)

    SciTech Connect

    Raridon, M.H.; Hicks, S.C.

    1991-01-01

    Geothermal Energy (GET) announces on a bimonthly basis the current worldwide information available on the technologies required for economic recovery of geothermal energy and its use as direct heat or for electric power production. This publication contains the abstracts of DOE reports, journal article, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database (EDB) during the past two months. Also included are US information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency's Energy Technology Data Exchange or government-to-government agreements.

  6. Geothermal hazards - Mercury emission

    NASA Technical Reports Server (NTRS)

    Siegel, S. M.; Siegel, B. Z.

    1975-01-01

    Enthusiasm for intensified geothermal exploration may induce many participants to overlook a long-term potential toxicity hazard possibly associated with the tapping of magmatic steam. The association of high atmospheric Hg levels with geothermal activity has been established both in Hawaii and Iceland, and it has been shown that mercury can be introduced into the atmosphere from fumaroles, hot springs, and magmatic sources. These arguments, extended to thallium, selenium, and other hazardous elements, underscore the need for environmental monitoring in conjunction with the delivery of magmatic steam to the surface.

  7. Silica recovery and control in Hawaiian geothermal fluids

    SciTech Connect

    Thomas, D.M.

    1992-06-01

    A series of experiments was performed to investigate methods of controlling silica in waste geothermal brines produced at the HGP-A Generator Facility. Laboratory testing has shown that the rate of polymerization of silica in the geothermal fluids is highly pH dependent. At brine pH values in excess of 8.5 the suspension of silica polymers flocculated and rapidly precipitated a gelatinous silica mass. Optimum flocculation and precipitation rates were achieved at pH values in the range of 10.5 to 11.5. The addition of transition metal salts to the geothermal fluids similarly increased the rate of polymerization as well as the degree of precipitation of the silica polymer from suspension. A series of experiments performed on the recovered silica solids demonstrated that methanol extraction of the water in the gels followed by critical point drying yielded surface areas in excess of 300 M{sup 2}/g and that treatment of the dried solids with 2 N HCl removed most of the adsorbed impurities in the recovered product. A series of experiments tested the response of the waste brines to mixing with steam condensate and non-condensable gases.The results demonstrated that the addition of condensate and NCG greatly increased the stability of the silica in the geothermal brines. They also indicated that the process could reduce the potential for plugging of reinjection wells receiving waste geothermal fluids from commercial geothermal facilities in Hawaii. Conceptual designs were proposed to apply the gas re-combination approach to the disposal of geothermal waste fluids having a range of chemical compositions. Finally, these designs were applied to the geothermal fluid compositions found at Cerro Prieto, Ahuachapan, and Salton Sea.

  8. Silica recovery and control in Hawaiian geothermal fluids. Final report

    SciTech Connect

    Thomas, D.M.

    1992-06-01

    A series of experiments was performed to investigate methods of controlling silica in waste geothermal brines produced at the HGP-A Generator Facility. Laboratory testing has shown that the rate of polymerization of silica in the geothermal fluids is highly pH dependent. At brine pH values in excess of 8.5 the suspension of silica polymers flocculated and rapidly precipitated a gelatinous silica mass. Optimum flocculation and precipitation rates were achieved at pH values in the range of 10.5 to 11.5. The addition of transition metal salts to the geothermal fluids similarly increased the rate of polymerization as well as the degree of precipitation of the silica polymer from suspension. A series of experiments performed on the recovered silica solids demonstrated that methanol extraction of the water in the gels followed by critical point drying yielded surface areas in excess of 300 M{sup 2}/g and that treatment of the dried solids with 2 N HCl removed most of the adsorbed impurities in the recovered product. A series of experiments tested the response of the waste brines to mixing with steam condensate and non-condensable gases.The results demonstrated that the addition of condensate and NCG greatly increased the stability of the silica in the geothermal brines. They also indicated that the process could reduce the potential for plugging of reinjection wells receiving waste geothermal fluids from commercial geothermal facilities in Hawaii. Conceptual designs were proposed to apply the gas re-combination approach to the disposal of geothermal waste fluids having a range of chemical compositions. Finally, these designs were applied to the geothermal fluid compositions found at Cerro Prieto, Ahuachapan, and Salton Sea.

  9. Human Resources in Geothermal Development

    SciTech Connect

    Fridleifsson, I.B.

    1995-01-01

    Some 80 countries are potentially interested in geothermal energy development, and about 50 have quantifiable geothermal utilization at present. Electricity is produced from geothermal in 21 countries (total 38 TWh/a) and direct application is recorded in 35 countries (34 TWh/a). Geothermal electricity production is equally common in industrialized and developing countries, but plays a more important role in the developing countries. Apart from China, direct use is mainly in the industrialized countries and Central and East Europe. There is a surplus of trained geothermal manpower in many industrialized countries. Most of the developing countries as well as Central and East Europe countries still lack trained manpower. The Philippines (PNOC) have demonstrated how a nation can build up a strong geothermal workforce in an exemplary way. Data from Iceland shows how the geothermal manpower needs of a country gradually change from the exploration and field development to monitoring and operations.

  10. Multidisciplinary research of geothermal modeling

    NASA Astrophysics Data System (ADS)

    -Ing. Ulvi Arslan, Univ., ., Dr. _., Prof.; Heiko Huber, Dipl.-Ing.

    2010-05-01

    KEYWORDS Geothermal sciences, geothermics, research, theory and application, numerical calculation, geothermal modeling, Technical University Darmstadt, Ministry of Economics and Technology (BMWi) INTRODUCTION In times of global warming renewable, green energies are getting more and more important. The development of application of geothermal energy as a part of renewable energies in Germany is a multidisciplinary process of fast growing research and improvements. Geothermal energy is the energy, which is stored below earth's surface. The word geothermal derives from the Greek words geo (earth) and thermos (heat), so geothermal is a synonym to earth heat. Geothermal energy is one of the auspicious renewable energies. In average the temperature increases 3°C every 100 m of depth, which is termed as geothermal gradient. Therefore 99 percent of our planet is hotter than 1.000°C, while 99 percent of that last percent is even hotter than 100°C. Already in a depth of about 1 kilometer temperatures of 35 - 40°C can be achieved. While other renewable energies arise less or more from the sun, geothermal energy sources its heat from the earth's interior, which is caused mostly by radioactive decay of persistent isotopes. This means a possibility of a base-loadable form of energy supply. Especially efficient is the use of deep geothermal energy of high-enthalpie reservoirs, which means a high energy potential in low depths. In Germany no high-enthalpie reservoirs are given. To use the given low-enthalpie potential and to generate geothermal power efficiently inventions and improvements need to be performed. An important part of geothermal progresses is performed by universities with multidisciplinary research of geothermal modeling. Especially in deep geothermal systems numerical calculations are essential for a correct dimensioning of the geothermal system. Therefore German universities and state aided organizations are developing numerical programs for a detailed use of

  11. 2008 Geothermal Technologies Market Report

    SciTech Connect

    Cross, J.; Freeman, J.

    2009-07-01

    This report describes market-wide trends for the geothermal industry throughout 2008 and the beginning of 2009. It begins with an overview of the U.S. DOE's Geothermal Technology Program's (GTP's) involvement with the geothermal industry and recent investment trends for electric generation technologies. The report next describes the current state of geothermal power generation and activity within the United States, costs associated with development, financing trends, an analysis of the levelized cost of energy (LCOE), and a look at the current policy environment. The report also highlights trends regarding direct use of geothermal energy, including geothermal heat pumps (GHPs). The final sections of the report focus on international perspectives, employment and economic benefits from geothermal energy development, and potential incentives in pending national legislation.

  12. Geothermal development plan: northern Arizona counties

    SciTech Connect

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

    1982-08-01

    The Northern Counties Area Development Plan evaluated the regional market potential for utilizing geothermal energy. This study identified five potential geothermal resource areas, four of which have low temperature (<90{sup 0}C, 194{sup 0}F) potential and one possible igneous system. The average population growth rate in the Northern Counties is expected to be five percent per year over the next 40 years, with Mohave and Yavapai Counties growing the fastest. Rapid growth is anticipated in all major employment sectors, including trade, service, manufacturing, mining and utilities. A regional energy use analysis is included, containing information on current energy use patterns for all user classes. Water supplies are expected to be adequate for expected growth generally, though Yavapai and Gila Counties will experience water deficiencies. A preliminary district heating analysis is included for the towns of Alpine and Springerville. Both communities are believed located on geothermal resource sites. The study also contains a section identifying potential geothermal resource users in northern Arizona.

  13. Advanced Electric Submersible Pump Design Tool for Geothermal Applications

    SciTech Connect

    Xuele Qi; Norman Turnquist; Farshad Ghasripoor

    2012-05-31

    Electrical Submersible Pumps (ESPs) present higher efficiency, larger production rate, and can be operated in deeper wells than the other geothermal artificial lifting systems. Enhanced Geothermal Systems (EGS) applications recommend lifting 300 C geothermal water at 80kg/s flow rate in a maximum 10-5/8-inch diameter wellbore to improve the cost-effectiveness. In this paper, an advanced ESP design tool comprising a 1D theoretical model and a 3D CFD analysis has been developed to design ESPs for geothermal applications. Design of Experiments was also performed to optimize the geometry and performance. The designed mixed-flow type centrifugal impeller and diffuser exhibit high efficiency and head rise under simulated EGS conditions. The design tool has been validated by comparing the prediction to experimental data of an existing ESP product.

  14. Shallow open-loop geothermal systems: simulation of heat transfer in groundwater and experimental tests for improving parameterization

    NASA Astrophysics Data System (ADS)

    Fossoul, F.; Orban, P.; Dassargues, A.; Hydrogeology; Environmental Geology

    2011-12-01

    Innovative and efficient strategies for energy use become a priority, especially in civil engineering. Geothermal open-loop systems (geothermal wells) are not so developed in Belgium contrary to close-loop systems. This is generally due to the lack of relevant dimensioning and impact study that must be foreseen during the planning phases of the building. However, as shallow groundwater is widely available, geothermal wells potential is significant. Using both experimental and numerical tools, our aim is to develop a rigorous methodology to design heating and cooling shallow geothermal wells (pumping/reinjection), with a detailed hydrogeological characterization coupled to feasibility, environmental impact assessment, dimensioning, and system sustainability. Concerning numerical modeling, Groundwater flow and heat transfer is computed using different codes (HydroGeoSphere, MT3DMS and SHEMAT) for a comparative sensitivity analysis on a typical case. Coupling and temperature non linearities of hydro-thermal parameters values are checked accurately. As shown previously, small temperature variations (temperatures ranging from 12 to 25 °C) allow to use conventional solute transport codes for modeling heat transfer in groundwater taking benefits of the similarities between solute transport and heat transfer equations. When numerical codes are used as dimensioning tools for long-term simulations, reliable values for hydro-thermal properties of the aquifer are essential. As very few experimental values are available in the literature, field experiments are needed to determine more accurately the local values in different geological/hydrogeological conditions. Apart from thermal response tests (TRT) usually performed for designing a close-loop system within a borehole considered in static groundwater conditions, there is no standard procedure for geothermal wells systems. In an open-loop system, groundwater movement induced by the pumping is responsible for a major heat

  15. Geothermal research and development program of the US Atomic Energy Commission

    NASA Technical Reports Server (NTRS)

    Werner, L. B.

    1974-01-01

    Within the overall federal geothermal program, the Atomic Energy Commission has chosen to concentrate on development of resource utilization and advanced research and technology as the areas most suitable to the expertise of its staff and that of the National Laboratories. The Commission's work in geothermal energy is coordinated with that of other agencies by the National Science Foundation, which has been assigned lead agency by the Office of Management and Budget. The objective of the Commission's program, consistent with the goals of the total federal program is to facilitate, through technological advancement and pilot plant operations, achievement of substantial commercial production of electrical power and utilization of geothermal heat by the year 1985. This will hopefully be accomplished by providing, in conjunction with industry, credible information on the economic operation and technological reliability of geothermal power and use of geothermal heat.

  16. OIT geothermal system improvements

    SciTech Connect

    Lienau, P.J.

    1996-08-01

    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.

  17. Geothermal energy conversion facility

    SciTech Connect

    Kutscher, C.F.

    1997-12-31

    With the termination of favorable electricity generation pricing policies, the geothermal industry is exploring ways to improve the efficiency of existing plants and make them more cost-competitive with natural gas. The Geothermal Energy Conversion Facility (GECF) at NREL will allow researchers to study various means for increasing the thermodynamic efficiency of binary cycle geothermal plants. This work has received considerable support from the US geothermal industry and will be done in collaboration with industry members and utilities. The GECF is being constructed on NREL property at the top of South Table Mountain in Golden, Colorado. As shown in Figure 1, it consists of an electrically heated hot water loop that provides heating to a heater/vaporizer in which the working fluid vaporizes at supercritical or subcritical pressures as high as 700 psia. Both an air-cooled and water-cooled condenser will be available for condensing the working fluid. In order to minimize construction costs, available equipment from the similar INEL Heat Cycle Research Facility is being utilized.

  18. Reinjection into geothermal reservoirs

    SciTech Connect

    Bodvarsson, G.S.; Stefansson, V.

    1987-08-01

    Reinjection of geothermal wastewater is practiced as a means of disposal and for reservoir pressure support. Various aspects of reinjection are discussed, both in terms of theoretical studies as well as specific field examples. The discussion focuses on the major effects of reinjection, including pressure maintenance and chemical and thermal effects. (ACR)

  19. Geothermal industry assessment

    SciTech Connect

    Not Available

    1980-07-01

    An assessment of the geothermal industry is presented, focusing on industry structure, corporate activities and strategies, and detailed analysis of the technological, economic, financial, and institutional issues important to government policy formulation. The study is based principally on confidential interviews with executives of 75 companies active in the field. (MHR)

  20. Energy 101: Geothermal Energy

    SciTech Connect

    2014-05-27

    See how we can generate clean, renewable energy from hot water sources deep beneath the Earth's surface. The video highlights the basic principles at work in geothermal energy production, and illustrates three different ways the Earth's heat can be converted into electricity.

  1. Energy 101: Geothermal Energy

    ScienceCinema

    None

    2014-06-23

    See how we can generate clean, renewable energy from hot water sources deep beneath the Earth's surface. The video highlights the basic principles at work in geothermal energy production, and illustrates three different ways the Earth's heat can be converted into electricity.

  2. Geothermal Systems for School.

    ERIC Educational Resources Information Center

    Dinse, David H.

    1998-01-01

    Describes an award-winning school heating and cooling system in which two energy-efficient technologies, variable-flow pumping and geothermal heat pumps, were combined. The basic system schematic and annual energy use and cost savings statistics are provided. (GR)

  3. Geothermal Grows Up

    ERIC Educational Resources Information Center

    Johnson, William C.; Kraemer, Steven; Ormond, Paul

    2011-01-01

    Self-declared energy and carbon reduction goals on the part of progressive colleges and universities have driven ground source geothermal space heating and cooling systems into rapid evolution, as part of long-term climate action planning efforts. The period of single-building or single-well solutions is quickly being eclipsed by highly engineered…

  4. Simulation of geothermal subsidence

    SciTech Connect

    Miller, I.; Dershowitz, W.; Jones, K.; Myer, L.; Roman, K.; Schauer, M.

    1980-03-01

    The results of an assessment of existing mathematical models for subsidence simulation and prediction are summarized. The following subjects are discussed: the prediction process, physical processes of geothermal subsidence, computational models for reservoir flow, computational models for deformation, proficiency assessment, and real and idealized case studies. (MHR)

  5. Reliability Centered Maintenance - Methodologies

    NASA Technical Reports Server (NTRS)

    Kammerer, Catherine C.

    2009-01-01

    Journal article about Reliability Centered Maintenance (RCM) methodologies used by United Space Alliance, LLC (USA) in support of the Space Shuttle Program at Kennedy Space Center. The USA Reliability Centered Maintenance program differs from traditional RCM programs because various methodologies are utilized to take advantage of their respective strengths for each application. Based on operational experience, USA has customized the traditional RCM methodology into a streamlined lean logic path and has implemented the use of statistical tools to drive the process. USA RCM has integrated many of the L6S tools into both RCM methodologies. The tools utilized in the Measure, Analyze, and Improve phases of a Lean Six Sigma project lend themselves to application in the RCM process. All USA RCM methodologies meet the requirements defined in SAE JA 1011, Evaluation Criteria for Reliability-Centered Maintenance (RCM) Processes. The proposed article explores these methodologies.

  6. National Geothermal Data System (NGDS)

    DOE Data Explorer

    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.

  7. Geothermal Energy Development in China

    SciTech Connect

    Kuide, Xin; Qilong, Yang

    1983-12-15

    China's geothermal resources are mainly of low - medium temperature. More than 30 geothermal areas have been or are being explorated. According to the geology, economy and technology of geothermal energy development main efforts are concentrated in some places with better conditions and can be exploited effectively in the near future, such as low temperature geothermal fields in Beijing and Tianjin, Yangbajain and Dengchong high temperature geothermal fields respectively in Tibet and Ynnan province. In Beijing and Tianjin the geothermal water is used for space heating, bathing, medical treatment, greenhouse, raising tropical fish, industry and so on. In Beijing now more than 200 thousand sq. m. of indoor floor is being heated with geothermal water and about 50 thousand persons per day use it to take bath. In future, the low temperature geothermal water utilization in these big citites would flourish. In 1970 the first experimental geothermal power plant using the flashing method was built in Dengwu, Guangdong province. In 1977 one MW experimental wet steam power plant was built in Yangbajain, Tibet, a 6 MW power plant in 1981, and another 3 MW generator is expected to complete in 1985. This paper is intended to summarize some important results of exploration, particularly in the geothermal reservoir engineering.

  8. Statistical modeling of software reliability

    NASA Technical Reports Server (NTRS)

    Miller, Douglas R.

    1992-01-01

    This working paper discusses the statistical simulation part of a controlled software development experiment being conducted under the direction of the System Validation Methods Branch, Information Systems Division, NASA Langley Research Center. The experiment uses guidance and control software (GCS) aboard a fictitious planetary landing spacecraft: real-time control software operating on a transient mission. Software execution is simulated to study the statistical aspects of reliability and other failure characteristics of the software during development, testing, and random usage. Quantification of software reliability is a major goal. Various reliability concepts are discussed. Experiments are described for performing simulations and collecting appropriate simulated software performance and failure data. This data is then used to make statistical inferences about the quality of the software development and verification processes as well as inferences about the reliability of software versions and reliability growth under random testing and debugging.

  9. Temperature distribution in the Cerro Prieto geothermal field

    SciTech Connect

    Castillo B, F.; Bermejo M, F.J.; Domiguez A, B.; Esquer P, C.A.; Navarro O, F.J.

    1981-01-01

    A series of temperature and pressure logs and flow rate measurements was compiled for each of the geothermal wells drilled to different reservoir depths between October 1979 and December 1980. Based on the valuable information obtained, a series of graphs showing the thermal characteristics of the reservoir were prepared. These graphs clearly show the temperature distribution resulting from the movement of fluids from the deep regions toward the higher zones of the reservoir, thus establishing more reliable parameters for locating new wells with better production zones. Updated information based on data from new deep wells drilled in the geothermal field is presented here. This new information does not differ much from earlier estimates and theories. However, the influence of faulting and fracturing on the hydrothermal recharge of the geothermal reservoir is seen more clearly.

  10. Agriculture, greenhouse, wetland and other beneficial uses of geothermal fluids and heat

    SciTech Connect

    Schmitt, R.C.

    1981-04-05

    The status for related beneficial uses including agriculture, greenhousing, and geothermal wetlands is presented. Data published for the geothermal fluids found in areas of China have been examined and compared with the geothermal fluids used in the agriculture evaluations in the United States. This comparison indicates that the geothermal fluids found in parts of China are similar to those used in the US agriculture experiments. Greenhousing is addressed largely from the standpoint of hardware systems and technology being employed or being proposed in the United States.

  11. Thirteenth workshop on geothermal reservoir engineering: Proceedings

    SciTech Connect

    Ramey, H.J. Jr.; Kruger, P.; Horne, R.N.; Brigham, W.E.; Miller, F.G.; Cook, J.W.

    1988-01-21

    PREFACE The Thirteenth Workshop on Geothermal Reservoir Engineering was held at Stanford University on January 19-21, 1988. Although 1987 continued to be difficult for the domestic geothermal industry, world-wide activities continued to expand. Two invited presentations on mature geothermal systems were a keynote of the meeting. Malcolm Grant presented a detailed review of Wairakei, New Zealand and highlighted plans for new development. G. Neri summarized experience on flow rate decline and well test analysis in Larderello, Italy. Attendance continued to be high with 128 registered participants. Eight foreign countries were represented: England, France, Iceland, Italy, New Zealand, Japan, Mexico and The Philippines. A discussion of future workshops produced a strong recommendation that the Stanford Workshop program continue for the future. There were forty-one technical presentations at the Workshop. All of these are published as papers in this Proceedings volume. Four technical papers not presented at the Workshop are also published. In addition to these forty five technical presentations or papers, the introductory address was given by Henry J. Ramey, Jr. from the Stanford Geothermal Program. The Workshop Banquet speaker was Gustavo Calderon from the Inter-American Development Bank. We thank him for sharing with the Workshop participants a description of the Bank???s operations in Costa Rica developing alternative energy resources, specifically Geothermal, to improve the country???s economic basis. His talk appears as a paper in the back of this volume. The chairmen of the technical sessions made an important contribution to the workshop. Other than Stanford faculty members they included: J. Combs, G. T. Cole, J. Counsil, A. Drenick, H. Dykstra, K. Goyal, P. Muffler, K. Pruess, and S. K. Sanyal. The Workshop was organized by the Stanford Geothermal Program faculty, staff and students. We would like to thank Marilyn King, Pat Oto, Terri Ramey, Bronwyn Jones

  12. Geothermal energy in Nevada: development and utilization

    SciTech Connect

    Not Available

    1982-01-01

    The nature of geothermal resources in Nevada and resource applications are discussed. The social and economic advantages of using geothermal energy are outlined. Federal and state programs established to foster the development of geothermal energy are discussed. (MHR)

  13. Photovoltaic module reliability workshop

    NASA Astrophysics Data System (ADS)

    Mrig, L.

    The paper and presentations compiled in this volume form the Proceedings of the fourth in a series of Workshops sponsored by Solar Energy Research Institute (SERI/DOE) under the general theme of photovoltaic module reliability during the period 1986 to 1990. The reliability photovoltaic (PV) modules/systems is exceedingly important along with the initial cost and efficiency of modules if the PV technology has to make a major impact in the power generation market, and for it to compete with the conventional electricity producing technologies. The reliability of photovoltaic modules has progressed significantly in the last few years as evidenced by warrantees available on commercial modules of as long as 12 years. However, there is still need for substantial research and testing required to improve module field reliability to levels of 30 years or more. Several small groups of researchers are involved in this research, development, and monitoring activity around the world. In the U.S., PV manufacturers, DOE laboratories, electric utilities and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in this field were brought together under SERI/DOE sponsorship to exchange the technical knowledge and field experience as related to current information in this important field. The papers presented here reflect this effort.

  14. Photovoltaic module reliability workshop

    SciTech Connect

    Mrig, L.

    1990-01-01

    The paper and presentations compiled in this volume form the Proceedings of the fourth in a series of Workshops sponsored by Solar Energy Research Institute (SERI/DOE) under the general theme of photovoltaic module reliability during the period 1986--1990. The reliability Photo Voltaic (PV) modules/systems is exceedingly important along with the initial cost and efficiency of modules if the PV technology has to make a major impact in the power generation market, and for it to compete with the conventional electricity producing technologies. The reliability of photovoltaic modules has progressed significantly in the last few years as evidenced by warranties available on commercial modules of as long as 12 years. However, there is still need for substantial research and testing required to improve module field reliability to levels of 30 years or more. Several small groups of researchers are involved in this research, development, and monitoring activity around the world. In the US, PV manufacturers, DOE laboratories, electric utilities and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in this field were brought together under SERI/DOE sponsorship to exchange the technical knowledge and field experience as related to current information in this important field. The papers presented here reflect this effort.

  15. Geothermal systems on the island of Bali, Indonesia

    NASA Astrophysics Data System (ADS)

    Purnomo, Budi Joko; Pichler, Thomas

    2015-10-01

    This paper presents an overview of the geothermal systems on the island of Bali, Indonesia. Physicochemical data of hot springs and shallow geothermal wells were collected from four geothermal locations: Penebel, Batur, Banjar and Banyuwedang. The concentrations for the three main anions varied significantly indicating a different geothermal history. The values for Cl- ranged from 0.1 to 1000 mg/L, for HCO3- from 20 to 2200 mg/L and for SO42 - from 0.1 to 500 mg/L. Although the island of Bali is underlain by carbonate rocks, a carbonate host rock for the geothermal reservoirs could not be confirmed, because the (Ca2 + + Mg2 +)/HCO3- molar ratios were approximately 0.4, well below 1.0 and the K/Mg ratios were approaching those of a calc-alkaline rock reservoir. The HCO3- of the thermal waters correlated with Ca2 +, Mg2 +, Sr2 + and K+ indicating water-rock interaction in the presence of carbonic acid. Phase separation was inferred for the Bedugul and Banjar geothermal systems, because of relatively high B/Cl ratios. Boron isotopes were determined for selected samples with values ranging from δ11B of 1.3 to 22.5‰ (NBS 951). The heavy δ11B of + 22.5‰ together with a low B/Cl ratio indicated seawater input in the Banyuwedang geothermal system. The hydrogen and oxygen isotopic composition of the thermal water plotted along the global meteoric water line (GMWL) and close to the mean annual value for precipitation in Jakarta indicating a meteoric origin of the geothermal water. Comparison of the Si, Na/K, Na/K/Ca and Na/Li geothermometers with actual reservoir temperature measurements and physicochemical considerations led to the conclusion that the Na/Li thermometer provided most reliable results for the determination of geothermal reservoir temperatures on Bali. Using this thermometer, the following reservoir temperatures were calculated: (1) Penebel (Bedugul) from 235 to 254 °C, (2) Batur 240 °C and (3) Banjar 255 °C. Due to seawater input this thermometer

  16. Geothermal development plan: Yuma county

    SciTech Connect

    White, D.H.

    1981-01-01

    One hot spring and 33 wells drilled in the county discharge water at temperatures sufficient for direct-use geothermal applications such as process heat and space heating and cooling. Currently, one industry within the county has been identified which may be able to use geothermal energy for its process heat requirements. Also, a computer simulation model was used to predict geothermal energy on line as a function of time under both private and city-owned utility development of the resource.

  17. Chemical logging of geothermal wells

    DOEpatents

    Allen, C.A.; McAtee, R.E.

    The presence of geothermal aquifers can be detected while drilling in geothermal formations by maintaining a chemical log of the ratio of the concentrations of calcium to carbonate and bicarbonate ions in the return drilling fluid. A continuous increase in the ratio of the concentrations of calcium to carbonate and bicarbonate ions is indicative of the existence of a warm or hot geothermal aquifer at some increased depth.

  18. Chemical logging of geothermal wells

    DOEpatents

    Allen, Charles A.; McAtee, Richard E.

    1981-01-01

    The presence of geothermal aquifers can be detected while drilling in geothermal formations by maintaining a chemical log of the ratio of the concentrations of calcium to carbonate and bicarbonate ions in the return drilling fluid. A continuous increase in the ratio of the concentrations of calcium to carbonate and bicarbonate ions is indicative of the existence of a warm or hot geothermal aquifer at some increased depth.

  19. A fourth generation reliability predictor

    NASA Technical Reports Server (NTRS)

    Bavuso, Salvatore J.; Martensen, Anna L.

    1988-01-01

    A reliability/availability predictor computer program has been developed and is currently being beta-tested by over 30 US companies. The computer program is called the Hybrid Automated Reliability Predictor (HARP). HARP was developed to fill an important gap in reliability assessment capabilities. This gap was manifested through the use of its third-generation cousin, the Computer-Aided Reliability Estimation (CARE III) program, over a six-year development period and an additional three-year period during which CARE III has been in the public domain. The accumulated experience of the over 30 establishments now using CARE III was used in the development of the HARP program.

  20. Spacecraft transmitter reliability

    NASA Technical Reports Server (NTRS)

    1980-01-01

    A workshop on spacecraft transmitter reliability was held at the NASA Lewis Research Center on September 25 and 26, 1979, to discuss present knowledge and to plan future research areas. Since formal papers were not submitted, this synopsis was derived from audio tapes of the workshop. The following subjects were covered: users' experience with space transmitters; cathodes; power supplies and interfaces; and specifications and quality assurance. A panel discussion ended the workshop.

  1. Reliability and testing

    NASA Technical Reports Server (NTRS)

    Auer, Werner

    1996-01-01

    Reliability and its interdependence with testing are important topics for development and manufacturing of successful products. This generally accepted fact is not only a technical statement, but must be also seen in the light of 'Human Factors.' While the background for this paper is the experience gained with electromechanical/electronic space products, including control and system considerations, it is believed that the content could be also of interest for other fields.

  2. Validation of a Geothermal Simulator

    SciTech Connect

    Shook, G.M.; Faulder, D.D.

    1991-10-01

    A geothermal simulator, TETRAD, is validated against the Stanford Geothermal Problem Set. The governing equations, formulation, and solution technique employed by TETRAD are first outlined. Each problem in the Stanford Problem Set is then discussed in detail, and results from the simulations are presented. The results obtained using TETRAD are compared against several other geothermal simulators. Favorable comparison between results indicates that TETRAD is capable of solving the highly non-linear equations describing the flow of mass and energy in porous media. This validation exercise allows for the use of TETRAD in studying geothermal problems with a high degree of confidence.

  3. The Philippines geothermal success story

    NASA Astrophysics Data System (ADS)

    Birsic, R. J.

    1980-09-01

    Geothermal electrical plants currently in operation in the Philippines are presented. Following a brief review of the geographical and energy situation of the nation, attention is given to the first 55,000-kW unit of the Tiwi Geothermal Electric Plant, which commenced operation in January 1979, the portable 3,000-kE Leyte Geothermal Pilot Plant, which commenced operation in July, 1977 as the first geothermal power plant in the country, the Makiling-Banahaw (Mak-Ban) Geothermal Power Plant, the first 55,000-kW unit of which began operation in May, 1979 and the second 55,000-kW unit of the Tiwi plant, which came into service in June, 1979, thus making the Philippines the fourth largest producer of geothermal electricity in the world. Factors favoring the use of geothermal plants in developing nations are pointed out, including low capital costs, no foreign exchange costs for fuel, small units, and little environmental impact, and the start-up of two more plants, the second 55,000-kW unit at Mak-Ban in September 1979 and the third Tiwi unit in January 1980, are noted. It is predicted that in 1981, when the Philippines is expected to become the largest user of geothermal energy from hot-water fields, it will have a total capacity of 552 MW from the Mak-Ban, Tiwi and Leyte sites. Further areas with geothermal potential are also pointed out.

  4. Direct application of geothermal energy

    SciTech Connect

    Reistad, G.M.

    1980-01-01

    An overall treatment of direct geothermal applications is presented with an emphasis on the above-ground engineering. The types of geothermal resources and their general extent in the US are described. The potential market that may be served with geothermal energy is considered briefly. The evaluation considerations, special design aspects, and application approaches for geothermal energy use in each of the applications are considered. The present applications in the US are summarized and a bibliography of recent studies and applications is provided. (MHR)

  5. Economic Impacts of Geothermal Development in Malheur County, Oregon.

    SciTech Connect

    Sifford, Alex; Beale, Kasi

    1993-01-01

    This study provides local economic impact estimates for a 100 megawatt (MW) geothermal power project in Oregon. The hypothetical project would be in Malheur County, shown in Figure 1. Bonneville Power Administration commissioned this study to quantify such impacts as part of regional confirmation work recommended by the Northwest Power Planning Council and its advisors. Malheur County was chosen as it has both identified resources and industry interest. Local economic impacts include direct, indirect, and induced changes in the local economy. Direct economic impacts result from the costs of plant development, construction, and operation. Indirect impacts result from household and local government purchases. Induced impacts result from continued responding as goods and services to support the households and local governments are purchased. Employment impacts of geothermal development follow a pattern similar to the economic impacts. Public service impacts include costs such as education, fire protection, roads, waste disposal, and water supply. The project assumption discussion notes experiences at other geothermal areas. The background section compares geothermal with conventional power plants. Power plant fuel distinguishes geothermal from other power sources. Other aspects of development are similar to small scale conventional thermal sources. The process of geothermal development is then explained. Development consists of well drilling, gathering system construction, power plant construction, plant operation and maintenance, and wellfield maintenance.

  6. Improving geothermal power plants with a binary cycle

    NASA Astrophysics Data System (ADS)

    Tomarov, G. V.; Shipkov, A. A.; Sorokina, E. V.

    2015-12-01

    The recent development of binary geothermal technology is analyzed. General trends in the introduction of low-temperature geothermal sources are summarized. The use of single-phase low-temperature geothermal fluids in binary power plants proves possible and expedient. The benefits of power plants with a binary cycle in comparison with traditional systems are shown. The selection of the working fluid is considered, and the influence of the fluid's physicochemical properties on the design of the binary power plant is discussed. The design of binary power plants is based on the chemical composition and energy potential of the geothermal fluids and on the landscape and climatic conditions at the intended location. Experience in developing a prototype 2.5 MW Russian binary power unit at Pauzhetka geothermal power plant (Kamchatka) is outlined. Most binary systems are designed individually for a specific location. Means of improving the technology and equipment at binary geothermal power plants are identified. One option is the development of modular systems based on several binary systems that employ the heat from the working fluid at different temperatures.

  7. Geothermal Energy Market in Southern California Past, Present and Future

    SciTech Connect

    Budhraja, Vikram S.

    1992-03-24

    I'm pleased to be here as your keynote speaker from the utility industry. Today is fitting to discuss the role of an alternative/renewable energy resource such as geothermal. Three years ago today, the Exxon Valdez oil tanker spilled 11 million gallons of oil into Prince William Sound, Alaska. This ecological catastrophe was another of those periodic jolts that underscores the importance of lessening our nation's dependence on oil and increasing the use of cost-effective, environmentally benign alternative/renewable energy sources. Alternative/renewables have come a long way since the first oil crisis in 1973. Today, they provide 9 percent of electric power used in the United States. That's nearly double the figure of just two years ago. And since 1985, one-third of a new capacity has come from geothermal, solar, wind and biomass facilities. Nevertheless, geothermal supplies only about three-tenths of a percent of the country's electric power, or roughly 2,800 megawatts (MW). And most of that is in California. In fact, geothermal is California's second-largest source of renewable energy, supplying more than 5 percent of the power generated in the state. Today, I'd like to discuss the outlook for the geothermal industry, framing it within Southern California Edison's experience with geothermal and other alternative/renewable energy sources.

  8. NATIONAL GEOTHERMAL DATA SYSTEM (NGDS) GEOTHERMAL DATA DOMAIN: ASSESSMENT OF GEOTHERMAL COMMUNITY DATA NEEDS

    SciTech Connect

    Anderson, Arlene; Blackwell, David; Chickering, Cathy; Boyd, Toni; Horne, Roland; MacKenzie, Matthew; Moore, Joseph; Nickull, Duane; Richard, Stephen; Shevenell, Lisa A.

    2013-01-01

    To satisfy the critical need for geothermal data to ad- vance geothermal energy as a viable renewable ener- gy contender, the U.S. Department of Energy is in- vesting in the development of the National Geother- mal Data System (NGDS). This paper outlines efforts among geothermal data providers nationwide to sup- ply cutting edge geo-informatics. NGDS geothermal data acquisition, delivery, and methodology are dis- cussed. In particular, this paper addresses the various types of data required to effectively assess geother- mal energy potential and why simple links to existing data are insufficient. To create a platform for ready access by all geothermal stakeholders, the NGDS in- cludes a work plan that addresses data assets and re- sources of interest to users, a survey of data provid- ers, data content models, and how data will be ex- changed and promoted, as well as lessons learned within the geothermal community.

  9. Hawaii's geothermal program

    SciTech Connect

    Zorpette, G.

    1992-02-01

    This paper reports that in a forest on the island of Hawaii, legal and regulatory activity has postponed the start-up of a small new power plant and imperilled the design and construction of several facilities like it. The same old story Hardly. The power plants at stake are not nuclear or coal- or even oil-fired, but geothermal, widely considered one of the more environmentally benign ways of generating electricity. In a further twist, the opposition is coming not only from the usual citizens; and environmental groups, but also from worshippers of a native good and, it has been alleged, growers of marijuana, a lucrative local crop. The clash occurs just as geothermal power sources have finally proven commercially viable, experts say, adding that technological advances and industry trends in the United States and elsewhere seem to factor great expansion in its use.

  10. Making geothermal power competitive

    NASA Astrophysics Data System (ADS)

    Fassbender, L. L.; Bloomster, C. H.

    The near-term supply curve for the electrical applications of geothermal energy is presented, and the impacts of technological improvements are illustrated. The curve is derived using the subsurface temperature, reservoir thickness, and heat content estimates made by the U.S. Geological Survey for the identified high-temperature and intermediate-temperature hydrothermal resources of the western U.S. Each step in the curve is composed of one or more geothermal resources identified by the USGS. Both high- and intermediate-temperature resources were included up to an arbitrary cost ceiling of 100 mills/kWh. Curves are drawn to show the impacts of combinations of technological advances expected to be achieved by 1982 and 1985. It is shown that most of the identified hydrothermal resources could become competitive with conventional energy sources for electrical power production by 1985.

  11. Amedee geothermal power plant

    SciTech Connect

    Hodgson, S.F.

    1988-12-01

    In September 1988, the power plant began generating electricity in Northern California, near Honey Lake. The plant generates 2 megawatts, net, of electricity in the winter, and from 20 to 30% less in the summer, depending on the temperature. Geothermal fluids from two wells are used to operate the plant, and surface discharge is used to dispose of the spent fluids. This is possible because the geothermal fluids have a very low salinity and a composition the same as area hot spring waters. The binary power plant has a Standard Offer No. 4 contract for 5 megawatts with pacific Gas and Electric Company. Sometime in the near future, they will expand the project to add another 3 megawatts of electrical generation.

  12. Fracturing operations in a dry geothermal reservoir

    SciTech Connect

    Rowley, J.C.; Pettitt, R.A.; Hendron, R.H.; Sinclair, A.R.; Nicholson, R.W.

    1983-01-01

    Fracturing and completing deep wells in hot, nonporous crystalline basement rock challenges conventional equipment use, procedures, and techniques common in oil and gas and normal geothermal completions. Fracturing operations at the Fenton Hill, New Mexico, Hot Dry Rock (HDR) Geothermal Test Site initiated unique developments necessary to solve problems caused by an extremely harsh down-hole environment. Hydraulic fracturing experiments to connect the 2 wells have used openhole packers, hydraulic jet notching of the borehole wall, cemented-in isolation liners, and casing packers. Problems were encountered with hole drag, high fracture gradients, H/sub 2/S in vent back fluids, stress corrosion cracking of tubulars, and the complex nature of 3-dimensional fracture growth that requires large volumes of injected water. 20 references.

  13. Photovoltaic performance and reliability workshop

    SciTech Connect

    Mrig, L.

    1993-12-01

    This workshop was the sixth in a series of workshops sponsored by NREL/DOE under the general subject of photovoltaic testing and reliability during the period 1986--1993. PV performance and PV reliability are at least as important as PV cost, if not more. In the US, PV manufacturers, DOE laboratories, electric utilities, and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in the field were brought together to exchange the technical knowledge and field experience as related to current information in this evolving field of PV reliability. The papers presented here reflect this effort since the last workshop held in September, 1992. The topics covered include: cell and module characterization, module and system testing, durability and reliability, system field experience, and standards and codes.

  14. Photovoltaic performance and reliability workshop

    NASA Astrophysics Data System (ADS)

    Mrig, L.

    1993-12-01

    This workshop was the sixth in a series of workshops sponsored by NREL/DOE under the general subject of photovoltaic testing and reliability during the period 1986-1993. PV performance and PV reliability are at least as important as PV cost, if not more. In the U.S., PV manufacturers, DOE laboratories, electric utilities, and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in the field were brought together to exchange the technical knowledge and field experience as related to current information in this evolving field of PV reliability. The papers presented here reflect this effort since the last workshop held in September, 1992. The topics covered include: cell and module characterization, module and system testing, durability and reliability, system field experience, and standards and codes.

  15. Colorado Geothermal Commercialization Program

    SciTech Connect

    Healy, F.C.

    1980-04-01

    Chaffee County, located in central Colorado, has immense potential for geothermal development. This report has been prepared to assist residents and developers in and outside the area to develop the hydrothermal resources of the county. Data has been collected and interpreted from numerous sources in order to introduce a general description of the area, estimate energy requirements, describe the resources and postulate a development plan. Electric power generation and direct heat application potential for the region are described.

  16. Geothermal resources of Montana

    SciTech Connect

    Metesh, J.

    1994-06-01

    The Montana Bureau of Mines and Geology has updated its inventory of low and moderate temperature resources for the state and has assisted the Oregon Institute of Technology - GeoHeat Center and the University of Utah Research Institute in prioritizing and collocating important geothermal resource areas. The database compiled for this assessment contains information on location, flow, water chemistry, and estimated reservoir temperatures for 267 geothermal well and springs in Montana. For this assessment, the minimum temperature for low-temperature resource is defined as 10{degree} C above the mean annual air temperature at the surface. The maximum temperature for a moderate-temperature resource is defined as greater than 50{degree} C. Approximately 12% of the wells and springs in the database have temperatures above 50{degree} C, 17% are between 30{degree} and 50{degree} C, 29% are between 20{degree} and 30{degree}C, and 42% are between 10{degree} and 20{degree} C. Low and moderate temperature wells and springs can be found in nearly all areas of Montana, but most are in the western third of the state. Information sources for the current database include the MBMG Ground Water Information Center, the USGS statewide database, the USGS GEOTHERM database, and new information collected as part of this program. Five areas of Montana were identified for consideration in future investigations of geothermal development. The areas identified are those near Bozeman, Ennis, Butte, Boulder, and Camas Prairie. These areas were chosen based on the potential of the resource and its proximity to population centers.

  17. Federal Interagency Geothermal Activities

    SciTech Connect

    Anderson, Arlene; Prencipe, Loretta; Todaro, Richard M.; Cuyler, David; Eide, Elizabeth

    2011-06-01

    This collaborative document describes the roles and responsibilities of key Federal agencies in the development of geothermal technologies including the U.S. Department of Energy (DOE); the U.S. Department of Agriculture (USDA), including the U.S. Forest Service; the U.S. Department of Interior (DOI), including the United States Geological Survey (USGS) and Bureau of Land Management (BLM); the Environmental Protection Agency (EPA); and the Department of Defense (DOD).

  18. GEOTHERMAL POWER GENERATION PLANT

    SciTech Connect

    Boyd, Tonya

    2013-12-01

    Oregon Institute of Technology (OIT) drilled a deep geothermal well on campus (to 5,300 feet deep) which produced 196oF resource as part of the 2008 OIT Congressionally Directed Project. OIT will construct a geothermal power plant (estimated at 1.75 MWe gross output). The plant would provide 50 to 75 percent of the electricity demand on campus. Technical support for construction and operations will be provided by OIT’s Geo-Heat Center. The power plant will be housed adjacent to the existing heat exchange building on the south east corner of campus near the existing geothermal production wells used for heating campus. Cooling water will be supplied from the nearby cold water wells to a cooling tower or air cooling may be used, depending upon the type of plant selected. Using the flow obtained from the deep well, not only can energy be generated from the power plant, but the “waste” water will also be used to supplement space heating on campus. A pipeline will be construction from the well to the heat exchanger building, and then a discharge line will be construction around the east and north side of campus for anticipated use of the “waste” water by facilities in an adjacent sustainable energy park. An injection well will need to be drilled to handle the flow, as the campus existing injection wells are limited in capacity.

  19. UWC geothermal resource exploration

    SciTech Connect

    1996-04-01

    A program was developed to explore the strength of the geothermal and hot dry rock (HDR) resource at the Montezuma Hot Springs at the United World College (UWC). The purpose of the UWC {number_sign}1 well is to obtain hydrologic, geologic, and temperature information for ongoing geothermal evaluation of the Montezuma Hot Springs area. If sufficient fluids are encountered, the hole will be cased with a 4 1/2 inch production casing and re-permitted as a geothermal low-temperature well. If no fluid is encountered, the well will be abandoned per Oil Conservation Division regulation. The objectives of the exploration are to evaluate the resource potential to provide space heating for the entire campus of the United World College, determine the effect of a well on the Hot Springs outflow, accurately measure the UWC heating loads versus time, evaluate the potential to support local thermal industry development, assess the feasibility of HDR development, and create an educational program from the collection of data derived from the research effort.

  20. Geotherm: the U.S. geological survey geothermal information system

    USGS Publications Warehouse

    Bliss, J.D.; Rapport, A.

    1983-01-01

    GEOTHERM is a comprehensive system of public databases and software used to store, locate, and evaluate information on the geology, geochemistry, and hydrology of geothermal systems. Three main databases address the general characteristics of geothermal wells and fields, and the chemical properties of geothermal fluids; the last database is currently the most active. System tasks are divided into four areas: (1) data acquisition and entry, involving data entry via word processors and magnetic tape; (2) quality assurance, including the criteria and standards handbook and front-end data-screening programs; (3) operation, involving database backups and information extraction; and (4) user assistance, preparation of such items as application programs, and a quarterly newsletter. The principal task of GEOTHERM is to provide information and research support for the conduct of national geothermal-resource assessments. The principal users of GEOTHERM are those involved with the Geothermal Research Program of the U.S. Geological Survey. Information in the system is available to the public on request. ?? 1983.

  1. Geotherm: the U.S. geological survey geothermal information system

    NASA Astrophysics Data System (ADS)

    Bliss, J. D.; Rapport, A.

    GEOTHERM is a comprehensive system of public databases and software used to store, locate, and evaluate information on the geology, geochemistry, and hydrology of geothermal systems. Three main databases address the general characteristics of geothermal wells and fields, and the chemical properties of geothermal fluids; the last database is currently the most active. System tasks are divided into four areas: (1) data acquisition and entry, involving data entry via word processors and magnetic tape; (2) quality assurance, including the criteria and standards handbook and front-end data-screening programs; (3) operation, involving database backups and information extraction; and (4) user assistance, preparation of such items as application programs, and a quarterly newsletter. The principal task of GEOTHERM is to provide information and research support for the conduct of national geothermal-resource assessments. The principal users of GEOTHERM are those involved with the Geothermal Research Program of the U.S. Geological Survey. Information in the system is available to the public on request.

  2. Software reliability report

    NASA Technical Reports Server (NTRS)

    Wilson, Larry

    1991-01-01

    There are many software reliability models which try to predict future performance of software based on data generated by the debugging process. Unfortunately, the models appear to be unable to account for the random nature of the data. If the same code is debugged multiple times and one of the models is used to make predictions, intolerable variance is observed in the resulting reliability predictions. It is believed that data replication can remove this variance in lab type situations and that it is less than scientific to talk about validating a software reliability model without considering replication. It is also believed that data replication may prove to be cost effective in the real world, thus the research centered on verification of the need for replication and on methodologies for generating replicated data in a cost effective manner. The context of the debugging graph was pursued by simulation and experimentation. Simulation was done for the Basic model and the Log-Poisson model. Reasonable values of the parameters were assigned and used to generate simulated data which is then processed by the models in order to determine limitations on their accuracy. These experiments exploit the existing software and program specimens which are in AIR-LAB to measure the performance of reliability models.

  3. NON-DESTRUCTIVE TESTING METHODS FOR GEOTHERMAL PIPING.

    SciTech Connect

    BERNDT,M.L.

    2001-03-23

    Non-destructive testing is a key component of optimized plant inspection and maintenance programs. Risk based inspection, condition based maintenance and reliability centered maintenance systems all require detection, location and sizing of defects or flaws by non-destructive methods. Internal damage of geothermal piping by corrosion and erosion-corrosion is an ongoing problem requiring inspection and subsequent maintenance decisions to ensure safe and reliable performance. Conventional manual ultrasonic testing to determine remaining wall thickness has major limitations, particularly when damage is of a random and localized nature. Therefore, it is necessary to explore alternative non-destructive methods that offer potential benefits in terms of accurate quantification of size, shape and location of damage, probability of detection, ability to use on-line over long ranges, and economics. A review of non-destructive methods and their applicability to geothermal piping was performed. Based on this, ongoing research will concentrate on long range guided wave and dynamic methods.

  4. Evolution of high-temperature geothermal brine production pumps

    SciTech Connect

    Ellis, P.F. II )

    1989-01-01

    Geothermal resources with temperatures between 250{degrees} and 360{degrees}F (121{degrees} and 182{degrees}C) are prime candidates for binary-cycle power generation in the United States and abroad, and constitute about 80% of the known power-capable resources in the United States. Initially there were many technological obstacles to exploitation of these resources, with one of the greatest being the absence of reliable high-capacity downwell brine production pumps to supply the required amounts of brine from an economically small group of wells. Early experience revealed many problems with downwell pumps, resulting in a mean-time-to-failure (MTTF) in 1981 of less than 1000 hours for the best available technology. This paper reports how evolutionary advances in pump design and materials selection have resolved most of the early problems, producing third- generation pumps which have run as long as 20,000 hours. Pump life extension practices - greatly enhanced component and assembly quality control, increased care in pump installation, and continuous monitoring of pump performance with swift intervention at the first signs of distress - have essentially eliminated premature failure where implemented, leading to estimated near-term MTTFs of 8000 hours.

  5. The Future of Geothermal Energy

    SciTech Connect

    Kubik, Michelle

    2006-01-01

    A comprehensive assessment of enhanced, or engineered, geothermal systems was carried out by an 18-member panel assembled by the Massachusetts Institute of Technology (MIT) to evaluate the potential of geothermal energy becoming a major energy source for the United States.

  6. Silica extraction from geothermal water

    SciTech Connect

    Bourcier, William L; Bruton, Carol J

    2014-09-23

    A method of producing silica from geothermal fluid containing low concentration of the silica of less than 275 ppm includes the steps of treating the geothermal fluid containing the silica by reverse osmosis treatment thereby producing a concentrated fluid containing the silica, seasoning the concentrated fluid thereby producing a slurry having precipitated colloids containing the silica, and separating the silica from the slurry.

  7. Middlesex Community College Geothermal Project

    SciTech Connect

    Klein, Jessie; Spaziani, Gina

    2013-03-29

    The purpose of the project was to install a geothermal system in the trustees house on the Bedford campus of Middlesex Community College. In partnership with the environmental science faculty, learning activities for environmental science courses were developed to explain geothermal energy and more specifically the newly installed system to Middlesex students. A real-time monitoring system highlights the energy use and generation.

  8. Energy 101: Geothermal Heat Pumps

    SciTech Connect

    2011-01-01

    An energy-efficient heating and cooling alternative, the geothermal heat pump system moves heat from the ground to a building (or from a building to the ground) through a series of flexible pipe "loops" containing water. This edition of Energy 101 explores the benefits Geothermal and the science behind how it all comes together.

  9. Geothermal Energy: Tapping the Potential

    ERIC Educational Resources Information Center

    Johnson, Bill

    2008-01-01

    Ground source geothermal energy enables one to tap into the earth's stored renewable energy for heating and cooling facilities. Proper application of ground-source geothermal technology can have a dramatic impact on the efficiency and financial performance of building energy utilization (30%+). At the same time, using this alternative energy…

  10. Energy 101: Geothermal Heat Pumps

    ScienceCinema

    None

    2013-05-29

    An energy-efficient heating and cooling alternative, the geothermal heat pump system moves heat from the ground to a building (or from a building to the ground) through a series of flexible pipe "loops" containing water. This edition of Energy 101 explores the benefits Geothermal and the science behind how it all comes together.

  11. Geothermal Energy: Prospects and Problems

    ERIC Educational Resources Information Center

    Ritter, William W.

    1973-01-01

    An examination of geothermal energy as a means of increasing the United States power resources with minimal pollution problems. Developed and planned geothermal-electric power installations around the world, capacities, installation dates, etc., are reviewed. Environmental impact, problems, etc. are discussed. (LK)

  12. Empirical equation estimates geothermal gradients

    SciTech Connect

    Kutasov, I.M. )

    1995-01-02

    An empirical equation can estimate geothermal (natural) temperature profiles in new exploration areas. These gradients are useful for cement slurry and mud design and for improving electrical and temperature log interpretation. Downhole circulating temperature logs and surface outlet temperatures are used for predicting the geothermal gradients.

  13. Geothermal energy research and development

    SciTech Connect

    Fridleifsson, I.B. ); Freeston, D.H. . Geothermal Inst.)

    1994-04-01

    Today, electricity is generated from geothermal energy in 21 countries. The installed capacity is nearly 6300 MW-electric. Four developing countries (El Salvador 18%, Kenya 11%, Nicaragua 18% and Philippines 21%) produce over 10% of their total electricity from geothermal. Electric generation cost is commonly around 4 US cents/kWh. Direct utilization of geothermal water is known in about 40 countries, thereof 14 countries have each an installed capacity of over 100 MW-thermal. A worldwide survey shows that the total investments in geothermal energy between 1973 and 1992 amounted to approximately 22 billion US$. During the two decades, 30 countries invested each over 20 million US$, 12 countries over 200 million US$, and 5 countries over 1 billion US$. During the first decade, 1973--1982, public funding amounted to 4.6 billion US$ and private funding to 3 billion US$. During the second decade, 1983--1992, public funding amounted to 6.6 billion US$ and private funding to 7.7 billion US$. The relative economic viability of geothermal energy will improve significantly if and when a pollution tax is endorsed on power production using fossil fuels. Geothermal exploration and exploitation requires skills from many scientific and engineering disciplines. International geothermal training centers are operated in Iceland, Italy, Japan, Mexico, and New Zealand. The International Geothermal Association was founded in 1988 and has over 2,000 members in all parts of the world.

  14. Mushroom growing project at the Los Humeros, Mexico geothermal field

    SciTech Connect

    Rangel, M.E.R.

    1998-12-01

    There are several projects of direct (non-electrical) use of geothermal energy in Mexico. Personnel of the Comision Federal de Electricidad (CFE) have experience in various of these projects, like drying of timber and fruits, space heating, food processing, etc. Taking this in consideration, CFE built the Los Humeros mushroom plant using for heat source the geothermal steam from Well H-1. The main purpose of the project was to take advantage of residual geothermal energy in a food production operation and to develop the appropriate technology. In 1992, existing installations were renovated, preparing appropriate areas for pasteurization, inoculation and production. The mushroom Pleurotus ostreatus var. florida and columbinus was used. A year later, CFE proposed the construction of improved facilities for growing edible mushrooms. New materials and equipment, as well as different operation conditions, were proposed on the basis of the experience gained in the initial project. The construction and renovation activities were completed in 1994.

  15. Reliability and Confidence.

    ERIC Educational Resources Information Center

    Test Service Bulletin, 1952

    1952-01-01

    Some aspects of test reliability are discussed. Topics covered are: (1) how high should a reliability coefficient be?; (2) two factors affecting the interpretation of reliability coefficients--range of talent and interval between testings; (3) some common misconceptions--reliability of speed tests, part vs. total reliability, reliability for what…

  16. World Geothermal Congress WGC-2015

    NASA Astrophysics Data System (ADS)

    Tomarov, G. V.; Shipkov, A. A.

    2016-08-01

    This article discusses materials and results of the World Geothermal Congress that was held in Melbourne (Australia) from April 19 to April 25, 2015. Information on the extent and technological features of utilization of geothermal resources for heat supply and power production, as well as in other economic areas, is given. A stable growth in the capacity and number of geothermal power systems that is determined by ecological cleanliness, economic efficiency, and the highest (among renewable energy sources) indicators of installed capacity utilization is shown. It was noted that combined schemes of geothermal power plants (GPPs), such as turbine units of different type (binary units, units with one or two separation pressures, etc.), have become more frequently used to increase the efficiency of utilization of geothermal heat carrier. Actual data determining room heating systems with the total worldwide capacity of nearly 50000 MW thermal (MWt) as the most currently significant segment of consumption of geothermal waters are given. In addition, geothermal resources are also utilized in soil pumps, balneological and sports basins, greenhouse complexes, and other manufactures. It was noted that geological studies were carried out in more than 40 countries, with the development of methods of simulation of tanks for the existing and new geothermal fields. Trends of development and the role of geothermal power engineering in the energy supply of many countries are shown. It was shown that prospects for the development of geothermal power generation are significantly associated with utilization of low-temperature geothermal sources in binary power generating units, as well as with the increase in installed capacity of operating geothermal power plants (GPPs) without drilling additional wells, i.e., by using waste geothermal heat carrier in binary-cycle or combined-cycle power plants. The article provides data on a pilot binary power unit at Pauzhetka GPP and on a

  17. Geothermal development in the Philippines

    SciTech Connect

    Elizagaque, R.F.; Tolentino, B.S.

    1982-06-01

    The development of geothermal resources and energy in the Philippines is discussed. Philippine National Oil Company-Energy Development Corporation initiated the first semi-commercial generation of geothermal power in July 1977 with the installation of a 3MWe plant. By 1980 the country had 440 MWe on line at Mak-Ban and Tiwi. This placed the Philippines second after the US among countries using geothermal energy for power generation. Before the end of 1981, PNOC-EDC added 6 additional MWe of geothermal power generating capacity to increase the total to 446 MWe. As part of the five-year National Energy Development Programme covering the period 1981-1985, additional power plants will be installed in various project areas to increase the share of geothermal power generation from the present 9.8% to 18.6% of the nationwide power-generation total, or the equivalent of 16.6 million barrels of oil per year. (MJF)

  18. Geothermal resource data base: Arizona

    SciTech Connect

    Witcher, J.C.

    1995-09-01

    This report provides a compilation of geothermal well and spring information in Arizona up to 1993. This report and data base are a part of a larger congressionally-funded national effort to encourage and assist geothermal direct-use. In 1991, the US Department of Energy, Geothermal Division (DOE/GD) began a Low-Temperature Geothermal Resources and Technology Transfer Program. Phase 1 of this program includes updating the inventory of wells and springs of ten western states and placing these data into a digital format that is universally accessible to the PC. The Oregon Institute of Technology GeoHeat Center (OIT) administers the program and the University of Utah Earth Sciences and Resources Institute (ESRI) provides technical direction. In recent years, the primary growth in geothermal use in Arizona has occurred in aquaculture. Other uses include minor space heating and supply of warm mineral waters for health spas.

  19. Environmental Assessment Lakeview Geothermal Project

    SciTech Connect

    Treis, Tania

    2012-04-30

    The Town of Lakeview is proposing to construct and operate a geothermal direct use district heating system in Lakeview, Oregon. The proposed project would be in Lake County, Oregon, within the Lakeview Known Geothermal Resources Area (KGRA). The proposed project includes the following elements: Drilling, testing, and completion of a new production well and geothermal water injection well; construction and operation of a geothermal production fluid pipeline from the well pad to various Town buildings (i.e., local schools, hospital, and Lake County Industrial Park) and back to a geothermal water injection well. This EA describes the proposed project, the alternatives considered, and presents the environmental analysis pursuant to the National Environmental Policy Act. The project would not result in adverse effects to the environment with the implementation of environmental protection measures.

  20. 2008 Geothermal Technologies Market Report

    SciTech Connect

    Jonathan Cross

    2009-07-01

    This report describes market-wide trends for the geothermal industry throughout 2008 and the beginning of 2009. It begins with an overview of the GTP’s involvement with the geothermal industry and recent investment trends for electric generation technologies. The report next describes the current state of geothermal power generation and activity within the United States, costs associated with development, financing trends, an analysis of the levelized cost of energy (LCOE), and a look at the current policy environment. The report also highlights trends regarding direct use of geothermal energy, including GHPs.† The final sections of the report focus on international perspectives, employment and economic benefits from geothermal energy development, and potential incentives in pending national legislation.

  1. Geopressured geothermal bibliography (Geopressure Thesaurus)

    SciTech Connect

    Hill, T.R.; Sepehrnoori, K.

    1981-08-01

    This thesaurus of terminology associated with the geopressured geothermal energy field has been developed as a part of the Geopressured Geothermal Information System data base. A thesaurus is a compilation of terms displaying synonymous, hierarchical, and other relationships between terms. These terms, which are called descriptors, constitute the special language of the information retrieval system, the system vocabulary. The Thesaurus' role in the Geopressured Geothermal Information System is to provide a controlled vocabulary of sufficient specificity for subject indexing and retrieval of documents in the geopressured geothermal energy field. The thesauri most closely related to the Geopressure Thesaurus in coverage are the DOE Energy Information Data Base Subject Thesaurus and the Geothermal Thesaurus being developed at the Lawrence Berkeley Laboratory (LBL). The Geopressure Thesaurus differs from these thesauri in two respects: (1) specificity of the vocabulary or subject scope and (2) display format.

  2. Geothermal developments in the Philippines, 1980

    SciTech Connect

    Finn, D.F.X.

    1980-09-01

    The Philippines installed a 3MW geothermal in 1977, 55 MW in 1978, and 165 MW in 1979 and proposes to install 223 MW during 1980 to bring it's total installed geothermal generating capacity to 446 MW. An additional 223 MW geothermal has been proven and a goal of 1261 MW has been set for 1989 from eight geothermal fields.

  3. Geothermal resource evaluation of the Yuma area

    SciTech Connect

    Poluianov, E.W.; Mancini, F.P.

    1985-11-29

    This report presents an evaluation of the geothermal potential of the Yuma, Arizona area. A description of the study area and the Salton Trough area is followed by a geothermal analysis of the area, a discussion of the economics of geothermal exploration and exploitation, and recommendations for further testing. It was concluded economic considerations do not favor geothermal development at this time. (ACR)

  4. Geothermal Small Business Workbook [Geothermal Outreach and Project Financing

    SciTech Connect

    Elizabeth Battocletti

    2003-05-01

    Small businesses are the cornerstone of the American economy. Over 22 million small businesses account for approximately 99% of employers, employ about half of the private sector workforce, and are responsible for about two-thirds of net new jobs. Many small businesses fared better than the Fortune 500 in 2001. Non-farm proprietors income rose 2.4% in 2001 while corporate profits declined 7.2%. Yet not all is rosy for small businesses, particularly new ones. One-third close within two years of opening. From 1989 to 1992, almost half closed within four years; only 39.5% were still open after six years. Why do some new businesses thrive and some fail? What helps a new business succeed? Industry knowledge, business and financial planning, and good management. Small geothermal businesses are no different. Low- and medium-temperature geothermal resources exist throughout the western United States, the majority not yet tapped. A recent survey of ten western states identified more than 9,000 thermal wells and springs, over 900 low- to moderate-temperature geothermal resource areas, and hundreds of direct-use sites. Many opportunities exist for geothermal entrepreneurs to develop many of these sites into thriving small businesses. The ''Geothermal Small Business Workbook'' (''Workbook'') was written to give geothermal entrepreneurs, small businesses, and developers the tools they need to understand geothermal applications--both direct use and small-scale power generation--and to write a business and financing plan. The Workbook will: Provide background, market, and regulatory data for direct use and small-scale (< 1 megawatt) power generation geothermal projects; Refer you to several sources of useful information including owners of existing geothermal businesses, trade associations, and other organizations; Break down the complicated and sometimes tedious process of writing a business plan into five easy steps; Lead you--the geothermal entrepreneur, small company, or

  5. Geothermal direct-heat utilization assistance

    NASA Astrophysics Data System (ADS)

    The report summarizes activities of the Geo-Heat Center (GHC) at Oregon Institute of Technology for the first quarter of Fiscal Year 1995. It describes contacts with parties during this period related to assistance with geothermal direct heat projects. Areas dealt with include geothermal heat pumps, space heating, greenhouses, aquaculture, resources and equipment. Research is also being conducted on geothermal energy cost evaluation, low-temperature geothermal resource assessment, use of silica waste from the Cerro Prieto geothermal field as construction materials and geothermal heat pumps. Outreach activities include the publication of a quarterly bulletin on direct heat applications and dissemination of information on low-temperature geothermal resources and utilization.

  6. Parts, Materials, and Processes Experience Summary. Volume 1; [Catalog of ALERT and Other Information on Basic Design, Reliability, Quality and Applications Programs

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The ALERT program, a system for communicating common problems with parts, materials, and processes, is condensed and catalogued. Expanded information on selected topics is provided by relating the problem area (failure) to the cause, the investigations and findings, the suggestions for avoidance (inspections, screening tests, proper part applications), and failure analysis procedures. The basic objective of ALERT is the avoidance of the recurrence of parts, materials, and processed problems, thus improving the reliability of equipment produced for and used by the government.

  7. Geothermal Direct Heat Applications Program Summary

    SciTech Connect

    1981-09-25

    Because of the undefined risk in the development and use of geothermal energy as a thermal energy source, the Department of Energy Division of Geothermal Energy solicited competitive proposals for field experiments in the direct use of geothermal energy. Twenty-two proposals were selected for cost-shared funding with one additional project co-funded by the State of New Mexico. As expected, the critical parameter was developing a viable resource. So far, of the twenty resources drilled, fourteen have proved to be useful resources. These are: Boise, Idaho; Elko heating Company in Nevada; Pagosa Springs, Colorado; Philip School, Philip, South Dakota; St. Mary's Hospital, Pierre, South Dakota; Utah Roses near Salt Lake City; Utah State Prison, Utah; Warm Springs State Hospital, Montana; T-H-S Hospital, Marlin, Texas; Aquafarms International in the Cochella Valley, California; Klamath County YMCA and Klamath Falls in Oregon; Susanville, California and Monroe, utah. Monroe's 164 F and 600 gpm peak flow was inadequate for the planned project, but is expected to be used in a private development. Three wells encountered a resource insufficient for an economical project. These were Madison County at Rexburg, Idaho; Ore-Ida Foods at Ontario, Oregon and Holly Sugar at Brawley, California. Three projects have yet to confirm their resource. The Navarro College well in Corsicana, Texas is being tested; the Reno, Moana, Nevada well is being drilled and the El Centro, California well is scheduled to be drilled in January 1982. The agribusiness project at Kelly Hot Springs was terminated because a significant archeological find was encountered at the proposed site. The Diamond Ring Ranch in South Dakota, and the additional project, Carrie Tingley Hospital in Truth or Consequences, New Mexico both used existing wells. The projects that encountered viable resources have proceeded to design, construct, and in the most advanced projects, to operate geothermal systems for district

  8. Robust fusion with reliabilities weights

    NASA Astrophysics Data System (ADS)

    Grandin, Jean-Francois; Marques, Miguel

    2002-03-01

    The reliability is a value of the degree of trust in a given measurement. We analyze and compare: ML (Classical Maximum Likelihood), MLE (Maximum Likelihood weighted by Entropy), MLR (Maximum Likelihood weighted by Reliability), MLRE (Maximum Likelihood weighted by Reliability and Entropy), DS (Credibility Plausibility), DSR (DS weighted by reliabilities). The analysis is based on a model of a dynamical fusion process. It is composed of three sensors, which have each it's own discriminatory capacity, reliability rate, unknown bias and measurement noise. The knowledge of uncertainties is also severely corrupted, in order to analyze the robustness of the different fusion operators. Two sensor models are used: the first type of sensor is able to estimate the probability of each elementary hypothesis (probabilistic masses), the second type of sensor delivers masses on union of elementary hypotheses (DS masses). In the second case probabilistic reasoning leads to sharing the mass abusively between elementary hypotheses. Compared to the classical ML or DS which achieves just 50% of correct classification in some experiments, DSR, MLE, MLR and MLRE reveals very good performances on all experiments (more than 80% of correct classification rate). The experiment was performed with large variations of the reliability coefficients for each sensor (from 0 to 1), and with large variations on the knowledge of these coefficients (from 0 0.8). All four operators reveal good robustness, but the MLR reveals to be uniformly dominant on all the experiments in the Bayesian case and achieves the best mean performance under incomplete a priori information.

  9. Geothermal Technologies Program Blue Ribbon Panel Recommendations

    SciTech Connect

    none,

    2011-06-17

    The Geothermal Technologies Program assembled a geothermal Blue Ribbon Panel on March 22-23, 2011 in Albuquerque, New Mexico for a guided discussion on the future of geothermal energy in the United States and the role of the DOE Program. The Geothermal Blue Ribbon Panel Report captures the discussions and recommendations of the experts. An addendum is available here: http://www.eere.energy.gov/geothermal/pdfs/gtp_blue_ribbon_panel_report_addendum10-2011.pdf

  10. Materials for geothermal production

    SciTech Connect

    Kukacka, L.E.

    1992-01-01

    Advances in the development of new materials continue to be made in the geothermal materials project. Many successes have already been accrued and the results used commercially. In FY 1991, work was focused on reducing well drilling, fluid transport and energy conversion costs. Specific activities performed included lightweight CO{sub 2}-resistant well cements, thermally conductive and scale resistant protective liner systems, chemical systems for lost circulation control, corrosion mitigation in process components at The Geysers, and elastomer-metal bonding systems. Efforts to transfer the technologies developed in these efforts to other energy-related sectors of the economy continued and considerable success was achieved.

  11. Direct utilization of geothermal energy for Pagosa Springs, Colorado. Final report, June 1979-June 1984

    SciTech Connect

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

    1984-08-01

    The Pagosa Springs Geothermal District Heating System was conceptualized, designed, and constructed between 1979 to 1984 under the US Department of Energy Program Opportunity Notice (PON) program to demonstrate the feasibility for utilizing moderate temperature geothermal resources for direct-use applications. The Pagosa Springs system successfully provides space heating to public buildings, school facilities, residences, and commercial establishments at costs significantly lower than costs of available conventional fuels. The Pagosa Springs project encompassed a full range of technical, institutional, and economic activities. Geothermal reservoir evaluations and testing were performed, and two productive approx.140/sup 0/F geothermal supply wells were successfully drilled and completed. Transmission and distribution system design, construction, startup, and operation were achieved with minimum difficulty. The geothermal system operation during the first two heating seasons has been fully reliable and well respected in the community. The project has proven that low to moderate-temperature waters can effectively meet required heating loads, even for harsh winter-mountain environments. The principal difficulty encountered has been institutional in nature and centers on the obtaining of the geothermal production well permits and the adjudicated water rights necessary to supply the geothermal hot water fluids for the full operating life of the system. 28 figs., 15 tabs.

  12. Reliability generalization: a viable key for establishing validity generalization

    NASA Technical Reports Server (NTRS)

    Kennedy, R. S.; Turnage, J. J.

    1991-01-01

    Even with radical restriction of range, reliability coefficients from 10 studies gave an average interstudy value of .74, suggesting constancy of reliability over diverse experiments. A value from a new test can help index reliability of tests not previously studied.

  13. Geothermal development plan: Pima County

    NASA Astrophysics Data System (ADS)

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

    1982-08-01

    The Pima County Area Development evaluated the county-wide market potential for utilizing geothermal energy. Four potential geothermal resource areas with temperatures less than 1000 C (2120 F) were identified. In addition, one area is identified as having a temperature of 1470 F (2970 F). Geothermal resources are found to occur in Tecson where average population growth rates of two to three percent per year are expected over the next 40 years. Rapid growth in the manufacturing sector and the existence of major copper mines provide opportunities for the direct utilization of geothermal energy. However, available water supplies are identified as a major constraing to projected growth. A regional energy analysis, future predictions for energy consumption, and energy prices are given. Potential geothermal users in Pima County are identified and projections of maximum economic geothermal utilization are given. One hundred fifteen firms in 32 industrial classes have some potential for geothermal use are identified. In addition, 26 agribusiness firms were found in the county.

  14. Geothermal development plan: Yuma County

    SciTech Connect

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

    1982-08-01

    The Yuma County Area Development Plan evaluated the county-wide market potential for utilizing geothermal energy. The study identified four potential geothermal resource areas with temperatures less than 90/sup 0/C (194/sup 0/F), and in addition, two areas are inferred to contain geothermal resources with intermediate (90/sup 0/C to 150/sup 0/C, 194/sup 0/F to 300/sup 0/F) temperature potential. The resource areas are isolated, although one resource area is located near Yuma, Arizona. One resource site is inferred to contain a hot dry rock resource. Anticipated population growth in the county is expected to be 2 percent per year over the next 40 years. The primary employment sector is agriculture, though some light industry is located in the county. Water supplies are found to be adequate to support future growth without advese affect on agriculture. Six firms were found in Yuma County which may be able to utilize geothermal energy for process heat needs. In addition, several agricultural processors were found, concentrated in citrus processing and livestock raising. Geothermal energy utilization projections suggest that by the year 2000, geothermal energy may economically provide the energy equivalent of 53,000 barrels of oil per year to the industrial sector if developed privately. Geothermal utilization projections increase to 132,000 barrels of oil per year by 2000 if a municipal utility developed the resource.

  15. Geothermal heating for Caliente, Nevada

    SciTech Connect

    Wallis, F.; Schaper, J.

    1981-02-01

    Utilization of geothermal resources in the town of Caliente, Nevada (population 600) has been the objective of two grants. The first grant was awarded to Ferg Wallis, part-owner and operator of the Agua Caliente Trailer Park, to assess the potential of hot geothermal water for heating the 53 trailers in his park. The results from test wells indicate sustainable temperatures of 140/sup 0/ to 160/sup 0/F. Three wells were drilled to supply all 53 trailers with domestic hot water heating, 11 trailers with space heating and hot water for the laundry from the geothermal resource. System payback in terms of energy cost-savings is estimated at less than two years. The second grant was awarded to Grover C. Dils Medical Center in Caliente to drill a geothermal well and pipe the hot water through a heat exchanger to preheat air for space heating. This geothermal preheater served to convert the existing forced air electric furnace to a booster system. It is estimated that the hospital will save an average of $5300 in electric bills per year, at the current rate of $.0275/KWH. This represents a payback of approximately two years. Subsequent studies on the geothermal resource base in Caliente and on the economics of district heating indicate that geothermal may represent the most effective supply of energy for Caliente. Two of these studies are included as appendices.

  16. Photovoltaics Performance and Reliability Workshop

    NASA Astrophysics Data System (ADS)

    Mrig, L.

    This document consists of papers and viewgraphs compiled from the proceedings of a workshop held in September 1992. This workshop was the fifth in a series sponsored by NREL/DOE under the general subject areas of photovoltaic module testing and reliability. PV manufacturers, DOE laboratories, electric utilities, and others exchanged technical knowledge and field experience. The topics of cell and module characterization, module and system performance, materials and module durability/reliability research, solar radiation, and applications are discussed.

  17. Geothermal pipeline: Progress and development update from the geothermal progress monitor

    SciTech Connect

    1995-10-01

    This document is a Progress and Development Update from the Geothermal Progress Monitor. It contains brief descriptions of progress made on varying projects involving the use of geothermal resources or research about geothermal systems. This article describes the following projects: Conversion of waste water to geothermal energy in Northern California, Hydrogen sulfide study in Hawaii, a new program at the Cerro Prieto geothermal resource in Mexico, geothermal heating of a Nevadan school, development of a geothermal fluid standard, and the broadcasting of geothermal teleconferences.

  18. Tracing Geothermal Fluids

    SciTech Connect

    Michael C. Adams; Greg Nash

    2004-03-01

    Geothermal water must be injected back into the reservoir after it has been used for power production. Injection is critical in maximizing the power production and lifetime of the reservoir. To use injectate effectively the direction and velocity of the injected water must be known or inferred. This information can be obtained by using chemical tracers to track the subsurface flow paths of the injected fluid. Tracers are chemical compounds that are added to the water as it is injected back into the reservoir. The hot production water is monitored for the presence of this tracer using the most sensitive analytic methods that are economically feasible. The amount and concentration pattern of the tracer revealed by this monitoring can be used to evaluate how effective the injection strategy is. However, the tracers must have properties that suite the environment that they will be used in. This requires careful consideration and testing of the tracer properties. In previous and parallel investigations we have developed tracers that are suitable from tracing liquid water. In this investigation, we developed tracers that can be used for steam and mixed water/steam environments. This work will improve the efficiency of injection management in geothermal fields, lowering the cost of energy production and increasing the power output of these systems.

  19. Time frames for geothermal project development

    SciTech Connect

    McClain, David W.

    2001-04-17

    Geothermal development can generally be broken down into distinct phases: Exploration and Leasing; Project Development And Feasibility Studies; Well Field Development; Project Finance, Construction and Start-up Operations; and Commercial Operations. Each phase represents different levels of cost and risk and different types of management teams that are needed to assess and manage the project and associated risk. Orderly transitions of management at each major phase are needed. Exploration programs are largely science based, the primary focus of the science based investigations should be to: secure the lease position, and develop sufficient information to identify and characterize an economical geothermal resource. Project development specialists build on the exploration data to: pull together a project design, develop a detailed cost estimate; prepare an environmental assessment; and collect all data needed for project financing. Construction specialist build from the development phase to: develop detailed engineering, procure equipment and materials, schedule and manage the facilities construction programs, and start and test the power plant. Operations specialists take over from construction during start-up and are responsible for sustainable and reliable operations of the resource and power generation equipment over the life of the project.

  20. Software reliability studies

    NASA Technical Reports Server (NTRS)

    Hoppa, Mary Ann; Wilson, Larry W.

    1994-01-01

    There are many software reliability models which try to predict future performance of software based on data generated by the debugging process. Our research has shown that by improving the quality of the data one can greatly improve the predictions. We are working on methodologies which control some of the randomness inherent in the standard data generation processes in order to improve the accuracy of predictions. Our contribution is twofold in that we describe an experimental methodology using a data structure called the debugging graph and apply this methodology to assess the robustness of existing models. The debugging graph is used to analyze the effects of various fault recovery orders on the predictive accuracy of several well-known software reliability algorithms. We found that, along a particular debugging path in the graph, the predictive performance of different models can vary greatly. Similarly, just because a model 'fits' a given path's data well does not guarantee that the model would perform well on a different path. Further we observed bug interactions and noted their potential effects on the predictive process. We saw that not only do different faults fail at different rates, but that those rates can be affected by the particular debugging stage at which the rates are evaluated. Based on our experiment, we conjecture that the accuracy of a reliability prediction is affected by the fault recovery order as well as by fault interaction.

  1. Tailored Working Fluids for Enhanced Binary Geothermal Power Plants

    SciTech Connect

    Mahmoud, Ahmad

    2013-01-29

    United Technologies Research Center (UTRC), in collaboration with the Georgia Institute of Technology and the National Institute of Standards and Technology will evaluate and develop fundamental and component level models, conduct experiments and generate data to support the use of mixed or enhanced working fluids for geothermal power generation applications.

  2. Geothermal development plan: northern Arizona

    SciTech Connect

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

    1981-01-01

    Much of the northern counties (Apache, Coconino, Gila, Mohave, Navajo and Yavapai) is located in the Colorado Plateau province, a region of low geothermal potential. Two areas that do show some potential are the Flagstaff - San Francisco Peaks area and the Springerville area. Flagstaff is rapidly becoming the manufacturing center of Arizona and will have many opportunities to use geothermal energy to satisfy part of its increasing need for energy. Using a computer simulation model, projections of geothermal energy on line as a function of time are made for both private and city-owned utility development of a resource.

  3. Hydraulic fracture stimulation treatment of Well Baca 23. Geothermal Reservoir Well-Stimulation Program

    SciTech Connect

    Not Available

    1981-06-01

    Well Stimulation Experiment No. 5 of the Geothermal Reservoir Well Stimulation Program (GRWSP) was performed on March 22, 1981 in Baca 23, located in Union's Redondo Creek Project Area in Sandoval County, New Mexico. The treatment selected was a large hydraulic fracture job designed specifically for, and utilizing frac materials chosen for, the high temperature geothermal environment. The well selection, fracture treatment, experiment evaluation, and summary of the job costs are presented herein.

  4. NREL Geothermal Policymakers' Guidebooks Web site (Fact Sheet)

    SciTech Connect

    Not Available

    2010-10-01

    This document highlights the NREL Geothermal Policymakers' Guidebooks Web site, including the five steps to effective geothermal policy development for geothermal electricity generation and geothermal heating and cooling technologies.

  5. What is an Enhanced Geothermal System (EGS)? Fact Sheet

    SciTech Connect

    U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy

    2012-09-14

    This Geothermal Technologies Office fact sheet explains how engineered geothermal reservoirs called Enhanced Geothermal Systems are used to produce energy from geothermal resources that are otherwise not economical due to a lack of fluid and/or permeability.

  6. Geothermal Technology Evolution Rationale for the National Energy Strategy

    SciTech Connect

    1990-10-01

    The DOE developed ''Technology Evolution Rationale'' documents for many of its technology development programs, at this time (report is dated October 1, 1990). This is a very significant description of the status of resources, technology, and industry in 1990, and the thinking that guided the DOE Geothermal Research Program at this time. The report describes: Geothermal energy conversion and use technologies, Resources and land use, Stakeholder and users, Industry status, and Market acceptance and experience in the U.S. The Economic status chapter covers Figures of Merit for assessing geothermal energy systems, and trends in geothermal development. The chapter on Cost/performance projections provides much detail on estimates of system costs, and projections for how DOE R&D would likely affect those costs. The Rationale chapter provides much detail on how subsystems are linked together to provide system performance and cost estimates, and details of technology improvements being worked on that are likely to reduce the cost of power from geothermal. Includes references (citations) to the background studies used to develop the details here. (DJE 2005)

  7. Geothermal Energy Production With Innovative Methods Of Geothermal Heat Recovery

    SciTech Connect

    Swenson, Allen; Darlow, Rick; Sanchez, Angel; Pierce, Michael; Sellers, Blake

    2014-12-19

    The ThermalDrive™ Power System (“TDPS”) offers one of the most exciting technological advances in the geothermal power generation industry in the last 30 years. Using innovations in subsurface heat recovery methods, revolutionary advances in downhole pumping technology and a distributed approach to surface power production, GeoTek Energy, LLC’s TDPS offers an opportunity to change the geothermal power industry dynamics.

  8. Development and evaluation of elastomeric materials for geothermal applications

    NASA Technical Reports Server (NTRS)

    Mueller, W. A.; Kalfayan, S. H.; Reilly, W. W.; Ingham, J. D.

    1978-01-01

    A material for a casing packer for service for 24 hours in a geothermal environment was developed by synthesis of new elastomers and formulation of available materials. Formulation included use of commercial elastomer gumstocks and also crosslinking of plastic (high Tg) materials. Fibrous reinforcement of fluorocarbon rubbers was emphasized. Organic fiber reinforcement did not increase hot properties significantly. Glass fiber reinforcement gave significant increase in tensile properties. Elongation was reduced, and the glass-reinforced composition examined so far did not hold up well in the geothermal environment. Colloidal asbestos fibers were also investigated. A few experiments with polyphenyl ether gave material with low tensile and high compression set. Available high styrene SBR compositions were studied. Work to date suggests that new synthetic polymers will be required for service in geothermal environments.

  9. Geothermal Power Development Resource Evaluation Aspects for Kyushu Electric Power Co., Inc., Fukuoka, Japan

    SciTech Connect

    1980-10-30

    This report is a limited review of and presents comments on the geothermal resource exploration program of Kyushu Electric Power Company (KEPCO). This program is for developing geothermal resources to generate electric power on Kyushu Island, Japan. Many organizations in Japan and in particular Kyushu Electric Power Co., Inc. are actively exploring for and developing geothermal resources on Kyushu Island. KEPCO has already demonstrated an ability and expertise to explore for geothermal resources by their successful exploration and subsequent development of several fields (Hatchobaru and Otake) on the island of Kyushu for electric power generation. The review and comments are made relative to the geothermal resource aspects of Kyushu Electric Power Company's geothermal exploration program, and within the time, budget, and scope of the Rogers Engineering's effort under the existing contract. Rogers and its consultants have had a wide variety of geothermal exploration experience and have used such experience in the analysis of what has been presented by KEPCO. The remainder of the introduction section develops general knowledge concerning geothermal power development with particular emphasis on the resource exploration. The data received section describes the information available to perform the project work. There are no interpretative parts to the data received section. The philosophy section relates our understanding of the KEPCO thinking and conditions surrounding current geothermal resource development in Japan. The survey and methods sections presents three important items about each study KEPCO has performed in the resource exploration program. These three aspects are: what should be obtained from the method, what data was obtained and presented, and what is a review and analysis of where the KEPCO exploration program is currently in terms of progress and successful location of reservoirs. The final section presents recommendations on the many aspects of the

  10. High Temperature Geothermal Elastomer Compund Development

    SciTech Connect

    Hirasuna, A. R.

    1981-01-01

    Reliable casting packer seal elastomers for the unusually severe geothermal environment at 260 C (500 F) did not exist in 1976. L'Garde, Inc., was awarded a contract to fulfill this need by the US Department of Energy. Successful development was completed in 1979. Compounds based on four different polymer systems were developed, all of which exceed the contract requirements. Successful laboratory tests above 300 C (575 F) have been performed with packer seals. Field tests to temperatures as high as 317 C (603 F) have been performed on static O-rings in a cablehead. Successful, dynamic, drill bit seal tests were run with a presoak temperature of 288 C (550 F). The successful compounds are based on the following polymer systems: EPDM; FKM; EPDM/FKM blend, and propylene-TFE.

  11. Research on geothermal chemistry and advanced instrumentation

    NASA Astrophysics Data System (ADS)

    Robertus, R. J.; Shannon, D. W.; Sullivan, R. G.; Kindle, C. H.; Pool, K. H.

    1985-09-01

    Research at the Pacific Northwest Laboratory (PNL) focuses on long-term geothermal power plant reliability. Past work concentrated on development of continuous high-temperature probes for monitoring process variables. PNL also completed a comprehensive handbook of brine treatment processes as they relate to injection well longevity. A recently completed study analyzed corrosion in the hydrocarbon system of a binary cycle plant. Over the two-year monitoring period, corrosion rates were less than 1 MPY in any part of the hydrocarbon system. The system was kept completely dry so the rates seem reasonable. Present projects include: (1) determination of gas breakout conditions at the Herber Binary Demonstration Plant operated by San Diego Gas and Electric Company; (2) generation of water mixing solubility data; (3) installation of prototype leak detectors at the Herber Plant; and (4) evaluation of state-of-the-art particle counters.

  12. Geothermal Data from the National Geothermal Data System (NGDS)

    DOE Data Explorer

    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 Energy’s 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.

  13. Geothermal Permeability Enhancement - Final Report

    SciTech Connect

    Joe Beall; Mark Walters

    2009-06-30

    The overall objective is to apply known permeability enhancement techniques to reduce the number of wells needed and demonstrate the applicability of the techniques to other undeveloped or under-developed fields. The Enhanced Geothermal System (EGS) concept presented in this project enhances energy extraction from reduced permeability zones in the super-heated, vapor-dominated Aidlin Field of the The Geysers geothermal reservoir. Numerous geothermal reservoirs worldwide, over a wide temperature range, contain zones of low permeability which limit the development potential and the efficient recovery of heat from these reservoirs. Low permeability results from poorly connected fractures or the lack of fractures. The Enhanced Geothermal System concept presented here expands these technologies by applying and evaluating them in a systematic, integrated program.

  14. Geothermal energy for American Samoa

    SciTech Connect

    Not Available

    1980-03-01

    The geothermal commercialization potential in American Samoa was investigated. With geothermal energy harnessed in American Samoa, a myriad of possibilities would arise. Existing residential and business consumers would benefit from reduced electricity costs. The tuna canneries, demanding about 76% of the island's process heat requirements, may be able to use process heat from a geothermal source. Potential new industries include health spas, aquaculture, wood products, large domestic and transhipment refrigerated warehouses, electric cars, ocean nodule processing, and a hydrogen economy. There are no territorial statutory laws of American Samoa claiming or reserving any special rights (including mineral rights) to the territorial government, or other interests adverse to a land owner, for subsurface content of real property. Technically, an investigation has revealed that American Samoa does possess a geological environment conducive to geothermal energy development. Further studies and test holes are warranted.

  15. Geothermal Program Review IV: proceedings

    SciTech Connect

    Not Available

    1985-01-01

    The research and development program of DOE's Geothermal Technology Division is reviewed in separate presentations according to program area. Separate abstracts have been prepared for the individual papers. (ACR)

  16. Process for cementing geothermal wells

    SciTech Connect

    Eilers, L. H.

    1985-12-03

    A pumpable slurry of coal-filled furfuryl alcohol, furfural, and/or a low molecular weight monoor copolymer thereof containing, preferably, a catalytic amount of a soluble acid catalyst is used to cement a casing in a geothermal well.

  17. SURFACE CONTAINMENT FOR GEOTHERMAL BRINES

    EPA Science Inventory

    This report examines the probability of significant releases of geothermal brine to the surface environment through unplanned or accidental events. It then evaluates the containment measures that may be used to prevent environmental damage. The results indicate that major spills ...

  18. Infants track the reliability of potential informants.

    PubMed

    Tummeltshammer, Kristen Swan; Wu, Rachel; Sobel, David M; Kirkham, Natasha Z

    2014-09-01

    Across two eye-tracking experiments, we showed that infants are sensitive to the statistical reliability of informative cues and selective in their use of information generated by such cues. We familiarized 8-month-olds with faces (Experiment 1) or arrows (Experiment 2) that cued the locations of animated animals with different degrees of reliability. The reliable cue always cued a box containing an animation, whereas the unreliable cue cued a box that contained an animation only 25% of the time. At test, infants searched longer in the boxes that were reliably cued, but did not search longer in the boxes that were unreliably cued. At generalization, when boxes were cued that never contained animations before, only infants in the face experiment followed the reliable cue. These results provide the first evidence that even young infants can track the reliability of potential informants and use this information judiciously to modify their future behavior. PMID:25022277

  19. Reliability model generator

    NASA Technical Reports Server (NTRS)

    McMann, Catherine M. (Inventor); Cohen, Gerald C. (Inventor)

    1991-01-01

    An improved method and system for automatically generating reliability models for use with a reliability evaluation tool is described. The reliability model generator of the present invention includes means for storing a plurality of low level reliability models which represent the reliability characteristics for low level system components. In addition, the present invention includes means for defining the interconnection of the low level reliability models via a system architecture description. In accordance with the principles of the present invention, a reliability model for the entire system is automatically generated by aggregating the low level reliability models based on the system architecture description.

  20. Geothermal energy abstract sets. Special report No. 14

    SciTech Connect

    Stone, C.

    1985-01-01

    This bibliography contains annotated citations in the following areas: (1) case histories; (2) drilling; (3) reservoir engineering; (4) injection; (5) geothermal well logging; (6) environmental considerations in geothermal development; (7) geothermal well production; (8) geothermal materials; (9) electric power production; (10) direct utilization of geothermal energy; (11) economics of geothermal energy; and (12) legal, regulatory and institutional aspects. (ACR)

  1. Tongonani geothermal power development, Philippines

    SciTech Connect

    Minson, A.A.C.; Fry, T.J.; Kivell, J.A.

    1985-01-01

    This paper describes the features, design and construction of a 112 MWe geothermal power project, representing the first stage development of the substantial geothermal resources of the central Philippine region. The project has been undertaken by the Philippine Government. The National Powe Corporation is responsible for generation and distribution facilities and the Philippine National Oil Company Energy Development Corporation is responsible for controlled delivery of steam to the powe station.

  2. The Marysville, Montana Geothermal Project

    NASA Technical Reports Server (NTRS)

    Mcspadden, W. R.; Stewart, D. H.; Kuwada, J. T.

    1974-01-01

    Drilling the first geothermal well in Montana presented many challenges, not only in securing materials and planning strategies for drilling the wildcat well but also in addressing the environmental, legal, and institutional issues raised by the request for permission to explore a resource which lacked legal definition. The Marysville Geothermal Project was to investigate a dry hot rock heat anomaly. The well was drilled to a total depth of 6790 feet and many fractured water bearing zones were encountered below 1800 feet.

  3. Computerized international geothermal information systems

    SciTech Connect

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

    1980-03-01

    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.

  4. Optimizing Sustainable Geothermal Heat Extraction

    NASA Astrophysics Data System (ADS)

    Patel, Iti; Bielicki, Jeffrey; Buscheck, Thomas

    2016-04-01

    Geothermal heat, though renewable, can be depleted over time if the rate of heat extraction exceeds the natural rate of renewal. As such, the sustainability of a geothermal resource is typically viewed as preserving the energy of the reservoir by weighing heat extraction against renewability. But heat that is extracted from a geothermal reservoir is used to provide a service to society and an economic gain to the provider of that service. For heat extraction used for market commodities, sustainability entails balancing the rate at which the reservoir temperature renews with the rate at which heat is extracted and converted into economic profit. We present a model for managing geothermal resources that combines simulations of geothermal reservoir performance with natural resource economics in order to develop optimal heat mining strategies. Similar optimal control approaches have been developed for managing other renewable resources, like fisheries and forests. We used the Non-isothermal Unsaturated-saturated Flow and Transport (NUFT) model to simulate the performance of a sedimentary geothermal reservoir under a variety of geologic and operational situations. The results of NUFT are integrated into the optimization model to determine the extraction path over time that maximizes the net present profit given the performance of the geothermal resource. Results suggest that the discount rate that is used to calculate the net present value of economic gain is a major determinant of the optimal extraction path, particularly for shallower and cooler reservoirs, where the regeneration of energy due to the natural geothermal heat flux is a smaller percentage of the amount of energy that is extracted from the reservoir.

  5. The Oregon Geothermal Planning Conference

    SciTech Connect

    1980-10-02

    Oregon's geothermal resources represent a large portion of the nation's total geothermal potential. The State's resources are substantial in size, widespread in location, and presently in various stages of discovery and utilization. The exploration for, and development of, geothermal is presently dependent upon a mixture of engineering, economic, environmental, and legal factors. In response to the State's significant geothermal energy potential, and the emerging impediments and incentives for its development, the State of Oregon has begun a planning program intended to accelerate the environmentally prudent utilization of geothermal, while conserving the resource's long-term productivity. The program, which is based upon preliminary work performed by the Oregon Institute of Technology's Geo-Heat Center, will be managed by the Oregon Department of Energy, with the assistance of the Departments of Economic Development, Geology and Mineral Industries, and Water Resources. Funding support for the program is being provided by the US Department of Energy. The first six-month phase of the program, beginning in July 1980, will include the following five primary tasks: (1) coordination of state and local agency projects and information, in order to keep geothermal personnel abreast of the rapidly expanding resource literature, resource discoveries, technological advances, and each agency's projects. (2) Analysis of resource commercialization impediments and recommendations of incentives for accelerating resource utilization. (3) Compilation and dissemination of Oregon geothermal information, in order to create public and potential user awareness, and to publicize technical assistance programs and financial incentives. (4) Resource planning assistance for local governments in order to create local expertise and action; including a statewide workshop for local officials, and the formulation of two specific community resource development plans. (5) Formulation and

  6. Geothermal greenhouses in Kyushu, Japan

    SciTech Connect

    Lienau, P.J.

    1996-05-01

    The New Energy Foundation (NEF) invited two members of the Geo-Heat Center staff of Tokyo to present two workshops on the direct uses of geothermal energy in the United States. Prior to the meetings, a field trip was arranged by NEF to visit geothermal power plants and direct use sites on Kyushu. Seven areas were toured on February 27 and 28th, including the Sensui Rose Garden greenhouse, a demonstration greenhouse at the Hatchobaru power station and the Kokonoe Bio Center.

  7. Geothermal Money Book [Geothermal Outreach and Project Financing

    SciTech Connect

    Elizabeth Battocletti

    2004-02-01

    Small business lending is big business and growing. Loans under $1 million totaled $460 billion in June 2001, up $23 billion from 2000. The number of loans under $100,000 continued to grow at a rapid rate, growing by 10.1%. The dollar value of loans under $100,000 increased 4.4%; those of $100,000-$250,000 by 4.1%; and those between $250,000 and $1 million by 6.4%. But getting a loan can be difficult if a business owner does not know how to find small business-friendly lenders, how to best approach them, and the specific criteria they use to evaluate a loan application. This is where the Geothermal Money Book comes in. Once a business and financing plan and financial proposal are written, the Geothermal Money Book takes the next step, helping small geothermal businesses locate and obtain financing. The Geothermal Money Book will: Explain the specific criteria potential financing sources use to evaluate a proposal for debt financing; Describe the Small Business Administration's (SBA) programs to promote lending to small businesses; List specific small-business friendly lenders for small geothermal businesses, including those which participate in SBA programs; Identify federal and state incentives which are relevant to direct use and small-scale (< 1 megawatt) power generation geothermal projects; and Provide an extensive state directory of financing sources and state financial incentives for the 19 states involved in the GeoPowering the West (GPW). GPW is a U.S. Department of Energy-sponsored activity to dramatically increase the use of geothermal energy in the western United States by promoting environmentally compatible heat and power, along with industrial growth and economic development. The Geothermal Money Book will not: Substitute for financial advice; Overcome the high exploration, development, and financing costs associated with smaller geothermal projects; Remedy the lack of financing for the exploration stage of a geothermal project; or Solve financing

  8. Enhanced Geothermal Systems

    SciTech Connect

    Jeanloz, R.; Stone, H.

    2013-12-31

    DOE, through the Geothermal Technologies Office (GTO) within the Office of Energy Efficiency and Renewable Energy, requested this study, identifying a focus on: i) assessment of technologies and approaches for subsurface imaging and characterization so as to be able to validate EGS opportunities, and ii) assessment of approaches toward creating sites for EGS, including science and engineering to enhance permeability and increase the recovery factor. Two days of briefings provided in-depth discussion of a wide range of themes and challenges in EGS, and represented perspectives from industry, government laboratories and university researchers. JASON also contacted colleagues from universities, government labs and industry in further conversations to learn the state of the field and potential technologies relevant to EGS.

  9. Geothermal development in Australia

    SciTech Connect

    Burns, K.L.; Creelman, R.A.; Buckingham, N.W.; Harrington, H.J. |

    1995-03-01

    In Australia, natural hot springs and hot artesian bores have been developed for recreational and therapeutic purposes. A district heating system at Portland, in the Otway Basin of western Victoria, has provided uninterrupted service for 12 Sears without significant problems, is servicing a building area of 18 990 m{sup 2}, and has prospects of expansion to manufacturing uses. A geothermal well has provided hot water for paper manufacture at Traralgon, in the Gippsland Basin of eastern Victoria. Power production from hot water aquifers was tested at Mulka in South Australia, and is undergoing a four-year production trial at Birdsville in Queensland. An important Hot Dry Rock resource has been confirmed in the Cooper Basin. It has been proposed to build an HDR experimental facility to test power production from deep conductive resources in the Sydney Basin near Muswellbrook.

  10. Geothermal innovative technologies catalog

    SciTech Connect

    Kenkeremath, D.

    1988-09-01

    The technology items in this report were selected on the basis of technological readiness and applicability to current technology transfer thrusts. The items include technologies that are considered to be within 2 to 3 years of being transferred. While the catalog does not profess to be entirely complete, it does represent an initial attempt at archiving innovative geothermal technologies with ample room for additions as they occur. The catalog itself is divided into five major functional areas: Exploration; Drilling, Well Completion, and Reservoir Production; Materials and Brine Chemistry; Direct Use; and Economics. Within these major divisions are sub-categories identifying specific types of technological advances: Hardware; Software; Data Base; Process/Procedure; Test Facility; and Handbook.

  11. Geothermal energy geopressure subprogram

    SciTech Connect

    Not Available

    1981-02-01

    The proposed action will consist of drilling one geopressured-geothermal resource fluid well for intermittent production testing over the first year of the test. During the next two years, long-term testing of 40,000 BPD will be flowed. A number of scenarios may be implemented, but it is felt that the total fluid production will approximate 50 million barrels. The test well will be drilled with a 22 cm (8.75 in.) borehole to a total depth of approximately 5185 m (17,000 ft). Up to four disposal wells will provide disposal of the fluid from the designated 40,000 BPD test rate. The following are included in this assessment: the existing environment; probable environmental impacts-direct and indirect; probable cumulative and long-term environmental impacts; accidents; coordination with federal, state, regional, and local agencies; and alternative actions. (MHR)

  12. Geothermal Resources Assessment in Hawaii

    SciTech Connect

    Thomas, D.M.

    1984-10-01

    The Hawaii Geothermal Resources Assessment Program was initiated in 1978. The preliminary phase of this effort identified 20 Potential Geothermal Resource Areas (PGRA's) using available geological, geochemical and geophysical data. The second phase of the Assessment Program undertook a series of field studies, utilizing a variety of geothermal exploration techniques, in an effort to confirm the presence of thermal anomalies in the identified PGRA's and, if confirmed, to more completely characterize them. A total of 15 PGRA's on four of the five major islands in the Hawaiian chain were subject to at least a preliminary field analysis. The remaining five were not considered to have sufficient resource potential to warrant study under the personnel and budget constraints of the program. The island of Kauai was not studied during the current phase of investigation. Geothermal field studies were not considered to be warranted due to the absence of significant geochemical or geophysical indications of a geothermal resource. The great age of volcanism on this island would further suggest that should a thermal resource be present, it would be of low temperature. The geothermal field studies conducted on Oahu focused on the caldera complexes of the two volcanic systems which form the island: Waianae volcano and Koolau volcano. The results of these studies and the interpreted probability for a resource are presented.

  13. Geothermal development plan: Maricopa County

    SciTech Connect

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

    1982-08-01

    The Maricopa County Geothermal Development Plan evaluated the market potential for utilizing geothermal energy. The study identified six potential geothermal resource areas with temperatures less than 100{sup 0}C (212{sup 0}F) and in addition, four suspected intermediate temperature areas (90{sup 0} to 150{sup 0}C, 194{sup 0} to 300{sup 0}F). Geothermal resources are found to occur in and near the Phoenix metropolitan area where average population growth rates of two to three percent per year are expected over the next 40 years. Rapid growth in the manufacturing, trade and service sectors of the regional economy provides opportunities for the direct utilization of geothermal energy. A regional energy use analysis is included containing energy use and price projections. Water supplies are found to be adequate to support this growth, though agricultural water use is expected to diminish. The study also contains a detailed section matching geothermal resources to potential users. Two comparative analyses providing economic details for space heating projects are incorporated.

  14. Geothermal systems: Principles and case histories

    NASA Astrophysics Data System (ADS)

    Rybach, L.; Muffler, L. J. P.

    The classification of geothermal systems is considered along with the geophysical and geochemical signatures of geothermal systems, aspects of conductive heat transfer and regional heat flow, and geothermal anomalies and their plate tectonic framework. An investigation of convective heat and mass transfer in hydrothermal systems is conducted, taking into account the mathematical modelling of hydrothermal systems, aspects of idealized convective heat and mass transport, plausible models of geothermal reservoirs, and preproduction models of hydrothermal systems. Attention is given to the prospecting for geothermal resources, the application of water geochemistry to geothermal exploration and reservoir engineering, heat extraction from geothermal reservoirs, questions of geothermal resource assessment, and environmental aspects of geothermal energy development. A description is presented of a number of case histories, taking into account the low enthalpy geothermal resource of the Pannonian Basin in Hungary, the Krafla geothermal field in Northeast Iceland, the geothermal system of the Jemez Mountains in New Mexico, and extraction-reinjection at the Ahuachapan geothermal field in El Salvador.

  15. Reliability Generalization: "Lapsus Linguae"

    ERIC Educational Resources Information Center

    Smith, Julie M.

    2011-01-01

    This study examines the proposed Reliability Generalization (RG) method for studying reliability. RG employs the application of meta-analytic techniques similar to those used in validity generalization studies to examine reliability coefficients. This study explains why RG does not provide a proper research method for the study of reliability,…

  16. Microbiological monitoring in geothermal plants and a cold storage

    NASA Astrophysics Data System (ADS)

    Alawi, Mashal; Lerm, Stephanie; Vieth, Andrea; Vetter, Alexandra; Miethling-Graff, Rona; Seibt, Andrea; Wolfgramm, Markus; Würdemann, Hilke

    2010-05-01

    Enhanced process understanding of engineered geothermal systems is mandatory to optimize plant reliability and economy. In the scope of the research project 'AquiScreen' we investigated geothermally used groundwater systems under microbial, geochemical, mineralogical and petrological aspects. Geothermal systems located in the North German Basin and the Molasse Basin were analyzed by sampling of fluids and solid phases. The investigated sites were characterized by different temperatures, salinities and potential microbial substrates. The microbial population was analyzed by the use of genetic fingerprinting techniques based on PCR-amplified 16S rRNA genes. Sequencing of dominant bands of fingerprints from different sites and the subsequent comparison on public databases enables a correlation to metabolic classes and provides information about the biochemical processes. In all investigated geothermal plants covering a temperature range from 45° to 120° C microorganisms were found. Phylogenetic gene analyses indicate a broad diversity of microorganisms adapted to the specific conditions in the engineered system. Beside characterized bacteria like Thermus scotoductus, Siderooxidans lithoautotrophicus and the archaeon Methanothermobacter thermoautotrophicus a high number of so far uncultivated microorganisms was detected. As it is known that -in addition to abiotic factors- microbes like sulfate-reducing bacteria (SRB) are involved in the processes of corrosion and scaling in plant components we identified SRB by specific analyses of dissimilatoric sulfite reductase genes. The SRB detected are closely related to thermotolerant and thermophilic species of Desulfotomaculum, Thermodesulfovibrio and Thermodesulfobacterium, respectively. Overall, the detection of microbes known to be involved in biocorrosion and examined precipitation products like iron sulfides are indicating that microorganisms play an important role for the understanding of processes in engineered

  17. Geothermal well stimulated using High Energy Gas Fracturing

    SciTech Connect

    Chu, T.Y.; Jacobson, R.D.; Warpinski, N.; Mohaupt, H.

    1987-01-01

    This paper reports the result of an experimental study of the High Energy Gas Fracturing (HEGF) technique for geothermal well stimulation. These experiments demonstrated that multiple fractures could be created to link a water-filled borehole with other fractures. The resulting fracture network and fracture interconnections were characterized by flow tests as well as mine back. Commercial oil field fracturing tools were used successfully in these experiments.

  18. Geothermal Well Stimulated Using High Energy Gas Fracturing

    SciTech Connect

    Chu, T.Y.; Jacobson, R.D.; Warpinski, N.; Mohaupt, Henry

    1987-01-20

    This paper reports the result of an experimental study of the High Energy Gas Fracturing (HEGF) technique for geothermal well stimulation. These experiments demonstrated that multiple fractures could be created to link a water-filled borehole with other fractures. The resulting fracture network and fracture interconnections were characterized by flow tests as well as mine back. Commercial oil field fracturing tools were used successfully in these experiments. 5 refs., 2 tabs., 5 figs.

  19. Geothermal -- The Energy Under Our Feet: Geothermal Resource Estimates for the United States

    SciTech Connect

    Green, B. D.; Nix, R. G.

    2006-11-01

    On May 16, 2006, the National Renewable Energy Laboratory (NREL) in Golden, Colorado hosted a geothermal resources workshop with experts from the geothermal community. The purpose of the workshop was to re-examine domestic geothermal resource estimates. The participating experts were organized into five working groups based on their primary area of expertise in the following types of geothermal resource or application: (1) Hydrothermal, (2) Deep Geothermal Systems, (3) Direct Use, (4) Geothermal Heat Pumps (GHPs), and (5) Co-Produced and Geopressured. The workshop found that the domestic geothermal resource is very large, with significant benefits.

  20. Active Seismic Imaging Experiment

    NASA Astrophysics Data System (ADS)

    Berge, Patricia A.; Dawson, Phillip B.; Evans, John R.

    In September 1985 the U.S. Geological Survey (USGS) and Lawrence Livermore National Laboratory (LLNL) will conduct an active seismic experiment in the Medicine Lake area of northern California. The work is supported by the Geothermal Research Program of USGS and by the Geothermal and Hydropower Technologies Division of the U.S. Department of Energy. We invite interested organizations or individuals to record our explosions from Medicine Lake volcano and surrounding areas not covered by the USGS-LLNL array.

  1. Hydraulic fracturing in granite under geothermal conditions

    USGS Publications Warehouse

    Solberg, P.; Lockner, D.; Byerlee, J.D.

    1980-01-01

    The experimental hydraulic fracturing of granite under geothermal conditions produces tensile fracture at rapid fluid injection rates and shear fracture at slow injection rates and elevated differential stress levels. A sudden burst of acoustic emission activity accompanies tensile fracture formation whereas the acoustic emission rate increases exponentially prior to shear fracture. Temperature does not significantly affect the failure mechanism, and the experimental results have not demonstrated the occurrence of thermal fracturing. A critical result of these experiments is that fluid injection at intermediate rates and elevated differential stress levels increases permeability by more than an order of magnitude without producing macroscopic fractures, and low-level acoustic emission activity occurs simultaneously near the borehole and propagates outward into the specimen with time. Permeability measurements conducted at atmospheric pressure both before and after these experiments show that increased permeability is produced by permanent structural changes in the rock. Although results of this study have not demonstrated the occurrence of thermal fracturing, they suggest that fluid injection at certain rates in situ may markedly increase local permeability. This could prove critical to increasing the efficiency of heat exchange for geothermal energy extraction from hot dry rock. ?? 1980.

  2. Geothermal Energy Program Overview: Fiscal Year 1991

    SciTech Connect

    Not Available

    1991-12-01

    In FY 1990-1991, the Geothermal Energy Program made significant strides in hydrothermal, geopressured brine, hot dry rock, and magma research, continuing a 20-year tradition of advances in geothermal technology.

  3. POLLUTION CONTROL GUIDANCE FOR GEOTHERMAL ENERGY DEVELOPMENT

    EPA Science Inventory

    This report summarizes the EPA regulatory approach toward geothermal energy development. The state of knowledge is described with respect to the constituents of geothermal effluents and emissions, including water, air, solid wastes, and noise. Pollutant effects are discussed. Pol...

  4. Imperial County geothermal development annual meeting: summary

    SciTech Connect

    Not Available

    1983-01-01

    All phases of current geothermal development in Imperial County are discussed and future plans for development are reviewed. Topics covered include: Heber status update, Heber binary project, direct geothermal use for high-fructose corn sweetener production, update on county planning activities, Brawley and Salton Sea facility status, status of Imperial County projects, status of South Brawley Prospect 1983, Niland geothermal energy program, recent and pending changes in federal procedures/organizations, plant indicators of geothermal fluid on East Mesa, state lands activities in Imperial County, environmental interests in Imperial County, offshore exploration, strategic metals in geothermal fluids rebuilding of East Mesa Power Plant, direct use geothermal potential for Calipatria industrial Park, the Audubon Society case, status report of the Cerro Prieto geothermal field, East Brawley Prospect, and precision gravity survey at Heber and Cerro Prieto geothermal fields. (MHR)

  5. Fifteenth workshop on geothermal reservoir engineering: Proceedings

    SciTech Connect

    Not Available

    1990-01-01

    The Fifteenth Workshop on Geothermal Reservoir Engineering was held at Stanford University on January 23--25, 1990. Major topics included: DOE's geothermal research and development program, well testing, field studies, geosciences, geysers, reinjection, tracers, geochemistry, and modeling.

  6. An Evaluation of Enhanced Geothermal Systems Technology

    SciTech Connect

    Jelacic, Allan; Fortuna, Raymond; LaSala, Raymond; Nathwani, Jay; Nix, Gerald; Visser, Charles; Green, Bruce; Renner, Joel; Blankenship, Douglas; Kennedy, Mack; Bruton, Carol

    2008-04-01

    This 2008 document presents the results of an eight-month study by the Department of Energy (DOE) and its support staff at the national laboratories concerning the technological requirements to commercialize a new geothermal technology, Enhanced Geothermal Systems (EGS).

  7. Choosing a Geothermal as an HVAC System.

    ERIC Educational Resources Information Center

    Lensenbigler, John D.

    2002-01-01

    Describes the process of selecting and installing geothermal water source heat pumps for new residence halls at Johnson Bible College in Knoxville, Tennessee, including choosing the type of geothermal design, contractors, and interior equipment, and cost and payback. (EV)

  8. Geothermal Energy: Evaluation of a Resource

    ERIC Educational Resources Information Center

    Bockemuehl, H. W.

    1976-01-01

    This article suggests the use of geothermal energy for producing electricity, using as an example the development at Wairakei, New Zealand. Other geothermal areas are identified, and economic and environmental co sts of additional development are explored. (Author/AV)

  9. Pagosa Springs geothermal project. Final technical report

    SciTech Connect

    Not Available

    1984-10-19

    This booklet discusses some ideas and methods for using Colorado geothermal energy. A project installed in Pagosa Springs, which consists of a pipeline laid down 8th street with service to residences retrofitted to geothermal space heating, is described. (ACR)

  10. ANALYSIS OF GEOTHERMAL WASTES FOR HAZARDOUS COMPONENTS

    EPA Science Inventory

    Regulations governing the disposal of hazardous wastes led to an assessment for geothermal solid wastes for potentially hazardous properties. Samples were collected from three active geothermal sites in the western United States: The Geysers, Imperial Valley, and northwestern Nev...

  11. Can There Be Reliability without "Reliability?"

    ERIC Educational Resources Information Center

    Mislevy, Robert J.

    2004-01-01

    An "Educational Researcher" article by Pamela Moss (1994) asks the title question, "Can there be validity without reliability?" Yes, she answers, if by reliability one means "consistency among independent observations intended as interchangeable" (Moss, 1994, p. 7), quantified by internal consistency indices such as KR-20 coefficients and…

  12. HELIOS Critical Design Review: Reliability

    NASA Technical Reports Server (NTRS)

    Benoehr, H. C.; Herholz, J.; Prem, H.; Mann, D.; Reichert, L.; Rupp, W.; Campbell, D.; Boettger, H.; Zerwes, G.; Kurvin, C.

    1972-01-01

    This paper presents Helios Critical Design Review Reliability form October 16-20, 1972. The topics include: 1) Reliability Requirement; 2) Reliability Apportionment; 3) Failure Rates; 4) Reliability Assessment; 5) Reliability Block Diagram; and 5) Reliability Information Sheet.

  13. Geothermal Heat Pumps for Federal Buildings

    SciTech Connect

    1999-08-01

    OFFICE OF GEOTHERMAL TECHNOLOGIES Geothermal Heat Pumps for Federal Buildings The U.S. Government spends approximately $8 billion annually on its energy needs. To reduce energy use in Federal buildings, President Bill Clinton issued Executive Order 13123 in June 1999, which calls for a 35% reduction in Federal energy use from 1985 levels by 2010. Geothermal heat pumps--when installed in virtually any type of building--can help accomplish this goal with energy savings of up to 40%. Geothermal he.

  14. Geothermal reservoir engineering research at Stanford University. First annual report, October 1, 1980-September 30, 1981

    SciTech Connect

    Brigham, W.E.; Horne, R.N.; Kruger, P.; Miller, F.G.; Ramey, H.J. Jr.

    1981-09-01

    The work on energy extraction experiments concerns the efficiency with which the in-place heat and fluids can be produced. The work on noncondensable gas reservoir engineering covers both the completed and continuing work in these two interrelated research areas: radon emanation from the rock matrix of geothermal reservoirs, and radon and ammonia variations with time and space over geothermal reservoirs. Cooperative research programs with Italy and Mexico are described. The bench-scale experiments and well test analysis section covers both experimental and theoretical studies. The small core model continues to be used for the study of temperature effects on absolute permeability. The unconsolidated sand study was completed at the beginning of this contract period. The Appendices describe some of the Stanford Geothermal program activities that results in interactions with the geothermal community. These occur in the form of SGP Technical Reports, presentations at technical meetings and publications in the open literature.

  15. Utilization of geothermal energy in the Philippines

    SciTech Connect

    Rivero, L.U.; De La Salle Univ, M.

    1981-01-01

    A history of the exploration of the geothermal resources as well as the construction of the geothermal power plants in the Philippines is given. The cost and the viability of such plants under Philippine conditions are presented. The necessity of a planned development around the geothermal plant, such as heat-consuming industries, is stressed. 15 refs.

  16. A corrosivity classification system for geothermal resources

    SciTech Connect

    Conover, Marshall F.

    1982-10-08

    The most important difference between traditional steam systems and those that utilize geothermal fluids is the potential for corrosion of metals. The recently developed sourcebook ''Materials Selection Guidelines for Geothermal Energy Utilization Systems'' is expected to facilitate corrosion engineering decision making and reduce the cost of geothermal systems where new resources are similar to those presented by the corrosivity classification system.

  17. Geothermal Energy Development annual report 1979

    SciTech Connect

    Not Available

    1980-08-01

    This report is an exerpt from Earth Sciences Division Annual Report 1979 (LBL-10686). Progress in thirty-four research projects is reported including the following area: geothermal exploration technology, geothermal energy conversion technology, reservoir engineering, and geothermal environmental research. Separate entries were prepared for each project. (MHR)

  18. Geothermal energy for Hawaii: a prospectus

    SciTech Connect

    Yen, W.W.S.; Iacofano, D.S.

    1981-01-01

    An overview of geothermal development is provided for contributors and participants in the process: developers, the financial community, consultants, government officials, and the people of Hawaii. Geothermal energy is described along with the issues, programs, and initiatives examined to date. Hawaii's future options are explored. Included in appendices are: a technical glossary, legislation and regulations, a geothermal directory, and an annotated bibliography. (MHR)

  19. Geothermal progress monitor. Progress report No. 7

    SciTech Connect

    Not Available

    1983-04-01

    A state-by-state review of major geothermal-development activities during 1982 is presented. It also inlcudes a summary of recent drilling and exploration efforts and the results of the 1982 leasing program. Two complementary sections feature an update of geothermal direct-use applications and a site-by-site summary of US geothermal electric-power development.

  20. Strategic plan for the geothermal energy program

    SciTech Connect

    1998-06-01

    Geothermal energy (natural heat in the Earth`s crust) represents a truly enormous amount of energy. The heat content of domestic geothermal resources is estimated to be 70,000,000 quads, equivalent to a 750,000-year supply of energy for the entire Nation at current rates of consumption. World geothermal resources (exclusive of resources under the oceans) may be as much as 20 times larger than those of the US. While industry has focused on hydrothermal resources (those containing hot water and/or steam), the long-term future of geothermal energy lies in developing technology to enable use of the full range of geothermal resources. In the foreseeable future, heat may be extracted directly from very hot rocks or from molten rocks, if suitable technology can be developed. The US Department of Energy`s Office of Geothermal Technologies (OGT) endorses a vision of the future in which geothermal energy will be the preferred alternative to polluting energy sources. The mission of the Program is to work in partnership with US industry to establish geothermal energy as a sustainable, environmentally sound, economically competitive contributor to the US and world energy supply. In executing its mission and achieving its long-term vision for geothermal energy, the Program has identified five strategic goals: electric power generation; direct use applications and geothermal heat pumps; international geothermal development; science and technology; and future geothermal resources. This report discusses the objectives of these five goals.

  1. Small-scale Geothermal Power Plants Using Hot Spring Water

    NASA Astrophysics Data System (ADS)

    Tosha, T.; Osato, K.; Kiuchi, T.; Miida, H.; Okumura, T.; Nakashima, H.

    2013-12-01

    The installed capacity of the geothermal power plants has been summed up to be about 515MW in Japan. However, the electricity generated by the geothermal resources only contributes to 0.2% of the whole electricity supply. After the catastrophic earthquake and tsunami devastated the Pacific coast of north-eastern Japan on Friday, March 11, 2011, the Japanese government is encouraging the increase of the renewable energy supply including the geothermal. It needs, however, more than 10 years to construct the geothermal power plant with more than 10MW capacity since the commencement of the development. Adding the problem of the long lead time, high temperature fluid is mainly observed in the national parks and the high quality of the geothermal resources is limited. On the other hand hot springs are often found. The utilisation of the low temperature hot water becomes worthy of notice. The low temperature hot water is traditionally used for bathing and there are many hot springs in Japan. Some of the springs have enough temperature and enthalpy to turn the geothermal turbine but a new technology of the binary power generation makes the lower temp fluid to generate electricity. Large power generators with the binary technology are already installed in many geothermal fields in the world. In the recent days small-scale geothermal binary generators with several tens to hundreds kW capacity are developed, which are originally used by the waste heat energy in an iron factory and so on. The newly developed binary unit is compact suitable for the installation in a Japanese inn but there are the restrictions for the temperature of the hot water and the working fluid. The binary power unit using alternatives for chlorofluorocarbon as the working fluid is relatively free from the restriction. KOBELCO, a company of the Kobe Steel Group, designed and developed the binary power unit with an alternative for chlorofluorocarbon. The unit has a 70 MW class electric generator. Three

  2. Geothermal resource of Sumatra

    SciTech Connect

    Hochstein, M.P. . Geothermal Inst.); Sudarman, Sayogi . Geothermal Section)

    1993-06-01

    There are at least 30 high temperatures systems (with inferred reservoir temperatures > 200 C) along the active Sumatra Arc that transfer heat from crustal intrusions to the surface. These systems, together with eleven active volcanoes, five degassing volcanoes and one caldera volcano (Lake Toba), are controlled by the Sumatra Fault Zone, an active mega shear zone that follows the median axis of the arc. At least half of the active and degassing volcanoes are associated with volcanic geothermal reservoirs containing magmatic gases and acid fluids. Large, low temperature resources exist in the Tertiary sedimentary basins of east Sumatra (back-arc region), where anomalously higher thermal gradients (up to 8 C/100 m) have been measured. Volcanic activity was not continuous during the Cenozoic; subduction and arc volcanism probably decreased after the Eocene as a result of a clockwise rotation of Sumatra. In the Late Miocene, subduction started again, and andesitic volcanism reached a new peak of intensity in the Pliocene and has been continuous ever since. Rhyolitic volcanism, which has produced voluminous ignimbrite flows, began later (Pliocene/Pleistocene). All known rhyolitic centers associated with ignimbrite flows appear to lie along the Sumatra Fault Zone.

  3. Thermodynamics of geothermal fluids

    SciTech Connect

    Rogers, P.S.Z.

    1981-03-01

    A model to predict the thermodynamic properties of geothermal brines, based on a minimum amount of experimental data on a few key systems, is tested. Volumetric properties of aqueous sodium chloride, taken from the literature, are represented by a parametric equation over the range 0 to 300{sup 0}C and 1 bar to 1 kbar. Density measurements at 20 bar needed to complete the volumetric description also are presented. The pressure dependence of activity and thermal properties, derived from the volumetric equation, can be used to complete an equation of state for sodium chloride solutions. A flow calorimeter, used to obtain heat capacity data at high temperatures and pressures, is described. Heat capacity measurements, from 30 to 200{sup 0}C and 1 bar to 200 bar, are used to derive values for the activity coefficient and other thermodynamic properties of sodium sulfate solutions as a function of temperature. Literature data on the solubility of gypsum in mixed electrolyte solutions have been used to evaluate model parameters for calculating gypsum solubility in seawater and natural brines. Predictions of strontium and barium sulfate solubility in seawater also are given.

  4. Colorado Potential Geothermal Pathways

    DOE Data Explorer

    Zehner, Richard E.

    2012-02-01

    Citation Information: Originator: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Publication Date: 2012 Title: Colorado PRS Cool Fairways Edition: First Publication Information: Publication Place: Earth Science & Observation Center, Cooperative Institute for Research in Environmental Science (CIRES), University of Colorado, Boulder Publisher: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Description: This layer contains the weakened basement rocks. Isostatic gravity was utilized to identify structural basin areas, characterized by gravity low values reflecting weakened basement rocks. Together interpreted regional fault zones and basin outlines define geothermal "exploration fairways", where the potential exists for deep, superheated fluid flow in the absence of Pliocene or younger volcanic units Spatial Domain: Extent: Top: 4544698.569273 m Left: 144918.141004 m Right: 763728.391299 m Bottom: 4094070.397932 m Contact Information: Contact Organization: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Contact Person: Khalid Hussein Address: CIRES, Ekeley Building Earth Science & Observation Center (ESOC) 216 UCB City: Boulder State: CO Postal Code: 80309-0216 Country: USA Contact Telephone: 303-492-6782 Spatial Reference Information: Coordinate System: Universal Transverse Mercator (UTM) WGS’1984 Zone 13N False Easting: 500000.00000000 False Northing: 0.00000000 Central Meridian: -105.00000000 Scale Factor: 0.99960000 Latitude of Origin: 0.00000000 Linear Unit: Meter Datum: World Geodetic System ’1984 (WGS ’1984) Prime Meridian: Greenwich Angular Unit: Degree Digital Form: Format Name: Shape file

  5. Lassen geothermal system

    SciTech Connect

    Muffler, L.J.P.; Nehring, N.L.; Truesdell, A.H.; Janik, C.J.; Clynne, M.A.; Thompson, J.M.

    1982-01-01

    The Lassen geothermal system consists of a central vapor-dominated reservoir underlain by hot water that discharges peripherally at lower elevations. The major thermal upflow at Bumpass Hell (elevation 2500 m) displays numerour superheated fumaroles, one of which in 1976 was 159/sup 0/C. Gas geothermometers from the fumarole areas and water geothermometers from boiling Cl-bearing waters at Morgan Hot Springs (elevation 1530 m; 8 km south of Bumpass Hell) and from 176/sup 0/C waters in a well 12 km southeast of Bumpass Hell both indicate 230 to 240/sup 0/C for the deep thermal water. With increasing distance from Bumpass Hell, gases are progressively depleted in H/sub 2/S relative to CO/sub 2/ and N/sub 2/, owing to oxidation of H/sub 2/S to pyrite, sulfur, and sulfates and to dilution with atmospheric N/sub 2/. H/sub 2/O/gas ratios and degree of superheat of fumaroles can be explained by mixing of steam of maximum enthalpy (2804 J g/sup -1/) with near-surface water and with the condensate layer overlying the vapor-dominated reservoir.

  6. A structural model guide for geothermal exploration in Ancestral Mount Bao, Leyte, Philippines

    NASA Astrophysics Data System (ADS)

    Lagmay, Alfredo Mahar Francisco A.; Tengonciang, Arlene Mae P.; Marcos, Herbert V.; Pascua, Chelo S.

    2003-03-01

    The Tongonan Geothermal Field is the largest producing geothermal field in the Philippines having an installed capacity of 700 MW. It hosts several major power plants that tap geothermal power from the northern flank of the eroded Ancestral Mount Bao (AMB) volcano in Leyte Island, Philippines. A structural model guide is presented to delineate exploration targets in other flanks of the 1200 km 2 area of the AMB volcano. If applied, the model constrains the coverage of geothermal exploration to areas where more detailed investigations involving geological, geophysical, and geochemical methods can be conducted. Analog sand cone experiments and their comparison with the deformation of the AMB volcano were used to interpret wells within the Tongonan Geothermal Field. The study shows that existing producing wells in Tongonan straddle the crypto-Philippine fault, a N34°W (azimuth=326°) trending master fault inferred to traverse the base of the AMB volcano. This master fault induced fracture-controlled permeability where fluids in the Tongonan Geothermal Field circulate. The structural model suggests that the south-southeastern flank of the AMB directly above the southern extension of the master Philippine fault is an ideal geothermal target amenable to detailed exploration.

  7. Direct utilization of geothermal energy in western South Dakota agribusiness. Final report

    SciTech Connect

    Howard, S.M.

    1983-09-01

    This project involved the direct utilization of geothermal energy for (1) space heating of farm and ranch buildings, (2) drying grain, and (3) providing warm stock water during the winter. The site for this demonstration project was the Diamond Ring Ranch north of Midland, South Dakota. Geothermal water flowing from an existing well into the Madison Aquifer was used to heat four homes, a shop, a hospital barn for cattle, and air for a barn and grain dryer. This site is centrally located in the western region of South Dakota where geothermal water is available from the Madison Aquifer. The first year of the project involved the design of the heating systems and its construction while the following years were for operation, testing, demonstrating, and monitoring the system. Required modifications and improvements were made during this period. Operating modifications and improvements were made during this period. Operating experience showed that such application of geothermal resources is feasible and can result in substantial fuel savings. Economic analyses under a variety of assumptions generally gave payback periods of less than ten years. Numerous technical recommendations are made. The most significant being the necessity of passive protection from freezing of remote geothermal systems subject to winter shut downs caused by power or equipment failure. The primary institutional recommendation is to incorporate a use for the geothermal water such as irrigation or stock watering into agribusiness-related geothermal development.

  8. Environmental problems and geothermal permitting

    SciTech Connect

    Windrem, P.F.; Marr, G.L.

    1982-01-01

    This paper describes the stages of geothermal development, the attendant environmental hazards, and the jurisdictions of the various government agencies. Most examples of environmental hazards are drawn from the electric-power production in the geysers of northern California. The major enviromental effects of geothermal development are observed on air quality (including noise), land (including soil erosion, seismic activity and subsidence, wildlife habitat, and visual quality), and water quality. Ownership determines which agencies have jurisdiction, with the preparation of an environmental impact statement at the heart of the federal regulatory process and an environmental-impact report required at the state level. Environmental rules also cover power-plant construction and geothermal field abandonment. 58 references.

  9. Alternative Geothermal Power Production Scenarios

    DOE Data Explorer

    Sullivan, John

    2014-03-14

    The information given in this file pertains to Argonne LCAs of the plant cycle stage for a set of ten new geothermal scenario pairs, each comprised of a reference and improved case. These analyses were conducted to compare environmental performances among the scenarios and cases. The types of plants evaluated are hydrothermal binary and flash and Enhanced Geothermal Systems (EGS) binary and flash plants. Each scenario pair was developed by the LCOE group using GETEM as a way to identify plant operational and resource combinations that could reduce geothermal power plant LCOE values. Based on the specified plant and well field characteristics (plant type, capacity, capacity factor and lifetime, and well numbers and depths) for each case of each pair, Argonne generated a corresponding set of material to power ratios (MPRs) and greenhouse gas and fossil energy ratios.

  10. Geothermal district piping - A primer

    SciTech Connect

    Rafferty, K.

    1989-11-01

    Transmission and distribution piping constitutes approximately 40 -60% of the capital costs of typical geothermal district heating systems. Selections of economical piping suitable for the fluid chemistry is critical. Presently, most piping (56%) in geothermal systems is of asbestos cement construction. Some fiberglass (19%) and steel (19%) is also in use. Identification of an economical material to replace asbestos cement is important to future project development. By providing information on relative costs, purchase considerations, existing material performance and new products, this report seeks to provide a background of information to the potential pipe purchaser. A brief discussion of the use of uninsulated piping in geothermal district heating systems is also provided. 5 refs., 19 figs., 1 tab.

  11. Reliability computation from reliability block diagrams

    NASA Technical Reports Server (NTRS)

    Chelson, P. O.; Eckstein, R. E.

    1971-01-01

    A method and a computer program are presented to calculate probability of system success from an arbitrary reliability block diagram. The class of reliability block diagrams that can be handled include any active/standby combination of redundancy, and the computations include the effects of dormancy and switching in any standby redundancy. The mechanics of the program are based on an extension of the probability tree method of computing system probabilities.

  12. Geothermal energy projects - Planning and management

    SciTech Connect

    Goodman, L.J.; Love, R.N.

    1980-01-01

    A presentation is made of management requirements for the development of geothermal resources by citing three major, and successful, projects: the Wairakei geothermal power project of New Zealand, the Hawaii geothermal project of the United States, and the Tiwi geothermal project of the Philippines. The three case studies are presented according to a format in which the history of each project falls into four phases: (1) planning, appraisal and design (2) section, approval and activation (3) operation, control and handover and (4) evaluation and refinement. Each case study furnishes extensive performance and economic figures, along with consideration of such related issues as geothermal effluent chemical content, infrastructural requirements, and environmental impact.

  13. Geothermal Progress Monitor: Report No. 14

    SciTech Connect

    Not Available

    1992-12-01

    This issue of the Geothermal Progress Monitor, the 14th since its inception in 1980, highlights the anticipated rapid growth in the use of geothermal heat pumps and documents the continued growth in the use of geothermal energy for power generation, both in this country and abroad. In countries with a relatively large demand for new generation capacity, geothermal, if available, is being called on as a preferable alternative to the use of domestic or imported oil. On the other hand, in this country where current demand for new capacity is less, geothermal energy is commonly being put to use in small power generation units operating on the hot water resource.

  14. "Assistance to States on Geothermal Energy"

    SciTech Connect

    Linda Sikkema; Jennifer DeCesaro

    2006-07-10

    This final report summarizes work carried out under agreement with the U.S. Department of Energy, related to geothermal energy policy issues. This project has involved a combination of outreach and publications on geothermal energy—Contract Number DE-FG03-01SF22367—with a specific focus on educating state-level policymakers. Education of state policymakers is vitally important because state policy (in the form of incentives or regulation) is a crucial part of the success of geothermal energy. State policymakers wield a significant influence over all of these policies. They are also in need of high quality, non-biased educational resources which this project provided. This project provided outreach to legislatures, in the form of responses to information requests on geothermal energy and publications. The publications addressed: geothermal leasing, geothermal policy, constitutional and statutory authority for the development of geothermal district energy systems, and state regulation of geothermal district energy systems. These publications were distributed to legislative energy committee members, and chairs, legislative staff, legislative libraries, and other related state officials. The effect of this effort has been to provide an extensive resource of information about geothermal energy for state policymakers in a form that is useful to them. This non-partisan information has been used as state policymakers attempt to develop their own policy proposals related to geothermal energy in the states. Coordination with the National Geothermal Collaborative: NCSL worked and coordinated with the National Geothermal Collaborative (NGC) to ensure that state legislatures were represented in all aspects of the NGC's efforts. NCSL participated in NGC steering committee conference calls, attended and participated in NGC business meetings and reviewed publications for the NGC. Additionally, NCSL and WSUEP staff drafted a series of eight issue briefs published by the NGC

  15. Geothermal progress monitor report No. 6

    SciTech Connect

    Not Available

    1982-06-01

    Geothermal Progress Monitor Report No. 6 presents a state-by-state summary of the status of geothermal leasing, exploration, and development in major physiographic regions where geothermal resource potential has been identified. Recent state-specific activities are reported at the end of each state status report, while recent activities of a more general nature are summarized briefly in Part II of the report. A list of recent publications of potential interest to the geothermal community and a directory of contributors to the geothermal progress monitoring system are also included.

  16. Power electronics reliability analysis.

    SciTech Connect

    Smith, Mark A.; Atcitty, Stanley

    2009-12-01

    This report provides the DOE and industry with a general process for analyzing power electronics reliability. The analysis can help with understanding the main causes of failures, downtime, and cost and how to reduce them. One approach is to collect field maintenance data and use it directly to calculate reliability metrics related to each cause. Another approach is to model the functional structure of the equipment using a fault tree to derive system reliability from component reliability. Analysis of a fictitious device demonstrates the latter process. Optimization can use the resulting baseline model to decide how to improve reliability and/or lower costs. It is recommended that both electric utilities and equipment manufacturers make provisions to collect and share data in order to lay the groundwork for improving reliability into the future. Reliability analysis helps guide reliability improvements in hardware and software technology including condition monitoring and prognostics and health management.

  17. Human Reliability Program Overview

    SciTech Connect

    Bodin, Michael

    2012-09-25

    This presentation covers the high points of the Human Reliability Program, including certification/decertification, critical positions, due process, organizational structure, program components, personnel security, an overview of the US DOE reliability program, retirees and academia, and security program integration.

  18. Geothermal Reservoirs: Products of Cooling Plutons

    SciTech Connect

    Denis L. Norton

    2002-09-24

    The goals of this project were to develop an in depth understanding of how geothermal reservoirs form and elucidate those features that could potentially be useful in exploration and development of additional energy reserves. Collaboration with Jeff Hulen, EGI helped closely coordinate theoretical concepts and computational experiments with geologic reality in fulfillment of the tasks for this project. Initial reconnaissance computations with Tom Brikowski, University of Texas were critical in realizing the final products of this project. The products of this work contribute basic understanding of the dynamical conditions attendant to the formation of reservoirs in general and the Geysers reservoir in particular. The most exciting of the discoveries were a combination of mineralogical, computational, and geothermometric data sets that revealed a chaotic-like behavior of the processes is critical in the formation of reservoirs near cooling plutions. This discovery provides a fundamental basis for improving resource assessment and exploration methods for geothermal energy associated with very young magmas. Some of the main results are documented in scientific publications, and DOE progress reports. An additional publication is in preparation on the overall significance of fracture propagation and microseismic activity around young magmas.

  19. Fracturing operations in a dry geothermal reservoir

    SciTech Connect

    Rowley, J.C.; Hendron, R.H.; Nicholson, R.W.; Pettitt, R.A.; Sinclair, A.R.

    1983-10-01

    Fracturing and completing deep wells in hot, non-porous crystalline basement rock challenges conventional equipment use, procedures, and techniques common in oil and gas and normal geothermal completions. Fracturing operations at the Fenton Hill, New Mexico, Hot Dry Rock (HDR) Geothermal Test Site initiated unique developments necessary to solve problems caused by an extremely harsh downhole environment. Two deep wells were drilled to approximately 15,000 ft (4.6 km); formation temperatures are in excess of 600/sup 0/F (315/sup 0/C). The wells were drilled during 1979-1981, inclined at 35 degrees, one above the other, and directionally drilled in an azimuthal direction orthogonal to the least principal in-situ crustal stress field. The pair of wells form the injection and production wells of an energy extraction system which will be unique in reservoir development. Hydraulic fracturing experiments to connect the two wells have used openhole packers, hydraulic jet notching of the borehole wall, cemented-in isolation liners and casing packers. Problems were encountered with hole drag, high fracture gradients, H/sub 2/S in vent back fluids, stress corrosion cracking of tubulars, and the complex nature of three-dimensional fracture growth that requires very large volumes of injected water. Two fractured zones have been formed by hydraulic fracturing and defined by close-in, borehole deployed, microseismic detectors.

  20. Reliable Design Versus Trust

    NASA Technical Reports Server (NTRS)

    Berg, Melanie; LaBel, Kenneth A.

    2016-01-01

    This presentation focuses on reliability and trust for the users portion of the FPGA design flow. It is assumed that the manufacturer prior to hand-off to the user tests FPGA internal components. The objective is to present the challenges of creating reliable and trusted designs. The following will be addressed: What makes a design vulnerable to functional flaws (reliability) or attackers (trust)? What are the challenges for verifying a reliable design versus a trusted design?

  1. Geothermal activities in Central America

    SciTech Connect

    Whetten, J.T.; Hanold, R.J.

    1985-09-11

    The Agency for International Development is funding a new program in energy and minerals for Central America. Geothermal energy is an important component. A country-wide geothermal assessment has started in Honduras, and other assessment activities are in progress or planned for Costa Rica, El Salvador, Guatemala, and Panama. Instrumentation for well logging has been provided to Costa Rica, and a self-contained logging truck will be made available for use throughout Central America. An important objective of this program is to involve the private sector in resource development. 4 refs., 3 figs.

  2. BioSAXS Sample Changer: a robotic sample changer for rapid and reliable high-throughput X-ray solution scattering experiments

    SciTech Connect

    Round, Adam Felisaz, Franck; Fodinger, Lukas; Gobbo, Alexandre; Huet, Julien; Villard, Cyril; Blanchet, Clement E.; Roessle, Manfred; Svergun, Dmitri I.

    2015-01-01

    A robotic sample changer for solution X-ray scattering experiments optimized for speed and to use the minimum amount of material has been developed. This system is now in routine use at three high-brilliance European synchrotron sites, each capable of several hundred measurements per day. Small-angle X-ray scattering (SAXS) of macromolecules in solution is in increasing demand by an ever more diverse research community, both academic and industrial. To better serve user needs, and to allow automated and high-throughput operation, a sample changer (BioSAXS Sample Changer) that is able to perform unattended measurements of up to several hundred samples per day has been developed. The Sample Changer is able to handle and expose sample volumes of down to 5 µl with a measurement/cleaning cycle of under 1 min. The samples are stored in standard 96-well plates and the data are collected in a vacuum-mounted capillary with automated positioning of the solution in the X-ray beam. Fast and efficient capillary cleaning avoids cross-contamination and ensures reproducibility of the measurements. Independent temperature control for the well storage and for the measurement capillary allows the samples to be kept cool while still collecting data at physiological temperatures. The Sample Changer has been installed at three major third-generation synchrotrons: on the BM29 beamline at the European Synchrotron Radiation Facility (ESRF), the P12 beamline at the PETRA-III synchrotron (EMBL@PETRA-III) and the I22/B21 beamlines at Diamond Light Source, with the latter being the first commercial unit supplied by Bruker ASC.

  3. Predicting software reliability

    NASA Technical Reports Server (NTRS)

    Littlewood, B.

    1989-01-01

    A detailed look is given to software reliability techniques. A conceptual model of the failure process is examined, and some software reliability growth models are discussed. Problems for which no current solutions exist are addressed, emphasizing the very difficult problem of safety-critical systems for which the reliability requirements can be enormously demanding.

  4. Reliability model generator specification

    NASA Technical Reports Server (NTRS)

    Cohen, Gerald C.; Mccann, Catherine

    1990-01-01

    The Reliability Model Generator (RMG), a program which produces reliability models from block diagrams for ASSIST, the interface for the reliability evaluation tool SURE is described. An account is given of motivation for RMG and the implemented algorithms are discussed. The appendices contain the algorithms and two detailed traces of examples.

  5. Geothermal Project Data and Personnel Resumes

    SciTech Connect

    1980-01-01

    Rogers Engineering Co., Inc. is one of the original engineering companies in the US to become involved in geothermal well testing and design of geothermal power plants. Rogers geothermal energy development activities began almost twenty years ago with flow testing of the O'Neill well in Imperial Valley, California and well tests at Tiwi in the Philippines; a geothermal project for the Commission on Volcanology, Republic of the Philippines, and preparation of a feasibility study on the use of geothermal hot water for electric power generation at Casa Diablo, a geothermal area near Mammouth. This report has brief write-ups of recent geothermal resources development and power plant consulting engineering projects undertaken by Rogers in the US and abroad.

  6. Use of Geothermal Energy for Electric Power Generation

    SciTech Connect

    Mashaw, John M.; Prichett, III, Wilson

    1980-10-23

    The National Rural Electric Cooperative Association and its 1,000 member systems are involved in the research, development and utilization of many different types of supplemental and alternative energy resources. We share a strong commitment to the wise and efficient use of this country's energy resources as the ultimate answer to our national prosperity and economic growth. WRECA is indebted to the United States Department of Energy for funding the NRECA/DOE Geothermal Workshop which was held in San Diego, California in October, 1980. We would also like to express our gratitude to each of the workshop speakers who gave of their time, talent and experience so that rural electric systems in the Western U. S. might gain a clearer understanding of the geothermal potential in their individual service areas. The participants were also presented with practical, expert opinion regarding the financial and technical considerations of using geothermal energy for electric power production. The organizers of this conference and all of those involved in planning this forum are hopeful that it will serve as an impetus toward the full utilization of geothermal energy as an important ingredient in a more energy self-sufficient nation. The ultimate consumer of the rural electric system, the member-owner, expects the kind of leadership that solves the energy problems of tomorrow by fully utilizing the resources at our disposal today.

  7. Vapor mass ratio measurements in geothermal production wells

    SciTech Connect

    Dennis, B.R.; Kolar, J.D.; Lawton, R.G.

    1987-01-01

    Measurements in geothermal wellbores are very difficult because of the high-fluid pressures, high borehole temperatures, and limited data transmission links. Here the extraneous effects on transducers and associated signal conditioning are very difficult to eliminate and if not carefully controlled may be the only variables measured. All the effects of these severe environments are not found in textbooks but come primarily through experience. Calibration of all transducers and instruments under simulated environmental conditions is absolutely essential. All materials and equipment used in the instrumentation systems must be carefully chose, well understood and properly used. The time and effort spent in good planning and preparation will greatly increase the probability of meaningful data processing and prove to be much more efficient. The applications of conscientious calibration methodology together with applicable data analysis can result in very meaningful information concerning fluid flow in geothermal wells. Recently a number of geothermal production wells were logged using a high-temperature spinner/temperature/pressure (STP) tool developed under the Hot Dry Rock Geothermal Energy Program. To determine the thermodynamics state of the flowing wellbore fluid when the fluid can be in both the liquid and/or vapor state, absolute values of temperature and pressure are necessary. Consider, for example, the analysis of data obtained from one particular well, PGM-10, where the fluid flow was reported to be 21 kg/sec and the fluid temperatures at the surface was 240/sup 0/C.

  8. Geothermal Pumping and Induced Seismicity in Southern California Geothermal Fields

    NASA Astrophysics Data System (ADS)

    Weiser, D. A.; Jones, L.

    2013-12-01

    Induced earthquakes have been recognized for decades and observed in New Zealand, Switzerland, the US and elsewhere. Many factors can induce seismicity, including changes in pore pressure, temperature, volume, and chemistry. When fractured rock is injected with fluid, the effective normal stress and coefficient of friction are lowered and the rock is brought closer to failure. In this study, we examine the relationship between seismicity and geothermal pumping. We have obtained monthly injection and production data from the CA Department of Conservation for the Salton Sea Geothermal Field, Brawley Geothermal Field, and other California geothermal fields. We compare the temporal distribution of injection, production, fluid volume change (injection volume - production volume), and seismicity to determine if there are changes in the pumping rates that correspond to changes in seismicity rates. We observe a qualitative correlation between times of maximum fluid volume change and high seismicity levels, in particular, contemporaneous with the 2005 Obsidian Butte earthquake swarm. We also examine how changes in injection and production rates affect the Gutenberg-Richter b-value, earthquake depth, and focal mechanisms.

  9. Geothermal pipeline: Progress and development update, geothermal program monitor

    SciTech Connect

    1995-02-01

    This paper is a progress and development update describing three projects in the U.S. which involve the use of geothermal energy and ground-source heat pumps. The first project is located at Fort Polk Army Base in Louisiana. Four thousand government housing units are being retrofitted with efficient ground-soured near Bend, Oregon.

  10. Geothermal Program Review XII: proceedings. Geothermal Energy and the President's Climate Change Action Plan

    SciTech Connect

    Not Available

    1994-12-31

    Geothermal Program Review XII, sponsored by the Geothermal Division of US Department of Energy, was held April 25--28, 1994, in San Francisco, California. This annual conference is designed to promote effective technology transfer by bringing together DOE-sponsored researchers; utility representatives; geothermal energy developers; suppliers of geothermal goods and services; representatives from federal, state, and local agencies; and others with an interest in geothermal energy. In-depth reviews of the latest technological advancements and research results are presented during the conference with emphasis on those topics considered to have the greatest potential to impact the near-term commercial development of geothermal energy.

  11. Final Report, Testing and Sampling Procedures for Geothermal - Geopressed Wells

    SciTech Connect

    Boyd, W.E.; Dorfman, M.H.; Podio, A.L.

    1980-01-01

    Test wells to tap and sample geothermal-geopressured formations at 15,000-20,000 feet in the Gulf Coast area can be drilled routinely utilizing available equipment and methods. Electrical logs, surveys and fluid samplers can be used to obtain accurate and reliable information as to depths, temperatures, pressures, and fluid content of the geopressured formations before the well is completed. But it will be necessary to set casing and flow the well, at least temporarily, to secure fluid production volume and pressure data to evaluate the producibility of the geopressured resource. Electric logging and wireline survey methods are fully developed techniques for measuring the parameters needed to assess a geopressured zone before setting casing. Formation subsidence, though it may be slow to develop can be measured using radioactivity tracer surveys. The reports states three conclusions. (1) Existing well logging and surveying methods and equipment are generally satisfactory for testing and sampling and sampling a geothermal-geopressured resource. (2) No significant areas of research are needed to predict, detect, and evaluate geopressured formations for their potential as geothermal resources. (3) Static and dynamic testing procedures using existing technology are satisfactory to test, sample and analyze a geopressured reservoir. [DJE 2005

  12. Geothermal reservoir characterization through active thermal testing

    NASA Astrophysics Data System (ADS)

    Jung, Martin; Klepikova, Maria; Jalali, Mohammadreza; Fisch, Hansruedi; Loew, Simon; Amann, Florian

    2016-04-01

    Development and deployment of Enhanced Geothermal Systems (EGS) as renewable energy resources are part of the Swiss Energy Strategy 2050. To pioneer further EGS projects in Switzerland, a decameter-scale in-situ hydraulic stimulation and circulation (ISC) experiment has been launched at the Grimsel Test Site (GTS). The experiments are hosted in a low fracture density volume of the Grimsel granodiorite, similar to those expected at the potential enhanced geothermal system sites in the deep basement rocks of Northern Switzerland. One of the key goals of this multi-disciplinary experiment is to provide a pre- and post-stimulation characterization of the hydraulic and thermal properties of the stimulated fracture network with high resolution and to determine natural structures controlling the fluid flow and heat transport. Active thermal tests including thermal dilution tests and heat tracer tests allow for investigation of groundwater fluid flow and heat transport. Moreover, the spatial and temporal integrity of distributed temperature sensing (DTS) monitoring upgrades the potential and applicability of thermal tests in boreholes (e.g. Read et al., 2013). Here, we present active thermal test results and discuss the advantages and limitations of this method compared to classical approaches (hydraulic packer tests, solute tracer tests, flowing fluid electrical conductivity logging). The experimental tests were conducted in two boreholes intersected by a few low to moderately transmissive fault zones (fracture transmissivity of about 1E-9 m2/s - 1E-7 m2/s). Our preliminary results show that even in low-permeable environments active thermal testing may provide valuable insights into groundwater and heat transport pathways. Read T., O. Bour, V. Bense, T. Le Borgne, P. Goderniaux, M.V. Klepikova, R. Hochreutener, N. Lavenant, and V. Boschero (2013), Characterizing groundwater flow and heat transport in fractured rock using Fiber-Optic Distributed Temperature Sensing

  13. Seismic methods for resource exploration in enhanced geothermal systems

    SciTech Connect

    Gritto, Roland; Majer, Ernest L.

    2002-06-12

    A finite-difference modeling study of seismic wave propagation was conducted to determine how to best investigate subsurface faults and fracture zones in geothermal areas. The numerical model was created based on results from a previous seismic reflection experiment. A suite of fault models was investigated including blind faults and faults with surface expressions. The seismic data suggest that blind faults can be detected by a sudden attenuation of seismic wave amplitudes, as long the fault is located below the receiver array. Additionally, a conversion from P- to S-waves indicates the reflection and refraction of the P-waves while propagating across the fault. The drop in amplitudes and the excitation of S-waves can be used to estimate the location of the fault at depth. The accuracy of the numerical modeling depends on the availability of a priori in situ information (velocity and density) from borehole experiments in the geothermal area.

  14. Approach to reliability when applying new technologies

    NASA Technical Reports Server (NTRS)

    Bear, J. C.

    1981-01-01

    Tactical weapon systems, while different in many respects from PTTI applications, face similar risks in achieving reliability in development. General principles derived from experience in achieving high reliability in tactical weapon systems are selectively summarized for application to new technologies in unusual environments.

  15. Semiannual progress report for the Idaho Geothermal Program, April 1-September 30, 1979

    SciTech Connect

    Ihrig, R.R.

    1980-03-01

    Progress made by the Idaho Geothermal Program between March 31 and September 30, 1979 is discussed. Geothermal well tests at the Raft River geothermal site, facility construction, and the first hydraulic fracture treatment of a geothermal well are summarized. The results of direct applications experiments are described briefly, including experiments in aquaculture, agriculture, fluidized bed space heating, fluidized bed food drying, essential oil extraction, and geothermal assisted conversion of biomass to ethanol. Improvements to the binary cycle prototype power plant at Raft River, construction progress on the 5-MW pilot plant, and experimental work on direct contact heat exchangers are discussed. Also outlined is progress on environmental studies at Raft River, including a brief discussion of socioeconomic impacts of geothermal development on Cassia County, Idaho. Results are presented of a 48-industry survey conducted to determine industry's views of the technology barriers to accelerating hydrothermal energy commercialization. A projection summarizes the capital and manpower needed through 1987 to place 6800 MW of direct applications development online. Progress reports are also included on DOE's Program Opportunity Notice (PON) Program demonstration projects and DOE's Program Research and Development Announcement (PRDA) Program study projects.

  16. Semiannual progress report for the Idaho Geothermal Program, April 1 to September 30, 1980

    SciTech Connect

    Ihrig, R.R.

    1981-03-01

    The completion of the 5-MW Pilot Power Plant at the Raft River Geothermal Test Site, modification of the similar, binary cycle Prototype Power Plant, and the water treatment program that studies environmentally safe ways to inhibit corrosion and scaling in geothermal power plants and investigates corrosion resistant materials are summarized. Studies of binary geothermal cycles using mixed hydrocarbon working fluids are described as part of the continuing search for ways to produce low-cost electricity from moderate-temperature geothermal fluids. Progress is reported on studies of direct contact heat exchanger concepts, heat rejection systems, and primary heat exchangers with augmentation. As part of the now-ended series of aquaculture experiments, an unsuccessful attempt to incubate common carp embryos in geothermal waters is reported. An experiment in revegetating disturbed land at Raft River is mentioned and progress on DOE's new User Coupled Confirmation Drilling Program is described. An estimate is presented of the amount of hydrothermal energy that could be produced by the year 2000, with and without Federal assistance, for electric generation and direct applications such as industrial process heat. Progress is reported on the Marketing Assistance Program, through which technical information and assistance is provided potential users and developers of geothermal resources. Also reported is progress in DOE's Program Opportunity Notice (PON) Program demonstration projects and Program Research and Development Announcement (PRDA) Program study projects.

  17. Idealised modelling of ocean circulation driven by geothermal and hydrothermal fluxes at the seabed

    NASA Astrophysics Data System (ADS)

    Barnes, Jowan; Morales Maqueda, Miguel; Polton, Jeff

    2016-04-01

    There are two distinct processes by which heat is transferred from the solid Earth into the abyssal ocean. The first is conductive geothermal heating and the second is hydrothermal heating, involving advection of heated water from within the Earth's crust. Here, the noticeably different impacts of these two physical systems on ocean circulation are investigated. Previous modelling studies have applied geothermal heat fluxes at the seabed and shown discrepancies in circulation compared to cases which neglected heat from the Earth in their boundary conditions. The true heat flux in the ocean, however, is not entirely geothermal. From areas where the crust is younger a significant proportion of the heat input from the Earth could be in the form of fluid flow from hydrothermal vents, introducing forcing to the circulation which has previously been unaccounted for. In this study a set of idealised modelling experiments are run in order to investigate the effects of changing the balance of the total heat flux from purely geothermal to purely hydrothermal, via intermediate states in which the two boundary conditions are combined in different ratios. By performing such experiments it will be shown which of the two processes is dominant in its effects on circulation driven by heating at the seabed, and whether neglecting the hydrothermal advection in favour of a fully conductive geothermal boundary condition is justifiable. The results will inform the construction of boundary conditions for future circulation models involving ocean floor heat fluxes, specifically a regional study of geothermal and hydrothermal contributions within the Panama Basin.

  18. Geothermal Exploration Cost and Time

    DOE Data Explorer

    Jenne, Scott

    2013-02-13

    The Department of Energy’s Geothermal Technology Office (GTO) provides RD&D funding for geothermal exploration technologies with the goal of lowering the risks and costs of geothermal development and exploration. The National Renewable Energy Laboratory (NREL) was tasked with developing a metric in 2012 to measure the impacts of this RD&D funding on the cost and time required for exploration activities. The development of this cost and time metric included collecting cost and time data for exploration techniques, creating a baseline suite of exploration techniques to which future exploration cost and time improvements can be compared, and developing an online tool for graphically showing potential project impacts (all available at http://en.openei.org/wiki/Gateway: Geothermal). This paper describes the methodology used to define the baseline exploration suite of techniques (baseline), as well as the approach that was used to create the cost and time data set that populates the baseline. The resulting product, an online tool for measuring impact, and the aggregated cost and time data are available on the Open Energy Information website (OpenEI, http://en.openei.org) for public access. - Published 01/01/2013 by US National Renewable Energy Laboratory NREL.

  19. Leasing of federal geothermal resources

    NASA Technical Reports Server (NTRS)

    Stone, R. T.

    1974-01-01

    Pursuant to the Geothermal Steam Act of 1970 and the regulations published on December 21, 1973, the first Federal geothermal competitive lease sale was held on January 22, 1974, by the Department of the Interior, offering 33 tracts totalling over 50,000 acres in three Known Geothermal Resource Areas in California. On January 1, 1974, Federal lands outside Known Geothermal Resource Areas were opened to noncompetitive lease applications, of which, 3,763 had been received by June 1, 1974. During fiscal year 1974, a total of 22 competitive leases had been issued in California and Oregon. The principal components in the Department involved in the leasing program are the Geological Survey and the Bureau of Land Management. The former has jurisdiction over drilling and production operations and other activities in the immediate area of operations. The latter receives applications and issues leases and is responsible for managing leased lands under its jurisdiction outside the area of operations. The interrelationships of the above agencies and the procedures in the leasing program are discussed.

  20. Milk pasteurization with geothermal energy

    SciTech Connect

    Lund, J.W.

    1997-08-01

    Milk pasteurization with geothermal energy has been viewed by the author in two locations in the world: Klamath Falls, Oregon and Oradea, Romania. The former is not longer in operation; but, the latter has been operating since 1981. A third dairy using geothermal energy has been reported in Iceland which was established in 1930 to pasteurize milk and evaporate whey to produce brown whey cheese. This dairy merged with another co-op dairy in 1938 and was shut down. A description of the first two of these installations is deemed important, as there is potential for similar installation is deemed important, as there is potential for similar installation in other geothermal locations. These two reported savings in energy costs by using geothermal heat; the Klamath Falls installation producing 7,600 L/day (2,000 gals/day) for a savings of $12,000 per year and the Oradea plant producing 70,000 L/day (18,500 gals/day) (winter) and 200,000 L/day (52,800 gals/day) (summer) for savings of $120,000 per year (savings 800 TOE - tonnes of oil equivalent).

  1. Guide to Geothermal Heat Pumps

    SciTech Connect

    2011-02-01

    Geothermal heat pumps, also known as ground source heat pumps, geoexchange, water-source, earth-coupled, and earth energy heat pumps, take advantage of this resource and represent one of the most efficient and durable options on the market to heat and cool your home.

  2. Process for cementing geothermal wells

    DOEpatents

    Eilers, Louis H.

    1985-01-01

    A pumpable slurry of coal-filled furfuryl alcohol, furfural, and/or a low molecular weight mono- or copolymer thereof containing, preferably, a catalytic amount of a soluble acid catalyst is used to cement a casing in a geothermal well.

  3. Geothermal heat pumps in Pierre

    SciTech Connect

    Wegman, S.

    1997-12-01

    There are two municipal connected heat pumps in Pierre, South Dakota: the South Dakota Discovery Center and Pierre City Hall.Both systems now utilize plate heat exchanger between the city water loop and the building loop. This article describes the geothermal system used in Pierre for both space heating and cooling of municipal buildings.

  4. Coupling of hydrogeological models with hydrogeophysical data to characterize seawater intrusion and shallow geothermal systems

    NASA Astrophysics Data System (ADS)

    Beaujean, J.; Kemna, A.; Engesgaard, P. K.; Hermans, T.; Vandenbohede, A.; Nguyen, F.

    2013-12-01

    While coastal aquifers are being stressed due to climate changes and excessive groundwater withdrawals require characterizing efficiently seawater intrusion (SWI) dynamics, production of geothermal energy is increasingly being used to hinder global warming. To study these issues, we need both robust measuring technologies and reliable predictions based on numerical models. SWI models are currently calibrated using borehole observations. Similarly, geothermal models depend mainly on the temperature field at few locations. Electrical resistivity tomography (ERT) can be used to improve these models given its high sensitivity to TDS and temperature and its relatively high lateral resolution. Inherent geophysical limitations, such as the resolution loss, can affect the overall quality of the ERT images and also prevent the correct recovery of the desired hydrochemical property. We present an uncoupled and coupled hydrogeophysical inversion to calibrate SWI and thermohydrogeologic models using ERT. In the SWI models, we demonstrate with two synthetic benchmarks (homogeneous and heterogeneous coastal aquifers) the ability of cumulative sensitivity-filtered ERT images using surface-only data to recover the hydraulic conductivity. Filtering of ERT-derived data at depth, where resolution is poorer, and the model errors make the dispersivity more difficult to estimate. In the coupled approach, we showed that parameter estimation is significantly improved because regularization bias is replaced by forward modeling only. Our efforts are currently focusing on applying the uncoupled/coupled approaches on a real life case study using field data from the site of Almeria, SE Spain. In the thermohydrogeologic models, the most sensitive hydrologic parameters responsible for heat transport are estimated from surface ERT-derived temperatures and ERT resistance data. A real life geothermal experiment that took place on the Campus De Sterre of Ghent University, Belgium and a synthetic

  5. Direct-flash-steam geothermal-power-plant assessment. Final report

    SciTech Connect

    Alt, T.E.

    1982-01-01

    The objective of the project was to analyze the capacity and availability factors of an operating direct flash geothermal power plant. The analysis was to include consideration of system and component specifications, operating procedures, maintenance history, malfunctions, and outage rate. The plant studied was the 75 MW(e) geothermal power plant at Cerro Prieto, Mexico, for the years 1973 to 1979. To describe and assess the plant, the project staff reviewed documents, visited the plant, and met with staff of the operating utility. The high reliability and availability of the plant was documented and actions responsible for the good performance were identified and reported. The results are useful as guidance to US utilities considering use of hot water geothermal resources for power generation through a direct flash conversion cycle.

  6. Upgrading Amerada-type survey clocks for high-temperature geothermal service

    SciTech Connect

    Major, B.H.; Witten, C.L.

    1980-04-01

    The Amerada type subsurface recording gauges have been used by the oil and gas industry for many years. These mechanical logging instruments are currently used by the growing geothermal industry. As the gauges were designed for service in low-temperature oil and gas wells, a significant number of failures are occurring at elevated geothermal temperatures. The spring-driven mechanical survey clocks appear to be the primary cause of these failures. The clock mechanisms tend to stop or lock-up when exposed to temperatures as high as 300/sup 0/C. A project that was undertaken to upgrade the survey clocks to 300/sup 0/C capability is summarized. The major problems causing clock failure were determined and were rectified by minor modifications and lubrication of the moving parts. Several clocks so modified performed reliably, both during laboratory oven tests and during field tests performed in actual geothermal wells at temperatures up to 330/sup 0/C.

  7. Hawaii Energy Resource Overviews. Volume 1. Potential noise issues with geothermal development in Hawaii

    SciTech Connect

    Burgess, J.C.

    1980-06-01

    This report concerns primarily the environmental noise expected to arise from construction and operation at HGP-A. A brief discussion of expected noise effects if the geothermal field is developed is included. Some of this discussion is applicable to noise problems that may arise if other geothermal fields are found and developed, but site-specific discussion of other fields can be formulated only when exact locations are identified. There is information concerning noise at other geothermal fields, especially the Geysers. This report includes only second-hand references to such information. No measurements of ambient sound levels near the HGP-A are available, no reliable and carefully checked sound level measurements from the HGP-A well operation are available.

  8. DOE Webinar - Residential Geothermal Heat Pump Retrofits (Presentation)

    SciTech Connect

    Anderson, E. R.

    2010-12-14

    This presentation was given December 14, 2010, as part of DOE's Webinar series. The presentation discusses geothermal heat pump retrofits, technology options, and an overview of geothermal energy and geothermal heat pumps.

  9. Geothermal Technologies Program - Geothermal Energy: Putting Creative Ideas to Work (Green Jobs)

    SciTech Connect

    2010-06-01

    Rapid expansion of U.S. geothermal capacity is opening new job opportunities across the nation. With more than 3,000 megawatts (MW) already installed, the United States leads the world in existing geothermal capacity.

  10. National Geothermal Data System (NGDS) Geothermal Data: Community Requirements and Information Engineering

    SciTech Connect

    Anderson, Arlene; Blackwell, David; Chickering, Cathy; Boyd, Toni; Horne, Roland; MacKenzie, Matthew; Moore, Joseph; Nickull, Duane; Richard, Stephen; Shevenell, Lisa A.

    2013-10-01

    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 investing in the development of the National Geothermal Data System (NGDS). This paper outlines efforts among geothermal data providers nationwide to supply cutting edge geo-informatics. NGDS geothermal data acquisition, delivery, and methodology are discussed. In particular, this paper addresses the various types of data required to effectively assess geothermal energy potential and why simple links to existing data are insufficient. To create a platform for ready access by all geothermal stakeholders, the NGDS includes a work plan that addresses data assets and resources of interest to users, a survey of data providers, data content models, and how data will be exchanged and promoted, as well as lessons learned within the geothermal community.

  11. Water Resource Assessment of Geothermal Resources and Water Use in Geopressured Geothermal Systems

    SciTech Connect

    Clark, C. E.; Harto, C. B.; Troppe, W. A.

    2011-09-01

    This technical report from Argonne National Laboratory presents an assessment of fresh water demand for future growth in utility-scale geothermal power generation and an analysis of fresh water use in low-temperature geopressured geothermal power generation systems.

  12. Low-Temperature Geothermal Resources, Geothermal Technologies Program (GTP) (Fact Sheet)

    SciTech Connect

    Not Available

    2010-05-01

    This document highlights the applications of low-temperature geothermal resources and the potential for future uses as well as current Geothermal Technologies Program-funded projects related to low-temperature resources.

  13. GEOTHERMAL ENVIRONMENTAL IMPACT ASSESSMENT: GROUND WATER MONITORING GUIDELINES FOR GEOTHERMAL DEVELOPMENT

    EPA Science Inventory

    This report discusses potential ground water pollution from geothermal resource development, conversion, and waste disposal, and proposes guidelines for developing a ground water monitoring plan for any such development. Geothermal processes, borehole logging, and injection well ...

  14. Human reliability analysis

    SciTech Connect

    Dougherty, E.M.; Fragola, J.R.

    1988-01-01

    The authors present a treatment of human reliability analysis incorporating an introduction to probabilistic risk assessment for nuclear power generating stations. They treat the subject according to the framework established for general systems theory. Draws upon reliability analysis, psychology, human factors engineering, and statistics, integrating elements of these fields within a systems framework. Provides a history of human reliability analysis, and includes examples of the application of the systems approach.

  15. Geothermal energy from deep sedimentary basins: The Valley of Mexico (Central Mexico)

    NASA Astrophysics Data System (ADS)

    Lenhardt, Nils; Götz, Annette E.

    2015-04-01

    The geothermal potential of the Valley of Mexico has not been addressed in the past, although volcaniclastic settings in other parts of the world contain promising target reservoir formations. A first assessment of the geothermal potential of the Valley of Mexico is based on thermophysical data gained from outcrop analogues, covering all lithofacies types, and evaluation of groundwater temperature and heat flow values from literature. Furthermore, the volumetric approach of Muffler and Cataldi (1978) leads to a first estimation of ca. 4000 TWh (14.4 EJ) of power generation from Neogene volcanic rocks within the Valley of Mexico. Comparison with data from other sedimentary basins where deep geothermal reservoirs are identified shows the high potential of the Valley of Mexico for future geothermal reservoir utilization. The mainly low permeable lithotypes may be operated as stimulated systems, depending on the fracture porosity in the deeper subsurface. In some areas also auto-convective thermal water circulation might be expected and direct heat use without artificial stimulation becomes reasonable. Thermophysical properties of tuffs and siliciclastic rocks qualify them as promising target horizons (Lenhardt and Götz, 2015). The here presented data serve to identify exploration areas and are valuable attributes for reservoir modelling, contributing to (1) a reliable reservoir prognosis, (2) the decision of potential reservoir stimulation, and (3) the planning of long-term efficient reservoir utilization. References Lenhardt, N., Götz, A.E., 2015. Geothermal reservoir potential of volcaniclastic settings: The Valley of Mexico, Central Mexico. Renewable Energy. [in press] Muffler, P., Cataldi, R., 1978. Methods for regional assessment of geothermal resources. Geothermics, 7, 53-89.

  16. Geothermal pipeline: Progress and development update from the geothermal progress monitor

    SciTech Connect

    1994-07-01

    This article is a progress and development update of new prospects for the utilization of geothermal energy. The city of San Bernadino, California uses high-quality geothermal fluids for laundry processes without the need for water softening or heating. Four geothermal prospects in Oregon including exploration work by Amadarko, CE Exploration Company, Trans-Pacific Geothermal Corporation, and Vulcan Power Company are also reviewed.

  17. Proceedings of a Topical Meeting On Small Scale Geothermal Power Plants and Geothermal Power Plant Projects

    SciTech Connect

    1986-02-12

    These proceedings describe the workshop of the Topical Meeting on Small Scale Geothermal Power Plants and Geothermal Power Plant Projects. The projects covered include binary power plants, rotary separator, screw expander power plants, modular wellhead power plants, inflow turbines, and the EPRI hybrid power system. Active projects versus geothermal power projects were described. In addition, a simple approach to estimating effects of fluid deliverability on geothermal power cost is described starting on page 119. (DJE-2005)

  18. Geothermal Energy Technology: a current-awareness bulletin

    SciTech Connect

    Smith, L.B.

    1983-01-15

    This bulletin announces on a semimonthly basis the current worldwide information available on the technology required for economic recovery of geothermal energy and its use either directly or for production of electric power. The subject content encompasses: resource status and assessment, geology and hydrology of geothermal systems, geothermal exploration, legal and institutional aspects, economic and final aspects, environmental aspects and waste disposal, by-products, geothermal power plants, geothermal engineering, direct energy utilization, and geothermal data and theory.

  19. Recalibrating software reliability models

    NASA Technical Reports Server (NTRS)

    Brocklehurst, Sarah; Chan, P. Y.; Littlewood, Bev; Snell, John

    1989-01-01

    In spite of much research effort, there is no universally applicable software reliability growth model which can be trusted to give accurate predictions of reliability in all circumstances. Further, it is not even possible to decide a priori which of the many models is most suitable in a particular context. In an attempt to resolve this problem, techniques were developed whereby, for each program, the accuracy of various models can be analyzed. A user is thus enabled to select that model which is giving the most accurate reliability predictions for the particular program under examination. One of these ways of analyzing predictive accuracy, called the u-plot, in fact allows a user to estimate the relationship between the predicted reliability and the true reliability. It is shown how this can be used to improve reliability predictions in a completely general way by a process of recalibration. Simulation results show that the technique gives improved reliability predictions in a large proportion of cases. However, a user does not need to trust the efficacy of recalibration, since the new reliability estimates produced by the technique are truly predictive and so their accuracy in a particular application can be judged using the earlier methods. The generality of this approach would therefore suggest that it be applied as a matter of course whenever a software reliability model is used.

  20. Software Reliability 2002

    NASA Technical Reports Server (NTRS)

    Wallace, Dolores R.

    2003-01-01

    In FY01 we learned that hardware reliability models need substantial changes to account for differences in software, thus making software reliability measurements more effective, accurate, and easier to apply. These reliability models are generally based on familiar distributions or parametric methods. An obvious question is 'What new statistical and probability models can be developed using non-parametric and distribution-free methods instead of the traditional parametric method?" Two approaches to software reliability engineering appear somewhat promising. The first study, begin in FY01, is based in hardware reliability, a very well established science that has many aspects that can be applied to software. This research effort has investigated mathematical aspects of hardware reliability and has identified those applicable to software. Currently the research effort is applying and testing these approaches to software reliability measurement, These parametric models require much project data that may be difficult to apply and interpret. Projects at GSFC are often complex in both technology and schedules. Assessing and estimating reliability of the final system is extremely difficult when various subsystems are tested and completed long before others. Parametric and distribution free techniques may offer a new and accurate way of modeling failure time and other project data to provide earlier and more accurate estimates of system reliability.

  1. Recalibrating software reliability models

    NASA Technical Reports Server (NTRS)

    Brocklehurst, Sarah; Chan, P. Y.; Littlewood, Bev; Snell, John

    1990-01-01

    In spite of much research effort, there is no universally applicable software reliability growth model which can be trusted to give accurate predictions of reliability in all circumstances. Further, it is not even possible to decide a priori which of the many models is most suitable in a particular context. In an attempt to resolve this problem, techniques were developed whereby, for each program, the accuracy of various models can be analyzed. A user is thus enabled to select that model which is giving the most accurate reliability predicitons for the particular program under examination. One of these ways of analyzing predictive accuracy, called the u-plot, in fact allows a user to estimate the relationship between the predicted reliability and the true reliability. It is shown how this can be used to improve reliability predictions in a completely general way by a process of recalibration. Simulation results show that the technique gives improved reliability predictions in a large proportion of cases. However, a user does not need to trust the efficacy of recalibration, since the new reliability estimates prodcued by the technique are truly predictive and so their accuracy in a particular application can be judged using the earlier methods. The generality of this approach would therefore suggest that it be applied as a matter of course whenever a software reliability model is used.

  2. Reliability of fluid systems

    NASA Astrophysics Data System (ADS)

    Kopáček, Jaroslav; Fojtášek, Kamil; Dvořák, Lukáš

    2016-03-01

    This paper focuses on the importance of detection reliability, especially in complex fluid systems for demanding production technology. The initial criterion for assessing the reliability is the failure of object (element), which is seen as a random variable and their data (values) can be processed using by the mathematical methods of theory probability and statistics. They are defined the basic indicators of reliability and their applications in calculations of serial, parallel and backed-up systems. For illustration, there are calculation examples of indicators of reliability for various elements of the system and for the selected pneumatic circuit.

  3. The Reliability of Psychiatric Diagnosis Revisited

    PubMed Central

    Rankin, Eric; France, Cheryl; El-Missiry, Ahmed; John, Collin

    2006-01-01

    Background: The authors reviewed the topic of reliability of psychiatric diagnosis from the turn of the 20th century to present. The objectives of this paper are to explore the reasons of unreliability of psychiatric diagnosis and propose ways to improve the reliability of psychiatric diagnosis. Method: The authors reviewed the literature on the concept of reliability of psychiatric diagnosis with emphasis on the impact of interviewing skills, use of diagnostic criteria, and structured interviews on the reliability of psychiatric diagnosis. Results: Causes of diagnostic unreliability are attributed to the patient, the clinician and psychiatric nomenclature. The reliability of psychiatric diagnosis can be enhanced by using diagnostic criteria, defining psychiatric symptoms and structuring the interviews. Conclusions: The authors propose the acronym ‘DR.SED,' which stands for diagnostic criteria, reference definitions, structuring the interview, clinical experience, and data. The authors recommend that clinicians use the DR.SED paradigm to improve the reliability of psychiatric diagnoses. PMID:21103149

  4. Relating design and environmental variables to reliability

    NASA Astrophysics Data System (ADS)

    Kolarik, William J.; Landers, Thomas L.

    The combination of space application and nuclear power source demands high reliability hardware. The possibilities of failure, either an inability to provide power or a catastrophic accident, must be minimized. Nuclear power experiences on the ground have led to highly sophisticated probabilistic risk assessment procedures, most of which require quantitative information to adequately assess such risks. In the area of hardware risk analysis, reliability information plays a key role. One of the lessons learned from the Three Mile Island experience is that thorough analyses of critical components are essential. Nuclear grade equipment shows some reliability advantages over commercial. However, no statistically significant difference has been found. A recent study pertaining to spacecraft electronics reliability, examined some 2500 malfunctions on more than 300 aircraft. The study classified the equipment failures into seven general categories. Design deficiencies and lack of environmental protection accounted for about half of all failures. Within each class, limited reliability modeling was performed using a Weibull failure model.

  5. Geothermal demonstration: Zunil food dehydration facility

    SciTech Connect

    Maldonado, O. ); Altseimer, J.; Thayer, G.R. ); Cooper, L. ); Caicedo, A. . Inst. Nacional de Electrificacion)

    1991-08-01

    A food dehydration facility was constructed near the town of Zunil, Guatemala, to demonstrate the use of geothermal energy for industrial applications. The facility, with some modifications to the design, was found to work quite satisfactorily. Tests using five different products were completed during the time geothermal energy was used in the plant. During the time the plant was not able to use geothermal energy, a temporary diesel-fueled boiler provided the energy to test dehydration on seven other crops available in this area. The system demonstrates that geothermal heat can be used successfully for dehydrating food products. Many other industrial applications of geothermal energy could be considered for Zunil since a considerable amount of moderate-temperature heat will become available when the planned geothermal electrical facility is constructed there. 6 refs., 15 figs., 7 tabs.

  6. Direct contact, binary fluid geothermal boiler

    DOEpatents

    Rapier, P.M.

    1979-12-27

    Energy is extracted from geothermal brines by direct contact with a working fluid such as isobutane which is immiscible with the brine in a geothermal boiler. The geothermal boiler provides a distributor arrangement which efficiently contacts geothermal brine with the isobutane in order to prevent the entrainment of geothermal brine in the isobutane vapor which is directed to a turbine. Accordingly the problem of brine carryover through the turbine causing corrosion and scaling thereof is eliminated. Additionally the heat exchanger includes straightening vanes for preventing startup and other temporary fluctuations in the transitional zone of the boiler from causing brine carryover into the turbine. Also a screen is provided in the heat exchanger to coalesce the working fluid and to assist in defining the location of the transitional zone where the geothermal brine and the isobutane are initially mixed.

  7. Direct contact, binary fluid geothermal boiler

    DOEpatents

    Rapier, Pascal M.

    1982-01-01

    Energy is extracted from geothermal brines by direct contact with a working fluid such as isobutane which is immiscible with the brine in a geothermal boiler. The geothermal boiler provides a distributor arrangement which efficiently contacts geothermal brine with the isobutane in order to prevent the entrainment of geothermal brine in the isobutane vapor which is directed to a turbine. Accordingly the problem of brine carry-over through the turbine causes corrosion and scaling thereof is eliminated. Additionally the heat exchanger includes straightening vanes for preventing startup and other temporary fluctuations in the transitional zone of the boiler from causing brine carryover into the turbine. Also a screen is provided in the heat exchanger to coalesce the working fluid and to assist in defining the location of the transitional zone where the geothermal brine and the isobutane are initially mixed.

  8. The National Geothermal Energy Research Program

    NASA Technical Reports Server (NTRS)

    Green, R. J.

    1974-01-01

    The continuous demand for energy and the concern for shortages of conventional energy resources have spurred the nation to consider alternate energy resources, such as geothermal. Although significant growth in the one natural steam field located in the United States has occurred, a major effort is now needed if geothermal energy, in its several forms, is to contribute to the nation's energy supplies. From the early informal efforts of an Interagency Panel for Geothermal Energy Research, a 5-year Federal program has evolved whose objective is the rapid development of a commercial industry for the utilization of geothermal resources for electric power production and other products. The Federal program seeks to evaluate the realistic potential of geothermal energy, to support the necessary research and technology needed to demonstrate the economic and environmental feasibility of the several types of geothermal resources, and to address the legal and institutional problems concerned in the stimulation and regulation of this new industry.

  9. Geothermal fracture stimulation technology. Volume III. Geothermal fracture fluids

    SciTech Connect

    Not Available

    1981-01-01

    A detailed study of all available and experimental frac fluid systems is presented. They have been examined and tested for physical properties that are important in the stimulation of hot water geothermal wells. These fluids consist of water-based systems containing high molecular weight polymers in the uncrosslinked and crosslinked state. The results of fluid testing for many systems are summarized specifically at geothermal conditions or until breakdown occurs. Some of the standard tests are ambient viscosity, static aging, high temperature viscosity, fluid-loss testing, and falling ball viscosity at elevated temperatures and pressures. Results of these tests show that unalterable breakdown of the polymer solutions begins above 300/sup 0/F. This continues at higher temperatures with time even if stabilizers or other high temperature additives are included.

  10. Geothermal energy development in the eastern United States. Papers presented: Geothermal Resources Council Annual Meeting

    NASA Astrophysics Data System (ADS)

    1980-10-01

    Topic areas covered include: technical assistance (hydrothermal resource application in the eastern United States); GRITS - a computer model for economic evaluation of direct-uses of geothermal energy; geothermal market penetration in the residential sector - capital stock impediments and compensatory incentives; an analysis of benefits and costs of accelerated market penetration by a geothermal community heating system.

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

    SciTech Connect

    McLarty, Lynn; Entingh, Daniel

    2000-09-29

    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.

  12. Geothermal energy: tomorrow's alternative today. A handbook for geothermal-energy development in Delaware

    SciTech Connect

    Mancus, J.; Perrone, E.

    1982-08-01

    This is a general procedure guide to various technical, economic, and institutional aspects of geothermal development in Delaware. The following are covered: geothermal as an alternative, resource characteristics, geology, well mechanics and pumping systems, fluid disposal, direct heat utilization-feasibility, environmental and legal issues, permits and regulations, finance and taxation, and steps necessary for geothermal development. (MHR)

  13. Materials for Geothermal Production

    SciTech Connect

    Kukacka, Lawrence E.

    1992-03-24

    Advances in the development of new materials continue to be made in the Geothermal Materials Project. Many successes have already been accrued and the results used commercially. In FY 1991, work was focused on reducing well drilling, fluid transport and energy conversion costs. Specific activities performed included lightweight CO{sub 2}-resistant well cements, thermally conductive and scale resistant protective liner systems, chemical systems for lost circulation control, corrosion mitigation in process components at The Geysers, and elastomer-metal bonding systems. Efforts to transfer the technologies developed in these efforts to other energy-related sectors of the economy continued and considerable success was achieved. Laboratory testing of BNL-developed phosphate modified calcium aluminate cements confirmed their hydrolytic stability in 300 C brine and their resistance to chemical attack by CO{sub 2}. Specimens were found to be >20 times more resistant to carbonation than Class H cement and twice as resistant as unmodified calcium aluminate cements. Testing of thermally conductive polymer cements as potential corrosion resistant liner materials for use in heat exchanger applications was continued. Field test were conducted in flowing hypersaline brine and the results indicated scale deposition rates lower than those on a high alloy steel. Additional tests for bottoming cycle heat exchange use are planned for FY 1992. Progress was also made with chemical systems for lost circulation control. If materials placement is to be performed by pumping through an open drillpipe or through a drillable straddle packer, a bentonite-ammonium polyphosphate-borax-magnesium oxide formulation, containing fibers or particulates when large fissures are encountered, can be used. This system was ready for demonstration in FY 1991, but a suitable test site did not become available. Optimization of this and three other formulations for use with other Sandia National Laboratories

  14. Geothermal development in the Pacific rim. Transactions, Volume 20

    SciTech Connect

    1996-12-31

    This document entitled Geothermal Development in the Pacific Rim contains the Transactions, Volume 20 of the Geothermal Resources Council, 1996 Annual Meeting. Topics of the presentations include: Air quality assessment and mitigation, District heating and other direct-uses of geothermal energy, Environmental permitting in the Pacific Rim, Geothermal exploration strategies, tools and techniques, and Focus of IEA Geothermal programs. Geothermal resources and resource development in the USA, Indonesia, Mexico, Japan, and the Philippines are highlighted. Also included is a section on Geothermal power plant design, construction, and operation, and Geothermal reservoir assessment, the key to international financing.

  15. Geothermal programs at Lawrence Livermore National Laboratory

    SciTech Connect

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

    1987-07-10

    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.

  16. The LBL geothermal reservoir technology program

    SciTech Connect

    Lippmann, M.J.

    1991-03-01

    The main objective of the DOE/GD-funded Geothermal Reservoir Technology Program at Lawrence Berkeley Laboratory is the development and testing of new and improved methods and tools needed by industry in its effort to delineate, characterize, evaluate, and exploit hydrothermal systems for geothermal energy. This paper summarizes the recent and ongoing field, laboratory, and theoretical research activities being conducted as part of the Geothermal Reservoir Technology Program. 28 refs., 4 figs.

  17. Geothermal drilling research in the United States

    SciTech Connect

    Varnado, S.G.; Maish, A.B.

    1980-01-01

    The high cost of drilling and completing geothermal wells is an impediment to the development of this resource. The Department of Energy (DOE), Division of Geothermal Energy (DGE), is conducting an R and D program directed at reducing well costs through improvements in geothermal drilling and completion technology. This program includes R and D activities in high temperature drilling hardware, drilling fluids, lost circulation control methods, completion technology, and advanced drilling systems. An overview of the program is presented.

  18. The geothermal program at Lawrence Berkeley Laboratory

    SciTech Connect

    Lippmann, M.J.

    1987-06-01

    The main purpose of the geothermal program at Lawrence Berkeley Laboratory is to develop, improve and validate methods and instrumentation to: (1) determine geothermal reservoir parameters; (2) detect and characterize reservoir fractures and boundaries; and (3) identify and evaluate the importance of reservoir processes. The ultimate objective of the program, which includes field, theoretical and modeling activities, is to advance the state-of-the-art for characterizing geothermal systems and evaluating their productive capacity and longevity under commercial exploitation.

  19. Plant support capabilities of a geothermal fluid

    SciTech Connect

    Robinson, F.E.; Singh, K.; Berry, W.; Thomas, T.R.

    1980-09-01

    Geothermal fluids and shallow groundwater from Republic Geothermal, Inc. lease area of East Mesa in Imperial County, California were used successfully to irrigate sugar beet, alfalfa, asparagus, date palm, tamarisk, and desert climax vegetation. Chemical characteristics of the two irrigation fluids differed, but total dissolved solids content of the fluids were similar and within the 2000 mg/l range. The geothermal fluid contains elements which could be harmful to irrigated plants or plant consumers.

  20. Midland, South Dakota geothermal district heating

    SciTech Connect

    Lund, J.W.

    1997-12-01

    This article describes historical aspects and present usage of geothermal district heating systems in the town of Midland, South Dakota. The use of geothermal resources exists due to a joint venture between the school district and the city back in the early 1960`s. A total of approximately 30,000 square feet (2800 square meters) of floor space is heated using geothermal energy in Midland. This provides an estimated annual saving in propane cost of $15,000 to the community.

  1. Geothermal Research and Development Program. Quarterly technical report, September--December 1992

    SciTech Connect

    Not Available

    1993-01-25

    Results are reported on adsorption of water vapor on reservoir rocks, physics of injection of water into vapor-dominated geothermal reservoirs, earth-tide effects on downhole pressures, injection optimization at the Geysers, effects of salinity in adsorption experiments, interpreting multiwell pressure data from Ohaaki, and estimation of adsorption parameters from transient experiments.

  2. Method to Recover Media Ligand Losses During Sorption of Rare Earth Elements from Simulated Geothermal Brines

    DOE Data Explorer

    Dean Stull

    2016-05-24

    This document describes the method and results of an in-situ experiment used to confirm that ligand bleed from a sorptive media can be contained. The experiment focused on maintaining the media's sorption of rare earth elements (REE) obtained from a simulated geothermal brine doped with known mineral concentrations.

  3. A method for temperature estimation in high-temperature geothermal reservoirs by using synthetic fluid inclusions

    NASA Astrophysics Data System (ADS)

    Ruggieri, Giovanni; Orlando, Andrea; Chiarantini, Laura; Borrini, Daniele; Weisenberger, Tobias B.

    2016-04-01

    Super-hot geothermal systems in magmatic areas are a possible target for the future geothermal exploration either for the direct exploitation of fluids or as a potential reservoirs of Enhanced Geothermal Systems. Reservoir temperature measurements are crucial for the assessment of the geothermal resources, however temperature determination in the high-temperature (>380°C) zone of super-hot geothermal systems is difficult or impossible by using either mechanical temperature and pressure gauges (Kuster device) and electronic devices. In the framework of Integrated Methods for Advanced Geothermal Exploration (IMAGE) project, we developed a method to measure high reservoir temperature by the production of synthetic fluid inclusions within an apparatus that will be placed in the high-temperature zone of geothermal wells. First experiments were carried out by placing a gold capsule containing pre-fractured quartz and an aqueous solution (10 wt.% NaCl + 0.4 wt.% NaOH) in an externally heated pressure vessel. Experimental pressure-temperature conditions (i.e. 80-300 bars and 280-400°C) were set close to the liquid/vapour curve of pure H2O or along the H2O critical isochore. The experiments showed that synthetic fluid inclusions form within a relatively short time (even in 48 hours) and that temperatures calculated from homogenization temperatures and isochores of newly formed inclusions are close to experimental temperatures. A second set of laboratory experiments were carried out by using a stainless steel micro-rector in which a gold capsule (containing the pre-fractured quartz and the aqueous solution) was inserted together with an amount of distilled water corresponding to the critical density of water. These experiments were conducted by leaving the new micro-reactor within a furnace at 400°C and were aimed to reproduce the temperature existing in super-hot geothermal wells. Synthetic fluid inclusions formed during the experiments had trapping temperature

  4. Uncertainty analysis of geothermal energy economics

    NASA Astrophysics Data System (ADS)

    Sener, Adil Caner

    This dissertation research endeavors to explore geothermal energy economics by assessing and quantifying the uncertainties associated with the nature of geothermal energy and energy investments overall. The study introduces a stochastic geothermal cost model and a valuation approach for different geothermal power plant development scenarios. The Monte Carlo simulation technique is employed to obtain probability distributions of geothermal energy development costs and project net present values. In the study a stochastic cost model with incorporated dependence structure is defined and compared with the model where random variables are modeled as independent inputs. One of the goals of the study is to attempt to shed light on the long-standing modeling problem of dependence modeling between random input variables. The dependence between random input variables will be modeled by employing the method of copulas. The study focuses on four main types of geothermal power generation technologies and introduces a stochastic levelized cost model for each technology. Moreover, we also compare the levelized costs of natural gas combined cycle and coal-fired power plants with geothermal power plants. The input data used in the model relies on the cost data recently reported by government agencies and non-profit organizations, such as the Department of Energy, National Laboratories, California Energy Commission and Geothermal Energy Association. The second part of the study introduces the stochastic discounted cash flow valuation model for the geothermal technologies analyzed in the first phase. In this phase of the study, the Integrated Planning Model (IPM) software was used to forecast the revenue streams of geothermal assets under different price and regulation scenarios. These results are then combined to create a stochastic revenue forecast of the power plants. The uncertainties in gas prices and environmental regulations will be modeled and their potential impacts will be

  5. Low-temperature geothermal resources of Washington

    SciTech Connect

    Schuster, J.E. ); Bloomquist, R.G. )

    1994-11-01

    USDOE awarded a contract, by way of the University of Utah Research Institute and the Oregon Institute of Technology Geo-Heat Center, to the Division of Geology and Earth Resources (DGER) to update the geothermal database for Washington. DGER with the Washington State Energy Office (WSEO) now assess and encourage geothermal energy uses, especially in the Columbia River basin where shallow geothermal sources are abundant. DGER and WSEO recommend developing existing thermal wells, do further exploration, and institute a long term effort to inform the public of the advantages economic value of utilizing geothermal resources over fossil fuels.

  6. Geothermal Progress Monitor. Report No. 15

    SciTech Connect

    Not Available

    1993-12-01

    Two themes dominate this issue of the Geothermal Progress Monitor, the 15th since its inception in 1980. The first of these is the significance of the government/industry partnership role in geothermal development. This joint effort is reflected in the continued, measured growth in the use of geothermal energy, for both power generation and direct use applications, in this country and abroad, as well as in the development of new, innovative technologies to ensure a bright future for the resource. The second theme is the growing popularity of geothermal heat pumps (GHPs) among utilities, their customers, and federal agencies, all with disparate interests in the technology.

  7. Washington: a guide to geothermal energy development

    SciTech Connect

    Bloomquist, R.G.; Basescu, N.; Higbee, C.; Justus, D.; Simpson, S.

    1980-06-01

    Washington's geothermal potential is discussed. The following topics are covered: exploration, drilling, utilization, legal and institutional setting, and economic factors of direct use projects. (MHR)

  8. A structural model guide for geothermal exploration in Ancestral Mount Bao, Leyte, Philippines

    NASA Astrophysics Data System (ADS)

    Lagmay, M. A.

    2001-12-01

    The Tongonan Geothermal Field, located on the eroded flank of Ancestral Mount Bao (AMB) volcano, is the largest producing geothermal field in the Philippines. It produces about 640 MW of energy supplying power to the grid of Luzon, Visayas, and Mindano, the three major islands of the Philippines. The Tongonan geothermal field is host to several major power plants that tap geothermal power from the northern flank of the AMB volcano. I present a structural model guide for delineating exploration targets in other flanks of the ~1,200 km2 area of the AMB volcano. The model limits the exploration area, where more detailed investigations involving geophysical, and geochemical methods can be applied. This structural model guide is based on analogue sand cone experiments, their comparison with the natural prototype (i.e. AMB volcano), and the observation of the geographic positions of producing geothermal power plants within the Tongonan Geothermal Field. Based on this structural model, I suggest an ideal exploration target on the south-southeastern flank of the AMB, directly overlying the left-lateral Philippine fault.

  9. Semiannual progress report for the Idaho Geothermal Program, October 1, 1979-March 31, 1980

    SciTech Connect

    Ihrig, R.R.

    1980-07-01

    Progress is reported for the Idaho Geothermal program between October 1, 1979 and March 31, 1980. Progress on the 5-MW Pilot Power Plant at the Raft River Geothermal Test Site is summarized including construction, steady-state and transient analyses by computer modeling, the geothermal water treatment program, and additional experimental and theoretical work on direct contact heat exchangers. Asbestos-cement pipe failures in the geothermal fluid supply and injection system are also summarized. The successful automatic control-mode testing of the Prototype Power Plant is reported. A continuing direct applications experiment in aquaculture is outlined, and a proposal to study various ramifications of irrigating agricultural and range lands with spent geothermal fluid is described briefly. Also outlined is the second experimental hydraulic fracture treatment of a geothermal well at Raft River as part of the National Well Stimulation Program. The improvements to the Raft River site facilities are described, and progress in providing technical information and assistance in the Outreach, or User Assistance program presented. Also presented is a new DOE program, the User Coupled Confirmation Drilling Program, which is intended to reduce the financial risk of hydrothermal reservoir exploration by the private sector. Progress reports are also included on DOE's Program Opportunity Notice (PON) Program demonstration projects and Program Research and Development Announcement (PRDA) Program study projects.

  10. Hawaii electric system reliability.

    SciTech Connect

    Silva Monroy, Cesar Augusto; Loose, Verne William

    2012-09-01

    This report addresses Hawaii electric system reliability issues; greater emphasis is placed on short-term reliability but resource adequacy is reviewed in reference to electric consumers' views of reliability %E2%80%9Cworth%E2%80%9D and the reserve capacity required to deliver that value. The report begins with a description of the Hawaii electric system to the extent permitted by publicly available data. Electrical engineering literature in the area of electric reliability is researched and briefly reviewed. North American Electric Reliability Corporation standards and measures for generation and transmission are reviewed and identified as to their appropriateness for various portions of the electric grid and for application in Hawaii. Analysis of frequency data supplied by the State of Hawaii Public Utilities Commission is presented together with comparison and contrast of performance of each of the systems for two years, 2010 and 2011. Literature tracing the development of reliability economics is reviewed and referenced. A method is explained for integrating system cost with outage cost to determine the optimal resource adequacy given customers' views of the value contributed by reliable electric supply. The report concludes with findings and recommendations for reliability in the State of Hawaii.

  11. Photovoltaic performance and reliability workshop

    SciTech Connect

    Kroposki, B

    1996-10-01

    This proceedings is the compilation of papers presented at the ninth PV Performance and Reliability Workshop held at the Sheraton Denver West Hotel on September 4--6, 1996. This years workshop included presentations from 25 speakers and had over 100 attendees. All of the presentations that were given are included in this proceedings. Topics of the papers included: defining service lifetime and developing models for PV module lifetime; examining and determining failure and degradation mechanisms in PV modules; combining IEEE/IEC/UL testing procedures; AC module performance and reliability testing; inverter reliability/qualification testing; standardization of utility interconnect requirements for PV systems; need activities to separate variables by testing individual components of PV systems (e.g. cells, modules, batteries, inverters,charge controllers) for individual reliability and then test them in actual system configurations; more results reported from field experience on modules, inverters, batteries, and charge controllers from field deployed PV systems; and system certification and standardized testing for stand-alone and grid-tied systems.

  12. Power from the hot-dry-rock geothermal resource

    SciTech Connect

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

    1981-01-01

    The history of the development of the first HDR reservoir at the Fenton Hill site is presented. Particulars on the surface piping and data collection system are described, as well as a brief historical account of the individual experiments. Field research results at Fenton Hill are described. From the research, it has been learned that the geothermal reservoir growth is due in large part to pressurization and thermophysical effects. The impedance to flow along the fractures within the reservoir decreases as thermal contraction and pressurization of the reservoir continue to open natural joints. Minimal environmental effects have been noted as a result of closed-system circulation; and the chemical quality of the geothermal fluid has been good, in contrast to the corrosive geothermal fluids in many hydrothermal systems. Some of the general as well as site-specific problems at the Fenton Hill site are discussed. In-spite of these problems, an HDR system is operational, and is being used to answer questions raised by the theoretical research. The types and options of power generation available are addressed. A binary-fluid cycle that can use nonaqueous working fluids is an alternative to single- or multiple-flash systems. These nonaqueous fluids may fall within a large range of hydrocarbon, fluorocarbon, and organic fluids. R-114 was tested in binary cycle at Fenton Hill and was chosen largely for its heat-transfer characteristics and previous industrial experience.

  13. Regional geothermal exploration in Egypt

    NASA Technical Reports Server (NTRS)

    Morgan, P.; Boulos, F. K.; Swanberg, C. A.

    1983-01-01

    A study is presented of the evaluation of the potential geothermal resources of Egypt using a thermal gradient/heat flow technique and a groundwater temperature/chemistry technique. Existing oil well bottom-hole temperature data, as well as subsurface temperature measurements in existing boreholes, were employed for the thermal gradient/heat flow investigation before special thermal gradient holes were drilled. The geographic range of the direct subsurface thermal measurements was extended by employing groundwater temperature and chemistry data. Results show the presence of a regional thermal high along the eastern margin of Egypt with a local thermal anomaly in this zone. It is suggested that the sandstones of the Nubian Formation may be a suitable reservoir for geothermal fluids. These findings indicate that temperatures of 150 C or higher may be found in this reservoir in the Gulf of Suez and Red Sea coastal zones where it lies at a depth of 4 km and deeper.

  14. Boise geothermal district heating system

    SciTech Connect

    Hanson, P.J.

    1985-10-01

    This document describes the Boise geothermal district heating project from preliminary feasibility studies completed in 1979 to a fully operational system by 1983. The report includes information about the two local governments that participated in the project - the City of Boise, Idaho and the Boise Warm Springs Water District. It also discusses the federal funding sources; the financial studies; the feasibility studies conducted; the general system planning and design; design of detailed system components; the legal issues involved in production; geological analysis of the resource area; distribution and disposal; the program to market system services; and the methods of retrofitting buildings to use geothermal hot water for space heating. Technically this report describes the Boise City district heating system based on 170/sup 0/F water, a 4000 gpm production system, a 41,000 foot pipeline system, and system economies. Comparable data are also provided for the Boise Warm Springs Water District. 62 figs., 31 tabs.

  15. The total flow concept for geothermal energy conversion

    NASA Technical Reports Server (NTRS)

    Austin, A. L.

    1974-01-01

    A geothermal development project has been initiated at the Lawrence Livermore Laboratory (LLL) to emphasize development of methods for recovery and conversion of the energy in geothermal deposits of hot brines. Temperatures of these waters vary from 150 C to more than 300 C with dissolved solids content ranging from less than 0.1% to over 25% by weight. Of particular interest are the deposits of high-temperature/high-salinity brines, as well as less saline brines, known to occur in the Salton Trough of California. Development of this resource will depend on resolution of the technical problems of brine handling, scale and precipitation control, and corrosion/erosion resistant systems for efficient conversion of thermal to electrical energy. Research experience to date has shown these problems to be severe. Hence, the LLL program emphasizes development of an entirely different approach called the Total Flow concept.

  16. Geothermal systems of northern Nevada

    USGS Publications Warehouse

    Hose, Richard Kenneth; Taylor, Bruce Edward

    1974-01-01

    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?C, although most are below 190?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?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. We suggest 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.

  17. Process for purifying geothermal steam

    SciTech Connect

    Li, C.T.

    1980-04-01

    Steam containing hydrogen sulfide is purified and sulfur recovered by passing the steam through a reactor packed with activated carbon in the presence of a stoichiometric amount of oxygen which oxidizes the hydrogen sulfide to elemental sulfur which is adsorbed on the bed. The carbon can be recycled after the sulfur has been recovered by vacuum distillation, inert gas entrainment of solvent extraction. The process is suitable for the purification of steam from geothermal sources which may also contain other noncondensable gases.

  18. Process for purifying geothermal steam

    DOEpatents

    Li, Charles T.

    1980-01-01

    Steam containing hydrogen sulfide is purified and sulfur recovered by passing the steam through a reactor packed with activated carbon in the presence of a stoichiometric amount of oxygen which oxidizes the hydrogen sulfide to elemental sulfur which is adsorbed on the bed. The carbon can be recycled after the sulfur has been recovered by vacuum distillation, inert gas entrainment or solvent extraction. The process is suitable for the purification of steam from geothermal sources which may also contain other noncondensable gases.

  19. Process for purifying geothermal steam

    DOEpatents

    Li, C.T.

    Steam containing hydrogen sulfide is purified and sulfur recovered by passing the steam through a reactor packed with activated carbon in the presence of a stoichiometric amount of oxygen which oxidizes the hydrogen sulfide to elemental sulfur which is adsorbed on the bed. The carbon can be recycled after the sulfur has been recovered by vacuum distillation, inert gas entrainment or solvent extraction. The process is suitable for the purification of steam from geothermal sources which may also contain other noncondensable gases.

  20. Annotated geothermal bibliography of Utah

    SciTech Connect

    Budding, K.E.; Bugden, M.H.

    1986-01-01

    The bibliography includes all the Utah geothermal references through 1984. Some 1985 citations are listed. Geological, geophysical, and tectonic maps and reports are included if they cover a high-temperature thermal area. The references are indexed geographically either under (1) United States (national studies), (2) regional - western United States or physiographic province, (3) Utah - statewide and regional, or (4) county. Reports concerning a particular hot spring or thermal area are listed under both the thermal area and the county names.

  1. Feasibility study of sedimentary enhanced geothermal systems using reservoir simulation

    NASA Astrophysics Data System (ADS)

    Cho, Jae Kyoung

    The objective of this research is to evaluate the preliminary feasibility of commercial geothermal projects, from a sedimentary reservoir with low permeability that requires productivity enhancement, using numerical reservoir simulation. The performance of a sedimentary geothermal reservoir is investigated in terms of reservoir hydraulics and thermal evolution. To build a reliable benchmark for simulation study, validation of the numerical reservoir model with respect to an analytical model is presented, and the process to achieve an acceptable match between the numerical and analytical solutions is described. The analytical model used in this study is based on the work of Gringarten (1978), which consists of a conceptual geothermal reservoir, considering an injection and production well doublet in a homogeneous porous media. A commercial thermal reservoir simulator (STARS from Computer Modeling Group, CMG) is used in this work for numerical modeling. In order to reproduce the analytical model results, the numerical simulation model is modified to include the same assumptions of the analytical model. Simulation model parameters that make the numerical results deviate from the analytical solution, such as the grid block size, time step and no-flow boundary are identified and investigated. An analytical tracer test model proposed by Shook (2000) is numerically modeled. This model allows us to predict the time when the temperature of the produced water decreases by capturing a tracer component at production well. Reservoir simulation models with different porosity and permeability distribution are tested to see the effects of reservoir inhomogeneity and anisotropy. In particular, premature thermal breakthrough due to the presence of high permeability streak in a reservoir model is simulated. In an effort to apply the knowledge we obtained from the analytical solutions, the effects of reservoir rock and water properties, as a function of pressure and temperature, are

  2. Using a new Geothermal Well Field as a Field Laboratory to Facilitate Comprehensive Knowledge

    NASA Astrophysics Data System (ADS)

    Neumann, K.; Dowling, C. B.

    2011-12-01

    In Fall 2010, the faculty of the Department of Geological Sciences at Ball State University (BSU) took advantage of several recently drilled monitoring wells within BSU's newly constructed ground-source geothermal well field, currently the largest in the U.S., to create an undergraduate field laboratory for hydrogeological experiments. Using the Investigative Case-Based Learning approach, upper-level undergraduate students developed research projects that would assist BSU's Facilities in evaluating and maintaining the geothermal fields. The students designed original hypotheses and explored how to test them with the available equipment within one semester. They focused on observing and measuring the potential impact of the geothermal well field on groundwater temperature and flow direction using two shallow monitoring wells in gravel (~30 ft) and eight deeper monitoring wells in limestone (~70 ft). The results will be used for comparisons when the geothermal plant goes online in Fall 2011. Undergraduate and graduate students will perform experiments throughout this initial period and continue even after the geothermal field is activated. Through the use of different assessment tools, including peer evaluation, instructors' assessment and an assessment of understanding, we determined that twenty-five percent of the class gained full comprehensive understanding. These students were able to design new experiments by assessing their semester data, integrating their knowledge from previous classes, and synthesizing new hypotheses. The majority of the class was able to further expand their understanding of the scientific process, but not to the extent as the top students.

  3. Geothermal Prospector: Supporting Geothermal Analysis Through Spatial Data Visualization and Querying Tools

    SciTech Connect

    Getman, Daniel; Anderson, Arlene; Augustine, Chad

    2015-09-02

    Determining opportunities for geothermal energy can involve a significant investment in data collection and analysis. Analysts within a variety of industry and research domains collect and use these data; however, determining the existence and availability of data needed for a specific analysis activity can be challenging and represents one of the initial barriers to geothermal development [2]. This paper describes the motivating factors involved in designing and building the Geothermal Prospector application, how it can be used to reduce risks and costs related to geothermal exploration, and where it fits within the larger collection of tools that is the National Geothermal Data System (NGDS) [5].

  4. Archean geotherms and supracrustal assemblages

    NASA Astrophysics Data System (ADS)

    Condie, Kent C.

    1984-06-01

    Metamorphic mineral assemblages suggest the existence of variable geotherms and lithospheric thicknesses beneath late Archean continental crust. Archean granite-greenstone terranes reflect steep geotherms (50-70°C/km) while high-grade terranes reflect moderate geotherms similar to present continental crust with high heat flow (25-40°C/km). Corresponding lithosphere thicknesses for each terrane during the late Archean are 35-50 km and 50-75 km, respectively. Early Archean (⩾ 3.0 b.y.) greenstones differ from late Archean (˜ 2.7 b.y.) greenstones by the rarity or absence of andesite and graywacke and the relative abundance of pelite, quartzite, and komatiite. Mature clastic sediments in early greenstones reflect shallow-water, stable-basin deposition. Such rocks, together with granite-bearing conglomerate and felsic volcanics imply the existence of still older granitic source terranes. The absence or rarity of andesite in early greenstones reflects the absence of tectonic conditions in which basaltic and tonalitic magmas are modified to produce andesite. A model is presented in which early Archean greenstones form at the interface between tonalite islands and oceanic lithosphere, over convective downcurrents; high-grade supracrustals form on stable continental edges or interiors; and late Archean greenstones form in intracontinental rifts over mantle plumes.

  5. Klamath Falls geothermal field, Oregon

    SciTech Connect

    Lienau, P.J.; Culver, G.; Lund, J.W.

    1989-09-01

    Klamath Falls, Oregon, is located in a Known Geothermal Resource Area which has been used by residents, principally to obtain geothermal fluids for space heating, at least since the turn of the century. Over 500 shallow-depth wells ranging from 90 to 2,000 ft (27 to 610 m) in depth are used to heat (35 MWt) over 600 structures. This utilization includes the heating of homes, apartments, schools, commercial buildings, hospital, county jail, YMCA, and swimming pools by individual wells and three district heating systems. Geothermal well temperatures range from 100 to 230{degree}F (38 to 110{degree}C) and the most common practice is to use downhole heat exchangers with city water as the circulating fluid. Larger facilities and district heating systems use lineshaft vertical turbine pumps and plate heat exchangers. Well water chemistry indicates approximately 800 ppM dissolved solids, with sodium sulfate having the highest concentration. Some scaling and corrosion does occur on the downhole heat exchangers (black iron pipe) and on heating systems where the geo-fluid is used directly. 73 refs., 49 figs., 6 tabs.

  6. Evaluating Geothermal Potential in Germany by Numerical Reservoir Modeling of Engineered Geothermal Systems

    NASA Astrophysics Data System (ADS)

    Jain, Charitra; Vogt, Christian; Clauser, Christoph

    2014-05-01

    We model hypothetical Engineered Geothermal System (EGS) reservoirs by solving coupled partial differential equations governing fluid flow and heat transport. Building on EGS's strengths of inherent modularity and storage capability, it is possible to implement multiple wells in the reservoir to extend the rock volume accessible for circulating water in order to increase the heat yield. By varying parameters like flow rates and well-separations in the subsurface, this study looks at their long-term impacts on the reservoir development. This approach allows us to experiment with different placements of the engineered fractures and propose several EGS layouts for achieving optimized heat extraction. Considering the available crystalline area and accounting for the competing land uses, this study evaluates the overall EGS potential and compares it with those of other used renewables in Germany. There is enough area to support 13450 EGS plants, each with six reversed-triplets (18 wells) and an average electric power of 35.3MWe. When operated at full capacity, these systems can collectively supply 4155TWh of electric energy in one year which would be roughly six times the electric energy produced in Germany in the year 2011. Engineered Geothermal Systems make a compelling case for contributing towards national power production in a future powered by a sustainable, decentralized energy system.

  7. Geothermal direct applications hardware systems development and testing. 1979 summary report

    SciTech Connect

    Keller, J.G.

    1980-03-01

    Activities performed during calendar year 1979 for the hardware system development and testing task are presented. The fluidized bed technology was applied to the drying of potato by-products and to the exchange of heat to air in the space heating experiment. Geothermal water was flashed to steam and also used as the prime energy source in the steam distillation of peppermint oil. Geothermal water temperatures as low as 112.8/sup 0/C were utilized to distill alcohol from sugar beet juice, and lower temperature water provided air conditioning through an absorption air conditioning system. These experiments are discussed.

  8. Update and assessment of geothermal economic models, geothermal fluid flow and heat distribution models, and geothermal data bases

    SciTech Connect

    Kenkeremath, D.

    1985-05-01

    Numerical simulation models and data bases that were developed for DOE as part of a number of geothermal programs have been assessed with respect to their overall stage of development and usefulness. This report combines three separate studies that focus attention upon: (1) economic models related to geothermal energy; (2) physical geothermal system models pertaining to thermal energy and the fluid medium; and (3) geothermal energy data bases. Computerized numerical models pertaining to the economics of extracting and utilizing geothermal energy have been summarized and catalogued with respect to their availability, utility and function. The 19 models that are discussed in detail were developed for use by geothermal operators, public utilities, and lending institutions who require a means to estimate the value of a given resource, total project costs, and the sensitivity of these values to specific variables. A number of the models are capable of economically assessing engineering aspects of geothermal projects. Computerized simulations of heat distribution and fluid flow have been assessed and are presented for ten models. Five of the models are identified as wellbore simulators and five are described as reservoir simulators. Each model is described in terms of its operational characteristics, input, output, and other pertinent attributes. Geothermal energy data bases are reviewed with respect to their current usefulness and availability. Summaries of eight data bases are provided in catalogue format, and an overall comparison of the elements of each data base is included.

  9. Geothermal areas as analogues to chemical processes in the near-field and altered zone of the potential Yucca Mountain, Nevada repository

    SciTech Connect

    Bruton, C.J.; Glassley, W.E.; Meike, A.

    1995-02-01

    The need to bound system performance of the potential Yucca Mountain repository for thousands of years after emplacement of high-level nuclear waste requires the use of computer codes. The use of such codes to produce reliable bounds over such long time periods must be tested using long-lived natural and historical systems as analogues. The geothermal systems of the Taupo Volcanic Zone (TVZ) in New Zealand were selected as the site most amenable to study. The rocks of the TVZ are silicic volcanics that are similar in composition to Yucca Mountain. The area has been subjected to temperatures of 25 to 300 C which have produced a variety of secondary minerals similar to those anticipated at Yucca Mountain. The availability of rocks, fluids and fabricated materials for sampling is excellent because of widespread exploitation of the systems for geothermal power. Current work has focused on testing the ability of the EQ3/6 code and thermodynamic data base to describe mineral-fluid relations at elevated temperatures. Welfare starting long-term dissolution/corrosion tests of rocks, minerals and manufactured materials in natural thermal features in order to compare laboratory rates with field-derived rates. Available field data on rates of silica precipitation from heated fluids have been analyzed and compared to laboratory rates. New sets of precipitation experiments are being planned. The microbially influenced degradation of concrete in the Broadlands-Ohaaki geothermal field is being characterized. The authors will continue to work on these projects in FY 1996 and expand to include the study of naturally occurring uranium and thorium series radionuclides, as a prelude to studying radionuclide migration in heated silicic volcanic rocks. 32 refs.

  10. National Geothermal Data System: State Geological Survey Contributions to Date

    NASA Astrophysics Data System (ADS)

    Patten, K.; Allison, M. L.; Richard, S. M.; Clark, R.; Love, D.; Coleman, C.; Caudill, C.; Matti, J.; Musil, L.; Day, J.; Chen, G.

    2012-12-01

    In collaboration with the Association of American State Geologists the Arizona Geological Survey is leading the effort to bring legacy geothermal data to the U.S. Department of Energy's National Geothermal Data System (NGDS). NGDS is a national, sustainable, distributed, interoperable network of data and service (application) providers entering its final stages of development. Once completed the geothermal industry, the public, and policy makers will have access to consistent and reliable data, which in turn, reduces the amount of staff time devoted to finding, retrieving, integrating, and verifying information. With easier access to information, the high cost and risk of geothermal power projects (especially exploration drilling) is reduced. This presentation focuses on the scientific and data integration methodology as well as State Geological Survey contributions to date. The NGDS is built using the U.S. Geoscience Information Network (USGIN) data integration framework to promote interoperability across the Earth sciences community and with other emerging data integration and networking efforts. Core to the USGIN concept is that of data provenance; by allowing data providers to maintain and house their data. After concluding the second year of the project, we have nearly 800 datasets representing over 2 million data points from the state geological surveys. A new AASG specific search catalog based on popular internet search formats enables end users to more easily find and identify geothermal resources in a specific region. Sixteen states, including a consortium of Great Basin states, have initiated new field data collection for submission to the NGDS. The new field data includes data from at least 21 newly drilled thermal gradient holes in previously unexplored areas. Most of the datasets provided to the NGDS are being portrayed as Open Geospatial Consortium (OGC) Web Map Services (WMS) and Web Feature Services (WFS), meaning that the data is compatible with a

  11. Photovoltaic system reliability

    SciTech Connect

    Maish, A.B.; Atcitty, C.; Greenberg, D.

    1997-10-01

    This paper discusses the reliability of several photovoltaic projects including SMUD`s PV Pioneer project, various projects monitored by Ascension Technology, and the Colorado Parks project. System times-to-failure range from 1 to 16 years, and maintenance costs range from 1 to 16 cents per kilowatt-hour. Factors contributing to the reliability of these systems are discussed, and practices are recommended that can be applied to future projects. This paper also discusses the methodology used to collect and analyze PV system reliability data.

  12. Power Quality and Reliability Project

    NASA Technical Reports Server (NTRS)

    Attia, John O.

    2001-01-01

    One area where universities and industry can link is in the area of power systems reliability and quality - key concepts in the commercial, industrial and public sector engineering environments. Prairie View A&M University (PVAMU) has established a collaborative relationship with the University of'Texas at Arlington (UTA), NASA/Johnson Space Center (JSC), and EP&C Engineering and Technology Group (EP&C) a small disadvantage business that specializes in power quality and engineering services. The primary goal of this collaboration is to facilitate the development and implementation of a Strategic Integrated power/Systems Reliability and Curriculum Enhancement Program. The objectives of first phase of this work are: (a) to develop a course in power quality and reliability, (b) to use the campus of Prairie View A&M University as a laboratory for the study of systems reliability and quality issues, (c) to provide students with NASA/EPC shadowing and Internship experience. In this work, a course, titled "Reliability Analysis of Electrical Facilities" was developed and taught for two semesters. About thirty seven has benefited directly from this course. A laboratory accompanying the course was also developed. Four facilities at Prairie View A&M University were surveyed. Some tests that were performed are (i) earth-ground testing, (ii) voltage, amperage and harmonics of various panels in the buildings, (iii) checking the wire sizes to see if they were the right size for the load that they were carrying, (iv) vibration tests to test the status of the engines or chillers and water pumps, (v) infrared testing to the test arcing or misfiring of electrical or mechanical systems.

  13. Long-term predictions of minewater geothermal systems heat resources

    NASA Astrophysics Data System (ADS)

    Harcout-Menou, Virginie; de ridder, fjo; laenen, ben; ferket, helga

    2014-05-01

    Abandoned underground mines usually flood due to the natural rise of the water table. In most cases the process is relatively slow giving the mine water time to equilibrate thermally with the the surrounding rock massif. Typical mine water temperature is too low to be used for direct heating, but is well suited to be combined with heat pumps. For example, heat extracted from the mine can be used during winter for space heating, while the process could be reversed during summer to provide space cooling. Altough not yet widely spread, the use of low temperature geothermal energy from abandoned mines has already been implemented in the Netherlands, Spain, USA, Germany and the UK. Reliable reservoir modelling is crucial to predict how geothermal minewater systems will react to predefined exploitation schemes and to define the energy potential and development strategy of a large-scale geothermal - cold/heat storage mine water systems. However, most numerical reservoir modelling software are developed for typical environments, such as porous media (a.o. many codes developed for petroleum reservoirs or groundwater formations) and cannot be applied to mine systems. Indeed, mines are atypical environments that encompass different types of flow, namely porous media flow, fracture flow and open pipe flow usually described with different modelling codes. Ideally, 3D models accounting for the subsurface geometry, geology, hydrogeology, thermal aspects and flooding history of the mine as well as long-term effects of heat extraction should be used. A new modelling approach is proposed here to predict the long-term behaviour of Minewater geothermal systems in a reactive and reliable manner. The simulation method integrates concepts for heat and mass transport through various media (e.g., back-filled areas, fractured rock, fault zones). As a base, the standard software EPANET2 (Rossman 1999; 2000) was used. Additional equations for describing heat flow through the mine (both

  14. Geothermal Progress Monitor report No. 11

    SciTech Connect

    Not Available

    1989-12-01

    This issue of the Geothermal Progress Monitor (GPM) is the 11th since the inception of the publication in 1980. It continues to synthesize information on all aspects of geothermal development in this country and abroad to permit identification and quantification of trends in the use of this energy technology. In addition, the GPM is a mechanism for transferring current information on geothermal technology development to the private sector, and, over time, provides a historical record for those interested in the development pathway of the resource. In sum, the Department of Energy makes the GPM available to the many diverse interests that make up the geothermal community for the multiple uses it may serve. This issue of the GPM points up very clearly how closely knit many of those diverse interests have become. It might well be called an international issue'' since many of its pages are devoted to news of geothermal development abroad, to the efforts of the US industry to participate in overseas development, to the support given those efforts by federal and state agencies, and to the formation of the International Geothermal Association (IGA). All of these events indicate that the geothermal community has become truly international in character, an occurrence that can only enhance the future of geothermal energy as a major source of energy supply worldwide. 15 figs.

  15. Geothermal progress monitor: Report Number 19

    SciTech Connect

    1997-12-01

    Short articles are presented related to activities in the federal government and the geothermal industry, international developments, state and local government activities, technology development, and technology transfer. Power plant tables and a directory of organizations involved in geothermal resource development are included.

  16. Geothermal Cogeneration: Iceland's Nesjavellir Power Plant

    ERIC Educational Resources Information Center

    Rosen, Edward M.

    2008-01-01

    Energy use in Iceland (population 283,000) is higher per capita than in any other country in the world. Some 53.2% of the energy is geothermal, which supplies electricity as well as heated water to swimming pools, fish farms, snow melting, greenhouses, and space heating. The Nesjavellir Power Plant is a major geothermal facility, supplying both…

  17. State Geothermal Data data delivery tools

    Energy Science and Technology Software Center (ESTSC)

    2009-08-01

    This web site provides a single online system for AASG State Geothermal Data participants to integrate their data into the NGDS, discovering how to digitize at-risk, legacy, geothermal-relevant data and combine it with existing digital data to create a publicly accessible system.

  18. Puna Geothermal Venture Hydrologic Monitoring Program

    SciTech Connect

    1990-04-01

    This document provides the basis for the Hydrologic Monitoring Program (HMP) for the Puna Geothermal Venture. The HMP is complementary to two additional environmental compliance monitoring programs also being submitted by Puma Geothermal Venture (PGV) for their proposed activities at the site. The other two programs are the Meteorology and Air Quality Monitoring Program (MAQMP) and the Noise Monitoring Program (NMP), being submitted concurrently.

  19. Civil litigation and the geothermal industry

    SciTech Connect

    Moore, George M.

    1991-01-01

    This paper offers some reflections on the interactions between the legal profession and the realm of the geothermal scientist and engineer. The author, now a litigation attorney, became an attorney after about fifteen years as an engineer and physicist. Over the past several years the author was involved in litigation related to geothermal contracts.

  20. Geothermal Power/Oil & Gas Coproduction Opportunity

    SciTech Connect

    DOE

    2012-02-01

    Coproduced geothermal resources can deliver near-term energy savings, diminish greenhouse gas emissions, extend the economic life of oil and gas fields, and profitably utilize oil and gas field infrastructure. This two-pager provides an overview of geothermal coproduced resources.