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Sample records for geothermal energy field

  1. Symposium in the field of geothermal energy

    SciTech Connect

    Ramirez, Miguel; Mock, John E.

    1989-04-01

    Mexico and the US are nations with abundant sources of geothermal energy, and both countries have progressed rapidly in developing their more accessible resources. For example, Mexico has developed over 600 MWe at Cerro Prieto, while US developers have brought in over 2000 MWe at the Geysers. These successes, however, are only a prologue to an exciting future. All forms of energy face technical and economic barriers that must be overcome if the resources are to play a significant role in satisfying national energy needs. Geothermal energy--except for the very highest grade resources--face a number of barriers, which must be surmounted through research and development. Sharing a common interest in solving the problems that impede the rapid utilization of geothermal energy, Mexico and the US agreed to exchange information and participate in joint research. An excellent example of this close and continuing collaboration is the geothermal research program conducted under the auspices of the 3-year agreement signed on April 7, 1986 by the US DOE and the Mexican Comision Federal de Electricidad (CFE). The major objectives of this bilateral agreement are: (1) to achieve a thorough understanding of the nature of geothermal reservoirs in sedimentary and fractured igneous rocks; (2) to investigate how the geothermal resources of both nations can best be explored and utilized; and (3) to exchange information on geothermal topics of mutual interest.

  2. 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)…

  3. 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…

  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

    In July 2011, the first geothermal field camp was hold on Java/Indonesia near the city Bandung south of the volcanic field Tangkuban Perahu. The course was organized by the Institut Teknologie Bandung (ITB) and International Centre for Geothermal Research (ICGR) of the German Centre of Geosciences (GFZ). The purpose of the Geothermal Field Camp is to combine both field based work and laboratory analysis to ultimately better understand the data collected in field and to integrate data gained by various disciplines. The training belongs to a capacity building program for geothermal energy systems in Indonesia and initially aims to train the trainers. In a later stage, the educational personal trained by the Geothermal Field Camp shall be able to hold their individual Geothermal Field Camp. This is of special interest for Indonesia where the multitude of islands hindered a broad uniform education in geothermal energy systems. However, Indonesia hold the largest geothermal potential worldwide and educated personal is necessary to successfully develop this huge potential scattered over region in future. The interdisciplinary and integrative approach combined with field based and laboratory methodologies is the guiding principle of the Geothermal Field Camp. Tangkuban Perahu was selected because this field allows the integration of field based structural geological analysis, observation and sampling of geothermal manifestations as hot springs and sinters and ultimately of structural geology and surface geochemistry. This innovative training introduces in methods used in exploration geology to study both, fault and fracture systems and fluid chemistry to better understand the selective fluid flow along certain fractures and faults. Field geology covered the systematic measurement of faults and fractures, fault plane and fracture population analysis. In addition, field hydro-geochemistry focused on sampling techniques and field measurements onsite. Subsequent data analysis

  5. 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.

  6. 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)

  7. 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)

  8. 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.…

  9. 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.

  10. Geothermal Energy - An Emerging Resource

    SciTech Connect

    Berg, John R.

    1987-01-20

    Address on the Department of Energy's overall energy policy, the role of alternative energy sources within the policy framework, and expectations for geothermal energy. Commendation of the industry's decision to pursue the longer-term field effort while demand for geothermal energy is low, and thus prepare for a substantial geothermal contribution to the nation's energy security.

  11. 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.

  12. 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.

  13. Geothermal Energy Summary

    SciTech Connect

    J. L. Renner

    2007-08-01

    -traditional geothermal development is increasing. A comprehensive new MIT-led study of the potential for geothermal energy within the United States predicts that mining the huge amounts of stored thermal energy in the Earth’s crust not associated with hydrothermal systems, could supply a substantial portion of U.S. electricity with minimal environmental impact (Tester, et al., 2006, available at http://geothermal.inl.gov). There is also renewed interest in geothermal production from other non-traditional sources such as the overpressured zones in the Gulf Coast and warm water co-produced with oil and gas. Ormat Technologies, Inc., a major geothermal company, recently acquired geothermal leases in the offshore overpressured zone of Texas. Ormat and the Rocky Mountain Oilfield Testing Center recently announced plans to jointly produce geothermal power from co-produced water from the Teapot Dome oilfield (Casper Star-Tribune, March 2, 2007). RMOTC estimates that 300 KWe capacity is available from the 40,000 BWPD of 88°C water associated with oil production from the Tensleep Sandstone (Milliken, 2007). The U. S. Department of Energy is seeking industry partners to develop electrical generation at other operating oil and gas fields (for more information see: https://e-center.doe.gov/iips/faopor.nsf/UNID/50D3734745055A73852572CA006665B1?OpenDocument). Several web sites offer periodically updated information related to the geothermal industry and th

  14. 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)

  15. 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.

  16. Energy 101: Geothermal Energy

    ScienceCinema

    None

    2016-07-12

    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.

  17. 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.

  18. 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.

  19. 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.

  20. 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)

  1. Geothermal Energy & Economic Development

    SciTech Connect

    2004-07-01

    Whether they are used to generate electricity or for direct-use applications, geothermal energy projects contribute to the economy of areas where they are located. Geothermal power plant operations are often a major source of tax revenue to local governments.

  2. 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.

  3. 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)

  4. CNCC Craig Campus Geothermal Project: 82-well closed loop GHP well field to provide geothermal energy as a common utilitiy for a new community college campus

    SciTech Connect

    Chevron Energy Solutions; Matt Rush; Scott Shulda

    2011-01-03

    Colorado Northwestern Community College (CNCC) is working collaboratively with recipient vendor Chevron Energy Solutions, an energy services company (ESCO), to develop an innovative GHP project at the new CNCC Campus constructed in 2010/2011 in Craig, Colorado. The purpose of the CNCC Craig Campus Geothermal Program scope was to utilize an energy performance contracting approach to develop a geothermal system with a shared closed-loop field providing geothermal energy to each building's GHP mechanical system. Additional benefits to the project include promoting good jobs and clean energy while reducing operating costs for the college. The project has demonstrated that GHP technology is viable for new construction using the energy performance contracting model. The project also enabled the project team to evaluate several options to give the College a best value proposition for not only the initial design and construction costs but build high performance facilities that will save the College for many years to come. The design involved comparing the economic feasibility of GHP by comparing its cost to that of traditional HVAC systems via energy model, financial life cycle cost analysis of energy savings and capital cost, and finally by evaluating the compatibility of the mechanical design for GHP compared to traditional HVAC design. The project shows that GHP system design can be incorporated into the design of new commercial buildings if the design teams, architect, contractor, and owner coordinate carefully during the early phases of design. The public also benefits because the new CNCC campus is a center of education for the much of Northwestern Colorado, and students in K-12 programs (Science Spree 2010) through the CNCC two-year degree programs are already integrating geothermal and GHP technology. One of the greatest challenges met during this program was coordination of multiple engineering and development stakeholders. The leadership of Principle Investigator

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. Computers in geothermal energy

    SciTech Connect

    Pettinger, F.E.

    1984-10-01

    This article describes a data base and file management system for the IBM/PC, and gives a general idea of how the Power Base (PB) system might be applied to the running of a typical geothermal business. Requirements for running PB are a monitor, at least 256K, and two double-sided disk drives or a single drive and a hard disk. The relational data base created by PB is organized in filing card type records that are composed of fields. When a file is created, it can be designed according to a company's specific requirements and can allow changes in the layout at any time. Geothermal businesses can use this software package for shipping and client invoice tracking, most billing functions, inventory calculations and mailing data bases. Geothermal project planners might find PB's project tracking aspect useful.

  10. 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)

  11. Status of non-electric use of geothermal energy in the Southern Negros geothermal field in the Philippines

    SciTech Connect

    Chua, S.E.; Abito, G.F.

    1994-07-01

    A 1-MWt multi-crop drying facility using low-enthalpy waste geothermal heat is installed within the vicinity of the Southern Negros Geothermal Project (January, 1994). The plant is envisioned to demonstrate the direct use of geothermal resources for agro-industrial purposes and at the same time, provide major benefits by raising the quality of the agro-industrial products to meet higher standards. The development and design of the heat exchangers that supply the heat and the dryer used in the facility is presented. The process flow and the dryer parameters in the drying of coconut meat and other crops have been determined. The initial design of the dryers target the dehydration of coconut meat and other crops using boxes and trays.

  12. Wood and fruit drying in Los Azufres geothermal field, Mexico

    SciTech Connect

    Casimiro, E.; Pastrana, E.

    1996-12-31

    The main object of Comision Federal de Electricidad (CFE`s) Geothermal Field at Los Azufres, is to generate geothermal electricity; however with the new politics in Mexico CFE has built a pilot project in order to profit from the geothermal residual energy and to attract national or foreign investors and convince them that direct-use of geothermal energy is an attractive feasible and economical possibility. The object of this paper is to present the CFE experiences in wood and fruit drying using geothermal energy.

  13. 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

  14. 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.

  15. 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.

  16. 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…

  17. 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)

  18. Geothermal energy in Nevada: Development and utilization

    NASA Astrophysics Data System (ADS)

    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.

  19. Energy 101: Geothermal Heat Pumps

    ScienceCinema

    None

    2016-07-12

    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.

  20. 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.

  1. 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.

  2. 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)

  3. 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.

  4. Improved energy recovery from geothermal reservoirs

    SciTech Connect

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

    1981-01-01

    The behavior of a liquid-dominated geothermal reservoir in response to production from different horizons is studied using numerical simulation methods. The Olkaria geothermal field in Kenya is used as an example where a two-phase vapor-dominated zone overlies the main liquid-dominated reservoir. The possibility of improving energy recovery from vapor-dominated reservoirs by tapping deeper horizons is considered.

  5. 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)

  6. 1985 international symposium on geothermal energy: international volume

    SciTech Connect

    Stone, C.

    1985-01-01

    This book presents information on geothermal electric power and discusses direct uses of geothermal energy. Country update reports are provided and international cooperation reports include topics such as: selected titles for a basic geothermal library, the role of the United Nations in the field of geothermal resources exploration in developing countries, and geothermal training at the International Institute for Geothermal research. International invited papers in this volume include: Hot Dry Rock--A European Perspective; A Summary of Modeling Studies of the East Okkaria Geothermal Field, Kenya; and The Latest Development of the Los Asufres Geothermal Field in Mexico. General papers are presented from Europe, the Western Pacific, Africa, North America, India, China, and Southeast Asia.

  7. Neutron imaging for geothermal energy systems

    SciTech Connect

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

    2013-01-01

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

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

    SciTech Connect

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

    2003-08-14

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

  9. 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.

  10. Subsurface geology and potential for geopressured-geothermal energy in the Turtle Bayou field-Kent Bayou field area, Terrebonne Parish, Louisiana

    SciTech Connect

    Moore, D.R.

    1982-09-01

    A 216 square mile area approximately 65 miles southwest of New Orleans, Louisiana, has been geologically evaluated to determine its potential for geopressured-geothermal energy production. The structural and stratigraphic analyses were made with emphasis upon the Early and Middle Miocene age sediments which lie close to and within the geopressured section. Three geopressured sands, the Robulus (43) sand, Cibicides opima sand, and Cristellaria (I) sand, are evaluated for their potential of producing geothermal energy. Two of these sands, the Robulus (43) sand and the Cibicides opima sand, meet several of the United States Department of Energy's suggested minimum requirements for a prospective geopressured-geothermal energy reservoir.

  11. Geothermal Program Review XI: proceedings. Geothermal Energy - The Environmental Responsible Energy Technology for the Nineties

    SciTech Connect

    Not Available

    1993-10-01

    These proceedings contain papers pertaining to current research and development of geothermal energy in the USA. The seven sections of the document are: Overview, The Geysers, Exploration and Reservoir Characterization, Drilling, Energy Conversion, Advanced Systems, and Potpourri. The Overview presents current DOE energy policy and industry perspectives. Reservoir studies, injection, and seismic monitoring are reported for the geysers geothermal field. Aspects of geology, geochemistry and models of geothermal exploration are described. The Drilling section contains information on lost circulation, memory logging tools, and slim-hole drilling. Topics considered in energy conversion are efforts at NREL, condensation on turbines and geothermal materials. Advanced Systems include hot dry rock studies and Fenton Hill flow testing. The Potpourri section concludes the proceedings with reports on low-temperature resources, market analysis, brines, waste treatment biotechnology, and Bonneville Power Administration activities. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

  12. 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.

  13. Re-examining Potential for Geothermal Energy in United States

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    New technological initiatives, along with potential policy and economic incentives, could help to bring about a resurgence in geothermal energy development in the United States, said several experts at a 22 May forum in Washington, D.C. The forum was sponsored by the House and Senate Renewable Energy and Energy Efficiency Caucuses, the Sustainable Energy Coalition, and the Environmental and Energy Study Institute. Among these initiatives is an ambitious program of the U.S. Department of Energy to expand existing geothermal energy fields and potentially create new fields through ``enhanced geothermal systems.'' In addition, a program of the Bush administration encourages geothermal development on some public lands, and current legislation would provide tax credits and other incentives for geothermal development.

  14. Geothermal field's interaction with geophysical fields of another nature

    SciTech Connect

    Novik, Oleg B.; Mikhailovskaya, Irina B.; Repin, Dmitry G.; Yershov, Sergey V.

    1996-01-24

    The energy balance of active lithosphere zones is to a large extent determined by nonstationary interaction of mechanical (elastic and hydrodynamic), thermal, electromagnetic, and gravitational geophysical fields. Seismic disturbances of electromagnetic and temperature fields, repeatedly observed before earthquakes are a striking manifestation of this interaction (Sec. 1). Technological processes of exploitation of hydrothermal deposits are determined by the interaction of hydrodynamical and temperature field (Sec. 2). These “fast” interactions (with the characteristic time scale from seconds to years) take place against the background of “slow” thermomechanical interactions (time scale of Myears), the latter determining the formation of regional geothermal fields (Sec. 3).

  15. 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.

  16. Status and trends in geothermal energy

    SciTech Connect

    Roberts, V.W.

    1985-12-01

    Use of geothermal energy for generating electricity on a worldwide basis has increased an average of 16.5 % per year since 1978. Worldwide generating capacity is now around 4600 MW(e). Present US capacity is 1500 MS(e) (installed) with 666 MW(e) under construction and another 963 MW(e) on the drawing boards. Worldwide, 36% of all generating capacity is derived from geothermal steam fields while 54% is derived from hot water fields. In the US 95 % of all generating capacity comes from The Geysers steam field in Northern California with only 5% coming from various hot water fields. However, this ratio is beginning to change as more hot water projects reach maturity. Thirty percent of new capacity now under construction and planned will be derived from hot water geothermal fields. By the year 2000 hot water resources are expected to contribute about 60% of the total US geothermal generating capacity. This paper briefly discusses resource development, power cycle technology, scale and corrosion control, environmental control, system reliability, and power plant cost and financing.

  17. Geothermal Fields on the Volcanic Axis of Mexico

    SciTech Connect

    Mercado, S.; Gonzalez, A.

    1980-12-16

    At present in Mexico, geothermal energy is receiving a great impulse due to the excellent results obtained in the Cerro Prieto geothermal field, in which a geothermoelectric plant is operated. This plant has four units of 37.5 MW each, with a total capacity of 150 MW, and under program 470 MW more by 1984. The Government Institution, Comisi6n Federal de Electricidad, is in charge of the exploration and exploitation of geothermal fields as well as construction and operation of power plants in Mexico. By this time CFE has an extensive program of exploration in the central part of Mexico, in the Eje Neovolcdnico. In this area, several fields with hydrothermal alteration are under exploration, like the Michoac6n geothermal area, where Los Azufres geothermal field is being developed. Seventeen wells have been drilled and twelve of them presented excellent results, including two dry steam wells. In other areas, such as Arar6, Cuitzeo, San Agustln del Maiz,Ixtldn de Los Hervores and Los Negritos, geological, geophysical and geochemical explorations have been accomplished, including shallow well drilling with good results. Another main geothermal area is in the State of Jalisco with an extension of 5,000 m2, where La Primavera geothermal field shows a lot of volcanic domes and has an intensive hydrothermal activity. Deep wells have been drilled, one of them with a bottom temperature of 29OOC. Other fields in this area, like San Narcos, Hervores de La Vega, La Soledad, Villa Corona, etc., have a good geothermal potential. A new geothermal area has been explored recently in the eastern part of the country named Los Humeros, Puebla. In this area studies are being made and there are plans for well drilling exploration by the beginning of 1981. Like this one, there are many other areas in the country in which 300 hydrothermal alteration zones are been classified and 100 of them are considered economically exploitable.

  18. 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.

  19. 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)

  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. 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.

  2. "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

  3. 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)

  4. 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)

  5. 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)

  6. 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)

  7. Irrigation pumping using geothermal energy

    SciTech Connect

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

    1982-08-01

    The potential of using geothermal energy in an isobutane binary system to drive directly a cluster of irrigation pumps was evaluated. This three well geothermal system, based at 150{sup 0}C (302{sup 0}F) resource at 2000 m (6560 ft), would cost an estimated $7,800,000 in capital investment to provide 6000 gpm of irrigation water from 12 water wells. It would serve approximately 4.5 square miles of irrigated agricultural land, with the delivered water costing $106.76 per acre-foot. This compares with an estimated cost of $60.78 per acre-foot for a conventional irrigation system driven by natural gas at the current price (1980 dollars) of $2.72/mm Btu. It is obvious that if natural gas prices continue to rise, or if geothermal resources can be found at depths less than 2000 meters, then the geothermal irrigation pumping system would be attractive economically. The importance of water to the economy and growth of Arizona was summarized. Total water consumption in Arizona is about 7,600,000 acre-feet annually of which about 87% is used for agriculture. Total supply from the Colorado River and water runoff is only 2,600,000 acre-feet per year, resulting in a net potable groundwater depletion of about 4,000,000 acre-feet per year assuming a recharge rate of about 1,000,000 acre-feet per year.

  8. Irrigation pumping using geothermal energy

    NASA Astrophysics Data System (ADS)

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

    1982-08-01

    The potential of using geothermal energy in an isobutane binary system to drive directly a cluster of irrigation pumps was evaluated. This three well geothermal system, based at 1500 C (3020 F) resource at 2000 m (6560 ft), would cost an estimated $7,800,000 in capital investment to provide 6000 gpm of irrigation water from 12 water wells. It would serve approximately 4.5 square miles of irrigated agricultural land, with the delivered water costing $106.76 per acre-foot. This compares with an estimated cost of $60.78 per acre-foot for a conventional irrigation system driven by natural gas at the current price (1980 dollars) of $2.72/mm Btu. It is obvious that if natural gas prices continue to rise, or if geothermal resources can be found at depths less than 2000 meters, then the geothermal irrigation pumping system would be attractive economically. The importance of water to the economy and growth of Arizona was summarized. Total water consumption in Arizona is about 7,600,000 acre-feet annually of which about 87% is used for agriculture.

  9. Careers in Geothermal Energy: Power from below

    ERIC Educational Resources Information Center

    Liming, Drew

    2013-01-01

    In the search for new energy resources, scientists have discovered ways to use the Earth itself as a valuable source of power. Geothermal power plants use the Earth's natural underground heat to provide clean, renewable energy. The geothermal energy industry has expanded rapidly in recent years as interest in renewable energy has grown. In 2011,…

  10. 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.

  11. Geothermal Energy Potential in Western United States

    ERIC Educational Resources Information Center

    Pryde, Philip R.

    1977-01-01

    Reviews types of geothermal energy sources in the western states, including hot brine systems and dry steam systems. Conversion to electrical energy is a major potential use of geothermal energy, although it creates environmental disruptions such as noise, corrosion, and scaling of equipment. (AV)

  12. 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

  13. Process applications for geothermal energy resources. Final report

    SciTech Connect

    Mikic, B.B.; Meal, H.C.; Packer, M.B.; Guillamon-Duch, H.

    1981-08-01

    The principal goal of the program was to demonstrate economical and technical suitability of geothermal energy as a source of industrial process heat through a cooperative program with industrial firms. To accomplish that: a critical literature survey in the field was performed; a workshop with the paper and pulp industry representatives was organized; and four parallel methods dealing with technical and economical details of geothermal energy use as a source of industrial process heat were developed.

  14. 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.

  15. Reservoir engineering of Wairakei geothermal field

    SciTech Connect

    Grant, Malcom A.

    1988-01-01

    Wairakei was the first liquid dominated geothermal field exploited for major power production. As such many decisions were taken on an ad-hoc or experimental basis. In retrospect the choice of Wairakei was fortunate : with extensive shallow high permeability and major recharge it is an easy field to exploit. This lecture describes the history of the field and the contribution of reservoir engineering to field management, and describes the reservoir as it is now understood.

  16. A database for the Geysers geothermal field

    SciTech Connect

    Ripperda, M.; Bodvarsson, G.S.

    1988-10-01

    A general use menu driven software package has been developed that stores and retrieves geothermal field data and produces a large variety of graphic displays. These include, for example, production plots, cross-sections, contour plots, base maps and Horner plots. This software package has been applied to the Geysers geothermal field which has open file data for over 200 wells. The data include production histories, directional surveys, lithology logs, wellhead temperatures and pressures, digitized base maps, steam entry locations, casing diagrams, pressure transient tests, heat flow measurements and noncondensible gas concentrations. Although the software was developed for use with data from the Geysers, it can be used with data from any geothermal reservoir. 2 refs., 5 figs.

  17. 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)

  18. Hot Topics! Heat Pumps and Geothermal Energy

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2009-01-01

    The recent rapid rises in the cost of energy has significantly increased interest in alternative energy sources. The author discusses the underlying principles of heat pumps and geothermal energy. Related activities for technology education students are included.

  19. The utility of geothermal energy on Mars

    NASA Astrophysics Data System (ADS)

    Fogg, Martyn J.

    1997-01-01

    The exploitation of geothermal energy has been absent from previous considerations of providing power for settlements on Mars. The reason for this is the prevailing paradigm that places all of Mars' volcanic activity in the remote past and hence postulates a crust that is frozen to great depths. It is argued in this paper that this view may be true in general, but false in particular. Geological evidence is reviewed that suggests that magmatism may have been active on Mars until recent times and may hence still be ongoing. Thus, the presence of significant, localized, hyperthermal areas cannot be ruled out on the basis of the low mean heat flows predicted by global heat flow models. The possibility of the presence of useful geothermal fields is further strengthened by observations of fluvial outflows that seem to have been associated with certain magmatic extrusions and which therefore hint at favorable groundwater conditions. Such a geothermal energy source would be of great potential economic value, being of use for the generation of electricity and direct heating for industry and habitation.

  20. THE FUTURE OF GEOTHERMAL ENERGY

    SciTech Connect

    J. L. Renner

    2006-11-01

    Recent national focus on the value of increasing our supply of indigenous, renewable energy underscores the need for reevaluating all alternatives, particularly those that are large and welldistributed nationally. This analysis will help determine how we can enlarge and diversify the portfolio of options we should be vigorously pursuing. One such option that is often ignored is geothermal energy, produced from both conventional hydrothermal and Enhanced (or engineered) Geothermal Systems (EGS). An 18-member assessment panel was assembled in September 2005 to evaluate the technical and economic feasibility of EGS becoming a major supplier of primary energy for U.S. base-load generation capacity by 2050. This report documents the work of the panel at three separate levels of detail. The first is a Synopsis, which provides a brief overview of the scope, motivation, approach, major findings, and recommendations of the panel. At the second level, an Executive Summary reviews each component of the study, providing major results and findings. The third level provides full documentation in eight chapters, with each detailing the scope, approach, and results of the analysis and modeling conducted in each area.

  1. The Hydrogeochemistry of Qingshui Geothermal Field, Northeastern Taiwan.

    NASA Astrophysics Data System (ADS)

    Yu-Wen, Chen; Cheng-Kuo, Lin; Wayne, Lin; Yu-Te, Chang; Pei-Shan, Hsieh

    2015-04-01

    The Qingshui geothermal field is located at the upstream valley of Lanyang Creek, northeastern Taiwan. It is renowned as a geothermal field. The previous studies demonstrated a higher geothermal gradient, 100oC/km warmer than a normal geotherm. However, Qingshui geothermal field has not been well developed due to the higher mining costs. In the recent years, the Taiwan government has been focusing on developing alternative and renewable energy and initiated a 10 year project, Nation Energy Program. This study is part of this project In general, it is very difficult to collect deep downhole samples without considerable change of hydro- and gas- chemistry of water under high temperature and pressure. A new sampling tool, GTF Sampler, was designed by the research team, Green Energy and Environment Laboratories, Industrial Technology Research Institute. This tool can simultaneously collect high quality geothermal water and gas sample and moreover, the sampling depth can reach up to 800 meters. Accordingly, a more accurate measurements can be conducted in the laboratory. In this study, 10 geothermal samples were collected and measured. The results demonstrate that geothermal water samples are characterized with Na(K)-HCO3 water type and located at the mature water area in Giggenbach Na-K-Mg diagram. Several geothermometers, including silica and cation geothermometry, were used to estimate potential temperature in the geothermal reservoir systems. In general, the geothermoters of Na-K and Na-K-Ca obtain reservoir temperatures between 120-190oC and 130-210oC, respectively, but the silica geothermometer indicates a lower reservoir temperature between 90 and 170oC. There is no big difference among them. It is worth to note that all calculated temperatures are lower than those of in-situ downhole measurements; therefore, more detailed and advanced researches would be needed for the inconsistency. To examine the argument about igneous heat source in the previous studies, rare

  2. Geothermal Field Development in Mexico

    SciTech Connect

    Espinosa, Hector Alonso

    1983-12-15

    Mexico is a Country characterized by its diversified means of Power Gerneration. Actual installed capacity is almost 19000 MW, of which 205 MW corresponds to Geothermal Plants, that is, 180 MW in Cerro Prieto and 25 MW of Portable Plants in Los Azufres. To date, 346 area with exploitation possibilites, are known. They are mainly distributed along the Volcanic Belt where the most prominent are, Los Azufres, La Primavera, Los Humeros, Ixtlan De Los Hervores and Los Negritos, among others. Proved reserves are 920 MW, and the accessible resource base are 4600 MW identified and 6000 MW undiscovered. The long range construction studies intends to achieve a total installed capacity of 100000 MW, by the end of this century, including 2000 MW Geothermal, through conventional and Portable Plants. It is not a definite program but a development strategy. The carrying out of a definite program, will depend upon the confirmation of Hypothesis made in previous studies, and the economic decisions related to the financial sources availability, and techologies to be used in the future as well.

  3. Ground Energy Balance For Shallow Geothermal Systems

    NASA Astrophysics Data System (ADS)

    Bayer, P.; Rivera, J.

    2015-12-01

    Vertical borehole heat exchangers (BHE) represent the most common applications by far in the field of shallow geothermal energy. They are typically operated for decades for energy extraction from the top 400 m of the subsurface. During this lifetime, thermal anomalies are generated in the ground and surface-near aquifers. These anomalies often grow over the years and compromise the overall performance of the geothermal system. As a basis for prediction and control of the developing energy imbalance in the ground, the focus is often set on the ground temperatures. This is reflected, for instance, in regulative temperature thresholds. As an alternative to temperature, we examine the temporal and spatial variability of heat fluxes and power sources during geothermal heat pump operation. The underlying idea is that knowledge of the primary heat sources is fundamental for the control of ground temperature evolution. For analysis of heat fluxes, an analytical framework for BHE simulation based on Kelvin's line source is re-formulated. This is applied to a synthetic study and for modelling a long-term application in the field. Our results show that during early operation phase, energy is extracted mainly from the underground. Local depletion at the borehole enhances the vertical fluxes with the relative contribution from the bottom reaching a limit of 24 % of the total power demand. The relative contribution from the ground surface becomes dominant for Fourier numbers larger than 0.13. For the full life cycle, vertical heat flux from the ground surface dominates the basal heat flux towards the BHE and it provides about two thirds of the demanded power. Finally, we reveal that the time for ground energy recovery after BHE shutdown may be longer than what is expected from simulated temperature trends.

  4. Cerro Prieto geothermal field: exploration during exploitation

    SciTech Connect

    Not Available

    1982-07-01

    Geological investigations at Momotombo included photogeology, field mapping, binocular microscope examination of cuttings, and drillhole correlations. Among the geophysical techniques used to investigate the field sub-structure were: Schlumberger and electromagnetic soundings, dipole mapping and audio-magnetotelluric surveys, gravity and magnetic measurements, frequency domain soundings, self-potential surveys, and subsurface temperature determinations. The geochemical program analyzed the thermal fluids of the surface and in the wells. The description and results of exploration methods used during the investigative stages of the Momotombo Geothermal Field are presented. A conceptual model of the geothermal field was drawn from the information available at each exploration phase. The exploration methods have been evaluated with respect to their contributions to the understanding of the field and their utilization in planning further development.

  5. Relative Contributions of Geothermal Pumping and Long-Term Earthquake Rate to Seismicity at California Geothermal Fields

    NASA Astrophysics Data System (ADS)

    Weiser, D. A.; Jackson, D. D.

    2015-12-01

    In a tectonically active area, a definitive discrimination between geothermally-induced and tectonic earthquakes is difficult to achieve. We focus our study on California's 11 major geothermal fields: Amedee, Brawley, Casa Diablo, Coso, East Mesa, The Geysers, Heber, Litchfield, Salton Sea, Susanville, and Wendel. The Geysers geothermal field is the world's largest geothermal energy producer. California's Department of Oil Gas and Geothermal Resources provides field-wide monthly injection and production volumes for each of these sites, which allows us to study the relationship between geothermal pumping activities and seismicity. Since many of the geothermal fields began injecting and producing before nearby seismic stations were installed, we use smoothed seismicity since 1932 from the ANSS catalog as a proxy for tectonic earthquake rate. We examine both geothermal pumping and long-term earthquake rate as factors that may control earthquake rate. Rather than focusing only on the largest earthquake, which is essentially a random occurrence in time, we examine how M≥4 earthquake rate density (probability per unit area, time, and magnitude) varies for each field. We estimate relative contributions to the observed earthquake rate of M≥4 from both a long-term earthquake rate (Kagan and Jackson, 2010) and pumping activity. For each geothermal field, respective earthquake catalogs (NCEDC and SCSN) are complete above at least M3 during the test period (which we tailor to each site). We test the hypothesis that the observed earthquake rate at a geothermal site during the test period is a linear combination of the long-term seismicity and pumping rates. We use a grid search to determine the confidence interval of the weighting parameters.

  6. Geothermal Energy Information Dissemination and Outreach

    SciTech Connect

    Dr. John W. Lund

    2005-12-31

    The objective of this project is to continue on-going work by the Geo-Heat Center to develop and disseminate information; provide educational materials; develop short courses and workshops; maintain a comprehensive geothermal resource database; respond to inquiries from the public, industry and government; provide engineering, economic and environmental information and analysis on geothermal technology to potential users and developers; and provide information on market opportunities for geothermal development. These efforts are directed towards increasing the utilization of geothermal energy in the US and developing countries, by means of electric power generation and direct-use.

  7. Department of Energy--Office of Energy Efficiency and Renewable Energy Geothermal Program: Geothermal Risk Mitigation Strategies Report

    SciTech Connect

    None, None

    2008-02-15

    An overview of general financial issues for renewable energy investments; geothermal energy investment barriers and risks; and recommendations for incentives and instruments to be considered to stimulate investment in geothermal energy development.

  8. Geothermally Coupled Well-Based Compressed Air Energy Storage

    SciTech Connect

    Davidson, C L; Bearden, Mark D; Horner, Jacob A; Appriou, Delphine; McGrail, B Peter

    2015-12-01

    Previous work by McGrail et al. (2013, 2015) has evaluated the possibility of pairing compressed air energy storage with geothermal resources in lieu of a fossil-fired power generation component, and suggests that such applications may be cost competitive where geology is favorable to siting both the geothermal and CAES components of such a system. Those studies also note that the collocation of subsurface resources that meet both sets of requirements are difficult to find in areas that also offer infrastructure and near- to mid-term market demand for energy storage. This study examines a novel application for the compressed air storage portion of the project by evaluating the potential to store compressed air in disused wells by amending well casings to serve as subsurface pressure vessels. Because the wells themselves would function in lieu of a geologic storage reservoir for the CAES element of the project, siting could focus on locations with suitable geothermal resources, as long as there was also existing wellfield infrastructure that could be repurposed for air storage. Existing wellfields abound in the United States, and with current low energy prices, many recently productive fields are now shut in. Should energy prices remain stagnant, these idle fields will be prime candidates for decommissioning unless they can be transitioned to other uses, such as redevelopment for energy storage. In addition to the nation’s ubiquitous oil and gas fields, geothermal fields, because of their phased production lifetimes, also may offer many abandoned wellbores that could be used for other purposes, often near currently productive geothermal resources. These existing fields offer an opportunity to decrease exploration and development uncertainty by leveraging data developed during prior field characterization, drilling, and production. They may also offer lower-cost deployment options for hybrid geothermal systems via redevelopment of existing well-field infrastructure

  9. Geothermally Coupled Well-Based Compressed Air Energy Storage

    SciTech Connect

    Davidson, Casie L.; Bearden, Mark D.; Horner, Jacob A.; Cabe, James E.; Appriou, Delphine; McGrail, B. Peter

    2015-12-20

    Previous work by McGrail et al. (2013, 2015) has evaluated the possibility of pairing compressed air energy storage with geothermal resources in lieu of a fossil-fired power generation component, and suggests that such applications may be cost competitive where geology is favorable to siting both the geothermal and CAES components of such a system. Those studies also note that the collocation of subsurface resources that meet both sets of requirements are difficult to find in areas that also offer infrastructure and near- to mid-term market demand for energy storage. This study examines a novel application for the compressed air storage portion of the project by evaluating the potential to store compressed air in disused wells by amending well casings to serve as subsurface pressure vessels. Because the wells themselves would function in lieu of a geologic storage reservoir for the CAES element of the project, siting could focus on locations with suitable geothermal resources, as long as there was also existing wellfield infrastructure that could be repurposed for air storage. Existing wellfields abound in the United States, and with current low energy prices, many recently productive fields are now shut in. Should energy prices remain stagnant, these idle fields will be prime candidates for decommissioning unless they can be transitioned to other uses, such as redevelopment for energy storage. In addition to the nation’s ubiquitous oil and gas fields, geothermal fields, because of their phased production lifetimes, also may offer many abandoned wellbores that could be used for other purposes, often near currently productive geothermal resources. These existing fields offer an opportunity to decrease exploration and development uncertainty by leveraging data developed during prior field characterization, drilling, and production. They may also offer lower-cost deployment options for hybrid geothermal systems via redevelopment of existing well-field infrastructure

  10. Heat-flow mapping at the Geysers Geothermal Field

    SciTech Connect

    Thomas, R.P.

    1986-10-31

    Pertinent data were compiled for 187 temperature-gradient holes in the vicinity of The Geysers Geothermal field. Terrain-correction techniques were applied to most of the temperature-gradient data, and a temperature-gradient map was constructed. Cutting samples from 16, deep, production wells were analyzed for thermal conductivity. From these samples, the mean thermal conductivities were determined for serpentinized ultramafic rock, greenstone, and graywacke. Then, a heat flow map was made. The temperature-gradient and heat-flow maps show that The Geysers Geothermal field is part of a very large, northwesterly-trending, thermal anomaly; the commercially productive portion of the field may be 100 km/sup 2/ in area. The rate that heat energy flows through the surface by thermal conduction is estimated at 1.79 x 10/sup 9/MJ per year. The net heat energy loss from commercial production for 1983 is estimated at 180.14 x 10/sup 9/MJ.

  11. 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.

  12. 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.

  13. The Los Azufres, Michoacan, Mexico, geothermal field

    NASA Astrophysics Data System (ADS)

    Gutierrez N., Augusto; Aumento, Fabrizio

    1982-03-01

    Fifteen deep exploratory and production wells in a 30-km 2 area have permitted the study of both the primary igneous petrology and the secondary geothermal system and its associated mineralization. The Los Azufres field lies on a complex Plio-Pleistocene succession of basalts, andesites, dacites and rhyolites, each with its associated tuffs. Recently, alkali basalt magmas have intruded the area, extruding minor lava flows. Geothermal fluids have altered all the above rocks from a minimum of 20% of the total rock volume, to a maximum of 100%, with an average 75% alteration. Multiple distinct zones of oxides, clay minerals, chlorites, calcite, quartz and epidote are discernible, together with minor amphiboles, zeolites and pyrite. There appear to have been two distinct heat sources, the first associated with the youngest rhyolitic extrusives, whilst the second, current heat source, at a considerably greater depth, may be due to a new, more basic magmatic cycle. This downward displacement is associated with a lateral, northeasterly migration of the heat source. Both geothermal systems were accompanied by temporary escapes of hot fluids along fault planes at different localities at different times, which produced localized, anomalous heat fluxes with associated mineralization superimposed onto the regional geothermal pattern.

  14. Reservoir assessment of The Geysers Geothermal field

    SciTech Connect

    Thomas, R.P.; Chapman, R.H.; Dykstra, H.

    1981-01-01

    Big Sulphur Creek fault zone, in The Geysers Geothermal field, may be part of a deep-seated, wrench-style fault system. Hydrothermal fluid in the field reservoir may rise through conduits beneath the five main anomalies associated with the Big Sulphur Creek wrench trend. Some geophysical anomalies (electrical resistivity and audio-magnetotelluric) evidently are caused by the hot water geothermal field or zones of altered rocks; others (gravity, P-wave delays, and possibly electrical resistivity) probably respresent the underlying heat source, a possible magma chamber; and others (microearthquake activity) may be related to the steam reservoir. A large negative gravity anomaly and a few low-resistivity anomalies suggest areas generally favorable for the presence of steam zones, but these anomalies apparently do not directly indicate the known steam reservoir. At the current generating capacity of 930 MWe, the estimated life of The Geysers Geothermal field reservoir is 129 years. The estimated reservoir life is 60 years for the anticipated maximum generating capacity of 2000 MWe as of 1990. Wells at The Geysers are drilled with conventional drilling fluid (mud) until the top of the steam reservoir is reached; then, they are drilled with air. Usually, mud, temperature, caliper, dual induction, and cement bond logs are run on the wells.

  15. Modeling of geothermal reservoirs: Fundamental processes, computer simulation, and field applications

    SciTech Connect

    Pruess, K.

    1988-09-01

    This article attempts to critically evaluate the present state of the art of geothermal reservoir simulation. Methodological aspects of geothermal reservoir modeling are briefly reviewed, with special emphasis on flow in fractured media. Then we examine applications of numerical simulation to studies of reservoir dynamics, well test design and analysis, and modeling of specific fields. Tangible impacts of reservoir simulation technology on geothermal energy development are pointed out. We conclude with considerations on possible future developments in the mathematical modeling of geothermal fields. 45 refs., 4 figs., 2 tabs.

  16. 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.

  17. Geothermal energy development in the Philippines: An overview

    SciTech Connect

    Sussman, D.; Javellana, S.P.; Benavidez, P.J.

    1993-10-01

    The Philippines is the third largest producer of geothermal electricity after the US and Mexico. Geothermal exploration was started in 1962, and the first large commercial power plants came on-line in 1979 in two fields. By 1984, four geothermal fields had a combined installed capacity of 890 MWe and in 1992 these plants supplied about 20% of the country`s electric needs. Geothermal energy development was stimulated in the mid-1970s by the oil crisis and rapidly growing power demand, government support, available foreign funding, and a combination of private and government investment and technical expertise. However, no new geothermal capacity has been added since 1984, despite the growing demand for energy and the continuing uncertainty in the supply of crude oil. The Philippines` geothermal capacity is expected to expand by 270--1,100 MWe by the end of 1999. Factors that will affect the rate growth in this decade include suitable legislation, environmental requirements, financing, degree of private involvement, politics, inter-island electric grid connections, and viability of the remaining prospects.

  18. Technical databook for geothermal energy utilization

    SciTech Connect

    Phillips, S.L.; Igbene, A.; Fair, J.A.; Ozbek, H.; Tavana, M.

    1981-06-01

    A critical survey is made of selected basic data on those aqueous solutions needed to model geothermal energy utilization. The data are useful in the design and construction of power plants and for direct use. The result of the survey is given as a current status of data. More emphasis is placed on the viscosity, thermal conductivity and density of sodium chloride solutions up to 350/sup 0/C and 50 MPa. An ideal data book for geothermal energy is described.

  19. 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.

  20. Extremely Shallow Extensional Faulting Near Geothermal Fields

    NASA Astrophysics Data System (ADS)

    Hudnut, K. W.; Wei, S.; Donnellan, A.; Fielding, E. J.; Graves, R. W.; Helmberger, D. V.; Liu, Z.; Parker, J. W.; Treiman, J. A.

    2013-12-01

    side down slip. Up to 18 cm/s ground motion were observed at four seismic stations within 10 km which are modeled by northward rupture directivity with rupture speed of ~1.0-1.5 km/s. Although most energy in Brawley Seismic Zone swarms is released in deeper and larger strike-slip events, we observe surprisingly that the recent cases of surface faulting in 2005 on the Kalin fault (Rymer et al., USGS OFR 2010-1333) and 2012 preferentially involve normal fault surface slip in close proximity to geothermal fields, as did the 2006 Morelia fault case (Suárez-Vidal et al., SRL 2007). The Aug. 2012 case was the latest of three minor extensional surface ruptures, each associated with moderate seismic activity near geothermal fields. We compare this latest case, with its ~3.5 km surface break, and the two earlier examples with ~0.5 km (2005) and ~2.0 km (2006) long surface breaks with similar NE-SW to NNE-SSW orientations. All three cases had tectonic surface slip of greater than 15 cm but less than 30 cm, involved mostly normal fault slip, and occurred within extensional step-over zones between the San Andreas and Imperial faults (2005 & 2012), and between the Imperial and Cerro Prieto faults (2006).

  1. 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.

  2. FINAL TECHNICAL REPORT, U.S. Department of Energy: Award No. DE-EE0002855 "Demonstrating the Commercial Feasibility of Geopressured-Geothermal Power Development at Sweet Lake Field - Cameron Parish, Louisiana"

    SciTech Connect

    Gayle, Phillip A., Jr.

    2012-01-13

    The goal of the project was to demonstrate the commercial feasibility of geopressured-geothermal power development by exploiting the extraordinarily high pressured hot brines know to exist at depth near the Sweet Lake oil and gas field in Cameron Parish, Louisiana. The existence of a geopressured-geothermal system at Sweet Lake was confirmed in the 1970's and 1980's as part of DOE's Geopressured-Geothermal Program. That program showed that the energy prices at the time could not support commercial production of the resource. Increased electricity prices and technological advancements over the last two decades, combined with the current national support for developing clean, renewable energy and the job creation it would entail, provided the justification necessary to reevaluate the commercial feasibility of power generation from this vast resource.

  3. Washington: a guide to geothermal energy development

    SciTech Connect

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

    1980-01-01

    A brief overview is given of the geological characteristics of each region of the state as they relate to potential geothermal development. Those exploration methods which can lead to the siting of a deep exploration well are described. Requirements and techniques needed for drilling deeper higher temperature exploration and production wells are presented. Electrical generation, direct utilization, and indirect utilization are reviewed. Economic factors of direct use projects are presented. A general guide to the regulatory framework affecting geothermal energy development is provided. The general steps necessary to gain access to explore, develop, distribute, and use geothermal resources are outlined. (MHR)

  4. Oregon: a guide to geothermal energy development

    SciTech Connect

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

    1980-06-01

    A brief overview is given of the geological characteristics of each region of the state as they relate to potential geothermal development. Those exploration methods which can lead to the siting of a deep exploration well are described. Requirements and techniques needed for drilling deeper higher temperature exploration and production wells are presented. Electrical generation, direct utilization, and indirect utilization are reviewed. Economic factors of direct use projects are presented. A general guide to the regulatory framework affecting geothermal energy development is provided. The general steps necessary to gain access to explore, develop, distribute, and use geothermal resources are outlined. (MHR)

  5. Alaska: a guide to geothermal energy development

    SciTech Connect

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

    1980-06-01

    A brief overview is given of the geological characteristics of each region of the state as they relate to potential geothermal development. Those exploration methods which can lead to the siting of a deep exploration well are described. Requirements and techniques needed for drilling deeper higher temperature exploration and production wells are presented. Electrical generation, direct utilization, and indirect utilization are reviewed. Economic factors of direct use projects are presented. A general guide to the regulatory framework affecting geothermal energy development is provided. The general steps necessary to gain access to explore, develop, distribute, and use geothermal resources are outlined. (MHR)

  6. Tapping the main stream of geothermal energy

    NASA Astrophysics Data System (ADS)

    1980-09-01

    The development of geothermal energy resources in the United States is discussed. The distribution of underground water resources at temperatures above 90 C and depths up to 3 km in the continental U.S. is examined, and it is pointed out that whereas geothermal resources have been detected under 24 states, only 220 quadrillion Btu of energy recoverable as 24 GW of electricity for 30 years has been conclusively located, all of it in the western states. Direct-flash technology, which generates electricity from hydrothermal fluid at a temperature above 210 C with an efficiency of 15% is presented, and the binary cycle technology required to generate electricity from lower-temperature fluids such as those in the 180 C reservoir of low-salinity brine at Heber in southern California is examined in detail. Questions of minerals and heat control in a geothermal turbine system and the environmental emissions from geothermal plants are addressed. The geothermal resources of the United States are classified as petrothermal, geopressurized and hydrothermal, and methods for extracting heat from these dry rocks, pressurized water and natural gas deposits and systems of steam and hot water are indicated. It is concluded that as fossil fuel energy costs rise, the trend favors geothermal energy, particularly that which can be developed from known hydrothermal resources

  7. Turkey's High Temperature Geothermal Energy Resources and Electricity Production Potential

    NASA Astrophysics Data System (ADS)

    Bilgin, Ö.

    2012-04-01

    Turkey is in the first 7 countries in the world in terms of potential and applications. Geothermal energy which is an alternative energy resource has advantages such as low-cost, clean, safe and natural resource. Geothermal energy is defined as hot water and steam which is formed by heat that accumulated in various depths of the Earth's crust; with more than 20oC temperature and which contain more than fused minerals, various salts and gases than normal underground and ground water. It is divided into three groups as low, medium and high temperature. High-temperature fluid is used in electricity generation, low and medium temperature fluids are used in greenhouses, houses, airport runways, animal farms and places such as swimming pools heating. In this study high temperature geothermal fields in Turkey which is suitable for electricity production, properties and electricity production potential was investigated.

  8. Geology of the Olkaria Geothermal Field

    SciTech Connect

    Ogoso-Odongo, M.E.

    1986-01-01

    Up to now development of the resource in Olkaria geothermal field, Kenya, has been based on fragmental information that is inconclusive in most respects. Development has been concentrated in an area of 4 km/sup 2/ at most, with well to well spacing of less than 300 m. The move now is to understand the greater Olkaria field by siting exploratory wells in different parts of the area considered of reasonable potential. To correlate the data available from the different parts of the field, the geology of the area, as a base for the composite field model, is discussed and shown to have major controls over fluid movements in the area and other features.

  9. International Legislation of Shallow Geothermal Energy Use

    NASA Astrophysics Data System (ADS)

    Hähnlein, S.; Bayer, P.; Blum, P.

    2009-12-01

    Climate change, energy savings and energy autonomy are frequently discussed topics. Hence, renewable energy resources are currently promoted worldwide. One of these is geothermal energy. Worldwide the number of shallow geothermal installations (< 400 m depth) is continuously rising. One consequence is widespread man-made temperature anomalies in natural aquifer systems. These have to be controlled to guarantee long-term usability of the geothermal reservoirs and to avoid adverse effects on groundwater ecosystems. However, nationally as well as internationally, regulations to achieve these controls are very heterogeneous, sometimes contradictory and scientifically questionable. For example, what is the optimal distance between adjacent, potentially competing ground source heat pump (GSHP) or groundwater heat pump (GWHP) systems? Answers to derive a good code of practice have to balance technical, economic and ecological criteria. The objective of our study is to review the current international legal status of thermal use of groundwater. We present the results of an international survey, which offers comprehensive insight in the worldwide legal situation of closed and open systems of shallow geothermal installations. The focus is on minimum distances of these systems and limits for groundwater temperature changes. We can conclude that there are only few regulations and recommendations for minimum distances of these installations and groundwater temperature changes. Some countries have no regulations and in addition if recommendations are given, these are not legally binding. However, to promote shallow geothermal energy as an economically attractive and sustainable energy source, an international homogeneous legislation is necessary.

  10. Geothermal Energy Development in the Eastern United States, Sensitivity analysis-cost of geothermal energy

    SciTech Connect

    Kane, S.M.; Kroll, P.; Nilo, B.

    1982-12-01

    The Geothermal Resources Interactive Temporal Simulation (GRITS) model is a computer code designed to estimate the costs of geothermal energy systems. The interactive program allows the user to vary resource, demand, and financial parameters to observe their effects on delivered costs of direct-use geothermal energy. Due to the large number and interdependent nature of the variables that influence these costs, the variables can be handled practically only through computer modeling. This report documents a sensitivity analysis of the cost of direct-use geothermal energy where each major element is varied to measure the responsiveness of cost to changes in that element. It is hoped that this analysis will assist those persons interested in geothermal energy to understand the most significant cost element as well as those individuals interested in using the GRITS program in the future.

  11. Deep drilling for geothermal energy in Finland

    NASA Astrophysics Data System (ADS)

    Kukkonen, Ilmo

    2016-04-01

    There is a societal request to find renewable CO2-free energy resources. One of the biggest such resources is provided by geothermal energy. In addition to shallow ground heat already extensively used in Finland, deep geothermal energy provides an alternative so far not exploited. Temperatures are high at depth, but the challenge is, how to mine the heat? In this presentation, the geological and geophysical conditions for deep geothermal energy production in Finland are discussed as well as challenges for drilling and conditions at depth for geothermal energy production. Finland is located on ancient bedrock with much lower temperatures than geologically younger volcanically and tectonically active areas. In order to reach sufficiently high temperatures drilling to depths of several kilometres are needed. Further, mining of the heat with, e.g., the principle of Enhanced Geothermal System (EGS) requires high hydraulic conductivity for efficient circulation of fluid in natural or artificial fractures of the rock. There are many issues that must be solved and/or improved: Drilling technology, the EGS concept, rock stress and hydraulic fracturing, scale formation, induced seismicity and ground movements, possible microbial activity, etc. An industry-funded pilot project currently in progress in southern Finland is shortly introduced.

  12. Future Technologies to Enhance Geothermal Energy Recovery

    SciTech Connect

    Roberts, J J; Kaahaaina, N; Aines, R; Zucca, J; Foxall, B; Atkins-Duffin, C

    2008-07-25

    Geothermal power is a renewable, low-carbon option for producing base-load (i.e., low-intermittency) electricity. Improved technologies have the potential to access untapped geothermal energy sources, which experts estimate to be greater than 100,000 MWe. However, many technical challenges in areas such as exploration, drilling, reservoir engineering, and energy conversion must be addressed if the United States is to unlock the full potential of Earth's geothermal energy and displace fossil fuels. (For example, see Tester et al., 2006; Green and Nix, 2006; and Western Governors Association, 2006.) Achieving next-generation geothermal power requires both basic science and applied technology to identify prospective resources and effective extraction strategies. Lawrence Livermore National Laboratory (LLNL) has a long history of research and development work in support of geothermal power. Key technologies include advances in scaling and brine chemistry, economic and resource assessment, direct use, exploration, geophysics, and geochemistry. For example, a high temperature, multi-spacing, multi-frequency downhole EM induction logging tool (GeoBILT) was developed jointly by LLNL and EMI to enable the detection and orientation of fractures and conductive zones within the reservoir (Figure 1). Livermore researchers also conducted studies to determine how best to stave off increased salinity in the Salton Sea, an important aquatic ecosystem in California. Since 1995, funding for LLNL's geothermal research has decreased, but the program continues to make important contributions to sustain the nation's energy future. The current efforts, which are highlighted in this report, focus on developing an Engineered Geothermal System (EGS) and on improving technologies for exploration, monitoring, characterization, and geochemistry. Future research will also focus on these areas.

  13. Changes in thermal activity in the Rotorua geothermal field

    SciTech Connect

    Cody, A.D. ); Lumb, J.T. )

    1992-04-01

    During a period when geothermal fluid was being withdrawn for energy use at an increasing rate, the level of natural hydrothermal activity in the Rotorua geothermal field declined in an all-time low in the mid 1980s. total heatflow from a major hot-spring area fell by almost 50 percent, springs ceased their flow, and geysers displayed abnormal behavior consistent with a low aquifer pressure. since the enforced closure of bores within 1.5 km of Pohutu Geyser, sings of recovery, including a return to normal behavior of Pohutu and Waikorohihi Geysers, a resumption of activity at Kereru Geyser, and an increase in water flow from some springs are presented in this paper.

  14. Performance of deep geothermal energy systems

    NASA Astrophysics Data System (ADS)

    Manikonda, Nikhil

    Geothermal energy is an important source of clean and renewable energy. This project deals with the study of deep geothermal power plants for the generation of electricity. The design involves the extraction of heat from the Earth and its conversion into electricity. This is performed by allowing fluid deep into the Earth where it gets heated due to the surrounding rock. The fluid gets vaporized and returns to the surface in a heat pipe. Finally, the energy of the fluid is converted into electricity using turbine or organic rankine cycle (ORC). The main feature of the system is the employment of side channels to increase the amount of thermal energy extracted. A finite difference computer model is developed to solve the heat transport equation. The numerical model was employed to evaluate the performance of the design. The major goal was to optimize the output power as a function of parameters such as thermal diffusivity of the rock, depth of the main well, number and length of lateral channels. The sustainable lifetime of the system for a target output power of 2 MW has been calculated for deep geothermal systems with drilling depths of 8000 and 10000 meters, and a financial analysis has been performed to evaluate the economic feasibility of the system for a practical range of geothermal parameters. Results show promising an outlook for deep geothermal systems for practical applications.

  15. Pilot fruit drier for Los Azufres geothermal field, Michoacan, Mexico

    SciTech Connect

    Lund, J.W.

    1993-02-01

    Comision Federal de Electricidad (CFE) has a Division in charge of the exploration of a geothermal reservoir located in Los Azufres, State of Michoacan. At present, CFE is only using the steam of the wells and rejecting the hot water that comes off associated with the steam. Based on a trip to the Los Azufres geothermal field in December of 1992, a design for a pilot geothermal fruit drier was undertaken for CFE. The details of the geothermal field and the local fruit production are detailed.

  16. Overview of the Geothermal Energy Program Review X: Geothermal Energy and the Utility Market - The Opportunities and Challenges for Expanding Geothermal Energy in a Competitive Supply Market

    SciTech Connect

    Mock, John E.; Budraja, Vikram; Jaros, Richard; Yamaguchi, Tsutomu; Hinrichs, Thomas C.

    1992-01-01

    This overview at the Geothermal Program Review X: Geothermal Energy and the Utility Market consisted of five presentations: ''Technology Advancements to Support Growth in Geothermal Power Sales in a Dynamic Utility Market'' by John E. Mock; ''Geothermal Energy Market in Southern California: Past, Present and Future'' by Vikram Budraja; ''Taking the High Ground: Geothermal's Place in the Revolving Energy Market'' by Richard Jaros; ''Recent Developments in Japan's Hot Dry Rock Program'' by Tsutomu Yamaguchi; and ''Options in the Eleventh Year for Interim Standard Offer Number Four Contracts'' by Thomas C. Hinrichs.

  17. Geothermal energy production with supercritical fluids

    DOEpatents

    Brown, Donald W.

    2003-12-30

    There has been invented a method for producing geothermal energy using supercritical fluids for creation of the underground reservoir, production of the geothermal energy, and for heat transport. Underground reservoirs are created by pumping a supercritical fluid such as carbon dioxide into a formation to fracture the rock. Once the reservoir is formed, the same supercritical fluid is allowed to heat up and expand, then is pumped out of the reservoir to transfer the heat to a surface power generating plant or other application.

  18. Fairbanks Geothermal Energy Project Final Report

    SciTech Connect

    Karl, Bernie

    2013-05-31

    The primary objective for the Fairbanks Geothermal Energy Project is to provide another source of base-load renewable energy in the Fairbanks North Star Borough (FNSB). To accomplish this, Chena Hot Springs Resort (Chena) drilled a re-injection well to 2700 feet and a production well to 2500 feet. The re-injection well allows a greater flow of water to directly replace the water removed from the warmest fractures in the geothermal reservoir. The new production will provide access to warmer temperature water in greater quantities.

  19. The Geysers Geothermal Field Update1990/2010

    SciTech Connect

    Brophy, P.; Lippmann, M.; Dobson, P.F.; Poux, B.

    2010-10-01

    all technical fields, as related to The Geysers steam-dominated geothermal system. The Geysers has seen many fundamental changes between 1990-2010 and yet the geothermal resource seems still to be robust to the extent that, long after its anticipated life span, we are seeing new geothermal projects being developed on the north and west peripheries of the field. It is hoped that this report provides a focused data source particularly for those just starting their geothermal careers, as well as those who have been involved in the interesting and challenging field of geothermal energy for many years. Despite many hurdles The Geysers has continued to generate electrical power for 50 years and its sustainability has exceeded many early researchers expectations. It also seems probable that, with the new projects described above, generation will continue for many years to come. The success of The Geysers is due to the technical skills and the financial acumen of many people, not only over the period covered by this report (1990-2010), but since the first kilowatt of power was generated in 1960. This Special Report celebrates those 50 years of geothermal development at The Geysers and attempts to document the activities that have brought success to the project so that a permanent record can be maintained. It is strongly hoped and believed that a publication similar to this one will be necessary in another 20 years to document further activities in the field.

  20. 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.

  1. Geothermal energy for copper dump leaching

    SciTech Connect

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

    1982-08-01

    This report evaluates the possibility of using geothermal energy to heat a sulfuric acid leaching solution for the purpose of faster and more efficient copper recovery from copper-containing minerals. Experimental studies reported in the literature have shown that this technique can be economically feasible for the extraction of copper from low-grade dump ores. Its main advantage appears to be the considerable reduction in long-term leaching periods; it could also be less expensive than other conventional processing operations if an economical geothermal resource were provided. However, this process has some pitfalls which might restrict the extent of geothermal energy use. Nevertheless, the process is still technologically sound, especially if groundwaters are used directly in the leaching operation.

  2. Structural investigations of Great Basin geothermal fields: Applications and implications

    SciTech Connect

    Faulds, James E; Hinz, Nicholas H.; Coolbaugh, Mark F

    2010-11-01

    Because fractures and faults are commonly the primary pathway for deeply circulating hydrothermal fluids, structural studies are critical to assessing geothermal systems and selecting drilling targets for geothermal wells. Important tools for structural analysis include detailed geologic mapping, kinematic analysis of faults, and estimations of stress orientations. Structural assessments are especially useful for evaluating geothermal fields in the Great Basin of the western USA, where regional extension and transtension combine with high heat flow to generate abundant geothermal activity in regions having little recent volcanic activity. The northwestern Great Basin is one of the most geothermally active areas in the USA. The prolific geothermal activity is probably due to enhanced dilation on N- to NNE-striking normal faults induced by a transfer of NW-directed dextral shear from the Walker Lane to NW-directed extension. Analysis of several geothermal fields suggests that most systems occupy discrete steps in normal fault zones or lie in belts of intersecting, overlapping, and/or terminating faults. Most fields are associated with steeply dipping faults and, in many cases, with Quaternary faults. The structural settings favoring geothermal activity are characterized by subvertical conduits of highly fractured rock along fault zones oriented approximately perpendicular to the WNW-trending least principal stress. Features indicative of these settings that may be helpful in guiding exploration for geothermal resources include major steps in normal faults, interbasinal highs, groups of relatively low discontinuous ridges, and lateral jogs or terminations of mountain ranges.

  3. Geothermal Energy Program Summary Document, FY 1982

    SciTech Connect

    1981-01-01

    Geothermal energy is derived from the internal heat of the earth. Much of it is recoverable with current or near current technology. Geothermal energy can be used for electric power production, residential and commercial space heating and cooling, industrial process heat, and agricultural applications. Three principal types of geothermal resources are exploitable through the year 2000. In order of technology readiness, these resources are: hydrothermal; geopressured (including dissolved natural gas); and hot dry rock. In hydrothermal systems, natural water circulation moves heat from deep internal sources toward the earth's surface. Geothermal fluids (water and steam) tapped by drilling can be used to generate electricity or provide direct heat. Geopressured resources, located primarily in sedimentary basins along the Gulf Coast of Texas and of Louisiana, consist of water and dissolved methane at high pressure and at moderately high temperature. In addition to recoverable methane, geopressured resources provide thermal energy and mechanical energy derived from high fluid pressures, although methane offers the greatest immediate value. Commercial development of geopressured energy may begin in the mid-1980s. Economic feasibility depends on the amount of methane that a given well can produce, a highly uncertain factor at present.

  4. Geothermal energy market study on the Atlantic Coastal Plain: Ocean City, Maryland geothermal energy evaluation

    SciTech Connect

    Schubert, C.E.

    1981-08-01

    This report is one of a series of studies that have been made by the Applied Physics Laboratory, or its subcontractors, to examine the technical and economic feasibility of the utilization of geothermal energy at the request of potential users.

  5. Seismic monitoring at the Geysers Geothermal Field

    SciTech Connect

    Romero, A.E. Jr.; Kirkpatrick, A.; Majer, E.L.; Peterson, J.E. Jr.

    1994-09-01

    This report summarizes the efforts of LBL to utilize MEQ data in reservoir definition as well as in evaluating its performance. Results of the study indicate that the velocity and attenuation variations correlate with the known geology of the field. At the NW Geysers, high velocity anomalies correspond to metagraywacke and greenstone units while low velocity anomalies seem to be associated with Franciscan melanges. Low Vp/Vs and high attenuation delineate the steam reservoir suggesting undersaturation of the reservoir rocks. Ongoing monitoring of Vp/Vs may be useful in tracking the expansion of the steam zone with time. Spatial and temporal patterns of seismicity exhibit compelling correlation with geothermal exploitation. Clusters of MEQs occur beneath active injection wells and appear to shift with changing injection activities. High resolution MEQ locations hold promise for inferring fluid flow paths, especially in tracking injectate. This study has demonstrated that continuous seismic monitoring may be useful as an active reservoir management tool.

  6. Geothermal energy resource assessment of parts of Alaska. Final report

    SciTech Connect

    Wescott, E.M.; Turner, D.L.; Kienle, J.

    1982-08-01

    The central Seward Peninsula was the subject of a geological, geophysical and geochemical reconnaissance survey during a 30-day period in the summer of 1980. The survey was designed to investigate the geothermal energy resource potential of this region of Alaska. A continental rift system model was proposed to explain many of the Late Tertiary-to-Quaternary topographic, structural, volcanic and geothermal features of the region. Geologic evidence for the model includes normal faults, extensive fields of young alkalic basalts, alignment of volcanic vents, graben valleys and other features consistent with a rift system active from late Miocene time to the present. Five traverses crossing segments of the proposed rift system were run to look for evidence of structure and geothermal resources not evident from surface manifestation. Gravity, helium and mercury soil concentrations were measured along the traverses. Seismic, resistivity, and VLF studies are presented.

  7. 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.

  8. Fracture Characterization in the Astor Pass Geothermal Field, Nevada

    NASA Astrophysics Data System (ADS)

    Walsh, D. C.; Reeves, D. M.; Pohll, G.; Lyles, B. F.; Cooper, C. A.

    2011-12-01

    The Astor Pass geothermal field, near Pyramid Lake, NV, is under study as a site of potential geothermal energy production. Three wells have been completed in the graben of this typical Basin and Range geologic setting. Lithologies include a layer of unconsolidated sediment (basin fill) underlain by various tertiary volcanic units and granodiorite and metavolcanic basement rock. Characterization of fractures within the relatively impermeable rock matrix is being conducted for the three wells. Statistical analysis of fracture orientation, densities, and spacing obtained from borehole imaging logs is used to determine stress orientation and to generate a statistically equivalent Discrete Fracture Network (DFN) model. Fractures at depth are compared to fracture data collected in nearby outcrops of the same lithologic stratigraphy. Fracture geometry and density is correlated to mechanically discrete layers within the stratigraphy to test whether variations in fracturing can be attributed to variations in Young's modulus. Correlation of fracture geometry and densities with spinner flowmeter logs and distributed temperature sensor records are made in an effort to identify potential flowing fracture zones intersecting the borehole. Mean fracture aperture is obtained from open fracture counts and reservoir-scale transmissivity values (computed from a 30 day pump test) in the absence of readily available aperture data. The goal of this thorough fracture characterization is to create a physically relevant model which may be coupled with a multipurpose fluid flow and thermal simulator for investigation of geothermal reservoir behavior, particularly at the borehole scale.

  9. Advanced materials for geothermal energy processes

    SciTech Connect

    Kukacka, L.E.

    1985-08-01

    The primary goal of the geothermal materials program is to ensure that the private sector development of geothermal energy resources is not constrained by the availability of technologically and economically viable materials of construction. This requires the performance of long-term high risk GHTD-sponsored materials R and D. Ongoing programs described include high temperature elastomers for dynamic sealing applications, advanced materials for lost circulation control, waste utilization and disposal, corrosion resistant elastomeric liners for well casing, and non-metallic heat exchangers. 9 refs.

  10. 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)

  11. 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.

  12. 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.

  13. Development of an Enhanced Two-Phase Production System at the Geysers Geothermal Field

    SciTech Connect

    Steven Enedy

    2001-12-14

    A method was developed to enhance geothermal steam production from two-phase wells at THE Geysers Geothermal Field. The beneficial result was increased geothermal production that was easily and economically delivered to the power plant.

  14. The Ahuachapan geothermal field, El Salvador: Reservoir analysis

    SciTech Connect

    Aunzo, Z.; Bodvarsson, G.S.; Laky, C.; Lippmann, M.J.; Steingrimsson, B.; Truesdell, A.H.; Witherspoon, P.A.; Icelandic National Energy Authority, Reykjavik; Geological Survey, Menlo Park, CA )

    1989-08-01

    These are appendices A thru E of the Ahuachapan geothermal field reservoir analysis. The volume contains: mineralogy contours, ionic chlorine and silicon dioxide contours, well summaries, and temperature and pressure effects. (JEF)

  15. Improved energy recovery from geothermal reservoirs

    SciTech Connect

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

    1982-09-01

    Numerical simulation methods are used to study how the exploitation of different horizons affects the behavior of a liquid-dominated geothermal reservoir. Our reservoir model is a schematic representation of the Olkaria field in Kenya. The model consists of a two-phase vapordominated zone overlying the main liquid-dominated reservoir. Four different cases were studied, with fluid produced from: (1) the vapor zone only, (2) the liquid zone only, (3) both zones, and (4) both zones but with lower values for vertical permeability and porosity assumed. The results indicate that production from the shallow two-phase zone, although resulting in higher enthalpy fluids, may not be advantageous in the long run. Shallow production gives rise to a rather localized depletion of the reservoir, whereas production from deeper horizons may yield a more uniform depletion process if vertical permeability is sufficiently large. The exploitation from deeper zones causes boiling and subsequent upflow of steam that condenses at shallow depths. This tends to make temperatures and pressures more uniform throughout the reservoir, resulting in maximum energy recovery.

  16. 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

  17. Three dimensional conductivity model of the Tendaho High Enthalpy Geothermal Field, NE Ethiopia

    NASA Astrophysics Data System (ADS)

    Didana, Y. L.; Thiel, S.; Heinson, G.

    2015-01-01

    Tendaho is one of the high enthalpy geothermal fields at advanced stage of exploration which is located in the Afar Depression in north eastern Ethiopia. Six deep and shallow geothermal wells were drilled in the field between 1993 and 1998. Here we present the first 3D conductivity model of the Tendaho high enthalpy geothermal field obtained from 3D inversion of magnetotelluric (MT) data. MT data from 116 sites at 24 selected periods in the period range from 0.003 s to 1000 s were used for the 3D inversion. The 3D conductivity model reveals three main resistivity structures to a depth of 20 km. The surface conductive structure (≤ 10 Ωm and > 1 km thick) is interpreted as sediments, geothermal fluids or hydrothermally altered clay cap. The underlying high resistivity structure in the Afar Stratiod basalts is associated with the deep geothermal reservoir. At a depth > 5 km, a high conductivity is observed across the whole of the Tendaho geothermal field. This structure is inferred to be the partial melt (heat source) of the geothermal system. The most striking feature in the 3D model is a fracture zone (upflow zone) in the Afar Stratoid basalts at the Dubti area, which acts as a pathway for geothermal fluids. Targeting the inferred fracture zone by directional drilling will likely increase the permeability and temperature of the deep reservoir in the basalts. Hence, the inferred presence of a fracture zone and shallow magma reservoir suggest that there is a huge potential (with temperature exceeding 270 °C at 2 km depth) at Tendaho for conventional hydrothermal geothermal energy development.

  18. A study of geothermal drilling and the production of electricity from geothermal energy

    SciTech Connect

    Pierce, K.G.; Livesay, B.J.

    1994-01-01

    This report gives the results of a study of the production of electricity from geothermal energy with particular emphasis on the drilling of geothermal wells. A brief history of the industry, including the influence of the Public Utilities Regulatory Policies Act, is given. Demand and supply of electricity in the United States are touched briefly. The results of a number of recent analytical studies of the cost of producing electricity are discussed, as are comparisons of recent power purchase agreements in the state of Nevada. Both the costs of producing electricity from geothermal energy and the costs of drilling geothermal wells are analyzed. The major factors resulting in increased cost of geothermal drilling, when compared to oil and gas drilling, are discussed. A summary of a series of interviews with individuals representing many aspects of the production of electricity from geothermal energy is given in the appendices. Finally, the implications of these studies are given, conclusions are presented, and program recommendations are made.

  19. Southwest Alaska Regional Geothermal Energy Projec

    SciTech Connect

    Holdmann, Gwen

    2015-04-30

    Drilling and temperature logging campaigns between the late 1970's and early 1980’s measured temperatures at Pilgrim Hot Springs in excess of 90°C. Between 2010 and 2014 the University of Alaska used a variety of methods including geophysical surveys, remote sensing techniques, heat budget modeling, and additional drilling to better understand the resource and estimate the available geothermal energy.

  20. Water Efficient Energy Production for Geothermal Resources

    SciTech Connect

    GTO

    2015-06-01

    Water consumption in geothermal energy development occurs at several stages along the life cycle of the plant, during construction of the wells, piping, and plant; during hydroshearing and testing of the reservoir (for EGS); and during operation of the plant. These stages are highlighted in the illustration above. For more information about actual water use during these stages, please see the back of this sheet..

  1. Enthalpy restoration in geothermal energy processing system

    DOEpatents

    Matthews, Hugh B.

    1983-01-01

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

  2. Modelling of Bouillante geothermal field (Guadeloupe, French West Indies)

    NASA Astrophysics Data System (ADS)

    Lakhssassi, Morad; Lopez, Simon; Calcagno, Philippe; Bouchot, Vincent

    2010-05-01

    The French islands of West Indies are experiencing rapid population growth. There is a consequent rise in energy demand with a high dependence on oil. In this context, and given their volcanic origin, the development of geothermal high energy in these islands is economically and environmentally interesting. Since the commissioning of the second production unit of the plant of Bouillante in 2005, geothermal energy provides 6 to 8% of electricity consumption energy of the Guadeloupe island. Yet, the geothermal fluid withdrawal was tripled which induced an increase in the quantity of separated brines which are cooled and mixed with sea water before disposal to the sea. It also caused a change in the Bouillante reservoir behavior and well head pressures evolution with a quick and steady pressure drop. Consequently, to optimize the exploitation of the geothermal resource, there was need to better characterize the reservoir, predict pressures evolution and plan reinjection of the separated brines. With this aim in view, available data were gathered to build a geological model integrating both regional and reservoir scale data. In parallel, a 3D hydrodynamic model using the computer code TOUGH 2 is developed to study and predict the behavior of pressure and temperature of Bouillante geothermal field during its exploitation and evaluate the contribution of reinjection to exploitation strategy. Both models should ultimately be linked. The hydrodynamic model is centered on neighboring wells BO-4, BO-5 and BO-6 which are the three producing wells at the moment. The old producing well BO-2 is now used to monitor pressure evolutions at the top of the reservoir. As a first step, model parameters were fitted to reproduce the pressure interference between the three wells recorded between July 2002 and April 2003 when well BO-5 was the only producing well. The model reproduces the hydrodynamic properties of the reservoir via the MINC method (Multiple INteracting Continua). (Pruess

  3. Origin of first cells at terrestrial, anoxic geothermal fields.

    PubMed

    Mulkidjanian, Armen Y; Bychkov, Andrew Yu; Dibrova, Daria V; Galperin, Michael Y; Koonin, Eugene V

    2012-04-01

    All cells contain much more potassium, phosphate, and transition metals than modern (or reconstructed primeval) oceans, lakes, or rivers. Cells maintain ion gradients by using sophisticated, energy-dependent membrane enzymes (membrane pumps) that are embedded in elaborate ion-tight membranes. The first cells could possess neither ion-tight membranes nor membrane pumps, so the concentrations of small inorganic molecules and ions within protocells and in their environment would equilibrate. Hence, the ion composition of modern cells might reflect the inorganic ion composition of the habitats of protocells. We attempted to reconstruct the "hatcheries" of the first cells by combining geochemical analysis with phylogenomic scrutiny of the inorganic ion requirements of universal components of modern cells. These ubiquitous, and by inference primordial, proteins and functional systems show affinity to and functional requirement for K(+), Zn(2+), Mn(2+), and phosphate. Thus, protocells must have evolved in habitats with a high K(+)/Na(+) ratio and relatively high concentrations of Zn, Mn, and phosphorous compounds. Geochemical reconstruction shows that the ionic composition conducive to the origin of cells could not have existed in marine settings but is compatible with emissions of vapor-dominated zones of inland geothermal systems. Under the anoxic, CO(2)-dominated primordial atmosphere, the chemistry of basins at geothermal fields would resemble the internal milieu of modern cells. The precellular stages of evolution might have transpired in shallow ponds of condensed and cooled geothermal vapor that were lined with porous silicate minerals mixed with metal sulfides and enriched in K(+), Zn(2+), and phosphorous compounds.

  4. Shear velocity of the Rotokawa geothermal field using ambient noise

    NASA Astrophysics Data System (ADS)

    Civilini, F.; Savage, M. K.; Townend, J.

    2014-12-01

    Ambient noise correlation is an increasingly popular seismological technique that uses the ambient seismic noise recorded at two stations to construct an empirical Green's function. Applications of this technique include determining shear velocity structure and attenuation. An advantage of ambient noise is that it does not rely on external sources of seismic energy such as local or teleseismic earthquakes. This method has been used in the geothermal industry to determine the depths at which magmatic processes occur, to distinguish between production and non-production areas, and to observe seismic velocity perturbations associated with fluid extraction. We will present a velocity model for the Rotokawa geothermal field near Taupo, New Zealand, produced from ambient noise cross correlations. Production at Rotokawa is based on the "Rotokawa A" combined cycle power station established in 1997 and the "Nga Awa Purua" triple flash power plant established in 2010. Rotokawa Joint Venture, a partnership between Mighty River Power and Tauhara North No. 2 Trust currently operates 174 MW of generation at Rotokawa. An array of short period seismometers was installed in 2008 and occupies an area of roughly 5 square kilometers around the site. Although both cultural and natural noise sources are recorded at the stations, the instrument separation distance provides a unique challenge for analyzing cross correlations produced by both signal types. The inter-station spacing is on the order of a few kilometers, so waves from cultural sources generally are not coherent from one station to the other, while the wavelength produced by natural noise is greater than the station separation. Velocity models produced from these two source types will be compared to known geological models of the site. Depending on the amount of data needed to adequately construct cross-correlations, a time-dependent model of velocity will be established and compared with geothermal production processes.

  5. Origin of first cells at terrestrial, anoxic geothermal fields.

    PubMed

    Mulkidjanian, Armen Y; Bychkov, Andrew Yu; Dibrova, Daria V; Galperin, Michael Y; Koonin, Eugene V

    2012-04-01

    All cells contain much more potassium, phosphate, and transition metals than modern (or reconstructed primeval) oceans, lakes, or rivers. Cells maintain ion gradients by using sophisticated, energy-dependent membrane enzymes (membrane pumps) that are embedded in elaborate ion-tight membranes. The first cells could possess neither ion-tight membranes nor membrane pumps, so the concentrations of small inorganic molecules and ions within protocells and in their environment would equilibrate. Hence, the ion composition of modern cells might reflect the inorganic ion composition of the habitats of protocells. We attempted to reconstruct the "hatcheries" of the first cells by combining geochemical analysis with phylogenomic scrutiny of the inorganic ion requirements of universal components of modern cells. These ubiquitous, and by inference primordial, proteins and functional systems show affinity to and functional requirement for K(+), Zn(2+), Mn(2+), and phosphate. Thus, protocells must have evolved in habitats with a high K(+)/Na(+) ratio and relatively high concentrations of Zn, Mn, and phosphorous compounds. Geochemical reconstruction shows that the ionic composition conducive to the origin of cells could not have existed in marine settings but is compatible with emissions of vapor-dominated zones of inland geothermal systems. Under the anoxic, CO(2)-dominated primordial atmosphere, the chemistry of basins at geothermal fields would resemble the internal milieu of modern cells. The precellular stages of evolution might have transpired in shallow ponds of condensed and cooled geothermal vapor that were lined with porous silicate minerals mixed with metal sulfides and enriched in K(+), Zn(2+), and phosphorous compounds. PMID:22331915

  6. Evaluation of geothermal energy in Arizona. Quarterly progress report, July 1-September 30, 1981

    SciTech Connect

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

    1981-01-01

    Progress is reported on the following: legislative and institutional program, cities program, geothermal applications utilization technology, integrated alcohol/feedlot/geothermal operation, geothermal energy in the mining industry, geothermal space heating and cooling, identification of a suitable industry for a remote geothermal site, irrigation pumping, coal-fired/geothermal-assisted power plants, area development plans, and outreach. (MHR)

  7. The Impact of Injection on Seismicity at The Geyses, CaliforniaGeothermal Field

    SciTech Connect

    Majer, Ernest L.; Peterson, John E.

    2006-09-25

    Water injection into geothermal systems has often become arequired strategy to extended and sustain production of geothermalresources. To reduce a trend of declining pressures and increasingnon-condensable gas concentrations in steam produced from The Geysers,operators have been injecting steam condensate, local rain and streamwaters, and most recently treated wastewater piped to the field fromneighboring communities. If geothermal energy is to provide a significantincrease in energy in the United States (US Department of Energy (DOE)goal is 40,000 megawatts by 2040), injection must play a larger role inthe overall strategy, i.e., enhanced geothermal systems, (EGS). Presentedin this paper are the results of monitoring microseismicity during anincrease in injection at The Geysers field in California using data froma high-density digital microearthquake array. Although seismicity hasincreased due to increased injection it has been found to be somewhatpredicable, thus implying that intelligent injection control may be ableto control large increases in seismicity.

  8. Geothermal Energy Production from Oil/Gas Wells and Application for Building Cooling

    SciTech Connect

    Wang, Honggang; Liu, Xiaobing

    2016-01-01

    One significant source of low-temperature geothermal energy is the coproduced hot water from oil/gas field production. In the United States, daily oil production has reached above 8 million barrels in recent years. Considering various conditions of wells, 5-10 times or more water can be coproduced in the range of temperature 120 F to 300 F. Like other geothermal resources, such energy source from oil/gas wells is under-utilized for its typical long distance from consumption sites. Many oil/gas fields, however, are relatively close (less than 10 miles) to consumers around cities. For instance, some petroleum fields in Pennsylvania are only a few miles away from the towns in Pittsburg area and some fields in Texas are quite close to Houston. In this paper, we evaluate geothermal potential from oil/gas wells by conducting numerical simulation and analysis of a fractured oil well in Hastings West field, Texas. The results suggest that hot water can be continuously coproduced from oil wells at a sufficient rate (about 4000 gallons/day from one well) for more than 100 years. Viable use of such geothermal source requires economical transportation of energy to consumers. The recently proposed two-step geothermal absorption (TSGA) system provides a promising energy transport technology that allows large-scale use of geothermal energy from thousands of oil/gas wells.

  9. Exploration and development of the Cerro Prieto geothermal field

    SciTech Connect

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

    1983-07-01

    A multidisciplinary effort to locate, delineate, and characterize the geothermal system at Cerro Prieto, Baja California, Mexico, began about 25 years ago. It led to the identification of an important high-temperature, liquid-dominated geothermal system which went into production in 1973. Initially, the effort was undertaken principally by the Mexican electric power agency, the Comision Federal de Electricidad (CFE). Starting in 1977 a group of US organizations sponsored by the US Department of Energy, joined CFE in this endeavor. An evaluation of the different studies carried out at Cerro Prieto has shown that: (1) surface electrical resistivity and seismic reflection surveys are useful in defining targets for exploratory drilling; (2) the mineralogical studies of cores and cuttings and the analysis of well logs are important in designing the completion of wells, identifying geological controls on fluid movement, determining thermal effects and inferring the thermal history of the field; (3) geochemical surveys help to define zones of recharge and paths of fluid migration; and (4) reservoir engineering studies are necessary in establishing the characteristics of the reservoir and in predicting its response to fluid production.

  10. Geothermal energy potential in the San Luis Valley, Colorado

    SciTech Connect

    Coe, B.A.

    1980-01-01

    The background of the area itself is investigated considering the geography, population, economy, attitudes of residents, and energy demands of the area. The requirements for geothermal energy development are considered, including socio-economic, institutional, and environmental conditions as well as some technical aspects. The current, proposed, and potential geothermal energy developments are described. The summary, conclusions, and methodology are included. (MHR)

  11. Geothermal well-field and power-plant investment-decision analysis

    SciTech Connect

    Cassel, T.A.V.; Amundsen, C.B.; Edelstein, R.H.; Blair, P.D.

    1981-05-31

    Investment decisions pertaining to hydrothermal well fields and electric power plants are analyzed. Geothermal investment decision models were developed which, when coupled to a site-specific stochastic cash flow model, estimate the conditional probability of a positive decision to invest in the development of geothermal resource areas. Quantitative decision models have been developed for each major category of investor currently involved in the hydrothermal projects. These categories include: large, diversified energy resource corporations; independently operating resource firms; investor-owned electric utilities; municipal electric utilities; state-run resource agencies; and private third-party power plant investors. The geothermal cash flow, the investment decision analysis, and an example of model application for assessing the likely development of geothermal resource areas are described. The sensitivity of this investment behavior to federal incentives and research goals is also analyzed and discussed.

  12. Energy analysis of four geothermal technologies

    NASA Astrophysics Data System (ADS)

    Herendeen, R. A.; Plant, R. L.

    1981-01-01

    Standard energy analysis was applied to liquid-dominated, hot dry rock, geopressure, and vapor-dominated geothermal-electric technologies. It was shown that the four processes are net energy producers, so that the ratios of net electric energy produced over lifetime to primary nonrenewable energy inputs over lifetime exceed unity. The highest energy ratio of 13 + or - 4 is characteristic of vapor-dominated (dry-stream) technology, which is the only method used commercially to produce electricity in the U.S. It is concluded that the energy ratios computed are similar to those of other authors; however, the estimates for liquid-dominated systems are significantly lower due to the inclusion of environmental control costs.

  13. Assessing geothermal energy potential in upstate New York. Final report

    SciTech Connect

    Hodge, D.S.

    1996-08-01

    The potential of geothermal energy for future electric power generation in New York State is evaluated using estimates of temperatures of geothermal reservoir rocks. Bottom hole temperatures from over 2000 oil and gas wells in the region were integrated into subsurface maps of the temperatures for specific geothermal reservoirs. The Theresa/Potsdam formation provides the best potential for extraction of high volumes of geothermal fluids. The evaluation of the Theresa/Potsdam geothermal reservoir in upstate New York suggests that an area 30 miles east of Elmira, New York has the highest temperatures in the reservoir rock. The Theresa/Potsdam reservoir rock should have temperatures about 136 {degrees}C and may have as much as 450 feet of porosity in excess of 8%. Estimates of the volumes of geothermal fluids that can be extracted are provided and environmental considerations for production from a geothermal well is discussed.

  14. Engineered Geothermal Systems Energy Return On Energy Investment

    SciTech Connect

    Mansure, A J

    2012-12-10

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

  15. An overview of the Department of Energy Geothermal Program

    SciTech Connect

    Mock, John E.

    1988-01-01

    Overview of current emphases of the U. S. Department of Energy's Geothermal Technology R&D program in reservoir technology, hard rock penetration, conversion technology, geopressured research, hot dry rock research, magma energy research; invitation to audience to participate in DoE Geothermal Program Review VI.

  16. The possibilities of utilisation of heat from Tattapani Geothermal field, India

    SciTech Connect

    Sarolkar, P.B.; Pitale, U.L.

    1996-12-31

    The Tattapani Geothermal field produces + 1800 1pm thermal water of 100{degrees}C from five production wells. The hot water production can sustain electricity production of 300 kWe by using a binary cycle power plant. The heat energy of effluent water from power plant can be utilized for direct heat utilization on horticulture, aquaculture, cold storage, silviculture etc; to augment the economics of the power plant be spot can be developed as a centre for tourist attraction by constructing botanical park, greenhouse, geyser show and crocodile farm. The direct heat utilization shemes can be planned in cascading order to achieve maximum utility of thermal water. Additional deep drilling is essential for optimum commercial utilization of the Geothermal energy. The direct heat utilisation shemes along with binary cycle power plant may help in development of the geothermal energy and boosting the economy of this region.

  17. The flow path of geothermal fluid and water-rock interaction in the geothermal field, Taiwan

    NASA Astrophysics Data System (ADS)

    Liu, C.; Kuo, C.; Tsai, Y.; Song, S.

    2013-12-01

    The flow path of geothermal fluid and water-rock interaction of hydrothermal area has been proved as a useful tool for calculating the temperature of geothermal reservoir. Taiwan is located at the Ring of Fire with many great geothermal potential areas. The Chingshui and Kuantzuling are two selected geothermal systems with different surrounding rocks,, the metamorphic and sedimentary rock, respectively for the study . The Chingshui geothermal field is located in the slate formation of the Central Range with in-situ temperature and pH values of hot springs ranging from 63.2 °C to 96.0 °C and 6.14 to 9.2, respectively. According to the concentrations of major elements, this hot spring can be characterized as the Na-HCO3- water type. The oxygen and hydrogen isotopic ratio of these samples are from -6.56 ‰ to -4.66 ‰ and from -54.1 ‰ to -40.3 ‰, respectively. The sulfur isotopic values are between -4.75 ‰ and 2.89 ‰. On the other hand, The Kuantzuling hot spring is located in the Pliocene formation of sedimentary terrain of the Western Foothills with the oxygen and hydrogen isotopic ratio ranging from -5.07 ‰ to 5.37 ‰ and from -43.1 ‰ to -18.2 ‰, respectively This hydrothermal water is classified as Na-HCO3--Cl- type water. Different geothermometries will be applied associated with analyzing mineral assemblage of hydrothermal area to construct the flow path of geothermal fluid and water-rock interaction and calculate the temperature values of geothermal reservoir in the future.

  18. Utilization of geothermal energy in the mining and processing of tungsten ore. Final report

    SciTech Connect

    Erickson, M.V.; Lacy, S.B.; Lowe, G.D.; Nussbaum, A.M.; Walter, K.M.; Willens, C.A.

    1981-01-01

    The engineering, economic, and environmental feasibility of the use of low and moderate temperature geothermal heat in the mining and processing of tungsten ore is explored. The following are covered: general engineering evaluation, design of a geothermal energy system, economics, the geothermal resource, the institutional barriers assessment, environmental factors, an alternate geothermal energy source, and alternates to geothermal development. (MHR)

  19. Economics and applications of geothermal energy in St. Lucia

    SciTech Connect

    Altseimer, J.H.; Burris, A.E.; Edeskuty, F.J.; Trocki, L.K.; Williamson, K.D. Jr.

    1984-01-01

    The assessment reported here consisted of three major tasks: first, a field geologic assessment of the physical extent of the Qualibou caldera geothermal resource; second, an engineering evaluation of the potential development of the geothermal resource; and third, a study of the potential economic impact upon St. Lucia associated with the development of the geothermal resource. The first task, the geologic assessment, is not discussed in detail.

  20. GEOTHERMAL / SOLAR HYBRID DESIGNS: USE OF GEOTHERMAL ENERGY FOR CSP FEEDWATER HEATING

    SciTech Connect

    Craig Turchi; Guangdong Zhu; Michael Wagner; Tom Williams; Dan Wendt

    2014-10-01

    This paper examines a hybrid geothermal / solar thermal plant design that uses geothermal energy to provide feedwater heating in a conventional steam-Rankine power cycle deployed by a concentrating solar power (CSP) plant. The geothermal energy represents slightly over 10% of the total thermal input to the hybrid plant. The geothermal energy allows power output from the hybrid plant to increase by about 8% relative to a stand-alone CSP plant with the same solar-thermal input. Geothermal energy is converted to electricity at an efficiency of 1.7 to 2.5 times greater than would occur in a stand-alone, binary-cycle geothermal plant using the same geothermal resource. While the design exhibits a clear advantage during hybrid plant operation, the annual advantage of the hybrid versus two stand-alone power plants depends on the total annual operating hours of the hybrid plant. The annual results in this draft paper are preliminary, and further results are expected prior to submission of a final paper.

  1. Geothermal energy: a proven resource with costly potential

    SciTech Connect

    Not Available

    1980-08-01

    The commercial use of geothermal energy to generate electricity has been spreading across the country since the California Geyser site was developed in 1960. Petroleum companies see geothermal power generation as a way to broaden their own base. The binary-cycle technology to use hydrothermal resources will be ready by 1985. Power generation from geothermal heat will be costly even though the resource itself is free and renewable; but the economics will improve as fossil-fuel prices increase. (DCK)

  2. Geothermal energy control system and method

    DOEpatents

    Matthews, Hugh B.

    1977-01-01

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

  3. 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.

  4. 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.

  5. Anthropogenic seismicity rates and operational parameters at the Salton Sea Geothermal Field.

    PubMed

    Brodsky, Emily E; Lajoie, Lia J

    2013-08-01

    Geothermal power is a growing energy source; however, efforts to increase production are tempered by concern over induced earthquakes. Although increased seismicity commonly accompanies geothermal production, induced earthquake rate cannot currently be forecast on the basis of fluid injection volumes or any other operational parameters. We show that at the Salton Sea Geothermal Field, the total volume of fluid extracted or injected tracks the long-term evolution of seismicity. After correcting for the aftershock rate, the net fluid volume (extracted-injected) provides the best correlation with seismicity in recent years. We model the background earthquake rate with a linear combination of injection and net production rates that allows us to track the secular development of the field as the number of earthquakes per fluid volume injected decreases over time.

  6. Anthropogenic seismicity rates and operational parameters at the Salton Sea Geothermal Field.

    PubMed

    Brodsky, Emily E; Lajoie, Lia J

    2013-08-01

    Geothermal power is a growing energy source; however, efforts to increase production are tempered by concern over induced earthquakes. Although increased seismicity commonly accompanies geothermal production, induced earthquake rate cannot currently be forecast on the basis of fluid injection volumes or any other operational parameters. We show that at the Salton Sea Geothermal Field, the total volume of fluid extracted or injected tracks the long-term evolution of seismicity. After correcting for the aftershock rate, the net fluid volume (extracted-injected) provides the best correlation with seismicity in recent years. We model the background earthquake rate with a linear combination of injection and net production rates that allows us to track the secular development of the field as the number of earthquakes per fluid volume injected decreases over time. PMID:23845943

  7. Solar and Geothermal Energy: New Competition for the Atom

    ERIC Educational Resources Information Center

    Carter, Luther J.

    1974-01-01

    Describes new emphasis on research into solar and geothermal energy resources by governmental action and recent legislation and the decreased emphasis on atomic power in supplementing current energy shortages. (BR)

  8. Natural State Model of the Nesjavellir Geothermal Field, Iceland

    SciTech Connect

    Bodvarsson, G.S.; Pruess, K.; Stefansson, V.; Steingrimsson, B.; Bjornsson, S.; Gunnarsson, A.; Gunnlaugsson, E.

    1986-01-21

    The Nesjavellir geothermal system in southern Iceland is very complex from both a thermal and hydrologic point of view. There are large pressure and temperature gradients in the wellfield and zones with drastically different pressure potentials. Thus, natural fluid flow is substantial in the system and flow patterns are complex. We have developed a two-dimensional natural state model for the Nesjavellir system that matches reasonably well the observed pressure and temperature distributions. The match with field data has allowed determination of the energy recharge to the system and the permeability distribution. Fluids recharge the system at rate of 0.02 kg/s/m with an enthalpy of 1460 kJ/kg. The permeability in the main reservoir is estimated to be in the range of 1.5 to 2.0 md, which agrees well with injection test results from individual wells. Permeabilities in shallower reservoirs are about an order of magnitude higher. Most of the main reservoir is under twephase conditions, as are shallow aquifers in the southern part of the field. The model results also suggest that the low temperatures in the shallow part of the northern region of the field may be due to the young age of the system; i.e., the system is gradually heating up. If this is the case the estimated age of the system near the wellfield is on the order of a few thousand years.

  9. Geothermal energy control system and method

    DOEpatents

    Matthews, Hugh B.

    1976-01-01

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

  10. A guide to geothermal energy and the environment

    SciTech Connect

    Kagel, Alyssa; Bates, Diana; Gawell, Karl

    2005-04-22

    Geothermal energy, defined as heat from the Earth, is a statute-recognized renewable resource. The first U.S. geothermal power plant, opened at The Geysers in California in 1960, continues to operate successfully. The United States, as the world's largest producer of geothermal electricity, generates an average of 15 billion kilowatt hours of power per year, comparable to burning close to 25 million barrels of oil or 6 million short tons of coal per year. Geothermal has a higher capacity factor (a measure of the amount of real time during which a facility is used) than many other power sources. Unlike wind and solar resources, which are more dependent upon weather fluctuations and climate changes, geothermal resources are available 24 hours a day, 7 days a week. While the carrier medium for geothermal electricity (water) must be properly managed, the source of geothermal energy, the Earth's heat, will be available indefinitely. A geothermal resource assessment shows that nine western states together have the potential to provide over 20 percent of national electricity needs. Although geothermal power plants, concentrated in the West, provide the third largest domestic source of renewable electricity after hydropower and biomass, they currently produce less than one percent of total U.S. electricity.

  11. A Resource Assessment Of Geothermal Energy Resources For Converting Deep Gas Wells In Carbonate Strata Into Geothermal Extraction Wells: A Permian Basin Evaluation

    SciTech Connect

    Erdlac, Richard J., Jr.

    2006-10-12

    Previously conducted preliminary investigations within the deep Delaware and Val Verde sub-basins of the Permian Basin complex documented bottom hole temperatures from oil and gas wells that reach the 120-180C temperature range, and occasionally beyond. With large abundances of subsurface brine water, and known porosity and permeability, the deep carbonate strata of the region possess a good potential for future geothermal power development. This work was designed as a 3-year project to investigate a new, undeveloped geographic region for establishing geothermal energy production focused on electric power generation. Identifying optimum geologic and geographic sites for converting depleted deep gas wells and fields within a carbonate environment into geothermal energy extraction wells was part of the project goals. The importance of this work was to affect the three factors limiting the expansion of geothermal development: distribution, field size and accompanying resource availability, and cost. Historically, power production from geothermal energy has been relegated to shallow heat plumes near active volcanic or geyser activity, or in areas where volcanic rocks still retain heat from their formation. Thus geothermal development is spatially variable and site specific. Additionally, existing geothermal fields are only a few 10’s of square km in size, controlled by the extent of the heat plume and the availability of water for heat movement. This plume radiates heat both vertically as well as laterally into the enclosing country rock. Heat withdrawal at too rapid a rate eventually results in a decrease in electrical power generation as the thermal energy is “mined”. The depletion rate of subsurface heat directly controls the lifetime of geothermal energy production. Finally, the cost of developing deep (greater than 4 km) reservoirs of geothermal energy is perceived as being too costly to justify corporate investment. Thus further development opportunities

  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 Field Near Rotorua, New Zealand

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Historical sketches show the indigenous Maori cooking with natural hot waters and steam prior to the arrival of Europeans on North Island, New Zealand. Since the 1950s, geothermal heat and steam have been exploited for both heating and electrical power generation, and some excess electrical power is exported to South Island. The geothermal development can be identified by the unique patterns of infrastructure that look like tan beads on a string in the midst of otherwise green vegetation. This one near the town of Rotorua lies within a northeast-trending line of active volcanoes (Ruapehu, Tongariro, and White Island) that are the surface result of the Pacific tectonic plate descending beneath the Australian-Indian plate. Image STS110-726-10 was taken by space shuttle crewmembers in April 2002 using a Hasselblad film camera. Image provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography of Earth.

  14. Sustainability assessment of geothermal exploitation by numerical modelling: the example of high temperature Mofete geothermal field at Campi Flegrei caldera (Southern Italy)

    NASA Astrophysics Data System (ADS)

    Carlino, Stefano; Troiano, Antonio; Giulia Di Giuseppe, Maria; Tramelli, Anna; Troise, Claudia; Somma, Renato; De Natale, Giuseppe

    2015-04-01

    The active volcanic area of Campi Flegrei caldera has been the site of many geothermal investigations, since the early XX century. This caldera is characterised by high heat flow, with maximum value > 150 mWm-2, geothermal gradients larger than 200°Ckm-1 and diffuse magmatic gases discharge at the surface. These features encouraged an extensive campaign for geothermal investigation, started in 1939, with many drillings performed at Campanian volcanoes (Campi Flegrei and Ischia) and later at Vesuvius. Several wells aimed to the exploitation of high enthalpy geothermal energy, were drilled in the Campi Flegrei caldera, down to a maximum depth of ~3 km involving mainly two sites (Mofete and S.Vito geothermal fields) located in western and northern sector of caldera respectively. The most interesting site for geothermal exploitation was the Mofete zone, where a number of 4 productive wells were drilled and tested to produce electrical power. Based on data inferred from the productive tests it was established a potential electrical extractable power from Mofete field of at least 10MWe. More recently an empirical evaluation of the whole geothermal potential of the caldera provides a value of more than 1 GWe. The results of AGIP-ENEL exploration at Campi Flegrei highlighted the feasibility of geothermal exploitation. Here, we show for the first time the results of numerical simulations (TOUGH2 code ®) of fluids extraction and reinjection from the Mofete geothermal field, in order to produce at least 5MWe from zero emission power plant (Organic Rankine Cycle type). The simulation is aimed to understand the perturbation of the geothermal reservoir in terms of temperature, pressure change, and possible related seismicity, after different simulated time of exploitation. The modeling is mainly constrained by the data derived from geothermal exploration and productive tests performed since 1979 by AGIP-ENEL Companies. A general assessment of the maximum potential magnitude

  15. Interactive Maps from the Great Basin Center for Geothermal Energy

    DOE Data Explorer

    The Great Basin Center for Geothermal Energy, part of the University of Nevada, Reno, conducts research towards the establishment of geothermal energy as an economically viable energy source within the Great Basin. The Center specializes in collecting and synthesizing geologic, geochemical, geodetic, geophysical, and tectonic data, and using Geographic Information System (GIS) technology to view and analyze this data and to produce favorability maps of geothermal potential. The interactive maps are built with layers of spatial data that are also available as direct file downloads (see DDE00299). The maps allow analysis of these many layers, with various data sets turned on or off, for determining potential areas that would be favorable for geothermal drilling or other activity. They provide information on current exploration projects and leases, Bureau of Land Management land status, and map presentation of each type of scientific spatial data: geothermal, geophysical, geologic, geodetic, groundwater, and geochemical.

  16. Industrial application of geothermal energy in Southeast Idaho

    SciTech Connect

    Batdorf, J.A.; McClain, D.W.; Gross, M.; Simmons, G.M.

    1980-02-01

    Those phosphate related and food processing industries in Southeastern Idaho are identified which require large energy inputs and the potential for direct application of geothermal energy is assessed. The total energy demand is given along with that fractional demand that can be satisfied by a geothermal source of known temperature. The potential for geothermal resource development is analyzed by examining the location of known thermal springs and wells, the location of state and federal geothermal exploration leases, and the location of federal and state oil and gas leasing activity in Southeast Idaho. Information is also presented regarding the location of geothermal, oil, and gas exploration wells in Southeast Idaho. The location of state and federal phosphate mining leases is also presented. This information is presented in table and map formats to show the proximity of exploration and development activities to current food and phosphate processing facilities and phosphate mining activities. (MHR)

  17. Velocity and Attenuation Structure of the Geysers Geothermal Field, California

    SciTech Connect

    Zucca, J. J.; Hutchings, L. J.; Kasameyer, P. W.

    1993-01-01

    The Geysers geothermal field is located in northern California and is one of the world's largest producers of electricity from geothermal energy. The resource consists of primarily dry steam which is produced from a low, porosity fractured graywacke. Over the last several years steam pressure at the Geysers has been dropping. Concern over decline of the resource has prompted research to understand its fundamental nature. A key issue is the distribution of fluid in the matrix of the reservoir rock. In this paper we interpret seismic compressional-wave velocity and attenuation data at the Geysers in terms of the geologic structure and fluid saturation in the reservoir. Our data consist of approximately 300 earthquakes that are of magnitude 1.2 and are distributed in depth between sea level and 2.5 km. Using compressional-wave arrival times, we invert for earthquake location, origin time, and velocity along a three-dimensional grid. Using the initial pulse width of the compressional-wave, we invert for the initial pulse width associated with the source, and the one-dimensional Q structure. We find that the velocity structure correlates with known mapped geologic units, including a velocity high that is correlated with a felsite body at depth that is known from drilling. The dry steam reservoir, which is also known from drilling, is mostly correlated with low velocity. The Q increases with depth to the top of the dry steam reservoir and decreases with depth within the reservoir. The decrease of Q with depth probably indicates that the saturation of the matrix of the reservoir rock increases with depth.

  18. Geothermal Program Review XIV: proceedings. Keeping Geothermal Energy Competitive in Foreign and Domestic Markets

    SciTech Connect

    1996-01-01

    The U.S. Department of Energy`s Office of Geothermal Technologies conducted its annual Program Review XIV in Berkeley, April 8-10, 1996. The geothermal community came together for an in-depth review of the federally-sponsored geothermal research and development program. This year`s theme focused on ``Keeping Geothermal Energy Competitive in Foreign and Domestic Markets.`` This annual conference is designed to promote technology transfer by bringing together DOE-sponsored researchers; utility representatives; geothermal developers; equipment and service suppliers; representatives from local, state, and federal agencies; and others with an interest in geothermal energy. Program Review XIV consisted of eight sessions chaired by industry representatives. Introductory and overview remarks were presented during every session followed by detailed reports on specific DOE-funded research projects. The progress of R&D projects over the past year and plans for future activities were discussed. The government-industry partnership continues to strengthen -- its success, achievements over the past twenty years, and its future direction were highlighted throughout the conference. The comments received from the conference evaluation forms are published in this year`s proceedings. Individual papers have been processed for inclusion in the Energy Science and Technology Database.

  19. Potential geothermal energy applications for Idaho Elks Rehabilitation Hospital

    SciTech Connect

    Austin, J.C.

    1981-11-01

    Several potential applications of geothermal energy for the Idaho Elks Rehabilitation Hospital are outlined. A brief background on the resource and distribution system, is provided; which hospital heating systems should be considered for potential geothermal retrofit is discussed; and technical and economic feasibility are addressed.

  20. Impact of enhanced geothermal systems on US energy supply in the twenty-first century.

    PubMed

    Tester, Jefferson W; Anderson, Brian J; Batchelor, Anthony S; Blackwell, David D; DiPippo, Ronald; Drake, Elisabeth M; Garnish, John; Livesay, Bill; Moore, Michal C; Nichols, Kenneth; Petty, Susan; Toksoz, M Nafi; Veatch, Ralph W; Baria, Roy; Augustine, Chad; Murphy, Enda; Negraru, Petru; Richards, Maria

    2007-04-15

    Recent national focus on the value of increasing US supplies of indigenous renewable energy underscores the need for re-evaluating all alternatives, particularly those that are large and well distributed nationally. A panel was assembled in September 2005 to evaluate the technical and economic feasibility of geothermal becoming a major supplier of primary energy for US base-load generation capacity by 2050. Primary energy produced from both conventional hydrothermal and enhanced (or engineered) geothermal systems (EGS) was considered on a national scale. This paper summarizes the work of the panel which appears in complete form in a 2006 MIT report, 'The future of geothermal energy' parts 1 and 2. In the analysis, a comprehensive national assessment of US geothermal resources, evaluation of drilling and reservoir technologies and economic modelling was carried out. The methodologies employed to estimate geologic heat flow for a range of geothermal resources were utilized to provide detailed quantitative projections of the EGS resource base for the USA. Thirty years of field testing worldwide was evaluated to identify the remaining technology needs with respect to drilling and completing wells, stimulating EGS reservoirs and converting geothermal heat to electricity in surface power and energy recovery systems. Economic modelling was used to develop long-term projections of EGS in the USA for supplying electricity and thermal energy. Sensitivities to capital costs for drilling, stimulation and power plant construction, and financial factors, learning curve estimates, and uncertainties and risks were considered.

  1. Evaluation of geothermal energy in Arizona. Quarterly topical progress report, July 1-September 30, 1981

    SciTech Connect

    White, D.H.

    1981-01-01

    Progress is reported on the following: the legislative and institutional program, cities program, outreach, the integrated alcohol/feedlot/geothermal operation, geothermal energy in the mining industry, geothermal space heating and cooling, identification of a suitable industry for a remote geothermal site, irrigation pumping, coal-fired/geothermal-assisted power plants, and area development plans. (MHR)

  2. 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.

  3. Structural Controls of the Tuscarora Geothermal Field, Elko County, Nevada

    NASA Astrophysics Data System (ADS)

    Dering, Gregory M.

    Detailed geologic mapping, structural analysis, and well data have been integrated to elucidate the stratigraphic framework and structural setting of the Tuscarora geothermal area. Tuscarora is an amagmatic geothermal system that lies in the northern part of the Basin and Range province, ˜15 km southeast of the Snake River Plain and ˜90 km northwest of Elko, Nevada. The Tuscarora area is dominated by late Eocene to middle Miocene volcanic and sedimentary rocks, all overlying Paleozoic metasedimentary rocks. A geothermal power plant was constructed in 2011 and currently produces 18 MWe from an ˜170°C reservoir in metasedimentary rocks at a depth of 1740 m. Analysis of drill core reveals that the subsurface geology is dominated to depths of ˜700-1000 m by intracaldera deposits of the Eocene Big Cottonwood Canyon caldera, including blocks of basement-derived megabreccia. Furthermore, the Tertiary-Paleozoic nonconformity within the geothermal field has been recognized as the margin of this Eocene caldera. Structural relations combined with geochronologic data from previous studies indicate that Tuscarora has undergone extension since the late Eocene, with significant extension in the late Miocene-Pliocene to early Pleistocene. Kinematic analysis of fault slip data reveal an east-west-trending least principal paleostress direction, which probably reflects an earlier episode of Miocene extension. Two distinct structural settings at different scales appear to control the geothermal field. The regional structural setting is a 10-km wide complexly faulted left step or relay ramp in the west-dipping range-bounding Independence-Bull Run Mountains normal fault system. Geothermal activity occurs within the step-over where sets of east- and west-dipping normal faults overlap in a northerly trending accommodation zone. The distribution of hot wells and hydrothermal surface features, including boiling springs, fumaroles, and siliceous sinter, indicate that the geothermal

  4. Improved energy recovery from geothermal reservoirs

    NASA Astrophysics Data System (ADS)

    Boedvarsson, G. S.; Pruess, K.; Lippmann, M.; Bjoernsson, S.

    1981-06-01

    Numerical simulation methods are used to study how the exploitation of different horizons affects the behavior of a liquid-dominated geothermal reservoir. The reservoir model is a schematic representation of the Olkaria field in Kenya. The model consists of a two phase vapor dominated zone overlying the main liquid dominated reservoir. Four different cases were studied, with fluid produced from: (1) the vapor zone only, (2) the liquid zone only, (3) both zones and (4) both zones, but assuming lower values for vertical permeability and porosity. The results indicate that production from the shallow two phase zone, although resulting in higher enthalpy fluids, may not be advantageous in the long run. Shallow production gives rise to a rather localized depletion of the reservoir, whereas production from deeper horizons may yield a more uniform depletion process, if vertical permeability is sufficiently large.

  5. Improved energy recovery from geothermal reservoirs

    SciTech Connect

    Boedvarsson, G.S.; Pruess, K.; Lippmann, M.; Bjoernsson, S.

    1981-06-01

    Numerical simulation methods are used to study how the exploitation of different horizons affects the behavior of a liquid-dominated geothermal reservoir. The reservoir model is a schematic representation of the Olkaria field in Kenya. The model consists of a two-phase vapor-dominated zone overlying the main liquid dominated reservoir. Four different cases were studied, with fluid produced from: 1) the vapor zone only, 2) the liquid zone only, 3) both zones and 4) both zones, but assuming lower values for vertical permeability and porosity. The results indicate that production from the shallow two-phase zone, although resulting in higher enthalpy fluids, may not be advantageous in the long run. Shallow production gives rise to a rather localized depletion of the reservoir, whereas production from deeper horizons may yield a more uniform depletion proces, if vertical permeability is sufficiently large.

  6. Volume strain within the Geysers geothermal field

    SciTech Connect

    Mossop, Antony; Segall, Paul

    1999-12-10

    During the 1970s and 1980s. The Geysers geothermal region was rapidly developed as a site of geothermal power production. The likelihood that this could cause significant strain within the reservoir, with corresponding surface displacements, led to a series of deformation monitoring surveys. In 1973, 1975, 1977, and 1980, The Geysers region was surveyed using first-order, class I, spirit leveling. In 1994, 1995, and 1996, many of the leveling control monuments were resurveyed using high-precision Global Positioning System receivers. The two survey methods are reconciled using the GEOID96 geoid model. The displacements are inverted to determine volume strain within the reservoir. For the period 1980-1994, peak volume strains in excess of 5x10{sup -4} are imaged. There is an excellent correlation between the observed changes in reservoir steam pressures and the imaged volume strain. If reservoir pressure changes are inducing volume strain, then the reservoir quasi-static bulk modulus K must be <4.6x10{sup 9} Pa. However, seismic velocities indicate a much stiffer reservoir with K=3.4x10{sup 10} Pa. This apparent discrepancy is shown to be consistent with predicted frequency dependence in K for fractured and water-saturated rock. Inversion of surface deformation data therefore appears to be a powerful method for imaging pressure change within the body of the reservoir. Correlation between induced seismicity at The Geysers and volume strain is observed. However, earthquake distribution does not appear to have a simple relationship with volume strain rate. (c) 1999 American Geophysical Union.

  7. Alternative energy sources II; Proceedings of the Second Miami International Conference, Miami Beach, Fla., December 10-13, 1979. Volume 5 - Geothermal power/energy program

    NASA Astrophysics Data System (ADS)

    Veziroglu, T. N.

    This volume examines the geothermal resource and geothermal energy utilization, and surveys regional energy programs worldwide. The particular papers presented on geothermal energy include those on the temperature indicators for geothermal use, geothermal drilling research in the United States, and geothermal energy and biofuel production in agriculture. Energy programs from India, Egypt, Turkey, Greece and Puerto Rico are reviewed.

  8. Investigation of deep permeable strata in the permian basin for future geothermal energy reserves

    SciTech Connect

    Erdlac, Richard J., Jr.; Swift, Douglas B.

    1999-09-23

    This project will investigate a previously unidentified geothermal energy resource, opening broad new frontiers to geothermal development. Data collected by industry during oil and gas development demonstrate deep permeable strata with temperatures {ge} 150 C, within the optimum window for binary power plant operation. The project will delineate Deep Permeable Strata Geothermal Energy (DPSGE) assets in the Permian Basin of western Texas and southeastern New Mexico. Presently, geothermal electrical power generation is limited to proximity to shallow, high-temperature igneous heat sources. This geographically restricts geothermal development. Delineation of a new, less geographically constrained geothermal energy source will stimulate geothermal development, increasing available clean, renewable world energy reserves. This proposal will stimulate geothermal reservoir exploration by identifying untapped and unrealized reservoirs of geothermal energy. DPSGE is present in many regions of the United States not presently considered as geothermally prospective. Development of this new energy source will promote geothermal use throughout the nation.

  9. Industrial application of geothermal energy in southeast Idaho

    NASA Astrophysics Data System (ADS)

    Batdorf, J. A.; McClain, D. W.; Gross, M.; Simmons, G. M.

    1980-02-01

    The main industries in Southeastern Idaho are phosphorus/ phosphate production and potato processing. Most of the energy required in the phosphate industries is electrical and therefore not replaceable by direct application of geothermal energy. The main area for direct use of geothermal energy in the phosphate industry is for drying of the ore at the mine site; however, most of this is energy now supplied by waste heat from the calcining process. There exists a large need for a dedicated supply of electrical energy to these industries and the possibility of using geothermal energy to generate electricity for these areas should be investigated. The potato processing industry uses most of its energy to provide process steam for drying and cooking. Geothermal energy can potentially replace most of these energy requirements provided a high energy source temperature can be located. A 200 F geothermal source could supply about 40% of the industry's needs. A 400 F geothermal source could supply nearly 90% of the industry's needs.

  10. HDR geothermal energy - a progress report

    SciTech Connect

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

    1983-01-01

    A description of the Hot Dry Rock Geothermal Energy Program and a summary of the work completed to date are presented. The Fenton Hill Project is reviewed starting with the research system (Phase I) established in its initial configuration in 1977 with the research work completed in mid-1981. The engineering system (Phase II) initiated in parallel with the completion of the Phase I is now being developed in its interim configuration. The final system is planned for completion in FY 1985 with about one year of testing extending through FY 1986. Technical evaluations and test data to date are encouraging. The foreign involvement (FRG and Japan) is expected to continue along with positive support in the US.

  11. Seismic Activity at tres Virgenes Volcanic and Geothermal Field

    NASA Astrophysics Data System (ADS)

    Antayhua, Y. T.; Lermo, J.; Quintanar, L.; Campos-Enriquez, J. O.

    2013-05-01

    The volcanic and geothermal field Tres Virgenes is in the NE portion of Baja California Sur State, Mexico, between -112°20'and -112°40' longitudes, and 27°25' to 27°36' latitudes. Since 2003 Power Federal Commission and the Engineering Institute of the National Autonomous University of Mexico (UNAM) initiated a seismic monitoring program. The seismograph network installed inside and around the geothermal field consisted, at the beginning, of Kinemetrics K2 accelerometers; since 2009 the network is composed by Guralp CMG-6TD broadband seismometers. The seismic data used in this study covered the period from September 2003 - November 2011. We relocated 118 earthquakes with epicenter in the zone of study recorded in most of the seismic stations. The events analysed have shallow depths (≤10 km), coda Magnitude Mc≤2.4, with epicentral and hypocentral location errors <2 km. These events concentrated mainly below Tres Virgenes volcanoes, and the geothermal explotation zone where there is a system NW-SE, N-S and W-E of extensional faults. Also we obtained focal mechanisms for 38 events using the Focmec, Hash, and FPFIT methods. The results show normal mechanisms which correlate with La Virgen, El Azufre, El Cimarron and Bonfil fault systems, whereas inverse and strike-slip solutions correlate with Las Viboras fault. Additionally, the Qc value was obtained for 118 events. This value was calculated using the Single Back Scattering model, taking the coda-waves train with window lengths of 5 sec. Seismograms were filtered at 4 frequency bands centered at 2, 4, 8 and 16 Hz respectively. The estimates of Qc vary from 62 at 2 Hz, up to 220 at 16 Hz. The frequency-Qc relationship obtained is Qc=40±2f(0.62±0.02), representing the average attenuation characteristics of seismic waves at Tres Virgenes volcanic and geothermal field. This value correlated with those observed at other geothermal and volcanic fields.

  12. Subsidence and uplift at Heber Geothermal field, California

    SciTech Connect

    Boardman, T.S.

    1996-01-01

    Heber Geothermal field is in the Imperial Valley near the City of Heber, California, about 3 1/2 miles north of the Mexican border. The field is at the southern end of a network of irrigated agricultural fields extending across the valley floor. The Heber geothermal system is circular, producing water of moderate temperature (360{degrees}F) and low-salinity (13,000-14,000 ppm TDS). In cross section, the geothermal system resembles a lopsided mushroom. The system has three major permeability units: capping clays form 500 to 1800 feet; a high-matrix-permeability, deltaic-sandstone outflow reservoir from 1,800 to 5,500 feet; and feeder faults and fractures in indurated sediments below 5,500 feet. The deltaic sandstones were deposited by the ancestral Colorado River. As both power plants continue operating in Heber field, the need persists to monitor subsidence and uplift. The field`s subsidence bowl is not expected to expand significantly, but some small changes are expected due to pressure changes caused by production for the SIGC binary power plant. The three SIGC injection wells, located between the production areas for the two power plants, will be managed for adequate reservoir pressure support.

  13. 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)

  14. Joint geophysical data analysis for geothermal energy exploration

    NASA Astrophysics Data System (ADS)

    Wamalwa, Antony Munika

    Geophysical data modelling often yields non-unique results and hence the interpretation of the resulting models in terms of underlying geological units and structures is not a straightforward problem. However, if multiple datasets are available for a region of study, an integrated interpretation of models for each of the geophysical data may results to a more realistic geological description. This study not only demonstrates the strength of resistivity analysis for geothermal fields but also the gains from interpreting resistivity data together with other geophysical data such as gravity and seismic data. Various geothermal fields have been examined in this study which includes Silali and Menengai geothermal fields in Kenya and Coso geothermal field in California, USA.

  15. Comprehensive Cross-Training among STEM Disciplines in Geothermal Energy

    NASA Astrophysics Data System (ADS)

    Nunn, J. A.; Dutrow, B. L.

    2012-12-01

    One of the foremost areas of sustainability is society's need for energy. The US uses more energy per capita than any other country in the world with most of this energy coming from fossil fuels. With its link to climate change coupled with declining resources, renewable alternatives are being pursued. Given the high demand for energy, it is not a question of if these alternatives will be utilized but when and where. One of the "greenest" of the green technologies is geothermal energy. It is a renewable resource with a small environmental footprint. To educate advanced undergraduate and graduate students from across STEM disciplines in geothermal energy, a series of three distinct but linked and related courses are being developed and taught. Courses are focused on one of the STEM disciplines to provide students with essential discipline-specific knowledge and taught by different faculty members in the departments of geology, petroleum engineering and mathematics. These courses provide the foundation necessary for interdisciplinary research projects. The first course on Geologic Properties and Processes of Geothermal Energy was developed and taught in 2012. The class had an enrollment of 27 students including: 5 undergraduates and 4 graduate students in Geology, 12 undergraduates and two graduate students in Petroleum Engineering, and 4 non-matriculated undergraduate students. The course began with the essentials of heat and mass transfer, a common deficiency for all students, then progressed to the geologic materials of these systems: minerals, rocks and fluids. To provide students with first hand experience, two short research projects were embedded into the course. The first project involved analyses of cuttings from a well-studied geothermal system (Salton Sea, CA). Students were in teams consisting of both engineers and geologists. The first assignment was to identify minerals in the cuttings. They were then provided with XRD patterns for their cuttings to

  16. 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.

  17. A Reservoir Assessment of the Geysers Geothermal Field

    SciTech Connect

    Thomas, Richard P.; Chapman, Rodger H.; Dykstra, Herman; Stockton, A.D.

    1981-01-01

    Big Sulphur Creek fault zone, in The Geysers Geothermal field, may be part of a deep-seated, wrench-style fault system. Hydrothermal fluid reservoir may rise through conduits beneath the five main anomalies associated with the Big Sulphur Creek wrench trend. Upon moderately dipping, fracture network. Condensed steam at the steep reservoir flank drains back to the hot water table. These flanks are defined roughly by marginally-producing geothermal wells. Field extensions are expected to be on the southeast and northwest. Some geophysical anomalies (electrical resistivity and audio-magnetotelluric) evidently are caused by the hot water geothermal field or zones of altered rocks; others (gravity, P-wave delays, and possibly electrical resistivity) probably represent the underlying heat source, a possible magma chamber; and others (microearthquake activity) may be related to the steam reservoir. A large negative gravity anomaly and a few low-resitivity anomalies suggest areas generally favorable for the presence of steam zones, but these anomalies apparently do not directly indicate the known steam reservoir. Monitoring gravity and geodetic changes with time and mapping microearthquake activity are methods that show promise for determining reservoir size, possible recharge, production lifetime, and other characteristics of the known stream field. Seismic reflection data may contribute to the efficient exploitation of the field by identifying fracture zones that serve as conduits for the steam. (DJE-2005)

  18. 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.

  19. 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.

  20. New Mexico statewide geothermal energy program. Final technical report

    SciTech Connect

    Icerman, L.; Parker, S.K.

    1988-04-01

    This report summarizes the results of geothermal energy resource assessment work conducted by the New Mexico Statewide Geothermal Energy Program during the period September 7, 1984, through February 29, 1988, under the sponsorship of the US Dept. of Energy and the State of New Mexico Research and Development Institute. The research program was administered by the New Mexico Research and Development Institute and was conducted by professional staff members at New Mexico State University and Lightning Dock Geothermal, Inc. The report is divided into four chapters, which correspond to the principal tasks delineated in the above grant. This work extends the knowledge of the geothermal energy resource base in southern New Mexico with the potential for commercial applications.

  1. Prospects of development of highly mineralized high-temperature resources of the Tarumovskoye geothermal field

    NASA Astrophysics Data System (ADS)

    Alkhasov, A. B.; Alkhasova, D. A.; Ramazanov, A. Sh.; Kasparova, M. A.

    2016-06-01

    The promising nature of integrated processing of high-temperature geothermal brines of the Tarumovskoye geothermal field is shown. Thermal energy of a geothermal brine can be converted to the electric power at a binary geothermal power plant (GPP) based on low-boiling working substance. The thermodynamic Rankine cycles are considered which are implemented in the GPP secondary loop at different evaporation temperatures of the working substance―isobutane. Among them, the most efficient cycle from the standpoint of attaining a maximum power is the supercritical one which is close to the so-called triangular cycle with an evaporation pressure of p e = 5.0 MPa. The used low-temperature brine is supplied from the GPP to a chemical plant, where main chemical components (lithium carbonate, burnt magnesia, calcium carbonate, and sodium chloride) are extracted from it according to the developed technology of comprehensive utilization of geothermal brines of chloride-sodium type. The waste water is delivered to the geotechnological complex and other consumers. For producing valuable inorganic materials, the electric power generated at the GPP is used. Owing to this, the total self-sufficiency of production and independence from external conditions is achieved. The advantages of the proposed geotechnological complex are the full utilization of the heat potential and the extraction of main chemical components of multiparameter geothermal resources. In this case, there is no need for reverse pumping, which eliminates the significant capital costs for building injection wells and a pumping station and the operating costs for their service. A characteristic of the modern state of the field and estimated figures of the integrated processing of high-temperature brines of well no. 6 are given, from which it follows that the proposed technology has a high efficiency. The comprehensive development of the field resources will make it possible to improve the economic structure of the

  2. Geothermal energy exploitation in New Zealand

    SciTech Connect

    Elder, J.W.

    1980-01-01

    The essential factors, human and technical, which control the operation of geothermal systems, particularly those which allow prediction of behavior during and after exploitation, are sketched. The strategy and co-ordination involved in using New Zealand's geothermal resources for power production are considered. The broader aspects of the technical matters involved in the design of the parasitic plant reservoir system are described. (MHR)

  3. Geothermal Systems of the Yellowstone Caldera Field Trip Guide

    SciTech Connect

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

    1980-09-08

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

  4. Characteristics of the Zunil Geothermal Field (Western Guatemala)

    SciTech Connect

    Bethancourt, H.R.; Dominco, E.

    1982-10-01

    The Zunil geothermal field represents the marginal, shallow expression of a vast geothermal complex buried beneath active volcanic edifices (Cerro Quemado, Volcan Santa Maria, Western Guatemala) some kilometers to the west. The area lies at the edge of a tecto-volcanic depression where some 1,000 m of Tertiary and Quaternary volcanics are underlain by a granodioritic basement. High temperature geothermal fluids (over 280/sup 0/C) reach the field from the west, upflowing along the inclined contact between the granodioritic and the overlying volcanics, and along fractures in the basement itself. A conglomeratic layer at the volcanics/basement contact, and the underlying weathered cap of the basement form the only permeable horizon of the succession; this horizon forms the local reservoir tapped by the productive wells. Its reduced thickness (around 50 m) allows for a limited fluid storage such that field production relies on external recharge along the permeable horizon and underlying fractures in the granodiorite. Production testing and simulation models indicate a fairly rapid evolution of reservoir conditions from the liquid to the steam phase, due to pressure drawdown, in its turn due to a restricted inflow. The phenomenon determines an upgrading of the fluid enthalpy, but a decline of mass output. Simulated reinjection into the reservoir proved to be an effective measure to slow down such an evolution and optimize the field exploitation.

  5. An approach for geochemical assessment of Chipilapa geothermal field

    SciTech Connect

    Nieva, D.; Verma, M.P.; Portugal, E.; Torres, V.

    1993-01-28

    It presents a systematic methodology to evaluate the reservoir characteristics of Chipilapa- Ahuachapan geothermal field through the highly diluted natural manifestations (springs and domestic wells) in its surroundings. The manifestations are classified in three main groups according to their mechanism of formation: high salinity water (HSW), medium salinity water (MSW), and Sulfated Water (SW). The reservoir temperature at Chipilapa geothermal field is around 220°C which is estimated with application of various chemical geothermometers. The isotopic studies indicate that the heating of local meteoric water with the separated steam of deep reservoir fluids is a dominating process in the formation of springs and domestic wells fluids. The process of formation of primary and secondary vapor explains the isotopic composition of fumaroles.

  6. Geochemical evaluation and conceptual modeling of the Edremit geothermal field (NW Turkey)

    NASA Astrophysics Data System (ADS)

    Avşar, Özgür; Güleç, Nilgün; Parlaktuna, Mahmut

    2013-04-01

    The Edremit geothermal field is located in the Edremit Graben, which forms an integral part of the Western Anatolian Graben System in Turkey. In the field, the geothermal energy is currently used in heating 5000 houses. A total of 21 wells were sampled in this study for the purpose of hydrogeochemical conceptual modeling. Chemical analyses results indicate that the waters belong to three different types of hydrogeochemical facies, namely Na+K - SO4, Ca - SO4 and Ca - HCO3 type. According to the stable isotope results, all hot and cold waters are meteoric in origin. Radiocarbon dating revealed a positive correlation between the wellhead temperatures and the residence times of waters. "Mixing" and "water rock interaction" are the main subsurface processes that are affecting the water chemistry. By detailed investigation of well logs, two intersecting buried faults are detected in the field. The geothermal system is highly affected by these faults. The groundwater is fed by precipitations on highlands, percolated towards the deeper parts of the crust through deep seated, graben forming step faults, and heated at depth. During its ascent towards surface, geothermal water invades two superimposed aquifers, lower confined and upper unconfined. Mixing between hot and cold waters takes place in the aquifers.

  7. Hot Dry Rock Geothermal Energy Development Program

    SciTech Connect

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

    1989-12-01

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

  8. Hydrogeologic model of the Ahuachapan geothermal field, El Salvador

    SciTech Connect

    Laky, C.; Lippmann, M.J.; Bodvarsson, G.S. ); Retana, M.; Cuellar, G. )

    1989-01-01

    A hydrogeological model of the Ahuachapan geothermal field has been developed. It considers the lithology and structural features of the area and discerns their impact on the movement of cold and hot fluids in the system. Three aquifers were identified, their zones of mixing and flow patterns were obtained on the basis of temperature and geochemical data from wells and surface manifestations. 12 refs., 9 figs.

  9. 3-D analysis and interpretation of magnetotelluric data from the Aluto-Langano geothermal field, Ethiopia

    NASA Astrophysics Data System (ADS)

    Samrock, F.; Kuvshinov, A.; Bakker, J.; Jackson, A.; Fisseha, S.

    2015-09-01

    The Main Ethiopian Rift Valley encompasses a number of volcanoes, which are known to be actively deforming with reoccurring periods of uplift and setting. One of the regions where temporal changes take place is the Aluto volcanic complex. It hosts a productive geothermal field and the only currently operating geothermal power plant of Ethiopia. We carried out magnetotelluric (MT) measurements in early 2012 in order to identify the source of unrest. Broad-band MT data (0.001-1000 s) have been acquired at 46 sites covering the expanse of the Aluto volcanic complex with an average site spacing of 1 km. Based on this MT data it is possible to map the bulk electrical resistivity of the subsurface down to depths of several kilometres. Resistivity is a crucial geophysical parameter in geothermal exploration as hydrothermal and magmatic reservoirs are typically related to low resistive zones, which can be easily sensed by MT. Thus by mapping the electrical conductivity one can identify and analyse geothermal systems with respect to their temperature, extent and potential for production of energy. 3-D inversions of the observed MT data from Aluto reveal the typical electrical conductivity distribution of a high-enthalpy geothermal system, which is mainly governed by the hydrothermal alteration mineralogy. The recovered 3-D conductivity models provide no evidence for an active deep magmatic system under Aluto. Forward modelling of the tippers rather suggest that occurrence of melt is predominantly at lower crustal depths along an off-axis fault zone a few tens of kilometres west of the central rift axis. The absence of an active magmatic system implies that the deforming source is most likely situated within the shallow hydrothermal system of the Aluto-Langano geothermal field.

  10. Geothermal Heat Pump Profitability in Energy Services

    SciTech Connect

    1997-11-01

    If geothermal heat pumps (GHPs) are to make a significant mark in the market, we believe that it will be through energy service pricing contracts offered by retailcos. The benefits of GHPs are ideally suited to energy service pricing (ESP) contractual arrangements; however, few retailcos are thoroughly familiar with the benefits of GHPs. Many of the same barriers that have prevented GHPs from reaching their full potential in the current market environment remain in place for retailcos. A lack of awareness, concerns over the actual efficiencies of GHPs, perceptions of extremely high first costs, unknown records for maintenance costs, etc. have all contributed to limited adoption of GHP technology. These same factors are of concern to retailcos as they contemplate long term customer contracts. The central focus of this project was the creation of models, using actual GHP operating data and the experience of seasoned professionals, to simulate the financial performance of GHPs in long-term ESP contracts versus the outcome using alternative equipment. We have chosen two case studies, which may be most indicative of target markets in the competitive marketplace: A new 37,000 square foot office building in Toronto, Ontario; we also modeled a similar building under the weather conditions of Orlando, Florida. An aggregated residential energy services project using the mass conversion of over 4,000 residential units at Ft. Polk, Louisiana. Our method of analyses involved estimating equipment and energy costs for both the base case and the GHP buildings. These costs are input in to a cash flow analysis financial model which calculates an after-tax cost for the base and GHP case. For each case study customers were assumed to receive a 5% savings over their base case utility bill. A sensitivity analysis was then conducted to determine how key variables affect the attractiveness of a GHP investment.

  11. Institutional and environmental aspects of geothermal energy development

    NASA Technical Reports Server (NTRS)

    Citron, O. R.

    1977-01-01

    Until recently, the majority of work in geothermal energy development has been devoted to technical considerations of resource identification and extraction technologies. The increasing interest in exploiting the variety of geothermal resources has prompted an examination of the institutional barriers to their introduction for commercial use. A significant effort was undertaken by the Jet Propulsion Laboratory as a part of a national study to identify existing constraints to geothermal development and possible remedial actions. These aspects included legislative and legal parameters plus environmental, social, and economic considerations.

  12. Recency of Faulting and Neotechtonic Framework in the Dixie Valley Geothermal Field and Other Geothermal Fields of the Basin and Range

    SciTech Connect

    Steven Wesnousky; S. John Caskey; John W. Bell

    2003-02-20

    We studied the role that earthquake faults play in redistributing stresses within in the earths crust near geothermal fields. The geographic foci of our study were the sites of geothermal plants in Dixie Valley, Beowawe, and Bradys Hot Springs, Nevada. Our initial results show that the past history of earthquakes has redistributed stresses at these 3 sites in a manner to open and maintain fluid pathways critical for geothermal development. The approach developed here during our pilot study provides an inexpensive approach to (1) better define the best locations to site geothermal wells within known geothermal fields and (2) to define the location of yet discovered geothermal fields which are not manifest at the surface by active geothermal springs. More specifically, our investigation shows that induced stress concentrations at the endpoints of normal fault ruptures appear to promote favorable conditions for hydrothermal activity in two ways. We conclude that an understanding of the spatial distribution of active faults and the past history of earthquakes on those faults be incorporated as a standard tool in geothermal exploration and in the siting of future boreholes in existing geothermal fields.

  13. 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.

  14. 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.

  15. Strategies and Perceptions of Students' Field Note-Taking Skills: Insights from a Geothermal Field Lesson

    ERIC Educational Resources Information Center

    Dohaney, Jacqueline; Brogt, Erik; Kennedy, Ben

    2015-01-01

    Field note-taking skills are fundamental in the geosciences but are rarely explicitly taught. In a mixed-method study of an introductory geothermal field lesson, we characterize the content and perceptions of students' note-taking skills to derive the strategies that students use in the field. We collected several data sets: observations of the…

  16. Geothermal Energy Research Development and Demonstration Program

    SciTech Connect

    Not Available

    1980-06-01

    The Federal program's goal, strategy, plans, and achievements are summarized. In addition, geothermal development by state and local governments and, where available, by the private sector is described. (MHR)

  17. Geothermal Data Collection and Interpretation in the State of Alabama: Early Results from the ARRA Geothermal Energy Initiative

    NASA Astrophysics Data System (ADS)

    Hills, D. J.; Osborne, T. E.; McIntyre, M. R.; Pashin, J. C.

    2011-12-01

    The Geological Survey of Alabama (GSA) is expanding its efforts to collect, develop, maintain, and analyze statewide geothermal data and to make this information widely and easily accessible to the public through the National Geothermal Data System. The online availability of this data will aid in the effective development of geothermal energy applications and reduce the risks associated with the initial stages of geothermal project development. To this end, the GSA is participating in a collaborative project that the Arizona Geological Survey is coordinating in cooperation with the Association of American State Geologists and with the support of the U.S. Department of Energy as part of the American Reinvestment and Recovery Act. Wells drilled for the exploration and production of hydrocarbons are the primary sources of geothermal data in Alabama. To date, more than 1,200 wells in coalbed methane (CBM) fields in the Black Warrior Basin (BWB) have been examined, in addition to over 500 conventional wells in the basin. Pottsville Formation (Pennsylvanian) bottom-hole temperatures (BHTs) range from less than 80°F to more than 140°F in wells reaching total depth between 1,000 and 6,000 feet (ft). Temperature and depth correlate with a coefficient of determination (r2) of 0.72, reflecting significant variation of the modern geothermal gradient. Mapping and statistical analysis confirm that geothermal gradient in the CBM fairway is typically between 6 and 12°F/1,000 ft. BHTs in the conventional wells penetrating the BWB show even greater variation, with temperature and depth correlating with an r2 of only 0.27. This variability owes to numerous factors, including stratigraphy, lithology, thermal conductivity, and geothermal gradient. Indeed, these wells reach total depth between 500 and 12,000 ft in carbonate and siliciclastic formations ranging in age from Cambrian to Mississippian. The Cambrian section is dominated by low conductivity shale, whereas the Ordovician

  18. Energy Return On Investment of Engineered Geothermal Systems Data

    DOE Data Explorer

    Mansure, Chip

    2012-01-01

    The project provides an updated Energy Return on Investment (EROI) for Enhanced Geothermal Systems (EGS). Results incorporate Argonne National Laboratory's Life Cycle Assessment and base case assumptions consistent with other projects in the Analysis subprogram. EROI is a ratio of the energy delivered to the consumer to the energy consumed to build, operate, and decommission the facility. EROI is important in assessing the viability of energy alternatives. Currently EROI analyses of geothermal energy are either out-of-date, of uncertain methodology, or presented online with little supporting documentation. This data set is a collection of files documenting data used to calculate the Energy Return On Investment (EROI) of Engineered Geothermal Systems (EGS) and erratum to publications prior to the final report. Final report is available from the OSTI web site (http://www.osti.gov/geothermal/). Data in this collections includes the well designs used, input parameters for GETEM, a discussion of the energy needed to haul materials to the drill site, the baseline mud program, and a summary of the energy needed to drill each of the well designs. EROI is the ratio of the energy delivered to the customer to the energy consumed to construct, operate, and decommission the facility. Whereas efficiency is the ratio of the energy delivered to the customer to the energy extracted from the reservoir.

  19. 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.

  20. The Advancement of Geothermal Energy Production through Improved Exploration Methods

    NASA Astrophysics Data System (ADS)

    Thorsteinsson, H.; Klein, K.

    2010-12-01

    Through the American Recovery and Reinvestment Act of 2009, the U.S. Department of Energy’s Geothermal Technologies Program invested $98 million in the geothermal exploration industry, and continues to encourage further research, development and demonstration in this field. The continued development of innovative exploration technologies is essential for wide adoption of geothermal resources. In 2008, the United States Geological Survey estimated that there are approximately 30,000 MW of undiscovered hydrothermal resources in the western United States alone. Improvements in exploration technologies are necessary to discover and define these hidden resources and to reduce up-front risk and cost through more accurate and efficient exploration. Currently, the surface and subsurface are characterized through combinations of ground-based and airborne geophysical surveys, geochemical surveys, satellite imaging and drilling. However, to increase geothermal exploration well success rates, development of improved and new exploration techniques is required.

  1. Geothermal energy: opportunities for California commerce. Phase I report

    SciTech Connect

    Not Available

    1982-01-01

    California's geographic and end-use markets which could directly use low and moderate temperature geothermal resources are ranked and described, as well as those which have the highest potential for near-term commercial development of these resources. Building on previous market surveys, the assessment determined that out of 38 geothermal resource areas with characteristics for direct use development, five areas have no perceived impediments to near-term development: Susanville, Litchfield, Ontario Hot Springs, Lake Elsinore, and the Salton Sea Geothermal Field. Twenty-nine applications were compared with previously selected criteria to determine their near-term potential for direct use of geothermal fluids. Seven categories were found to have the least impediments to development; agriculture and district heating applications are considered the highest. Ten-year projections were conducted for fossil fuel displacement from the higher rated applications. It is concluded that greenhouses have the greatest displacement of 18 x 10/sup 6/ therms per year.

  2. 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)

  3. Innovations in the financing of geothermal energy for direct-use applications

    SciTech Connect

    Kwass, P.

    1981-10-01

    The applications of direct use geothermal energy, its advantages, and its relative costs are examined. The following are discussed: capital needs for direct-use geothermal development, sources of geothermal financing, barriers to geothermal financing, and selected case studies of curent financing alternatives.

  4. Gas geochemistry of the Geysers geothermal field

    SciTech Connect

    Truesdell, A.H.

    1993-04-01

    Increases in gas concentrations in Central and Southeast Geysers steam are related to the decreases in pressure caused by heavy exploitation in the 1980s. When reservoir pressures in the central parts of the field decreased, high-gas steam from undrilled reservoir margins (and possibly from underlying high-temperature zones) flowed into exploited central areas. The Northwest Geysers reservoir probably lacks high-gas marginal steam and a decline in pressure may not cause a significant increase of gas concentrations in produced steam.

  5. Market penetration analysis for direct heat geothermal energy applications

    SciTech Connect

    Thomas, R.J.; Nelson, R.A.

    1981-06-01

    This study is concerned with the estimation of the National geothermal market potential and penetration in direct heat applications for residences and certain industry segments. An important aspect of this study is that the analysis considers both known and anticipated goethermal resources. This allows for an estimation of the longer-range potential for geothermal applications. Thus the approach and results of this study provide new insights and valuable information not obtained from more limited, site-specific types of analyses. Estimates made in this study track geothermal market potential and projected penetration from the present to the year 2020. Private sector commercialization of geothermal energy over this period requires assistance in the identification of markets and market sizes, potential users, and appropriate technical applications.

  6. Hydrothermal surface alteration in the Copahue Geothermal Field (Argentina)

    SciTech Connect

    Mas, Graciela R.; Mas, Luis C.; Bengochea, Leandro

    1996-01-24

    In the area of the Copahue Geothermal Field, there are five active geothermal manifestations, which mainly consist of fumaroles, hot springs and mud pots. Four of these manifestations are located in Argentina: Las Máquinas, Termas de Copahue, Las Maquinitas and El Anfiteatro, and the fifth on the Chilean side: Chancho Co. All of them present a strong acid sulfate country rock alteration, characterized by the assemblage alunite + kaolinite + quartz + cristobalite + pyrite + sulfur + jarosite, as the result of the base leaching by fluids concentrated in H2SO4 by atmospheric oxidation at the water table in a steam heated environment of H2S released by deeper boiling fluids. Another alteration zone in this area, called COP-2, is a fossil geothermal manifestation which shows characteristics of neutral to alkaline alteration represented mainly by the siliceous sinter superimposed over the acid alteration. The mineralogy and zoning of these alteration zones, and their relation with the hidrothermal solutions and the major structures of the area are analized.

  7. Hydrothermal surface alteration in the Copahue Geothermal Field (Argentina)

    SciTech Connect

    Mas, G.R.; Bengochea, L.; Mas, L.C.

    1996-12-31

    In the area of the Copahue Geothermal Field, there are five active geothermal manifestations, which mainly consist of fumaroles, hot springs and mud pots. Four of these manifestations are located in Argentina: Las Maquinas, Tennas de Copahue, Las Maquinitas and El Anfiteatro, and the fifth on the Chilean side: Chancho Co. All of them present a strong acid sulfate country rock alteration, characterized by the assemblage alunite + kaolinite + quartz + cristobalite + pyrite + sulfur + jarosite, as the result of the base leaching by fluids concentrated in H{sub 2}SO{sub 4}, by atmospheric oxidation at the water table in a steam heated environment of H{sub 2}S released by deeper boiling fluids. Another alteration zone in this area, called COP-2, is a fossil geothermal manifestation which shows characteristics of neutral to alkaline alteration represented mainly by the siliceous sinter superimposed over the acid alteration. The mineralogy and zoning of these alteration zones, and their relation with the hydrothermal solutions and the major structures of the area are analyzed.

  8. A database for The Geysers geothermal field

    SciTech Connect

    Bodvarsson, G.S.; Cox, B.L.; Fuller, P.; Ripperda, M.; Tulinius, H.; Witherspoon, P.A.; Goldstein, N.; Flexser, S.; Pruess, K. ); Truesdell, A. )

    1989-09-01

    In Fiscal Year 1985-1986 the Earth Sciences Division of Lawrence Berkeley Laboratory (LBL) began a multi-year project for SLC to organize and analyze the field data from The Geysers. In the first year, most of the work concentrated on the development of a comprehensive database for The Geysers, and conventional reservoir engineering analysis of the data. Essentially, all non-proprietary data for wells at The Geysers have been incorporated into the database, as well as proprietary data from wells located on State leases. In following years, a more detailed analysis of The Geysers data has been carried out. This report is a summary of the non- proprietary work performed in FY 1985--1986. It describes various aspects of the database and also includes: review sections on Field Development, Geology, Geophysics, Geochemistry and Reservoir Engineering. It should be emphasized that these background chapters were written in 1986, and therefore only summarize the information available at that time. The appendices contain individual plots of wellhead pressures, degree of superheat, steam flow rates, cumulative mass flows, injection rates and cumulative injection through 1988 for approximately 250 wells. All of the data contained in this report are non-proprietary, from State and non-State leases. The production/injection and heat flow data from the wells were obtained from the California State Division of Oil and gas (DOG) (courtesy of Dick Thomas). Most of the other data were obtained from SLC files in Sacramento (courtesy of Charles Priddy), or DOG files in Santa Rosa (courtesy of Ken Stelling). 159 refs., 23 figs., 3 tabs.

  9. Seismicity and coupled deformation modeling at the Coso Geothermal Field

    NASA Astrophysics Data System (ADS)

    Kaven, J. O.; Hickman, S. H.; Davatzes, N. C.

    2015-12-01

    Micro-seismicity in geothermal reservoirs, in particular in enhanced geothermal systems (EGS), is a beneficial byproduct of injection and production, as it can indicate the generation of high-permeability pathways on either pre-existing or newly generated faults and fractures. The hazard of inducing an earthquake large enough to be felt at the surface, however, is not easily avoided and has led to termination of some EGS projects. To explore the physical processes leading to permeability creation and maintenance in geothermal systems and the physics of induced earthquakes , we investigated the evolution of seismicity and the factors controlling the migration, moment release rate, and timing of seismicity in the Coso Geothermal Field (CGF). We report on seismicity in the CGF that has been relocated with high precision double-difference relocation techniques and simultaneous velocity inversions to understand hydrologic reservoir compartmentalization and the nature of subsurface boundaries to fluid flow. We find that two distinct compartments are present within the CGF, which are divided by an aseismic gap showing a relatively low Vp/Vs ratio, likely indicating lower temperatures or lower pore pressures within the gap than in the adjacent reservoir compartments. Well-located events with Mw> 3.5 tend to map onto reactivated fault structures that were revealed when imaged by the relocated micro-seismicity. We relate the temporal and spatial migration of moment release rate to the injection and production histories in the reservoir by employing a thermo-poro-elastic finite element model that takes into account the compartment boundaries defined by the seismicity. We find that pore pressure effects alone are not responsible for the migration of seismicity and that poro-elastic and thermo-elastic stress changes are needed in addition to fluid pressure effects to account for the observed moment release rates.

  10. Field testing advanced geothermal turbodrill (AGT). Phase 1 final report

    SciTech Connect

    Maurer, W.C.; Cohen, J.H.

    1999-06-01

    Maurer Engineering developed special high-temperature geothermal turbodrills for LANL in the 1970s to overcome motor temperature limitations. These turbodrills were used to drill the directional portions of LANL`s Hot Dry Rock Geothermal Wells at Fenton Hill, New Mexico. The Hot Dry Rock concept is to drill parallel inclined wells (35-degree inclination), hydraulically fracture between these wells, and then circulate cold water down one well and through the fractures and produce hot water out of the second well. At the time LANL drilled the Fenton Hill wells, the LANL turbodrill was the only motor in the world that would drill at the high temperatures encountered in these wells. It was difficult to operate the turbodrills continuously at low speed due to the low torque output of the LANL turbodrills. The turbodrills would stall frequently and could only be restarted by lifting the bit off bottom. This allowed the bit to rotate at very high speeds, and as a result, there was excessive wear in the bearings and on the gauge of insert roller bits due to these high rotary speeds. In 1998, Maurer Engineering developed an Advanced Geothermal Turbodrill (AGT) for the National Advanced Drilling and Excavation Technology (NADET) at MIT by adding a planetary speed reducer to the LANL turbodrill to increase its torque and reduce its rotary speed. Drilling tests were conducted with the AGT using 12 1/2-inch insert roller bits in Texas Pink Granite. The drilling tests were very successful, with the AGT drilling 94 ft/hr in Texas Pink Granite compared to 45 ft/hr with the LANL turbodrill and 42 ft/hr with a rotary drill. Field tests are currently being planned in Mexico and in geothermal wells in California to demonstrate the ability of the AGT to increase drilling rates and reduce drilling costs.

  11. National Geothermal Data System: Interactive Assessment of Geothermal Energy Potential in the U.S.

    SciTech Connect

    Allison, Lee; Richard, Stephen; Clark, Ryan; Patten, Kim; Love, Diane; Coleman, Celia; Chen, Genhan; Matti, Jordan; Pape, Estelle; Musil, Leah

    2012-01-30

    Geothermal-relevant geosciences data from all 50 states (www.stategeothermaldata.org), federal agencies, national labs, and academic centers are being digitized and linked in a distributed online network via the U.S. Department of Energy-funded National Geothermal Data System (NGDS) to foster geothermal energy exploration and development through use of interactive online ‘mashups,’data integration, and applications. Emphasis is first to make as much information as possible accessible online, with a long range goal to make data interoperable through standardized services and interchange formats. An initial set of thirty geoscience data content models is in use or under development to define a standardized interchange format: aqueous chemistry, borehole temperature data, direct use feature, drill stem test, earthquake hypocenter, fault feature, geologic contact feature, geologic unit feature, thermal/hot spring description, metadata, quaternary fault, volcanic vent description, well header feature, borehole lithology log, crustal stress, gravity, heat flow/temperature gradient, permeability, and feature descriptions data like developed geothermal systems, geologic unit geothermal properties, permeability, production data, rock alteration description, rock chemistry, and thermal conductivity. Map services are also being developed for isopach maps, aquifer temperature maps, and several states are working on geothermal resource overview maps. Content models are developed preferentially from existing community use in order to encourage widespread adoption and promulgate minimum metadata quality standards. Geoscience data and maps from other NGDS participating institutions, or “nodes” (USGS, Southern Methodist University, Boise State University Geothermal Data Coalition) are being supplemented with extensive land management and land use resources from the Western Regional Partnership (15 federal agencies and 5 Western states) to provide access to a comprehensive

  12. The Ngatamariki Geothermal Field, NZ: Surface Manifestations - Past and Present

    SciTech Connect

    Brotheridge, J.M.A.; Browne, P.R.L.; Hochstein, M.P.

    1995-01-01

    The Ngatamariki geothermal field, located 7 km south of Orakeikorako, discharges dilute chloride-bicarbonate waters of almost neutral pH from springs mostly on the margins of the field. Rhyolite tuffs in the northwestern part of the field are weakly silicified, probably due to their having reacted with heated groundwaters. Sinter deposits are common at Ngatamariki but are mostly relict from former activity. In 1994, the natural heat loss from the field was 30 {+-} 5 MW{sub thermal}. There has been a shift of thermal activity southward over the past 60 years; the changes were recognized by comparing air photographs taken in 1941 and 1991. In 1948, a hydrothermal eruption deposited breccia around its crater, which is now occupied by a pool at 52.5 C. Another pool at 88 C, first noticed in 1993, deposits a mixture of silica and calcite.

  13. Don't forget alternate energy sources: biomass, geothermal, wind

    SciTech Connect

    Miskell, J.T.

    1981-01-01

    The United States is probably the most fortunate country in the world in terms of potential energy resources, and that is part of the problem in developing alternate sources. Which ones should be given preference, and which ones will give the quickest, most economic return on investment. The exploration of converting potential plant life to energy is already underway. One such plant is the milkweed. The milky latex substance of the weed contains 30% hydrocarbon and 70% water. About 7% to 10% of the plant weight is extractable crude oil. The unused plant residue can be processed to produce alcohol. In Utah, a milkweed project yielded 2.5 pounds of oil from 35 lbs. of milkweed. The California Commission is looking into the possibility of using two million tons of rice straw, now left in the fields to be burned. The basic thrust of geothermal activity is still the dry steam plants in the Geyser field in California, but the movement to develop more prevalent hot water persists. Binary production and the use of moderate hot water are gaining in acceptance. The government's goal for wind for the year 2000 is 2% of total energy usage. Both utility and consumer participation will be required to meet that goal. Utilities will have to install 20,000 to 30,000 large-scale machines and nearly 1 million would have to be installed by consumers for homes and farms. Movement is already underway.

  14. Geothermal resource requirements for an energy self-sufficient spaceport

    SciTech Connect

    Kruger, P.; Fioravanti, M.; Duchane, D.; Vaughan, A.

    1997-01-01

    Geothermal resources in the southwestern United States provide an opportunity for development of isolated spaceports with local energy self-sufficiency. Geothermal resources can provide both thermal energy and electrical energy for the spaceport facility infrastructure and production of hydrogen fuel for the space vehicles. In contrast to hydrothermal resources by which electric power is generated for sale to utilities, hot dry rock (HDR) geothermal resources are more wide-spread and can be more readily developed at desired spaceport locations. This paper reviews a dynamic model used to quantify the HDR resources requirements for a generic spaceport and estimate the necessary reservoir size and heat extraction rate. The paper reviews the distribution of HDR resources in southern California and southern New Mexico, two regions where a first developmental spaceport is likely to be located. Finally, the paper discusses the design of a HDR facility for the generic spaceport and estimates the cost of the locally produced power.

  15. Utilization of geothermal energy in a pulp and paper mill

    SciTech Connect

    Hotson, G.W.

    1997-01-01

    The Tasman Pulp and Paper Company Ltd.`s Mill at Kawerau, New Zealand, has been utilizing geothermal energy for more than 30 years. The mill produces approximately 200,000 tonnes of kraft pulp and 400,000 tonnes of newsprint per annum. Geothermal energy produces 26% of the process steam requirements and 6% of the mill`s electrical load. The management of the mill`s energy sources is complex and ever changing, which has resulted in unique control strategies being developed over the years to improve efficiencies in the operation of the plant. Complete utilization of the geothermal resource has been the aim of the company and has led to pioneering plant and process developments.

  16. 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.

  17. Pressure Buildup Analysis for Two-Phase Geothermal Wells: Application to the Baca Geothermal Field

    NASA Astrophysics Data System (ADS)

    Riney, T. D.; Garg, S. K.

    1985-03-01

    The recently published pressure transient analysis methods for two-phase geothermal wells are employed to analyze the pressure buildup data for several wells located in the Redondo Creek area of the Baca geothermal field in New Mexico. The downhole drilling information and pressure/temperature surveys are first interpreted to locate zones at which fluid enters the well bore from the formation and to estimate the initial reservoir temperature and pressure in these zones. All of the Baca wells considered here induced flashing in the formation upon production. Interpretation of the buildup data for each well considers well bore effects (e.g., phase change in the well bore fluid and location of the pressure sensor with respect to the permeable horizon) and the carbon dioxide content of the fluid and its effects on the phase behavior of the reservoir fluids and differentiates between the single- and two-phase portions of the pressure buildup data. Different straight-line approximations to the two portions (i.e., single- and two-phase) of the data on the Homer plot are used to obtain corresponding estimates for the single- and two-phase mobilities. Estimates for the formation permeability-thickness (kH) product are also given.

  18. Reflection seismic imaging in the volcanic area of the geothermal field Wayang Windu, Indonesia

    NASA Astrophysics Data System (ADS)

    Polom, Ulrich; Wiyono, Wiyono; Pramono, Bambang; Krawczyk, CharLotte M.

    2014-05-01

    Reflection seismic exploration in volcanic areas is still a scientific challenge and requires major efforts to develop imaging workflows capable of an economic utilization, e.g., for geothermal exploration. The SESaR (Seismic Exploration and Safety Risk study for decentral geothermal plants in Indonesia) project therefore tackles still not well resolved issues concerning wave propagation or energy absorption in areas covered by pyroclastic sediments using both active P-wave and S-wave seismics. Site-specific exploration procedures were tested in different tectonic and lithological regimes to compare imaging conditions. Based on the results of a small-scale, active seismic pre-site survey in the area of the Wayang Windu geothermal field in November 2012, an additional medium-scale active seismic experiment using P-waves was carried out in August 2013. The latter experiment was designed to investigate local changes of seismic subsurface response, to expand the knowledge about capabilities of the vibroseis method for seismic surveying in regions covered by pyroclastic material, and to achieve higher depth penetration. Thus, for the first time in the Wayang Windu geothermal area, a powerful, hydraulically driven seismic mini-vibrator device of 27 kN peak force (LIAG's mini-vibrator MHV2.7) was used as seismic source instead of the weaker hammer blow applied in former field surveys. Aiming at acquiring parameter test and production data southeast of the Wayang Windu geothermal power plant, a 48-channel GEODE recording instrument of the Badan Geologi was used in a high-resolution configuration, with receiver group intervals of 5 m and source intervals of 10 m. Thereby, the LIAG field crew, Star Energy, GFZ Potsdam, and ITB Bandung acquired a nearly 600 m long profile. In general, we observe the successful applicability of the vibroseis method for such a difficult seismic acquisition environment. Taking into account the local conditions at Wayang Windu, the method is

  19. Fracture patterns in graywacke outcrops at The Geysers geothermal field

    SciTech Connect

    Sammis, Charles G.; Lin Ji An; Ershaghi, I.

    1991-01-01

    The Geysers geothermal field covers an area of more than 35,000 acres and represents one of the most significant steam fields in the world. The heterogeneous nature of the reservoir, its fracture network and non-sedimentary rock distinguish it from ordinary sandstone reservoirs in terms of reservoir definition and evaluation (Stockton et al. 1984). Analysis of cuttings, record of steam entries, temperature and pressure surveys and spinner logs have contributed to an understanding of the subsurface geology and rock characteristics of the Geysers. Few conventional electrical log data are available for the main body of the reservoir. It is generally believed that while the fractures are the main conducts for fluid transport through the reservoirs, tight rocks between the major fractures contain the bulk of the fluid reserves. No independent measurement of liquid and vapor saturation can be made from the existing downhole tools. Pressure depletion in The Geysers geothermal field has become a major concern to the operators and utility companies in recent years. Plans for further development activities and future field management are contingent upon accurate computer modeling and definition of the field. The primary issues in reliable characterization of The Geysers field are the role of the rock matrix in holding liquid reserves and providing pressure support, the nature of fracture network, extent of liquid saturation in the reservoirs and injection pattern strategies to maximize heat recovery. Current modeling of The Geysers field is done through the use of general purpose geothermal reservoir simulators. Approaches employed include treating the reservoir as a single porosity equivalent or a dual porosity system. These simulators include formulation to represent transport of heat, steam and water. Heterogeneities are represented by spatial variations in formation or fracture permeability-thickness product, porosity or fluid saturations. Conceptual models based on dual

  20. Improved Detection of Microearthquakes: Application of Matched Field Processing (MFP) to Traditional and Enhanced Geothermal Systems

    NASA Astrophysics Data System (ADS)

    Templeton, D. C.; Harris, D.; Goebel, M.

    2013-12-01

    We investigate the microseismicity in both traditional and Enhanced Geothermal Systems (EGS) and compare the temporal distribution of microseismic events to well fluid injection data. We apply the empirical and model-based Matched Field Processing (MFP) methods to continuous seismic data from the Salton Sea geothermal field and the DOE Newberry EGS site. MFP is a non-traditional event detection method that can identify more and smaller events than traditional detection methods alone. The empirical MFP method uses known catalog events as master templates to identify new microearthquakes while the model-based MFP method uses synthetic sources computed across a subsurface 3D grid as master templates. Salton Sea data between January 2008 and December 2011 was downloaded off the SCEDC website and high-quality master events were identified from the online catalog. We created empirical matched field steering vector calibrations for 7 three-component stations within the Salton Sea Geothermal Field. The original Salton Sea earthquake catalog identified 4202 events. When we applied the empirical MFP technique to the same data, we identified 5005 additional events (~119% more events). We compare the results from this traditional geothermal area with results obtained from the Newberry EGS site, for which we have 8 three-component stations. The Newberry catalog originally identified 204 events in 3 months while the MFP technique identified 249 additional events (~122% more events). We will compare the results from using the empirical MFP method at the Newberry EGS site with results obtained from using model-based master templates. Additionally, we compare the number of events in the improved earthquake catalogs with available fluid injection data. This work is performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  1. Neutron radigoraphy of fluid flow for geothermal energy research

    SciTech Connect

    Bingham, Philip R.; Polsky, Yarom; Anovitz, L.; Carmichael, Justin R.; Bilheux, Hassina Z; Jacobson, David; Hussey, Dan

    2015-01-01

    Enhanced geothermal systems seek to expand the potential for geothermal energy by engineering heat exchange systems within the earth. A neutron radiography imaging method has been developed for the study of fluid flow through rock under environmental conditions found in enhanced geothermal energy systems. For this method, a pressure vessel suitable for neutron radiography was designed and fabricated, modifications to imaging instrument setups were tested, multiple contrast agents were tested, and algorithms developed for tracking of flow. The method has shown success for tracking of single phase flow through a manufactured crack in a 3.81 cm (1.5 inch) diameter core within a pressure vessel capable of confinement up to 69 MPa (10,000 psi) using a particle tracking approach with bubbles of fluorocarbon-based fluid as the “particles” and imaging with 10 ms exposures.

  2. NEDO'S project on geothermal reservoir engineering -- a reservoir engineering study of the Kirishima field, Japan

    SciTech Connect

    Kitamura, H.; Ishido, T.; Miyazaki, S.; Abe, I.; Nobumoto, R.

    1988-01-01

    In order to promote the development of geothermal energy resources, it is important to understand and (to the extent possible) to alleviate potential risks associated with each proposed development project. Further, it is essential to estimate the generation capacity of the reservoir prior to full-scale commitment so that the power plant design may be intelligently formulated. Starting in 1984, the New Energy Development Organization (NEDO) in Japan undertook a four-year program to develop technical methods for the evaluation of potential geothermal resources and for the prediction of production capacity and the appropriate level of electrical generation to be anticipated. NEDO’s general approach to theoretical reservoir evaluation is described, as is the schedule and progress along the four-year program toward its four main goals: development of reservoir simulators, drilling of observation wells in two model fields (the Sumikawa field in northern Honshu and the Kirishima field in southern Kyushu), well tests in the model fields, and reservoir simulation with natural-state and production calculation for both fields. The remainder of the paper describes some results obtained from the well testing program in the Kirishima field and ongoing studies of it.

  3. Improved Detection of Microearthquakes in Geothermal Areas - Applying Empirical Matched Field Processing to Traditional and EGS sites

    NASA Astrophysics Data System (ADS)

    Templeton, D. C.; Wang, J.; Harris, D. B.

    2012-12-01

    The aim of this project is to increase the amount of information that can be extracted from seismic data collected in EGS or traditional geothermal areas. To accomplish our objective, we develop a seismic imaging technique that can map seismicity from discrete microearthquake sources using the Matched Field Processing (MFP) method. We use data from the Salton Sea geothermal field available from the Southern California Earthquake Data Center. Data between November 2009 and December 2010 was downloaded off the web and 231 high-quality master events were identified from the online catalog. This time period included two robust earthquake swarms. We created matched field steering vector calibrations for 7 three-component stations within the Salton Sea Geothermal Field. The official earthquake catalog identified 1536 events. When we applied the empirical MFP technique to the same data, we identified 5357 events. We then compare the results from this traditional geothermal area with results obtained from an Engineered Geothermal System (EGS) site. Finally, we compare the number of events in the improved earthquake catalogs with available fluid injection data. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  4. Geothermal energy planning and communication for native Americans. Final report. Draft

    SciTech Connect

    Robertson, T.A.

    1982-03-30

    The purpose was to explore and develop geothermal energy resources on Indian lands. Activities included the following: (1) continued review of Indian communities and their potential for geothermal energy development; (2) introduced tribes to the availability of geothermal energy and removed the barriers to the implementation of this energy source; (3) provided information by telephone and by mailing packages of information; (4) published articles on geothermal energy development in the UIPA newsletter and supplied articles to other Indian publication; (5) conducted two seminars specific to geothermal energy development on Indian lands in western states; (6) carried out survey of Indian attitudes and opinions toward energy in general and geothermal energy in specific; (7) incorporated geothermal energy development information in Economic Development Administration sponsored tribal government management programs, and (8) developed draft written material addressing Indian planning problems and supporting their ability to affect a more productive working relationship with government agencies and reduced dependency.

  5. Advanced Horizontal Well Recirculation Systems for Geothermal Energy Recovery in Sedimentary Formations

    SciTech Connect

    Mike Bruno; Russell L. Detwiler; Kang Lao; Vahid Serajian; Jean Elkhoury; Julia Diessl; Nicky White

    2012-09-30

    There is increased recognition that geothermal energy resources are more widespread than previously thought, with potential for providing a significant amount of sustainable clean energy worldwide. Recent advances in drilling, completion, and production technology from the oil and gas industry can now be applied to unlock vast new geothermal resources, with some estimates for potential electricity generation from geothermal energy now on the order of 2 million megawatts. Terralog USA, in collaboration with the University of California, Irvine (UCI), are currently investigating advanced design concepts for paired horizontal well recirculation systems, optimally configured for geothermal energy recovery in permeable sedimentary and crystalline formations of varying structure and material properties. This two-year research project, funded by the US Department of Energy, includes combined efforts for: 1) Resource characterization; 2) Small and large scale laboratory investigations; 3) Numerical simulation at both the laboratory and field scale; and 4) Engineering feasibility studies and economic evaluations. The research project is currently in its early stages. This paper summarizes our technical approach and preliminary findings related to potential resources, small-scale laboratory simulation, and supporting numerical simulation efforts.

  6. Direct use of geothermal energy around the world

    SciTech Connect

    Fridleifsson, I.B.

    1998-12-01

    Geothermal energy has been produced commercially for nearly a century, and on the scale of hundreds of MW for over four decades both for electricity generation and direct use. The world direct-use energy production is about 37 TWh/a (installed capacity of 10,000 MWt in nearly forty countries), and is, with the exception of China, mainly in the industrialized, and central and eastern European countries. Fourteen countries have installed capacities over 100 MWt. The main uses are space heating (33%), heat pumps (12%) for heating and cooling, bathing (19%), greenhouses (14%), aquaculture (11%) and industry (10%). The application of the ground-source heat pump opens a new dimension in the scope for using the earth`s heat, as heat pumps can be used basically everywhere and are not site specific as conventional geothermal resources. Geothermal energy, with its proven technology and abundant resources, can make a very significant contribution towards reducing the emission of greenhouse gases worldwide. It is necessary, however, that governments implement a legal and institutional framework and fiscal instruments allowing geothermal resources to compete with conventional energy systems and securing economic support in consideration of the significant environmental benefits of this energy source.

  7. Seismic response to fluid injection at the Salton Sea geothermal field

    NASA Astrophysics Data System (ADS)

    Lajoie, L. J.; Brodsky, E. E.

    2012-12-01

    California hosts both the largest geothermal resource capacity and highest seismicity rate in the nation. With plans to increase geothermal output, and proven earthquake triggering in the vicinity of geothermal power plants worldwide, it is important to determine the local and regional effects of geothermal power production. This study examines the link between fluid injection and seismicity at the Salton Sea geothermal field in southern California by attempting to answer three motivating questions: 1) Does fluid injection at the geothermal field change local seismicity in a measurable way? 2) Are aftershocks triggered at the same rate inside and outside of the field? 3) How do the triggered aftershocks interact with regional fault networks, specifically, could these aftershocks trigger a societally significant event on the southern San Andreas fault? We use monthly fluid injection and production data from 1980 to 2012 for 88 wells at the Salton Sea geothermal field and seismic data for the same time span from the relocated Hauksson, Yang, and Shearer earthquake catalog for southern California to evaluate these issues. We find that seismicity is correlated in both time and space in the Salton Sea geothermal field to injection. The observations strongly suggest triggering in the field. We also find that earthquakes within the field trigger aftershocks at a higher rate than most earthquakes elsewhere in California. The combination of observations suggest that aftershocks from induced seismicity could extend beyond the edges of the field into the neighboring tectonic system.

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

    SciTech Connect

    Garg, S.K.; Pritchett, J.W.; Stevens, J.L.; Luu, L.; Combs, J.

    1996-11-01

    The principal purpose of this case study of the Sumikawa Geothermal Field is to document and to evaluate the use of drilling logs, surface and downhole geophysical measurements, chemical analyses, and pressure transient data for the assessment of a high temperature volcanic geothermal field. The work accomplished during Year 1 of this ongoing program is described in the present report. A brief overview of the Sumikawa Geothermal Field is given. The drilling information and downhole pressure, temperature, and spinner surveys are used to determine feedzone locations, pressures and temperatures. Available injection and production data from both slim holes and large-diameter wells are analyzed to evaluate injectivity/productivity indices and to investigate the variation of discharge rate with borehole diameter. Finally, plans for future work are outlined.

  9. Thermal conditions for geothermal energy exploitation in the Transcarpathian depression and surrounding units

    NASA Astrophysics Data System (ADS)

    Majcin, Dušan; Kutas, Roman; Bilčík, Dušan; Bezák, Vladimír; Korchagin, Ignat

    2016-03-01

    The contribution presents the results acquired both by direct cognitive geothermic methods and by modelling approaches of the lithosphere thermal state in the region of the Transcarpathian depression and surrounding units. The activities were aimed at the determination of the temperature field distribution and heat flow density distribution in the upper parts of the Earth's crust within the studied area. Primary new terrestrial heat flow density map was constructed from values determined for boreholes, from their interpretations and from newest outcomes of geothermal modelling methods based on steady-state and transient approaches, and also from other recently gained geophysical and geological knowledge. Thereafter we constructed the maps of temperature field distribution for selected depth levels of up to 5000 m below the surface. For the construction we have used measured borehole temperature data, the interpolation and extrapolation methods, and the modelling results of the refraction effects and of the influences of source type anomalies. New maps and other geothermic data served for the determination of depths with rock temperatures suitable for energy utilization namely production of electric energy minimally by the binary cycles. Consequently the thermal conditions were used to identify the most perspective areas for geothermal energy exploitation in the region under study.

  10. Daemen Alternative Energy/Geothermal Technologies Demonstration Program Erie County

    SciTech Connect

    Beiswanger, Jr, Robert C

    2010-05-20

    The purpose of the Daemen Alternative Energy/Geothermal Technologies Demonstration Project is to demonstrate the use of geothermal technology as model for energy and environmental efficiency in heating and cooling older, highly inefficient buildings. The former Marian Library building at Daemen College is a 19,000 square foot building located in the center of campus. Through this project, the building was equipped with geothermal technology and results were disseminated. Gold LEED certification for the building was awarded. 1) How the research adds to the understanding of the area investigated. This project is primarily a demonstration project. Information about the installation is available to other companies, organizations, and higher education institutions that may be interested in using geothermal energy for heating and cooling older buildings. 2) The technical effectiveness and economic feasibility of the methods or techniques investigated or demonstrated. According to the modeling and estimates through Stantec, the energy-efficiency cost savings is estimated at 20%, or $24,000 per year. Over 20 years this represents $480,000 in unrestricted revenue available for College operations. See attached technical assistance report. 3) How the project is otherwise of benefit to the public. The Daemen College Geothermal Technologies Ground Source Heat Pumps project sets a standard for retrofitting older, highly inefficient, energy wasting and environmentally irresponsible buildings quite typical of many of the buildings on the campuses of regional colleges and universities. As a model, the project serves as an energy-efficient system with significant environmental advantages. Information about the energy-efficiency measures is available to other colleges and universities, organizations and companies, students, and other interested parties. The installation and renovation provided employment for 120 individuals during the award period. Through the new Center, Daemen will

  11. IRETHERM: The geothermal energy potential of Irish radiothermal granites

    NASA Astrophysics Data System (ADS)

    Farrell, Thomas; Jones, Alan; Muller, Mark; Feely, Martin; Brock, Andrew; Long, Mike; Waters, Tim

    2014-05-01

    The IRETHERM project is developing a strategic understanding of Ireland's deep geothermal energy potential through integrated modelling of new and existing geophysical and geological data. One aspect of IRETHERM's research focuses on Ireland's radiothermal granites, where increased concentrations of radioelements provide elevated heat-production (HP), surface heat-flow (SHF) and subsurface temperatures. An understanding of the contribution of granites to the thermal field of Ireland is important to assessing the geothermal energy potential of this low-enthalpy setting. This study focuses on the Galway granite in western Ireland, and the Leinster and the buried Kentstown granites in eastern Ireland. Shallow (<250 m) boreholes were drilled into the exposed Caledonian Leinster and Galway granites as part of a 1980's geothermal project. These studies yielded HP = 2-3 μWm-3 and HF = 80 mWm-2 at the Sally Gap borehole in the Northern Units of the Leinster granite, to the SW of Dublin. In the Galway granite batholith, on the west coast of Ireland, the Costelloe-Murvey granite returned HP = 7 μWm-3 and HF = 77 mWm-2, measured at the Rossaveal borehole. The buried Kentstown granite, 35 km NW of Dublin, has an associated negative Bouguer anomaly and was intersected by two mineral exploration boreholes at depths of 660 m and 490 m. Heat production is measured at 2.4 μWm-3 in core samples taken from the weathered top 30 m of the granite. The core of this study consists of a program of magnetotelluric (MT) and audio-magnetotelluric (AMT) data acquisition across the three granite bodies, over three fieldwork seasons. MT and AMT data were collected at 59 locations along two profiles over the Leinster granite. Preliminary results show that the northern units of the Leinster granite (40 km SW of Dublin) extend to depths of 2-5 km. Preliminary results from the southern profile suggest a greater thickness of granite to a depth of 6-9 km beneath the Tullow pluton, 75 km SW of

  12. Geothermal development: energy security in a volatile marketplace

    SciTech Connect

    Otte, C.

    1986-07-01

    Historically, the energy industry has been beset by volatile prices and uncertain supplies. The authors are living through a short-term glut and facing a long-term shortage. With oil prices dropping dramatically, countries will again rely on imported oil. However, prices and demand will inevitably rise, and they will once more be dependent on foreign sources. The present worldwide energy industry slump has had a negative effect on the rate of geothermal development. Individual governments should take advantage of low crude prices to plan and explore for alternative sources of energy. A stable, long term energy policy will ensure the development of all of a country's energy resources, using each to its best advantage: natural gas for domestic needs and chemical raw material; coal for large-scale process heat application; and coal, nuclear, and geothermal energy as sources for central power generation.

  13. Geochemical evidence of drawdown in the Cerro Prieto geothermal field

    USGS Publications Warehouse

    Truesdell, A.H.; Manon, M.A.; Jimenez, S.M.E.; Sanchez, A.A.; Fausto, L.J.J.

    1979-01-01

    Some wells of the Cerro Prieto geothermal field have undergone changes in the chemistry of fluids produced which reflect reservoir processes. Pressure decreases due to production in the southeastern part of the field have produced both drawdown of lower chloride fluids from an overlying aquifer and boiling in the aquifer with excess steam reaching the wells. These reservoir changes are indicated by changes in fluid chloride concentrations, Na/K ratios and measured enthalpies and by comparisons of aquifer fluid temperatures and chloride concentrations calculated from enthalpy and chemical measurements. Fluid temperatures have not been greatly affected by this drawdown because heat contained in the rock was transferred to the fluid. When this heat is exhausted, fluid temperatures may drop rapidly. ?? 1979.

  14. Durability of various cements in a well of the Cerro Prieto geothermal field

    SciTech Connect

    Krause, Ralph F., Jr.; Kukacka, Larry E.

    1982-10-08

    The durability of each of 16 different cements was evaluated by both room temperature compressive strength and water permeability measurements, following various periods of treatment of the cements in flowing geothermal fluid of the Cerro Prieto field of Mexico. Some of these cements were selected through a Department of Energy program to develop improved cements for geothermal well completion while the others were contributed by several other institutions interested in the tests. Two types of specimens of the cements were used in the tests: (a) 50 mm cubes which were precured 1 da in molds under water in an autoclave at 200 C and 20 MPa and (b) cement slurries which were prepared and cast in sandstone cups at the field. Federal de Electricidad a set of both types of specimens was installed in baskets which were placed 700 m downhole a well at 214 C, and an identical set of specimens was installed in special aboveground vessels near the wellhead. Following periods of 1 da. 3 mo, 6 mo. and 12 mo, specimens were withdrawn from the geothermal treatment and divided evenly between the Instituto de Investigaciones Electricas and the National Bureau of Standards for property measurements. This paper gives the downhole results by the latter laboratory. Final values will be published when the results of both laboratories are collated and reviewed.

  15. Two-phase flow measurement by chemical tracer technique for Uenotai geothermal field in Japan

    SciTech Connect

    Sato, Tatsuya; Osato, Kazumi; Hirtz, P.

    1996-12-31

    A tracer flow-test (TFT) survey of three production wells was performed in February, 1996, for Akita Geothermal Energy Co., Ltd. (AGECO) at the Uenotai geothermal field in the Akita prefecture of northern Honshu, Japan. The survey was conducted as a demonstration test of the chemical tracer method for two-phase flow measurement. Although the tracer method has been in commercial use for about 4 years this was the first time the technique had been applied on wells with mixing runs of less than 12 meters. The tracers were injected through the wing valve on the side of the wellheads to maximize the tracer dispersion through the 9 meters of pipeline available before sample collection. The three wells tested had steam fractions at the wellhead of 38 to 99.4 % by weight and total flow rates of 31.5 to 51.5 tons/hr. Based on the test results the chemical tracer method is considered accurate under the conditions experienced at the Uenotai geothermal field and has been adopted for routine flow rate and enthalpy monitoring.

  16. Geothermal Energy: Resource and Utilization. A Teaching Module.

    ERIC Educational Resources Information Center

    Nguyen, Van Thanh

    The search for new energy resources as alternatives to fossil fuels have generated new interest in the heat of the earth itself. New geothermal areas with a variety of characteristics are being explored, as are new ways of extracting work from naturally heated steam and hot water. Some of this effort is discussed in this three-part module. Five…

  17. GIS Regional Spatial Data from the Great Basin Center for Geothermal Energy: Geochemical, Geodesic, Geologic, Geophysical, Geothermal, and Groundwater Data

    DOE Data Explorer

    The Great Basin Center for Geothermal Energy, part of the University of Nevada, Reno, conducts research towards the establishment of geothermal energy as an economically viable energy source within the Great Basin. The Center specializes in collecting and synthesizing geologic, geochemical, geodetic, geophysical, and tectonic data, and using Geographic Information System (GIS) technology to view and analyze this data and to produce favorability maps of geothermal potential. The center also makes its collections of spatial data available for direct download to the public. Data are in Lambert Conformable Conic Projection.

  18. 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.

  19. Modeling discharge requirements for deep geothermal wells at the Cerro Prieto geothermal field, MX

    SciTech Connect

    Menzies, Anthony J.; Granados, Eduardo E.; Puente, Hector Gutierrez; Pierres, Luis Ortega

    1995-01-26

    During the mid-l980's, Comision Federal de Electricidad (CFE) drilled a number of deep wells (M-200 series) at the Cerro Prieto geothermal field, Baja California, Mexico to investigate the continuation of the geothermal reservoir to the east of the Cerro Prieto-II and III production areas. The wells encountered permeability at depths ranging from 2,800 to 4,400 m but due to the reservoir depth and the relatively cold temperatures encountered in the upper 1,000 to 2,000 m of the wells, it was not possible to discharge some of the wells. The wells at Cerro Prieto are generally discharged by injecting compressed air below the water level using 2-3/8-inch tubing installed with either a crane or workover rig. The objective of this technique is to lift sufficient water out of the well to stimulate flow from the reservoir into the wellbore. However, in the case of the M-200 series wells, the temperatures in the upper 1,000 to 2,000 m are generally below 50 C and the heat loss to the formation is therefore significant. The impact of heat loss on the stimulation process was evaluated using both a numerical model of the reservoir/wellbore system and steady-state wellbore modeling. The results from the study indicate that if a flow rate of at least 300 liters/minute can be sustained, the well can probably be successfully stimulated. This is consistent with the flow rates obtained during the successful stimulations of wells M-202 and M-203. If the flow rate is closer to 60 liters/minute, the heat loss is significant and it is unlikely that the well can be successfully discharged. These results are consistent with the unsuccessful discharge attempts in wells M-201 and M-205.

  20. Geothermal field development in foreland basins: Case study Mauerstetten, Bavarian Molasse Basin (Germany)

    NASA Astrophysics Data System (ADS)

    Moeck, Inga; Jensch, Anna; Steiger, Thorsten; Stiller, Manfred; Tondera, Detlef; Blöcher, Guido

    2013-04-01

    Foreland basins with their increasing depth towards the orogenic front are ideal geologic systems for geothermal resources. The Bavarian Molasse Basin is an example where geothermal energy is being successfully developed mainly by industry. However, the predicted productivity is not achieved in all project sites because either temperature or flow rate or both are lower than expected. The case study Mauerstetten in the southwestern Bavarian Molasse Basin is one of the industry triggered projects where high temperature of over 150°C but insufficient flow rate dragged the overall project performance down. As research project, Mauerstetten is revived aiming to gain the relevant knowledge to develop a strategy to increase reservoir productivity. Within this framework structural geological and biostratigraphical analysis were combined with geomechanical tests. The structural geological analysis on 2D seismic sections revealed fossil normal faults in a strike slip to transpressional stress regime. Biostratigraphical analysis was undertaken on thin sections from wellbore cuttings to delineate appropriate analog outcrops for geomechanical tests to predict reservoir behavior under injection and production. Remarkably, the upper Jurassic Malm formation exhibits extremely high rock strength if Tubiphytes dominate the carbonate rock. Tubiphytes are encrusting and branching organisms associated with shallow-water sponge reefs rimmed along the continental margin of Laurasia towards the Tethys during Upper Jurassic. Other than coral dominated reef limestone, Tubiphyte-dominated limestone is expected to trigger a high self-propping effect along shear fractures due to its brittleness, and a low reactivation potential due to its high rock strength. Natural and artificial shear fractures are expected to be preferential flow pathways. Abnormal high injection pressure is necessary to induce slip in Tubiphytes limestone in the present-day stress field. Our study exemplifies that

  1. Combining total energy and energy industrial center concepts to increase utilization efficiency of geothermal energy

    NASA Technical Reports Server (NTRS)

    Bayliss, B. P.

    1974-01-01

    Integrating energy production and energy consumption to produce a total energy system within an energy industrial center which would result in more power production from a given energy source and less pollution of the environment is discussed. Strong governmental support would be required for the crash drilling program necessary to implement these concepts. Cooperation among the federal agencies, power producers, and private industry would be essential in avoiding redundant and fruitless projects, and in exploiting most efficiently our geothermal resources.

  2. Geophysical surveys in Parvati valley geothermal field, Kullu, India

    NASA Astrophysics Data System (ADS)

    Rakesh Kumar, S. B.; Singh, Mohan; Gupta, L.; Rao, G. V.

    1982-08-01

    Direct current resistivity surveys and shallow temperature measurements were carried out for geothermal exploration in a part of Parvati valley, goethermal field, Himachal Pradesh, India. At a few places, the Schlumberger soundings pointed to the presence of a relatively low-resistivity shallow layer, which probably represents fractured and jointed quartzite, saturated with hot/cold water. Wenner resistivity profiles indicate the presence of some possible shallow subsurface lateral hot water channels across the valley at Manikaran. Shallow temperature measurements show a good subsurface thermal anomaly near the confluence of the rivers Brahmaganga and Parvati. The results of the survey, together with other available geodata, suggest that an anomalous heat source does not lie beneath the study area. It is postulated that the meteoric water, originating at high elevations after heating as a result of circulation at depth, emerges at the surface in the Parvati valley as hot springs, after mixing in various proportions with near surface cold waters.

  3. RAPID CASING CORROSION IN HIGH TEMPERATURE LIQUID DOMINATED GEOTHERMAL FIELDS

    SciTech Connect

    Bixley, P.F.; Wilson, D.M.

    1985-01-22

    Downhole logging and workover operations on 12-20 year old wells in several high temperature, liquid-dominated geothermal fields in New Zealand has shown that severe corrosion has commonly occurred in the production casing string where this is unprotected by larger diameter casings. To date corrosion products from only one well have been examined in detail. These indicate that corrosion attack commences at the outer casing wall and continues at a rate as great as 0.8mm/year. Rapid corrosion has been attributed to neutral or slightly acid high bicarbonate waters formed by the absorption of steam and gas into shallow aquifers not directly connected to the deeper, high chloride reservoir.

  4. Microearthquake Studies at the Salton Sea Geothermal Field

    DOE Data Explorer

    Templeton, Dennise

    2013-10-01

    The objective of this project is to detect and locate microearthquakes to aid in the characterization of reservoir fracture networks. Accurate identification and mapping of the large numbers of microearthquakes induced in EGS is one technique that provides diagnostic information when determining the location, orientation and length of underground crack systems for use in reservoir development and management applications. Conventional earthquake location techniques often are employed to locate microearthquakes. However, these techniques require labor-intensive picking of individual seismic phase onsets across a network of sensors. For this project we adapt the Matched Field Processing (MFP) technique to the elastic propagation problem in geothermal reservoirs to identify more and smaller events than traditional methods alone.

  5. Results of investigation at the Ahuachapan Geothermal Field, El Salvador

    SciTech Connect

    Fink, J.B. )

    1990-04-01

    The Ahuachapan Geothermal Field (AGF) is a 95 megawatt geothemal-sourced power-plant operated by the Comision Ejecutiva Hidroelectrica del Rio Lempa (CEL) of El Salvador. During the past decade, as part of an effort to increase in situ thermal reserves in order to realize the full generation capacity of the AGF, extensive surface geophysical coverage has been obtained over the AGF and the prospective Chipilapa area to the east. The geophysical surveys were performed to determine physical property characteristics of the known reservoir and then to search for similar characteristics in the Chipilapa area. A secondary objective was to evaluate the surface recharge area in the highlands to the south of the AGF. The principal surface electrical geophysical methods used during this period were DC resistivity and magnetotellurics. Three available data sets have been reinterpreted using drillhole control to help form geophysical models of the area. The geophysical models are compared with the geologic interpretations.

  6. Numerical simulation of the Mori geothermal field, JP

    SciTech Connect

    Yukihiro Sakagawa; Masahiro Takahashi; Mineyuki Hanano; Tsuneo Ishido; Nobuhiro Demboya

    1994-01-20

    A numerical study of the Mori geothermal field which consisted of a series of three-dimensional natural state modeling and history matching was carried out with porous models. Finally satisfactory fits both on temperature and pressure of the natural state and on pressure history caused by exploitation were obtained. The results indicate that the deep hot water ascends mainly through the fractures near the caldera wall and the fractures confined to some lithofaces, and some of the ascending hot water flows to the west from the caldera. A sketch of the geological structure, the way of making up the initial numerical model, the way of concluding free parameters, and results of calculations of natural state modeling and history matching for the best numerical model are presented.

  7. 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.

  8. Geothermal energy: clean power from the Earth's heat

    USGS Publications Warehouse

    Duffield, Wendell A.; Sass, John H.

    2003-01-01

    Societies in the 21st century require enormous amounts of energy to drive the machines of commerce and to sustain the lifestyles that many people have come to expect. Today, most of this energy is derived from oil, natural gas, and coal, supplemented by nuclear power. Local exceptions exist, but oil is by far the most common source of energy worldwide. Oil resources, however, are nonrenewable and concentrated in only a few places around the globe, creating uncertainty in long-term supply for many nations. At the time of the Middle East oil embargo of the 1970s, about a third of the United States oil supply was imported, mostly from that region. An interruption in the flow of this import disrupted nearly every citizen’s daily life, as well as the Nation’s economy. In response, the Federal Government launched substantial programs to accelerate development of means to increasingly harness “alternative energies”—primarily biomass, geothermal, solar, and wind. The new emphasis on simultaneously pursuing development of several sources of energy recognized the timeless wisdom found in the proverb of “not putting all eggs in one basket.” This book helps explain the role that geothermal resources can play in helping promote such diversity and in satisfying our Nation’s vast energy needs as we enter a new millennium. For centuries, people have enjoyed the benefits of geothermal energy available at hot springs, but it is only through technological advances made during the 20th century that we can tap this energy source in the subsurface and use it in a variety of ways, including the generation of electricity. Geothermal resources are simply exploitable concentrations of the Earth’s natural heat (thermal energy). The Earth is a bountiful source of thermal energy, continuously producing heat at depth, primarily by the decay of naturally occurring radioactive isotopes—principally of uranium, thorium, and potassium—that occur in small amounts in all rocks

  9. Geothermal Energy Development in the Eastern United States. Final Report

    SciTech Connect

    1981-10-01

    This document represents the final report from the Applied Physics Laboratory (APL) of The Johns Hopkins University on its efforts on behalf of the Division of Geothermal Energy (DGE) of the Department of Energy (DOE). For the past four years, the Laboratory has been fostering development of geothermal energy in the Eastern United States. While the definition of ''Eastern'' has changed somewhat from time to time, basically it means the area of the continental United States east of the Rocky Mountains, plus Puerto Rico but excluding the geopressured regions of Texas and Louisiana. During these years, the Laboratory developed a background in geology, hydrology, and reservoir analysis to aid it in establishing the marketability of geothermal energy in the east. Contrary to the situation in the western states, the geothermal resource in the east was clearly understood to be inferior in accessible temperature. On the other hand, there were known to be copious quantities of water in various aquifers to carry the heat energy to the surface. More important still, the east possesses a relatively dense population and numerous commercial and industrial enterprises, so that thermal energy, almost wherever found, would have a market. Thus, very early on it was clear that the primary use for geothermal energy in the east would be for process heat and space conditioning--heating and cool electrical production was out of the question. The task then shifted to finding users colocated with resources. This task met with modest success on the Atlantic Coastal Plain. A great deal of economic and demographic analysis pinpointed the prospective beneficiaries, and an intensive ''outreach'' campaign was mounted to persuade the potential users to invest in geothermal energy. The major handicaps were: (1) The lack of demonstrated hydrothermal resources with known temperatures and expected longevity; and (2) The lack of a ''bellwether'' installation for entrepreneurs to see, touch, and

  10. Small-Scale Geothermal Power Plant Field Verification Projects: Preprint

    SciTech Connect

    Kutscher, C.

    2001-07-03

    In the spring of 2000, the National Renewable Energy Laboratory issued a Request for Proposal for the construction of small-scale (300 kilowatt [kW] to 1 megawatt [MW]) geothermal power plants in the western United States. Five projects were selected for funding. Of these five, subcontracts have been completed for three, and preliminary design work is being conducted. The three projects currently under contract represent a variety of concepts and locations: a 1-MW evaporatively enhanced, air-cooled binary-cycle plant in Nevada; a 1-MW water-cooled Kalina-cycle plant in New Mexico; and a 750-kW low-temperature flash plant in Utah. All three also incorporate direct heating: onion dehydration, heating for a fish hatchery, and greenhouse heating, respectively. These projects are expected to begin operation between April 2002 and September 2003. In each case, detailed data on performance and costs will be taken over a 3-year period.

  11. Deep Geothermal Energy for Lower Saxony (North Germany) - Combined Investigations of Geothermal Reservoir Characteristics

    NASA Astrophysics Data System (ADS)

    Hahne, Barbara; Thomas, Rüdiger

    2014-05-01

    In Germany, successful deep geothermal projects are mainly situated in Southern Germany in the Molassebecken, furthermore in the Upper Rhine Graben and, to a minor extend, in the North German Basin. Mostly they are hydrothermal projects with the aim of heat production. In a few cases, they are also constructed for the generation of electricity. In the North German Basin temperature gradients are moderate. Therefore, deep drilling of several thousand meters is necessary to reach temperatures high enough for electricity production. However, the porosity of the sedimentary rocks is not sufficient for hydrothermal projects, so that natural fracture zones have to be used or the rocks must be hydraulically stimulated. In order to make deep geothermal projects in Lower Saxony (Northern Germany) economically more attractive, the interdisciplinary research program "Geothermal Energy and High-Performance Drilling" (gebo) was initiated in 2009. It comprises four focus areas: Geosystem, Drilling Technology, Materials and Technical System and aims at improving exploration of the geothermal reservoir, reducing costs of drilling and optimizing exploitation. Here we want to give an overview of results of the focus area "Geosystem" which investigates geological, geophysical, geochemical and modeling aspects of the geothermal reservoir. Geological and rock mechanical investigations in quarrys and core samples give a comprehensive overview on rock properties and fracture zone characteristics in sandstones and carbonates. We also show that it is possible to transfer results of rock property measurements from quarry samples to core samples or to in situ conditions by use of empirical relations. Geophysical prospecting methods were tested near the surface in a North German Graben system. We aim at transferring the results to the prospection of deep situated fracture zones. The comparison of P- and S-wave measurements shows that we can get hints on a possible fluid content of the

  12. A reservoir engineering assessment of the San Jacinto-Tizate Geothermal Field, Nicaragua

    SciTech Connect

    Ostapenko, S.; Spektor, S.; Davila, H.; Porras, E.; Perez, M.

    1996-01-24

    More than twenty yews have passed since geothermal research and drilling took place at the geothermal fields in Nicaragua- Tbe well horn Momotombo Geothermal Field (70 We) has been generating electricity since 1983, and now a new geothermal field is under exploration. the San Jacinto-Tizate. Two reservoirs hydraulic connected were found. The shallow reservoir (270°C) at the depth of 550 - 1200 meters, and the deep one at > 1600 meters. Both of theme are water dominated reservoirs, although a two phase condition exist in the upper part of the shallow one. Different transient tests and a multi-well interference test have been carried out, very high transmissivity value were estimated around the well SJ-4 and average values for the others. A preliminar conceptual model of the geothermal system is given in this paper, as the result of the geology, geophysics, hydrology studies, drilling and reservoir evaluation.

  13. The Ahuachapan geothermal field, El Salvador: Reservoir analysis

    SciTech Connect

    Aunzo, Z.; Bodvarsson, G.S.; Laky, C.; Lippmann, M.J.; Steingrimsson, B.; Truesdell, A.H.; Witherspoon, P.A.; Icelandic National Energy Authority, Reykjavik; Geological Survey, Menlo Park, CA; Lawrence Berkeley Lab., CA )

    1989-08-01

    The Earth Sciences Division of Lawrence Berkeley Laboratory (LBL) is conducting a reservoir evaluation study of the Ahuachapan geothermal field in El Salvador. This work is being performed in cooperation with the Comision Ejecutiva Hidroelectrica del Rio Lempa (CEL) and the Los Alamos National Laboratory (LANL). This report describes the work done during the first year of the study (FY 1988--89), and includes the (1) development of geological and conceptual models of the field, (2) evaluation of the initial thermodynamic and chemical conditions and their changes during exploitation, (3) evaluation of interference test data and the observed reservoir pressure decline, and (4) the development of a natural state model for the field. The geological model of the field indicates that there are seven (7) major and five (5) minor faults that control the fluid movement in the Ahuachapan area. Some of the faults act as a barrier to flow as indicated by large temperature declines towards the north and west. Other faults act as preferential pathways to flow. The Ahuachapan Andesites provide good horizontal permeability to flow and provide most of the fluids to the wells. The underlying Older Agglomerates also contribute to well production, but considerably less than the Andesites. 84 refs.

  14. Absence of Remote Triggering in Geothermal Fields Due to Human Activity

    NASA Astrophysics Data System (ADS)

    Ge, S.; Zhang, Q.; Lin, G.

    2014-12-01

    Operational geothermal fields typically have high seismicity rates, which could be caused by both tectonic and anthropogenic activities. Due to the high background seismicity and possible interaction between fluid and seismic waves, geothermal areas have been recognized to be susceptible to large remote earthquakes. However, whether human activity (geothermal production) affects remote earthquake triggering by changing the stress state is unclear. Here we choose two geothermal fields, Coso and Salton Sea in southern California, to study the spatiotemporal distributions of the triggered earthquakes following the 1992 Mw 7.3 Landers and 1999 Mw 7.1 Hector Mine earthquakes. These two geothermal fields have been in operation since 1980s with comparable net capacity, and have long-term geothermal fluid loss. By analyzing the regional catalog recorded by the Southern California Seismic Network, we find that these two operational geothermal areas remain unaffected by the remote mainshocks, whereas the surrounding areas show vigorous triggered responses. We interpret this phenomenon as a result of human activity, which presumably has brought the stress state away from failure by reducing pore pressure. To further understand how much the human activity can affect the stress state, we also conduct a systematic study on Long Valley Caldera in northern California as a comparison site. Long Valley Caldera hosts an active geothermal field with net capacity about one sixth of that in Coso or Salton Sea geothermal field, and the extraction volume is not constantly larger than the injection. We will show comparisons of the triggered response in Long Valley with the two geothermal fields in southern California.

  15. Southwest Alaska Regional Geothermal Energy Project

    SciTech Connect

    Holdmann, Gwen

    2015-04-30

    The village of Elim, Alaska is 96 miles west of Nome, on the Seward Peninsula. The Darby Mountains north of the village are rich with hydrothermal systems associated with the Darby granitic pluton(s). In addition to the hot springs that have been recorded and studied over the last 100 years, additional hot springs exist. They are known through a rich oral history of the region, though they are not labeled on geothermal maps. This research primarily focused on Kwiniuk Hot Springs, Clear Creek Hot Springs and Molly’s Hot Springs. The highest recorded surface temperatures of these resources exist at Clear Creek Hot Springs (67°C). Repeated water sampling of the resources shows that maximum temperatures at all of the systems are below boiling.

  16. 3D Extended Logging for Geothermal Resources: Field Trials with the Geo-Bilt System

    SciTech Connect

    Mallan, R; Wilt, M; Kirkendall, B; Kasameyer, P

    2002-05-29

    Geo-BILT (Geothermal Borehole Induction Logging Tool) is an extended induction logging tool designed for 3D resistivity imaging around a single borehole. The tool was developed for deployment in high temperature geothermal wells under a joint program funded by the California Energy Commission, Electromagnetic Instruments (EMI) and the U.S. Department of Energy. EM1 was responsible for tool design and manufacture, and numerical modeling efforts were being addressed at Lawrence Livermore Laboratory (LLNL) and other contractors. The field deployment was done by EM1 and LLNL. The tool operates at frequencies from 2 to 42 kHz, and its design features a series of three-component magnetic sensors offset at 2 and 5 meters from a three-component magnetic source. The combined package makes it possible to do 3D resistivity imaging, deep into the formation, from a single well. The manufacture and testing of the tool was completed in spring of 2001, and the initial deployment of Geo-BILT occurred in May 2001 at the Lost Hills oil field in southern California at leases operated by Chevron USA. This site was chosen for the initial field test because of the favorable geological conditions and the availability of a number of wells suitable for tool deployment. The second deployment occurred in April 2002 at the Dixie Valley geothermal field, operated by Caithness Power LLC, in central Nevada. This constituted the first test in a high temperature environment. The Chevron site features a fiberglass-cased observation well in the vicinity of a water injector. The injected water, which is used for pressure maintenance and for secondary sweep of the heavy oil formation, has a much lower resistivity than the oil bearing formation. This, in addition to the non-uniform flow of this water, creates a 3D resistivity structure, which is analogous to conditions produced from flowing fractures adjacent to geothermal boreholes. Therefore, it is an excellent site for testing the 3D capability of

  17. Geothermal Field Case Studies that Document the Usefulness of Models in Predicting Reservoir and Well Behavior

    SciTech Connect

    Lippmann, Marcelo J.

    1989-03-21

    The geothermal industry has shown significant interest in case histories that document field production histories and demonstrate the techniques which work best in the characterization and evaluation of geothermal systems. In response to this interest, LBL has devoted a significant part of its geothermal program to the compilation and analysis of data from US and foreign fields (e.g., East Mesa, The Geysers, Susanville, and Long Valley in California; Klamath Fall in Oregon; Valles Caldera, New Mexico; Cerro Prieto and Los Azufres in Mexico; Krafla and Nesjavellir in Iceland; Larderello in Italy; Olkaria in Kenya). In each of these case studies we have been able to test and validate in the field, or against field data, the methodology and instrumentation developed under the Reservoir Technology Task of the DOE Geothermal Program, and to add to the understanding of the characteristics and processes occurring in geothermal reservoirs. Case study results of the producing Cerro Prieto and Olkaria geothermal fields are discussed in this paper. These examples were chosen because they illustrate the value of conceptual and numerical models to predict changes in reservoir conditions, reservoir processes, and well performance that accompany field exploitation, as well as to reduce the costs associated with the development and exploitation of geothermal resources.

  18. Geothermal field case studies that document the usefulness of models in predicting reservoir and well behavior

    SciTech Connect

    Lippmann, M.J.

    1989-03-01

    The geothermal industry has shown significant interest in case histories that document field production histories and demonstrate the techniques which work best in the characterization and evaluation of geothermal systems. In response to this interest, LBL has devoted a significant art of its geothermal program to the compilation and analysis of data from US and foreign fields (e.g., East Mesa, The Geysers, Susanville, and Long Valley in California; Klamath Falls in Oregon; Valles Caldera, New Mexico; Cerro Prieto and Los Azufres in Mexico; Krafla and Nesjavellir in Iceland; Larderello in Italy; Olkaria in Kenya). In each of these case studies we have been able to test and validate in the field, or against field data, the methodology and instrumentation developed under the Reservoir Technology Task of the DOE Geothermal Program, and to add to the understanding of the characteristics and processes occurring in geothermal reservoirs. Case study results of the producing Cerro Prieto and Olkaria geothermal fields are discussed in this paper. These examples were chosen because they illustrate the value of conceptual and numerical models to predict changes in reservoir conditions, reservoir processes, and well performance that accompany field exploitation, as well as to reduce the costs associated with the development and exploitation of geothermal resources. 14 refs., 6 figs.

  19. Reservoir analysis of the Palinpinon geothermal field, Negros Oriental, Philippines

    SciTech Connect

    Amistoso, A.E.; Aquino, B.G.; Aunzo, Z.P.; Jordan, O.T.; Ana, F.X.M.S.; Bodvarsson, G.S.; Doughty, C.

    1993-10-01

    The Philippine National Oil Company and Lawrence Berkeley Laboratory have conducted an informal cooperative project on the reservoir evaluation of the Palinpinon geothermal field in the Philippines. The work involved the development of various numerical models of the field in order to understand the observed data. A three-dimensional porous medium model of the reservoir has been developed that matches well the observed pressure declines and enthalpy transients of the wells. Submodels representing the reservoir as a fractured porous medium were developed for the analysis of chemical transport of chlorides within the reservoir and the movement of the cold water front away from injection wells. These models indicate that the effective porosity of the reservoir varies between 1 and 7% and the effective permeability between 1 and 45 millidarcies. The numerical models were used to predict the future performance of the Palinpinon reservoir using various possible exploitation scenarios. A limited number of make-up wells were allocated to each sector of the field. When all the make-up wells had been put on line, power production gradually began to decline. The model indicates that under the assumed conditions it will not be possible to maintain the planned power production of 112.5 MWe at Palinpinon I and 80 MWe at Palinpinon II for the next 30 years, but the decline in power output will be within acceptable normal operating capacities of the plants.

  20. Seismostatistical characterization of microseismicity observed at geothermal fields

    NASA Astrophysics Data System (ADS)

    Eto, T.; Asanuma, H.; Adachi, M.; Saeki, K.; Aoyama, K.; Ozeki, H.; Häring, M. O.

    2012-12-01

    Recently, occurrence of felt earthquakes has been recognized as one of the most critical environmental burdens associated with geothermal development. We have taken seismostatistical approach to evaluate characteristics of the microseismicity at geothermal fields to establish realtime and automated monitoring techniques of the reservoir changes and risk assessment of the felt earthquakes. In this study, we have introduced the Epidemic Type Aftershock Sequence (ETAS) model (Ogata, JASA, 1988) to statistically model the time series of occurrences and the magnitude of microseismic events from hydrothermal and EGS fields. Here maximum likelihood estimation has been employed to estimate optimum parameters of the ETAS model. We analyzed microseismic events observed at Yanaizu Nishiyama, one of the largest hydrothermal fields in Japan. In this field, four felt earthquakes with local magnitude larger than 3.0 occurred during production operation since 1996, although no clear correlation between the occurrence of the felt earthquakes and operation to the reservoir has been observed (Asanuma et al., Trans. GRC, 2011). We found that the occurrence rate of primary fluid signals, which are the events triggered by external forcing and have been interpreted to be independent from a series of aftershocks (Hainzl and Ogata, JGR, 2005), correlated to the reinjection rate (Fig. 1). However, no significant change in the other parameters in the ETAS model has been observed. We also analyzed microseismic events observed at Basel EGS site in Switzerland, where some felt earthquakes occurred during and after hydraulic stimulation. The estimated ETAS model demonstrated that there is a correlation between the occurrence rate of primary fluid signals and injection rate. We, however, found that there is limitation to fit the ETAS model to the induced seismic events and new seismostatistical model is required for microseismic reservoir monitoring.ig. 1 A relation among production

  1. Geothermal energy: opportunities for California commerce. Phase I report

    SciTech Connect

    Longyear, A.B.

    1981-12-01

    The potential geothermal direct-use energy market and its application to projects in California are assessed. Project identification effort is to be focused on those that have the highest probability for near-term successful commercial operations. Near-term herein means 2 to 5 years for project implementation. Phase I has been focused on defining and assessing: (1) the geothermal direct-use resources that are suitable for near-term utilization; and (2) the generic applications (municipal heating districts, horticultural greenhouse firms, laundries, etc.) that are suitable for near-term projects. Five economic development regions in the state, containing recognized geothermal direct-use resources, have been defined. Thirty-eight direct use resources have been evaluated in these regions. After assessment against pre-selected criteria, twenty-seven have been rated with a priority of I, II or III, thereby qualifying them for further marketing effort. The five areas with a priority of I are summarized. These areas have no perceived impediments to near-term development. Twenty-nine generic categories of applications were assessed against previously selected criteria to determine their near term potential for direct use of geothermal fluids. Some twenty industry, commercial and institutional application categories were rated with a priority of I, II or III and warrant further marketing efforts. The seven categories with a priority of I are listed. These categories were found to have the least impediments to near-term application projects.

  2. 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.

  3. A comparison of long-term changes in seismicity at The Geysers, Salton Sea, and Coso geothermal fields

    NASA Astrophysics Data System (ADS)

    Trugman, Daniel T.; Shearer, Peter M.; Borsa, Adrian A.; Fialko, Yuri

    2016-01-01

    Geothermal energy is an important source of renewable energy, yet its production is known to induce seismicity. Here we analyze seismicity at the three largest geothermal fields in California: The Geysers, Salton Sea, and Coso. We focus on resolving the temporal evolution of seismicity rates, which provides important observational constraints on how geothermal fields respond to natural and anthropogenic loading. We develop an iterative, regularized inversion procedure to partition the observed seismicity rate into two components: (1) the interaction rate due to earthquake-earthquake triggering and (2) the smoothly varying background rate controlled by other time-dependent stresses, including anthropogenic forcing. We apply our methodology to compare long-term changes in seismicity to monthly records of fluid injection and withdrawal. At The Geysers, we find that the background seismicity rate is highly correlated with fluid injection, with the mean rate increasing by approximately 50% and exhibiting strong seasonal fluctuations following construction of the Santa Rosa pipeline in 2003. In contrast, at both Salton Sea and Coso, the background seismicity rate has remained relatively stable since 1990, though both experience short-term rate fluctuations that are not obviously modulated by geothermal plant operation. We also observe significant temporal variations in Gutenberg-Richter b value, earthquake magnitude distribution, and earthquake depth distribution, providing further evidence for the dynamic evolution of stresses within these fields. The differing field-wide responses to fluid injection and withdrawal may reflect differences in in situ reservoir conditions and local tectonics, suggesting that a complex interplay of natural and anthropogenic stressing controls seismicity within California's geothermal fields.

  4. Gas chemistry and thermometry of the Cerro Prieto geothermal field

    SciTech Connect

    Nehring, N.L.; D'Amore, F.

    1981-01-01

    Geothermal gases at Cerro Prieto are derived from high temperature reactions within the reservoir or are introduced with recharge water. Gases collected from geothermal wells should, therefore, reflect reservoir conditions. Interpretation of gas compositions of wells indicates reservoir temperatures, controls of oxygen and sulfur fugacities, and recharge source and direction.

  5. 3D Magnetotelluic characterization of the Coso GeothermalField

    SciTech Connect

    Newman, Gregory A.; Hoversten, G. Michael; Wannamaker, Philip E.; Gasperikova, Erika

    2007-04-23

    Electrical resistivity may contribute to progress inunderstanding geothermal systems by imaging the geometry, bounds andcontrolling structures in existing production, and thereby perhapssuggesting new areas for field expansion. To these ends, a dense grid ofmagnetotelluric (MT) stations plus a single line of contiguous bipolearray profiling has been acquired over the east flank of the Cosogeothermal system. Acquiring good quality MT data in producing geothermalsystems is a challenge due to production related electromagnetic (EM)noise and, in the case of Coso, due to proximity of a regional DCintertie power transmission line. To achieve good results, a remotereference completely outside the influence of the dominant source of EMnoise must be established. Experimental results so far indicate thatemplacing a reference site in Amargosa Valley, NV, 65 miles from the DCintertie, isstill insufficient for noise cancellation much of the time.Even though the DC line EM fields are planar at this distance, theyremain coherent with the nonplanar fields in the Coso area hence remotereferencing produces incorrect responses. We have successfully unwrappedand applied MT times series from the permanent observatory at Parkfield,CA, and these appear adequate to suppress the interference of thecultural EM noise. The efficacy of this observatory is confirmed bycomparison to stations taken using an ultra-distant reference site eastof Socorro, NM. Operation of the latter reference was successful by usingfast ftp internet communication between Coso Junction and the New MexicoInstitute of Mining and Technology, using the University of Utah site asintermediary, and allowed referencing within a few hours of datadownloading at Coso. A grid of 102 MT stations was acquired over the Cosogeothermal area in 2003 and an additional 23 stations were acquired toaugment coverage in the southern flank of the first survey area in 2005.These data have been inverted to a fully three

  6. Preliminary plan for the development of geothermal energy in the town of Hawthorne, Nevada

    SciTech Connect

    Not Available

    1981-11-04

    Site characteristics pertinent to the geothermal development are described, including: physiography, demography, economy, and goals and objectives of the citizens as they relate to geothermal development. The geothermal reservoir is characterized on the basis of available information. The probable drilling depth to the reservoir, anticipated water production rates, water quality, and resource temperature are indicated. Uses of the energy that seem appropriate to the situation both now and in the near future at Hawthorne are described. The essential institutional requirements for geothermal energy development are discussed, including the financial, environmental, and legal and regulatory aspects. The various steps that are necessary to accomplish the construction of the geothermal district heating system are described.

  7. Geothermal energy: clean power from the Earth's heat

    USGS Publications Warehouse

    Duffield, Wendell A.; Sass, John H.

    2003-01-01

    Societies in the 21st century require enormous amounts of energy to drive the machines of commerce and to sustain the lifestyles that many people have come to expect. Today, most of this energy is derived from oil, natural gas, and coal, supplemented by nuclear power. Local exceptions exist, but oil is by far the most common source of energy worldwide. Oil resources, however, are nonrenewable and concentrated in only a few places around the globe, creating uncertainty in long-term supply for many nations. At the time of the Middle East oil embargo of the 1970s, about a third of the United States oil supply was imported, mostly from that region. An interruption in the flow of this import disrupted nearly every citizen’s daily life, as well as the Nation’s economy. In response, the Federal Government launched substantial programs to accelerate development of means to increasingly harness “alternative energies”—primarily biomass, geothermal, solar, and wind. The new emphasis on simultaneously pursuing development of several sources of energy recognized the timeless wisdom found in the proverb of “not putting all eggs in one basket.” This book helps explain the role that geothermal resources can play in helping promote such diversity and in satisfying our Nation’s vast energy needs as we enter a new millennium. For centuries, people have enjoyed the benefits of geothermal energy available at hot springs, but it is only through technological advances made during the 20th century that we can tap this energy source in the subsurface and use it in a variety of ways, including the generation of electricity. Geothermal resources are simply exploitable concentrations of the Earth’s natural heat (thermal energy). The Earth is a bountiful source of thermal energy, continuously producing heat at depth, primarily by the decay of naturally occurring radioactive isotopes—principally of uranium, thorium, and potassium—that occur in small amounts in all rocks

  8. 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.

  9. Seismotectonics of the Cerro Prieto Geothermal Field, Baja California, Mexico.

    NASA Astrophysics Data System (ADS)

    Rebollar, C. J.; Reyes, L. M.; Quintanar, L.; Arellano, J. F.

    2002-12-01

    We studied the background seismic activity in the Cerro Prieto geothermal field (CPGF) using a network of 21 digital stations. Earthquakes are located below the exploitation area of the CPGF, between 3 and 12 km depth, within the basement. Earthquakes follow roughly a N30°E trend perpendicular to the Cerro Prieto fault. This activity is located on a horst-like structure below the geothermal field and coincides with the zone of maximum subsidence in the CPGF. Two earthquake swarms occurred along the SE-NW strike of the Cerro Prieto fault and in the neighborhood of the Cerro Prieto volcano. Magnitudes range from -0.3 to 2.5. A Vp/Vs=1.91 ratio of the activity below the volcano suggests a water-saturated medium and/or a partial-melt medium. We calculated 76 focal mechanisms of individual events. On June 1 and September 10, 1999, two earthquakes of Mw 5.2 and 5.3 occurred in the basement at depths of 7.4 and 3.8 km below the CPGF. Maximum peak accelerations above the hypocenter ranged from 128.0 to 432.0 cm/s2. Waveform modeling results in a fault geometries given by strike=236°, dip=60°, rake=-58° (normal) and strike=10°, dip=90°, rake=159° (right lateral strike-slip) for the June and September events. Observed triangular source time function of 0.7 seconds and a double source with a total duration of 1.9 seconds for the June and September events were used to calculate the synthetics seismograms. Static stress drops and seismic moments for the June and September events are: Δ\\sigma=82.5 MPa (825 bars), Mo= 7.65x1016 Nm (7.65x1023 dyne-cm) and Δ\\sigma=31.3 MPa (313 bars) and Mo=1.27x1017 Nm (1.27x1024 dyne-cm). These stress drops are typical of continental events rather than stress drops of events originated in spreading centers. We concluded from the focal mechanisms of the background seismicity and June and September 1999 events, that a complex stress environment exits in the CPGF due to the continual thinning of the crust in the Cerro Prieto basin.

  10. Heterogeneous surface displacement pattern at the Hatchobaru geothermal field inferred from SAR interferometry time-series

    NASA Astrophysics Data System (ADS)

    Ishitsuka, Kazuya; Tsuji, Takeshi; Matsuoka, Toshifumi; Nishijima, Jun; Fujimitsu, Yasuhiro

    2016-02-01

    We estimated surface displacements using persistent scatterer SAR interferometry (PS-InSAR) around the Hatchobaru geothermal field, Japan, from 18 ALOS/PALSAR images acquired from July 2007 to December 2010. Generally, geothermal fields, covered with natural targets such as rocky terrain and vegetation, have been one of the difficult targets for PS-InSAR analysis. However, we applied space adaptive filtering to increase the number of pixels for measuring surface displacement. The results of our analysis demonstrate ground subsidence with decaying velocity over the observation period around the geothermal field. The spatial pattern of ground subsidence includes sharp boundaries of subsidence that can be interpreted as fault traces. We demonstrated the usefulness of PS-InSAR analysis with the space adaptive filtering to estimate surface displacements with high spatial resolution and high spatial density around a geothermal field.

  11. Discovery and geology of the Desert Peak geothermal field: a case history. Bulletin 97

    SciTech Connect

    Benoit, W.R.; Hiner, J.E.; Forest, R.T.

    1982-09-01

    A case history of the exploration, development (through 1980), and geology of the Desert Peak geothermal field is presented. Sections on geochemistry, geophysics, and temperature-gradient drilling are included.

  12. 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.

  13. Evaluation of geothermal energy in Arizona. Arizona geothermal planning/commercialization team. Quarterly topical progress report, July 1-September 30, 1980

    SciTech Connect

    White, D.H.; Mancini, F.; Goldstone, L.A.; Malysa, L.

    1980-01-01

    Progress is reviewed on the following: area development plans, evaluation of geothermal applications, continued evaluation of geothermal resources, engineering and economic analyses, technical assistance in the state of Arizona, the impact of various growth patterns upon geothermal energy development, and the outreach program. (MHR)

  14. Identification of fluid-flow paths in the Cerro Prieto geothermal field

    SciTech Connect

    Halfman, S.E.; Lippmann, M.J.; Zelwer, R.; Howard, J.H.

    1982-05-01

    A hydrogeologic model of the Cerro Prieto geothermal field has been developed based on geophysical and lithologic well logs, downhole temperature, and well completion data from about 90 deep wells. The hot brines seem to originate in the eastern part of the field, flowing in a westward direction and rising through gaps in the shaly layers which otherwise act as partial caprocks to the geothermal resource.

  15. Forecasting Induced Seismicity In Deep Geothermal Energy Projects

    NASA Astrophysics Data System (ADS)

    Király, Eszter; Gischig, Valentin; Karvounis, Dimitrios; Heiniger, Lukas; Wiemer, Stefan

    2014-05-01

    The decision to phase out nuclear power in Switzerland by 2034 accelerated research on deep geothermal energy, which has the ability to contribute to long-term energy resources. Induced seismicity occurring during early stimulation periods in deep geothermal projects of past years in Switzerland, however, clearly document our limited understanding of the processes at depth that lead to significant seismic hazard and that may influence public acceptance of future projects. Controlling induced seismicity related to deep geothermal projects with adaptive warning systems require models that are forward looking, dynamically updated on the fly as new data arrive and probabilistic in the sense that the inherent uncertainties in our understanding of the processes and in the required model parameters. We currently develop a fully coupled non-linear hydraulic-seismic 3D model joint with a hazard assessment procedure. The goal is to improve the forecasting skill owing to validated physical constraints. As a first step, we seek to answer the question: is it possible to forecast the seismic response of the geothermal site during and after stimulation based on observed seismicity and hydraulic data? Our goal is to find the most suitable model to date for forecasting induced micro-seismicity and unexpected large events in geothermal systems. In order to do so, available stochastic and hybrid models are tested and ranked such as Epidemic Type Aftershock Sequence models, models developed by Shapiro and his research group and two types of geomechanical seed models incorporating linear and non-linear fluid flow. The aim is to balance model prediction performance and model complexity: which parameters are necessary to forecast seismicity well, and which are eventually those that increase model complexity but do not give better results. All tests are performed on the Basel 2006 dataset. Testing is carried out along the guidelines of the Collaboratory for the Study of Earthquake

  16. 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.

  17. 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.

  18. Buried Treasure: The Environmental, Economic, and Employment Benefits of Geothermal Energy (Revised)

    SciTech Connect

    Not Available

    2004-11-01

    This new publication supplants older DOE publications regarding environmental impacts, providing updated and new information on environmental, economic, and employment benefits and impacts of geothermal energy.

  19. Energy policy act of 1992 opens doors for independent geothermal power producers

    SciTech Connect

    Mock, John E.

    1993-01-28

    The Energy Policy Act of 1992 embraces and implements many of the actions recommended by the President in the National Energy Strategy. Independent geothermal power producers may be direct beneficiaries of 1) further deregulation of IPPs through their exemption from the provisions of the Public Utility Holding Company Act and 2) potentially freer access to utility-owned transmission facilities. However, these doors will not be fully opened to geothermal energy until this resource can compete with other fuels in cost considerations. While changes in public policy, such as inclusion of externalities in the price of power or financial penalties on carbon dioxide emissions, will level the playing field somewhat, reductions in cost will be the ultimate marketing tool. This is particularly critical in the economics of power derived from "new," as yet undiscovered reservoirs which will reflect the high costs of today's exploration methods. The Department of Energy's geothermal R&D program, in cooperation with industry, is undertaking, as described in this paper, to achieve the technology cost reductions needed to permit this resource to enjoy a status equal to or better than that of competing fuels at the utility least-cost bargaining table.

  20. Radon and ammonia transects across the Cerro Prieto geothermal field

    SciTech Connect

    Semprini, L.; Kruger, P.

    1981-01-01

    Radon and ammonia transects, conducted at the Cerro Prieto geothermal field, involve measurement of concentration gradients at wells along lines of structural significance in the reservoir. Analysis of four transects showed radon concentrations ranging from 0.20 to 3.60 nCi/kg and ammonia concentrations from 17.6 to 59.3 mg/l. The data showed the lower concentrations in wells of lowest enthalpy fluid and the higher concentrations in wells of highest enthalpy fluid. Linear correlation analysis of the radon-enthalpy data indicated a strong relationship, with a marked influence by the two-phase conditions of the produced fluid. It appears that after phase separation in the reservoir, radon achieves radioactive equilibrium between fluid and rock, suggesting that the phase separation occurs well within the reservoir. A two-phase mixing model based on radon-enthalpy relations allows estimation of the fluid phase temperatures in the reservoir. Correlations of ammonia concentration with fluid enthalpy suggests an equilibrium partitioning model in which enrichment of ammonia correlates with higher enthalpy vapor.

  1. Results of investigations at the Ahuachapan geothermal field, El Salvador

    SciTech Connect

    Dennis, B.; Goff, F.; Van Eeckhout, E.; Hanold, B.

    1990-04-01

    Well logging operations were performed in eight of the geothermal wells at Ahuachapan. High-temperature downhole instruments, including a temperature/rabbit, caliper, fluid velocity spinner/temperature/pressure (STP), and fluid sampler, were deployed in each well. The caliper tool was used primarily to determine if chemical deposits were present in well casings or liners and to investigate a suspected break in the casing in one well. STP logs were obtained from six of the eight wells at various flow rates ranging from 30 to 80 kg/s. A static STP log was also run with the wells shut-in to provide data to be used in the thermodynamic analysis of several production wells. The geochemical data obtained show a system configuration like that proposed by C. Laky and associates in 1989. Our data indicate recharge to the system from the volcanic highlands south of the field. Additionally, our data indicate encroachment of dilute fluids into deeper production zones because of overproduction. 17 refs., 50 figs., 10 tabs.

  2. Analysis of pressure transient data from the Sumikawa geothermal field

    SciTech Connect

    Ishido, T.; Kikuchi, T.; yano, Y.; Miyazaki, Y.; Nakao, S.; Hatakeyama, K.

    1992-01-01

    The permeability structure of the Sumikawa geothermal field in northern Japan has been the subject of an extensive pressure-transient testing investigation since 1986. In this paper, various pertinent data sets are presented and analyzed, including results showing reservoir heterogeneity (i.e. boundary) effects and apparent double porosity behavior. Interference tests between wells SB-3 and SD-2 (both of which have feedpoints in dacitic layers in the ''marine-volcanic complex'' formation) were carried out during 1990. The results have been interpreted to indicate the presence of a moderately high permeability ({approx} 4 darcy-meters) layer with two impermeable boundaries intersecting at a right angle. The 1988 pressure buildup data for well SN-7D are also explained by assuming two impermeable boundaries in a high transmissivity reservoir within the deep ''granodiorite'' formation. Interference tests between wells S-4 and KY-1 have suggested that a very permeable north-south channel is present in the ''altered andesite'' layer. Although the response was successfully interpreted using an ''anisotropic line-source model'' by Garg et al. (1991), a ''double porosity channel model'' seems to be particularly applicable for explaining both the short-term and long-term behavior observed in this series of tests.

  3. Field Studies of Geothermal Reservoirs Rio Grande Rift, New Mexico

    SciTech Connect

    James C Witcher

    2002-07-30

    The Rio Grande rift provides an excellent field laboratory to study the nature of geothermal systems in an extensional environment. Much of the geologic complexity that is found in the Basin and Range is absent because the rift is located on cratonic crust with a thin and well-characterized Phanerozoic stratigraphy and tectonic history. On the other hand, the Neogene thermo-tectonic history of the rift has many parallels with the Basin and Range to the west. The geology of the southern Rio Grande rift is among the best characterized of any rift system in the world. Also, most geologic maps for the region are rather unique in that detailed analyses of Quaternary stratigraphic and surficial unit are added in concert with the details of bedrock geology. Pleistocene to Holocene entrenchment of the Rio Grande and tributaries unroofs the alteration signatures and permeability attributes of paleo outflow plumes and upflow zones, associated with present-day, but hidden or ''blind,'' hydrothermal systems at Rincon and San Diego Mountain.

  4. S-wave Anisotropy and Crack Distribution at the Coso Geothermal Field, California

    NASA Astrophysics Data System (ADS)

    Vlahovic, G.; Elkibbi, M.; Rial, J. A.

    2001-05-01

    The Coso geothermal area is located along the eastern front of Sierra Nevada, in the southwestern Basin and Range Province. Seismic activity averaging more than 20 microearthquakes per day is the result of both regional tectonics and geothermal production activity [Malin, 1994]. Microseismicity is monitored by the Coso Digital Downhole Seismic Network (CDDSN) recording at 2 ms sampling rate. Continuous operation of the CDDSN since 1990 created a data set of exceptional richness and continuity. We used data accumulated from January 1999 through June 2000 for the study of S wave anisotropy and crack distribution. Understanding the faults and associated fracture system in Coso is fundamental for efficient long-term energy extraction and micro-tectonic models of the area. Strike of cracks in the shear-wave window of each station was determined by plotting rose diagrams of the fast shear-wave polarization directions. Each rose diagram has a clear dominant polarization direction, interpreted as the direction of the local fracture system. Three dominant strike groups were observed: 0 - 20 NE, 40 - 60 NE and 20 - 40 NW. These results are consistent with subsurface crack directions determined by Lou and Rial [1997], and with photographically and magnetically mapped alignments on the surface [Moore and Erskine, 1990], as well as with deep borehole observations. Four stations centered in the geothermal production area were selected for detailed study of variation of arrival time delays between fast and slow shear-waves and changes of polarization of leading shear-wave with time. Preliminary results suggest that for one station in the northeast end of the geothermal field, there is an increase in number of secondary fractures with strike from 10 NW to 30 NE in the data from January to June of 2000, relative to data from January to June of 1999. Statistical significance and reasons for such a change will be further studied, although it is interesting to note that this station

  5. Hot dry rock geothermal energy -- a renewable energy resource that is ready for development now

    SciTech Connect

    Brown, D.W.; Potter, R.M.; Myers, C.W.

    1990-01-01

    Hot dry rock (HDR) geothermal energy, which utilizes the natural heat contained in the earth's crust, is a very large and well-distributed resource of nonpolluting, and essentially renewable, energy that is available globally. Its use could help mitigate climatic change and reduce acid rain, two of the major environmental consequences of our ever-increasing use of fossil fuels for heating and power generation. In addition, HDR, as a readily available source of indigenous energy, can reduce our nations's dependence on imported oil, enhancing national security and reducing our trade deficit. The earth's heat represents an almost unlimited source of energy that can begin to be exploited within the next decade through the HDR heat-mining concept being actively developed in the United States, Great Britain, Japan, and several other countries. On a national scale we can begin to develop this new source, using it directly for power generation or for direct-heat applications, or indirectly in hybrid geothermal/fossil-fuel power plants. In the HDR concept, which has been demonstrated in the field in two different applications and flow- tested for periods up to one year, heat is recovered from the earth by pressurized water in a closed-loop circulation system. As a consequence, minimal effluents are released to the atmosphere, and no wastes are produced. This paper describes the nature of the HDR resource and the technology required to implement the heat-mining concept. An assessment of the requirements for establishing HDR feasibility is presented in the context of providing a commercially competitive energy source.

  6. Does shallow geothermal energy use threaten groundwater ecosystem functions?

    NASA Astrophysics Data System (ADS)

    Brielmann, Heike; Schmidt, Susanne I.; Ferraro, Francesco; Schreglmann, Kathrin; Griebler, Christian; Lueders, Tillmann

    2010-05-01

    Today, the use of geothermal energy is strongly promoted as an alternative and sustainable source of energy. However, regarding the authorization, regulation and monitoring of such facilities with respect to possible environmental impacts, a severe lack of knowledge has been identified. Aquifers are not only abiotic reservoirs of water and sediment, but they are complex ecosystems harbouring an almost untapped diversity of microorganisms and fauna. Intrinsic groundwater organisms are highly adapted to extremely oligotrophic, but stable conditions including temperature. At the same time, groundwater biota are the key drivers of important ecosystem services, especially functions connected to water quality. So what happens if groundwater biota need to cope with sudden temperature dynamics caused by GSHP use? Potential effects of thermal use on pristine aquifers, and on groundwater systems already facing enhanced loads of nutrients or contamination require urgent scientific attention. Within this project, we have assessed - both in the field and in the laboratory - the impacts of temperature discharge and withdrawal on biotic parameters and functional characteristics of exemplary shallow groundwater systems. In the field, aquifer microbes did not show significant impacts under increased temperatures in terms of total cell numbers, selected enzyme activities and carbon production. However, bacterial diversity clearly increased with temperature, accompanied by the appearance of new bacterial lineages and the disappearance of others. On the contrary, faunal diversity decreased with temperature, highlighting the temperature sensitivity of groundwater invertebrates. These results demonstrate that aquifer thermal energy discharge can affect intrinsic aquifer biotic populations, while at the same time being only one of several drivers contributing to total variability connected to seasonal dynamics and spatial heterogeneity. In laboratory column experiments covering a larger

  7. Geothermal pump down-hole energy regeneration system

    DOEpatents

    Matthews, Hugh B.

    1982-01-01

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

  8. Hot Dry Rock geothermal energy moving towards practical applications

    SciTech Connect

    Duchane, D.

    1994-03-01

    The thermal energy present in hot rock at depth is a vast resource which has so far been tapped only in those unusual locations where natural fluids exist to transport that energy to the surface. For the past twenty years work has been underway at the Los Alamos National Laboratory to develop the technology to access and recovery the heat present in rock which is hot but contains no natural mobile fluid. The world`s first plant capable of sustained production of geothermal energy from HDR was completed in 1991. This facility combined an artificial geothermal reservoir of sufficient size and high enough temperature to deliver large amounts of useful energy with a surface plant built to power industry standards and capable of sustained, routine operation. During the past two years, extended testing at Fenton Hill has demonstrated that energy can be extracted from HDR on a continuous basis. Thermal energy was produced continuously at a rate of about 4 MW in two test phases lasting 112 and 55 days, respectively, and intermittently for a period of 7 1/2 months between the continuous test segments. Temperature measurements at the surface and at depth indicated no decline in the average discharge temperature of water from the reservoir over the span of the test. In fact, tracer testing indicated that access of the circulating water to the hot reservoir rock improved as the test proceeded.

  9. A sustainability analysis of geothermal energy development on the island of Dominica

    NASA Astrophysics Data System (ADS)

    Edwards, Kiyana Marie-Jose

    Dominica is heavily dependent on fossil fuels to meet its electricity generation needs. Dominica's volcanic origin and current volcanic activity allow the island to be an ideal place for the production of geothermal energy. Once geothermal exploration and development has begun in Dominica, it is uncertain whether the efforts will produce an environmentally, economically and socially feasible exploitation of the resource. Using content analysis and cost benefit analysis, this study examined the impacts of geothermal energy development based on the triple bottom line of sustainability for the Wotten Waven community, as well as the island as a whole. The results indicate that this project will have an overall positive impact on the triple bottom line of sustainability for Dominica. Therefore, geothermal energy may provide substantial net benefits to economic and sustainable development of the island. Assessing the sustainability of geothermal development is important as Dominica begins to produce geothermal energy.

  10. Seismic monitoring of a flow test in the Salton Sea Geothermal Field

    SciTech Connect

    Jarpe, S.P.; Kasameyer, P.W.; Johnston, C.

    1989-06-01

    The purpose of this seismic monitoring project was to characterize in detail the micro-seismic activity related to the flow-injection test in the Salton Sea Geothermal Field. Our goal was to determine if any sources of seismic energy related to the test were observable at the surface, using both conventional seismic network techniques and relatively newer array techniques. These methods allowed us to detect and locate both impulsive microearthquakes and continuous sources of seismic energy. Our network, which was sensitive enough to be triggered by magnitude 0.0 or larger events, found no impulsive microearthquakes in the vicinity of the flow test in the 8 month period before the test and only one event during the flow test. We have observed some continuous seismic noise sources that may be attributed to the flow test. 4 refs., 4 figs.

  11. Geothermal energy resource investigations at Mt. Spurr, Alaska

    SciTech Connect

    Turner, D.L.; Wescott, E.M.

    1986-12-01

    Spurr volcano is a composite Quaternary cone of largely andesitic composition located on the west side of Cook Inlet about 80 miles west of Anchorage and about 40 miles from the Beluga electrical transmission line. Geologic mapping (Plate 1-1) shows that the present summit depression was produced by a Mt. St. Helens-type sector collapse, rather than by a caldera collapse. Geochronologic and previous tephrachronologic studies show that there has been an active magmatic system at Spurr volcano during the late Pleistocene-to-Holocene time interval that is of critical interest for geothermal energy resource assessment. Major effort was devoted to geochemical and geophysical surveys of the accessible area south of Mt. Spurr, in addition to geologic mapping and geochronologic studies. Many coincident mercury and helium anomalies were found, suggesting the presence of geothermal systems at depth. Extremely large electrical self-potential anomalies were also found, together with extensive zones of low resistivity discovered by our controlled-source audiomagnetotelluric survey. The juxtaposition of all of these different types of anomalies at certain areas on the south slope of Crater Peak indicates the presence of a geothermal system which should be accessible by drilling to about 2000 ft depth. It is also evident that there is a strong volcanic hazard to be evaluated in considering any development on the south side of Mt. Spurr. This hazardous situation may require angle drilling of production wells from safer areas and placement of power generation facilities at a considerable distance from hazardous areas.

  12. Geothermal Energy Market Study on the Atlantic Coastal Plain: Technical Feasibility of use of Eastern Geothermal Energy in Vacuum Distillation of Ethanol Fuel

    SciTech Connect

    1981-04-01

    The DOE is studying availability, economics, and uses of geothermal energy. These studies are being conducted to assure maximum cost-effective use of geothermal resources. The DOE is also aiding development of a viable ethanol fuel industry. One important point of the ethanol program is to encourage use of non-fossil fuels, such as geothermal energy, as process heat to manufacture ethanol. Geothermal waters available in the eastern US tend to be lower in temperature (180 F or less) than those available in the western states (above 250 F). Technically feasible use of eastern geothermal energy for ethanol process heat requires use of technology that lowers ethanol process temperature requirements. Vacuum (subatmospheric) distillation is one such technology. This study, then, addresses technical feasibility of use of geothermal energy to provide process heat to ethanol distillation units operated at vacuum pressures. They conducted this study by performing energy balances on conventional and vacuum ethanol processes of ten million gallons per year size. Energy and temperature requirements for these processes were obtained from the literature or were estimated (for process units or technologies not covered in available literature). Data on available temperature and energy of eastern geothermal resources was obtained from the literature. These data were compared to ethanol process requirements, assuming a 150 F geothermal resource temperature. Conventional ethanol processes require temperatures of 221 F for mash cooking to 240 F for stripping. Fermentation, conducted at 90 F, is exothermic and requires no process heat. All temperature requirements except those for fermentation exceed assumed geothermal temperatures of 150 F. They assumed a 130 millimeter distillation pressure for the vacuum process. It requires temperatures of 221 F for mash cooking and 140 F for distillation. Data indicate lower energy requirements for the vacuum ethanol process (30 million BTUs per

  13. Characterization of deep geothermal energy resources using Electro-Magnetic methods, Belgium

    NASA Astrophysics Data System (ADS)

    Loveless, Sian; Harcout-Menou, Virginie; De Ridder, Fjo; Claessens, Bert; Laenen, Ben

    2014-05-01

    Sedimentary basins in Northwest Europe have significant potential for low to medium enthalpy, deep geothermal energy resources. These resources are currently assessed using standard exploration techniques (seismic investigations followed by drilling of a borehole). This has enabled identification of geothermal resources but such techniques are extremely costly. The high cost of exploration remains one of the main barriers to geothermal project development due to the lack of capital in the geothermal industry. We will test the possibility of using the Electro-Magnetic (EM) methods to aid identification of geothermal resources in conjunction with more traditional exploration methods. An EM campaign could cost a third of a seismic campaign and is also often a passive technology, resulting in smaller environmental impacts than seismic surveys or drilling. EM methods image changes in the resistivity of the earth's sub-surface using natural or induced frequency dependant variations of electric and magnetic fields. Changes in resistivity can be interpreted as representing different subsurface properties including changes in rock type, chemistry, temperature and/or hydraulic transmissivity. While EM techniques have proven to be useful in geothermal exploration in high enthalpy areas in the last 2-3 years only a handful of studies assess their applicability in low enthalpy sedimentary basins. Challenges include identifying which sub-surface features cause changes in electrical resistivity as low enthalpy reservoirs are unlikely to exhibit the hydrothermally altered clay layer above the geothermal aquifer that is typical for high enthalpy reservoirs. Yet a principal challenge is likely to be the high levels of industrialisation in the areas of interest. Infrastructure such as train tracks and power cables can create a high level of background noise that can obfuscate the relevant signal. We present our plans for an EM campaign in the Flemish region of Belgium. Field

  14. Geothermal energy in the United States; Part II, Assessment of resources

    USGS Publications Warehouse

    Williams, D.L.

    1976-01-01

    Geothermal energy-from heat deep inside the Earth- is a vast potential source of power. This article is the second part of a series on geothermal energy, the first part of which was in volume 8, number 1, of the Earthquake Information Bulletin (January-February 1976). Part 1 of this series described the categories of the geothermal resource base. 

  15. The National Energy Strategy - The role of geothermal technology development: Proceedings

    SciTech Connect

    Not Available

    1990-01-01

    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 industry. Topics in this year's conference included Hydrothermal Energy Conversion Technology, Hydrothermal Reservoir Technology, Hydrothermal Hard Rock Penetration Technology, Hot Dry Rock Technology, Geopressured-Geothermal Technology and Magma Energy Technology. Each individual paper has been cataloged separately.

  16. Health and safety implications of alternative energy technologies. I. Geothermal and biomass

    NASA Astrophysics Data System (ADS)

    Watson, A. P.; Etnier, E. L.

    1981-07-01

    An evaluation of potential occupational and public health aspects of geopressure, hydrothermal, hot dry rock, silviculture, crop and animal residues, fermentable plant products, municipal waste, and plantation energy technologies has been performed. Future development of these energy options in the United States will contain hazards that could easily be eliminated by safer equipment design and common-sense attention to operation and maintenance. Occupational exposure to hydrogen sulfide gas occurs near all geothermal sites and wherever organic matter decomposes anaerobically. Respiratory damage has occurred to laborers in geothermal fields, while farm workers have been fatally overcome when employed near agitating liquid manure systems. However, the most frequent and severe of reported injuries to geothermal workers is dermal exposure to caustic sludges produced by H2S abatement systems. Principal health and safety considerations of biomass pathways are directly related to the diffuse nature of solar energy fixation by photosynthesis and subsequent transfer to animal food chains. Since the potential fuel is in an unconcentrated form, cultivation, harvest, and transport are necessarily laborintensive. Thus, a significant potential for occupational injuries and fatalities exists. Of all biomass systems evaluated, direct burning of solid fuels presents the greatest public health risk. Data are presented to characterize the population at risk and the frequency and severity of injuries.

  17. Geothermal handbook

    USGS Publications Warehouse

    1976-01-01

    The Bureau of Land Management offered over 400,000 hectares (one million acres) for geothermal exploration and development in 1975, and figure is expected to double this year. The Energy Research and Development Administration hopes for 10-15,000 megawatts of geothermal energy by 1985, which would require, leasing over 16.3 million hectares (37 million acres) of land, at least half of which is federal land. Since there is an 8 to 8-1/2 year time laf between initial exploration and full field development, there would have to be a ten-fold increase in the amount of federal land leased within the next three years. Seventy percent of geothermal potential, 22.3 million hectares (55 million acres), is on federal lands in the west. The implication for the Service are enormous and the problems immediate. Geothermal resource are so widespread they are found to some extent in most biomes and ecosystems in the western United States. In most cases exploitation and production of geothermal resources can be made compatible with fish and wildlife management without damage, if probable impacts are clearly understood and provided for before damage has unwittingly been allowed to occur. Planning for site suitability and concern with specific operating techniques are crucial factors. There will be opportunities for enhancement: during exploration and testing many shallow groundwater bodies may be penetrated which might be developed for wildlife use. Construction equipment and materials needed for enhancement projects will be available in areas heretofore considered remote projects will be available in areas heretofore considered remote by land managers. A comprehensive knowledge of geothermal development is necessary to avoid dangers and seize opportunities. This handbook is intended to serve as a working tool in the field. It anticipated where geothermal resource development will occur in the western United States in the near future. A set of environmental assessment procedures are

  18. Energy and process substitution in the frozen-food industry: geothermal energy and the retortable pouch

    SciTech Connect

    Stern, M.W.; Hanemann, W.M.; Eckhouse, K.

    1981-12-01

    An assessment is made of the possibilities of using geothermal energy and an aseptic retortable pouch in the food processing industry. The focus of the study is on the production of frozen broccoli in the Imperial Valley, California. Background information on the current status of the frozen food industry, the nature of geothermal energy as a potential substitute for conventional fossil fuels, and the engineering details of the retortable pouch process are covered. The analytical methodology by which the energy and process substitution were evaluated is described. A four-way comparison of the economics of the frozen product versus the pouched product and conventional fossil fuels versus geothermal energy was performed. A sensitivity analysis for the energy substitution was made and results are given. Results are summarized. (MCW)

  19. The structural architecture of the Los Humeros volcanic complex and geothermal field, Trans-Mexican Volcanic Belt, Central Mexico

    NASA Astrophysics Data System (ADS)

    Norini, Gianluca; Groppelli, Gianluca; Sulpizio, Roberto; Carrasco Núñez, Gerardo; Davila Harris, Pablo

    2014-05-01

    The development of geothermal energy in Mexico is a very important goal, given the presence of a large heat anomaly, associated with the Trans-Mexican Volcanic Belt, the renewability of the resource and the low environmental impact. The Quaternary Los Humeros volcanic complex is an important geothermal target, whose evolution involved at least two caldera events, that alternated with other explosive and effusive activity. The first caldera forming event was the 460 ka eruption that produced the Xaltipan ignimbrite and formed a 15-20 km wide caldera. The second collapse event occurred 100 ka with the formation of the Zaragoza ignimbrite and a nested 8-10 km wide caldera. The whole volcano structure, the style of the collapses and the exact location of the calderas scarps and ring faults are still a matter of debate. The Los Humeros volcano hosts the productive Los Humeros Geothermal Field, with an installed capacity of 40 MW and additional 75 MW power plants under construction. Recent models of the geothermal reservoir predict the existence of at least two reservoirs in the geothermal system, separated by impermeable rock units. Hydraulic connectivity and hydrothermal fluids circulation occurs through faults and fractures, allowing deep steam to ascend while condensate flows descend. As a consequence, the plans for the exploration and exploitation of the geothermal reservoir have been based on the identification of the main channels for the circulation of hydrothermal fluids, constituted by faults, so that the full comprehension of the structural architecture of the caldera is crucial to improve the efficiency and minimize the costs of the geothermal field operation. In this study, we present an analysis of the Los Humeros volcanic complex focused on the Quaternary tectonic and volcanotectonics features, like fault scarps and aligned/elongated monogenetic volcanic centres. Morphostructural analysis and field mapping reveal the geometry, kinematics and dynamics of

  20. Utilization of geothermal energy for agribusiness development in southwestern New Mexico

    SciTech Connect

    Lansford, R.R.; Chaturvedi, L.N.; Abernathy, G.H.; Creel, B.J.; Nelson, D.C.; Cotter, D.J.; Gollehon, N.R.; Clevenger, T.S.; Patterson, R.C.

    1980-09-01

    Animas Valley in southwestern New Mexico is an agricultural area of high geothermal energy potential. Geothermal water at boiling temperature is encountered at 88 feet below the ground surface at the center of the geothermal anomaly. A feasibility study for utilization of this geothermal resource for greenhouse operation indicates that savings of as much as $143,000 annually could be realized through replacing natural gas by geothermal water for space heating of a five acre greenhouse site. Specific economic analysis for a meat pre-cooking facility using geothermal water indicates that such an operation would not be economical due to the non-availability of adequate quantities of fed beef in the area and the cost of construction of a complex using geothermal water for pre-cooking.

  1. Geothermal resources and energy complex use in Russia

    NASA Astrophysics Data System (ADS)

    Svalova, V.

    2009-04-01

    Geothermal energy use is the perspective way to clean sustainable development of the world. Russia has rich high and low temperature geothermal resources and makes good steps in their use. In Russia the geothermal resources are used predominantly for heat supply both heating of several cities and settlements on Northern Caucasus and Kamchatka with a total number of the population 500000. Besides in some regions of country the deep heat is used for greenhouses of common area 465000 m2. Most active the hydrothermal resources are used in Krasnodar territory, Dagestan and on Kamchatka. The approximately half of extracted resources is applied for heat supply of habitation and industrial puttings, third - to a heating of greenhouses, and about 13 % - for industrial processes. Besides the thermal waters are used approximately on 150 health resorts and 40 factories on bottling mineral water. The most perspective direction of usage of low temperature geothermal resources is the use of heat pumps. This way is optimal for many regions of Russia - in its European part, on Ural and others. The electricity is generated by some geothermal power plants (GeoPP) only in the Kamchatka Peninsula and Kuril Islands. At present three stations work in Kamchatka: Pauzhetka GeoPP (11MW e installed capacity) and two Severo-Mutnovka GeoPP ( 12 and 50 MWe). Moreover, another GeoPP of 100 MVe is now under preparation in the same place. Two small GeoPP are in operation in Kuril's Kunashir Isl, and Iturup Isl, with installed capacity of 2,б MWe and 6 MWe respectively. There are two possible uses of geothermal resources depending on structure and properties of thermal waters: heat/power and mineral extraction. The heat/power direction is preferable for low mineralized waters when valuable components in industrial concentration are absent, and the general mineralization does not interfere with normal operation of system. When high potential geothermal waters are characterized by the high

  2. Fluid flow model of the Cerro Prieto Geothermal Field based on well log interpretation

    SciTech Connect

    Halfman, S.E.; Lippmann, M.J.; Zelwe, R.; Howard, J.H.

    1982-08-10

    The subsurface geology of the Cerro Prieto geothermal field was analyzed using geophysical and lithologic logs. The distribution of permeable and relatively impermeable units and the location of faults are shown in a geologic model of the system. By incorporating well completion data and downhole temperature profiles into the geologic model, it was possible to determine the direction of geothermal fluid flow and the role of subsurface geologic features that control this movement.

  3. Fluid flow model of the Cerro Prieto geothermal field based on well log interpretation

    SciTech Connect

    Halfman, S.E.; Lippmann, M.J.; Zelwer, R.; Howard, J.H.

    1982-10-01

    The subsurface geology of the Cerro Prieto geothermal field was analyzed using geophysical and lithologic logs. The distribution of permeable and relatively impermeable units and the location of faults are shown in a geologic model of the system. By incorporating well completion data and downhole temperature profiles into the geologic model, it was possible to determine he direction of geothermal fluid flow and the role of subsurface geologic features that control this movement.

  4. Taking the High Ground: Geothermal's Place in the Revolving Energy Market

    SciTech Connect

    Jaros, Richard

    1992-03-24

    It's a genuine privilege for me to be here today. As Dr. Mock mentioned, I have been President of California Energy for not yet three months and have a total tenure in the industry of only one year. As a newcomer to the industry, I am honored to address this group and share my views on ''The Opportunities and Challenges for Expanding Geothermal Energy''. You will see that my outlook for our industry is generally optimistic, shaped in part, perhaps by a newcomer's enthusiasm, but largely I think by my analysis of the opportunities which are open to us as an industry. Many of you and your predecessors over the last 20 years pioneered the geothermal industry in the United States. The risks were great, the results sometimes rewarding, sometimes disappointing. Government and the private sector forged an alliance that moved the industry ahead. Developers, utilities and federal land managers worked together to bring projects on line. Government helped identify geothermal areas, in many cases doing exploration work. The geothermal pioneers had to form entirely new, multi-disciplinary teams to solve problems unique to this resource. From discovery of fields, to environmental mitigation, to management of reservoirs and all of the steps in between, new teams had to be assembled. Geologists, geochemists, hydrologists, reservoir engineers and drilling technologists now apply their skills. Even anthropologists and biologists routinely get into the act in the environmental assessment phase of development. The care that our industry is taking today to do the job right reflects a maturing industry with high standards of performance. To be sure, mistakes were made in the early years, but the industry learned from them. We all know the value of responsible development and resource management to the long-term future of our industry. Improvements in technology and more efficient operations have helped lower our costs and improve our competitiveness. Our industry's progress has also

  5. Energy Returned On Investment of Engineered Geothermal Systems Annual Report FY2010

    SciTech Connect

    Mansure, A.J.

    2010-12-31

    Energy Return On Investment (EROI) is an important figure of merit for assessing the viability of energy alternatives. EROI analyses of geothermal energy are either out of date or presented online with little supporting documentation. Often comparisons of energy systems inappropriately use 'efficiency' when EROI would be more appropriate. For geothermal electric power generation, EROI is determined by the electric energy delivered to the consumer compared to the energy consumed to build, operate, and decommission the facility.

  6. Niland development project geothermal loan guaranty: 49-MW (net) power plant and geothermal well field development, Imperial County, California: Environmental assessment

    SciTech Connect

    Not Available

    1984-10-01

    The proposed federal action addressed by this environmental assessment is the authorization of disbursements under a loan guaranteed by the US Department of Energy for the Niland Geothermal Energy Program. The disbursements will partially finance the development of a geothermal well field in the Imperial Valley of California to supply a 25-MW(e) (net) power plant. Phase I of the project is the production of 25 MW(e) (net) of power; the full rate of 49 MW (net) would be achieved during Phase II. The project is located on approximately 1600 acres (648 ha) near the city of Niland in Imperial County, California. Well field development includes the initial drilling of 8 production wells for Phase I, 8 production wells for Phase II, and the possible need for as many as 16 replacement wells over the anticipated 30-year life of the facility. Activities associated with the power plant in addition to operation are excavation and construction of the facility and associated systems (such as cooling towers). Significant environmental impacts, as defined in Council on Environmental Quality regulation 40 CFR Part 1508.27, are not expected to occur as a result of this project. Minor impacts could include the following: local degradation of ambient air quality due to particulate and/or hydrogen sulfide emissions, temporarily increased ambient noise levels due to drilling and construction activities, and increased traffic. Impacts could be significant in the event of a major spill of geothermal fluid, which could contaminate groundwater and surface waters and alter or eliminate nearby habitat. Careful land use planning and engineering design, implementation of mitigation measures for pollution control, and design and implementation of an environmental monitoring program that can provide an early indication of potential problems should ensure that impacts, except for certain accidents, will be minimized.

  7. 75 FR 33613 - Notice of the Carbon Sequestration-Geothermal Energy-Science Joint Workshop

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-14

    ...The DOE Geothermal Technologies Program, Office of Science- Geosciences Program and Office of Fossil Energy-Carbon Sequestration Program will be holding a joint workshop on Common Research Themes for Carbon Storage and Geothermal Energy, June 15-16, 2010. Experts from industry, academia, national labs, and State and Federal geological surveys will discuss geosciences research needs for......

  8. Evaluation of geothermal energy in Arizona. Quarterly topical progress report, April 1, 1981-June 30, 1981

    SciTech Connect

    White, D.H.

    1981-01-01

    Activities included the identification and delineation of geothermal prospects, the comparison of conventional energy use patterns with geothermal sources, the preparation of area development plans and the compilation of detailed economic and energy data for each area. Current emphasis is on commercialization. (MHR)

  9. Structural compartmentalisation of a geothermal system, the Torre Alfina field (central Italy)

    NASA Astrophysics Data System (ADS)

    Vignaroli, Gianluca; Pinton, Annamaria; De Benedetti, Arnaldo A.; Giordano, Guido; Rossetti, Federico; Soligo, Michele; Berardi, Gabriele

    2013-11-01

    Recent surging of renewed industrial interest in the exploration of low and medium enthalpy geothermal fields makes the accurate assessment of the geothermal potential essential to minimise uncertainties during both exploration and exploitation. The Torre Alfina field is a case of abandoned, but promising, geothermal field of central Italy where the roles of the internal structural setting and of the recharge areas on the hydrothermal circulation are largely unconstrained. In this paper, field structural data integrated with geomorphic lineament analysis document the occurrence of post-orogenic deformation structures controlling the compartmentalisation of the Torre Alfina geothermal field. Strike-slip and subordinate normal fault systems (with associated network fractures) cut and dislocate the internal architecture of the reservoir and prevent its hydraulic connection with Mount Cetona, considered to be the recharge area and where hydrothermal manifestation, including travertine deposition, occurs. 230Th/234U radiometric dating of superposed travertine units gives 200, 120 and 90 ka respectively, inferred to correspond to the age of the fossil hydrothermal circulation during tectonic activity. The results have been used for illustrating a new geological conceptual model for the Torre Alfina area where the geothermal system is composed of different compartments. Tectonic structures define the main boundaries between compartments, helping the understanding of why productive and non-productive wells were found in apparently similar structural settings within the Torre Alfina field.

  10. The Momotombo Geothermal Field, Nicaragua: Exploration and development case history study

    SciTech Connect

    1982-07-01

    This case history discusses the exploration methods used at the Momotombo Geothermal Field in western Nicaragua, and evaluates their contributions to the development of the geothermal field models. Subsequent reservoir engineering has not been synthesized or evaluated. A geothermal exploration program was started in Nicaragua in 1966 to discover and delineate potential geothermal reservoirs in western Nicaragua. Exploration began at the Momotombo field in 1970 using geological, geochemical, and geophysical methods. A regional study of thermal manifestations was undertaken and the area on the southern flank of Volcan Momotombo was chosen for more detailed investigation. Subsequent exploration by various consultants produced a number of geotechnical reports on the geology, geophysics, and geochemistry of the field as well as describing production well drilling. Geological investigations at Momotombo included photogeology, field mapping, binocular microscope examination of cuttings, and drillhole correlations. Among the geophysical techniques used to investigate the field sub-structure were: Schlumberger and electromagnetic soundings, dipole mapping and audio-magnetotelluric surveys, gravity and magnetic measurements, frequency domain soundings, self-potential surveys, and subsurface temperature determinations. The geochemical program analyzed the thermal fluids of the surface and in the wells. This report presents the description and results of exploration methods used during the investigative stages of the Momotombo Geothermal Field. A conceptual model of the geothermal field was drawn from the information available at each exploration phase. The exploration methods have been evaluated with respect to their contributions to the understanding of the field and their utilization in planning further development. Our principal finding is that data developed at each stage were not sufficiently integrated to guide further work at the field, causing inefficient use of

  11. Colorado geothermal commercialization program. Geothermal energy opportunities at four Colorado towns: Durango, Glenwood Springs, Idaho Springs, Ouray

    SciTech Connect

    Coe, B.A.; Zimmerman, J.

    1981-01-01

    The potential of four prospective geothermal development sites in Colorado was analyzed and hypothetical plans prepared for their development. Several broad areas were investigated for each site. The first area of investigation was the site itself: its geographic, population, economic, energy demand characteristics and the attitudes of its residents relative to geothermal development potential. Secondly, the resource potential was described, to the extent it was known, along with information concerning any exploration or development that has been conducted. The third item investigated was the process required for development. There are financial, institutional, environmental, technological and economic criteria for development that must be known in order to realistically gauge the possible development. Using that information, the next concern, the geothermal energy potential, was then addressed. Planned, proposed and potential development are all described, along with a possible schedule for that development. An assessment of the development opportunities and constraints are included. Technical methodologies are described in the Appendix. (MHR)

  12. Analysis of earthquake clustering and source spectra in the Salton Sea Geothermal Field

    NASA Astrophysics Data System (ADS)

    Cheng, Y.; Chen, X.

    2015-12-01

    The Salton Sea Geothermal field is located within the tectonic step-over between San Andreas Fault and Imperial Fault. Since the 1980s, geothermal energy exploration has resulted with step-like increase of microearthquake activities, which mirror the expansion of geothermal field. Distinguishing naturally occurred and induced seismicity, and their corresponding characteristics (e.g., energy release) is important for hazard assessment. Between 2008 and 2014, seismic data recorded by a local borehole array were provided public access from CalEnergy through SCEC data center; and the high quality local recording of over 7000 microearthquakes provides unique opportunity to sort out characteristics of induced versus natural activities. We obtain high-resolution earthquake location using improved S-wave picks, waveform cross-correlation and a new 3D velocity model. We then develop method to identify spatial-temporally isolated earthquake clusters. These clusters are classified into aftershock-type, swarm-type, and mixed-type (aftershock-like, with low skew, low magnitude and shorter duration), based on the relative timing of largest earthquakes and moment-release. The mixed-type clusters are mostly located at 3 - 4 km depth near injection well; while aftershock-type clusters and swarm-type clusters also occur further from injection well. By counting number of aftershocks within 1day following mainshock in each cluster, we find that the mixed-type clusters have much higher aftershock productivity compared with other types and historic M4 earthquakes. We analyze detailed spatial variation of 'b-value'. We find that the mixed-type clusters are mostly located within high b-value patches, while large (M>3) earthquakes and other types of clusters are located within low b-value patches. We are currently processing P and S-wave spectra to analyze the spatial-temporal correlation of earthquake stress parameter and seismicity characteristics. Preliminary results suggest that the

  13. Report to the Legislature on the California Energy Commission's Geothermal Development Grant Program for Local Governments

    SciTech Connect

    Not Available

    1983-04-01

    This report documents the California Energy Commission's administration of its Geothermal Development Grant Program for Local Governments. The Energy Commission established this program as a result of the passage of Assembly Bill 1905 (Bosco) in 1980. This legislation established the mechanism to distribute the state's share of revenues received from the leasing of federal mineral reserves for geothermal development. The federal government deposits these revenues in the Geothermal Resources Development Account (GRDA) created by AB 1905. The state allocates funds from the GRDA to the California Parklands and Renewable Resources Investment Fund, the counties of origin where the federal leases are located, and the Energy Commission. The legislation further directs the Energy Commission to disburse its share as grants to local governments to assist with the planning and development of geothermal resources. Activities which are eligible for funding under the Energy Commission's grant program include resource development projects, planning and feasibility studies, and activities to mitigate the impacts of existing geothermal development.

  14. Preliminary investigation of scale formation and fluid chemistry at the Dixie Valley Geothermal Field, Nevada

    SciTech Connect

    Bruton, C.J.; Counce, D.; Bergfeld, D.; Goff, F.; Johnson, S.D.; Moore, J.N.; Nimz, G.

    1997-06-27

    The chemistry of geothermal, production, and injection fluids at the Dixie Valley Geothermal Field, Nevada, was characterized to address an ongoing scaling problem and to evaluate the effects of reinjection into the reservoir. Fluids generally followed mixing-dilution trends. Recharge to the Dixie Valley system apparently originates from local sources. The low-pressure brine and injection waters were saturated with respect to amorphous silica, which correlated with the ongoing scaling problem. Local shallow ground water contains about 15% geothermal brine mixed with regional recharge. The elevated Ca, Mg, and HCO{sub 3} content of this water suggests that carbonate precipitation may occur if shallow groundwater is reinjected. Downhole reservoir fluids are close to equilibrium with the latest vein mineral assemblage of wairakite-epidote-quartz-calcite. Reinjection of spent geothermal brine is predicted to affect the region near the wellbore differently than it does the region farther away.

  15. 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.

  16. 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.

  17. Reservoir engineering applications for development and exploitation of geothermal fields in the Philippines

    SciTech Connect

    Vasquez, N.C.; Sarmiento, Z.F.

    1986-07-01

    After a geothermal well is completed, several tests and downhole measurements are conducted to help evaluate the subsurface fluid and reservoir properties intersected. From these tests, a conceptual model of the well can be developed by integrating data from the various parts of the field. This paper presents the completion techniques applied in geothermal wells, as well as the role of reservoir engineering science in delineating a field for development. Monitoring techniques and other reservoir engineering aspects of a field under exploitation are also discussed, with examples from the Philippines.

  18. Effect of Climate Change on Shallow Geothermal Energy Utilization

    NASA Astrophysics Data System (ADS)

    Park, B. H.; Ha, S. W.; Lee, S. Y.; Kim, H. S.; Lee, K. K.

    2014-12-01

    Climate change resulting from the increase of greenhouse gases became a global agenda, also it is an important issue in our daily life in many aspects. It was reported that the average ambient temperature of Korea has been increased by about 1.5℃ for the last 100 years. This pattern of climate change will also influence on the shallow geothermal energy utilization for space heating and cooling. In this study, degree days concept was used to estimate the heat demand according to the outside temperature variation. The calculated degree days were compared to the electricity consumption of ground source heat pump (GSHP) system in the study area. The results showed that there is a high correlation between the electricity consumption and degree days. Based upon such relationship, heating and cooling degree days were calculated using the future weather files from Representative Concentration Pathway (RCP) scenarios. RCPs mean four greenhouse gas concentration trajectories adopted by the IPCC for its fifth Assessment Report (AR5). Therefore, the resulted degree days will show the variations in heating and cooling demand and their durations according to the future anthropogenic greenhouse gas (GHG) emissions. Keywords : Climate Change, Geothermal Energy, Degree Days, Heat Demand

  19. Utilization of geothermal energy in a biomass-ethanol plant

    SciTech Connect

    Bottomley, J.

    1980-12-01

    A study has been done on the uses of geothermal fluid in the processing of ethanol from wood and fodder beet. From a technical viewpoint, geothermal heat has large scale uses in the preheating, hydrolysis, and distillation stages. It is possible that heat exchangers would not be necessary as direct use of geothermal fluid could be viable. The financial advantages however are not conclusive assuming a geothermal steam and water cost of $2.50/ton.

  20. Design and Implementation of Geothermal Energy Systems at West Chester University

    SciTech Connect

    Greg Cuprak

    2011-08-31

    West Chester University is launching a comprehensive transformation of its campus heating and cooling systems from traditional fossil fuels (coal, oil and natural gas) to geothermal. This change will significantly decrease the institution's carbon footprint and serve as a national model for green campus efforts. The institution is in the process of designing and implementing this project to build well fields, a pumping station and install connecting piping to provide the geothermal heat/cooling source for campus buildings. This project addresses the US Department of Energy Office of Energy Efficiency and Renewable Energy (EERE) goal to invest in clean energy technologies that strengthen the economy, protect the environment, and reduce dependence on foreign oil. In addition, this project advances EERE's efforts to establish geothermal energy as an economically competitive contributor to the US energy supply. For this grant, WCU will extend piping for its geo-exchange system. The work involves excavation of a trench approximately 8 feet wide and 10-12 feet deep located about 30 feet north of the curb along the north side of West Rosedale for a distance of approximately 1,300 feet. The trench will then turn north for the remaining distance (60 feet) to connect into the mechanical room in the basement of the Francis Harvey Green Library. This project will include crossing South Church Street near its intersection with West Rosedale, which will involve coordination with the Borough of West Chester. After installation of the piping, the trench will be backfilled and the surface restored to grass as it is now. Because the trench will run along a heavily-used portion of the campus, it will be accomplished in sections to minimize disruption to the campus as much as possible.

  1. Geothermal Program Review XV: proceedings. Role of Research in the Changing World of Energy Supply

    SciTech Connect

    1997-01-01

    The U.S. Department of Energy`s Office of Geothermal Technologies conducted its annual Program Review XV in Berkeley, March 24-26, 1997. The geothermal community came together for an in-depth review of the federally-sponsored geothermal research and development program. This year`s theme focussed on {open_quotes}The Role of Research in the Changing World of Energy Supply.{close_quotes} This annual conference is designed to promote technology transfer by bringing together DOE-sponsored researchers; utility representatives; geothermal developers; equipment and service suppliers; representatives from local, state, and federal agencies; and others with an interest in geothermal energy. Separate abstracts have been indexed to the database for contributions to this conference.

  2. 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)

  3. 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.

  4. Geothermal Energy R&D Program Annual Progress Report for Fiscal Year 1992

    SciTech Connect

    1993-07-01

    Geothermal budget actual amounts are shown for FY 1989 -1992, broken down by about 15 categories. Here, the main Program categories are: Exploration Technology, Drilling Technology, Reservoir Technology, Conversion Technology (power plants and materials), Industry-Coupled Drilling, Drilling Applications, Reservoir Engineering Applications, Direct Heat, Geopressured Wells Operation, and Hot Dry Rock Research. Here the title--Industry-Coupled Drilling--covered case studies of the Coso, CA, and Dixie Valley, NV, fields, and the Long Valley Exploratory Well (which had started as a magma energy exploration project, but reported here as a hydrothermal prospect evaluation well). (DJE 2005)

  5. The utilization of geothermal energy in the Philippines

    NASA Astrophysics Data System (ADS)

    Rivero, L. U.

    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.

  6. An assessment of leadership in geothermal energy technology research and development

    SciTech Connect

    Bruch, V.L.

    1994-03-01

    Geothermal energy is one of the more promising renewable energy technologies because it is environmentally benign and, unlike most renewable energy sources, can provide base power. This report provides an assessment of the research and development (R&D) work underway in geothermal energy in the following countries: Denmark, France, Germany, Italy, Japan, Russia, and the United Kingdom. While the R&D work underway in the US exceeds the R&D efforts of the other countries, the lead is eroding. This erosion is due to reductions in federal government funding for geothermal energy R&D and the decline of the US petroleum industry. This erosion of R&D leadership is hindering commercialization of US geothermal energy products and services. In comparison, the study countries are promoting the commercialization of their geothermal energy products and services. As a result, some of these countries, in particular Japan, will probably have the largest share of the global market for geothermal energy products and services; these products and services being targeted toward the developing countries (the largest market for geothermal energy).

  7. Session: Geopressured-Geothermal

    SciTech Connect

    Jelacic, Allan J.; Eaton, Ben A.; Shook, G. Michael; Birkinshaw, Kelly; Negus-de Wys, Jane

    1992-01-01

    This session at the Geothermal Energy Program Review X: Geothermal Energy and the Utility Market consisted of five presentations: ''Overview of Geopressured-Geothermal'' by Allan J. Jelacic; ''Geothermal Well Operations and Automation in a Competitive Market'' by Ben A. Eaton; ''Reservoir Modeling and Prediction at Pleasant Bayou Geopressured-Geothermal Reservoir'' by G. Michael Shook; ''Survey of California Geopressured-Geothermal'' by Kelly Birkinshaw; and ''Technology Transfer, Reaching the Market for Geopressured-Geothermal Resources'' by Jane Negus-de Wys.

  8. 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.

  9. Injection-driven restoration of the Beowawe geothermal field

    SciTech Connect

    Benoit, D.

    1997-12-31

    An initial strategy of injecting spent brine largely outside of the Beowawe reservoir caused the reservoir pressure to decline by 110 psi during the first year of plant operation. This decline allowed cold ground water, which was not separated from the geothermal water by any continuous barrier, to flow into and cool the geothermal reservoir. The drilling of a large new production well temporarily restored full plant output but accelerated the reservoir pressure and power plant output declines. After shifting injection directly back into the reservoir the reservoir pressure rapidly increased. This immediately improved the plant output as individual well outputs increased. Reservoir cooling continued unabated for approximately the next two years followed by a sharp reduction in the rate of temperature decline. The change in injection strategy reduced the gross megawatt decline rate of the power plant from 2.66 MW/yr to about 0.4 MW/yr.

  10. Seismic discrimination of a geothermal field: Cerro Prieto

    SciTech Connect

    Blakeslee, S.

    1984-04-01

    Extensive reprocessing of a subset of the seismic reflection data from Cerro Prieto has been performed. The formations and faults identified in the resulting seismic profile were correlated to cross-sections constructed from well log data. The production region coincides with a zone of reflection attenuation. A detailed velocity analysis reveals a lid of high velocity events rimming the reflection attenuation zone. This may prove to be a valuable discriminant for locating a geothermal resource using seismic reflection data.

  11. Reservoir Simulation on the Cerro Prieto Geothermal Field: A Continuing Study

    SciTech Connect

    Castaneda, M.; Marquez, R.; Arellano, V.; Esquer, C.A.

    1983-12-15

    The Cerro Prieto geothermal field is a liquid-dominated geothermal reservoir of complex geological and hydrological structure. It is located at the southern end of the Salton-Mexicali trough which includes other geothermal anomalies as Heber and East Mesa. Although in 1973, the initial power plant installed capacity was 75 MW of electrical power, this amount increased to 180 MW in 1981 as field development continued. It is expected to have a generating capacity of 620 MW by the end of 1985, when two new plants will be completely in operation. Questions about field deliverability, reservoir life and ultimate recovery related to planned installations are being presently asked. Numerical modeling studies can give very valuable answers to these questions, even at the early stages in the development of a field. An effort to simulate the Cerro Prieto geothermal reservoir has been undergoing for almost two years. A joint project among Comision Federal de Electricidad (CFE), Instituto de Investigaciones Electricas (IIE) and Intercomp of Houstin, Texas, was created to perform reservoir engineering and simulation studies on this field. The final project objective is tosimulate the behavior of the old field region when production from additional wells located in the undeveloped field zones will be used for feeding the new power plants.

  12. Decreasing geothermal energy conversion costs with advanced materials

    SciTech Connect

    Kukacka, L.E.

    1988-03-01

    If the Geothermal Technology Division (GTD) is to meet its programmatic objectives in hydrothermal fluid production and energy conversion, it is essential that new materials of construction be available. Level III Program Objectives include (1) reducing the costs associated with lost circulation episodes by 30% by 1992, (2) reducing the costs of deep wells and directionally dried wells by 10% by 1992, (3) reducing well-cementing problems for typical hydrothermal wells by 20% by 1991, and (4) the development of a corrosion-resistant and low-fouling heat exchanger tube material costing no more than three times the cost of carbon steel tubes by 1991. The Brookhaven National Laboratory (BNL) materials program is focused on meeting these objectives. Currently, work is in progress on (1) high temperature chemical systems for lost circulation control, (2) advanced high temperature (300/sup 0/C), lightweight (approx. 1.1 g/cc), CO/sub 2/-resistant well cementing materials, (3) thermally conductive composites for heat exchanger tubing, and (4) ultra high temperature (600/sup 0/C) cements for magma wells. In addition, high temperature elastomer technology developed earlier in the program is being transferred for use in the Geothermal Drilling Organization programs on drill pipe protectors, rotating head seals, and blow-out preventors. Recent accomplishments and the current status of work in each subtask are summarized in the paper.

  13. Geothermal energy: opportunities for California commerce. Final report

    SciTech Connect

    Not Available

    1982-08-01

    This report provides a preliminary engineering and economic assessment of five direct use projects using low and moderate temperature geothermal resources. Each project site and end-use application was selected because each has a high potential for successful, near-term (2 to 5 years) commercial development. The report also includes an extensive bibliography, and reference and contact lists. The five projects are: Wendel Agricultural Complex, East Mesa Livestock Complex, East Mesa Vegetable Dehydration Facility, Calapatria Heating District and Bridgeport Heating District. The projects involve actual investors, resource owners, and operators with varying financial commitments for project development. For each project, an implementation plan is defined which identifies major barriers to development and methods to overcome them. All projects were determined to be potentially feasible. Three of the projects cascade heat from a small-scale electric generator to direct use applications. Small-scale electric generation technology (especially in the 0.5 to 3 MW range) has recently evolved to such a degree as to warrant serious consideration. These systems provide a year-round heating load and substantially improve the economic feasibility of most direct use energy projects using geothermal resources above 200/sup 0/F.

  14. Potential of utilization of geothermal energy in Arizona. Executive summary

    SciTech Connect

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

    1982-08-01

    Arizona is one of the fastest growing states in the United States. It is in the midst of the movement of the population of the United States from its cold regions to the warm Southwest. Being a hot, arid region, its electrical demand is nearly 50% higher in the peak hot summer months than that of the other seven months. The major uncertainty of utilizing geothermal energy in Arizona is that very little exploration and development have occurred to date. The potential is good, based on (a) the fact that there are over 3000 thermal wells in Arizona out of a total of about 30,000 shallow (less than 1000 ft) irrigation wells. In addition, there is much young volcanic rock in the State of Arizona. The combination of data from thermal wells, young volcanic rock, water geochemistry and other geological tools, indicate that there is a large geothermal resource throughout the southern half of the state. It is believed that most of this resource is in the range of 50/sup 0/C (122/sup 0/F) to 150/sup 0/C (302/sup 0/F), limiting its uses to direct heat utilization rather than for electric power generation.

  15. Ethiopian geothermal resources and their characteristics

    SciTech Connect

    Gebregziabher, Z.

    1997-12-31

    Ethiopia is considered to be one of the favored countries with respect to high geothermal energy potential. If there is the possibility of exploiting the geothermal resource for direct use and electric energy generation, it can play an important role for the development of the country. Geothermal exploration in Ethiopia dates back to 1969. The country is currently using hydro and thermal plants as electric energy source. The proven geothermal fields, Langano and Tendaho may provide access for the utilization of the geothermal energy for electricity generation in the future. A geothermal power plant with a capacity of about 7 Mwe is expected to be on operation at Aluto Langano in the year 1998. In this paper the geothermal resources and the development problems in Ethiopia are discussed briefly.

  16. The Potential of Geothermal as a Major Supplier of U.S. Primary Energy using EGS technology

    NASA Astrophysics Data System (ADS)

    Tester, J. W.

    2012-12-01

    Recent national focus on the value of increasing our supply of indigenous, renewable energy underscores the need for re-evaluating all alternatives, particularly those that are large and well-distributed nationally. To transition from our current hydrocarbon-based energy system, we will need to expand and diversify the portfolio of options we currently have. One such option that has been undervalued and often ignored completely in national assessments is geothermal energy from both conventional hydrothermal resources and enhanced or engineered geothermal systems (EGS). Although geothermal energy is currently used for both electric and non-electric applications worldwide from conventional hydrothermal resources and in groundsource heat pumps, most of the emphasis in the US has been generating electricity. For example, a 2006 MIT-led study focused on the potential for EGS to provide 100,000 MWe of base-load electric generating capacity in the US by 2050. Since that time, a Cornell-led study has evaluated the potential for geothermal to meet the more than 25 EJ per year demand in the US for low temperature thermal energy for heating and other direct process applications Field testing of EGS in the US, Europe, and Australia is reviewed to outline what remains to be done for large-scale deployment. Research, Development and Demonstration (RD&D) needs in five areas important to geothermal deployment on a national scale will be reviewed: 1. Resource - estimating the magnitude and distribution of the US resource 2. Reservoir Technology - establishing requirements for extracting and utilizing energy from EGS reservoirs including drilling, reservoir design and stimulation 3. Utilization - exploring end use options for district heating, electricity generation and co-generation. 4. Environmental impacts and tradeoffs -- dealing with water and land use and seismic risk and quantifying the reduction in carbon emissions with increased deployment 5. Economics - projecting costs

  17. Temporal Variability in Seismic Velocity at the Salton Sea Geothermal Field

    NASA Astrophysics Data System (ADS)

    Taira, T.; Nayak, A.; Brenguier, F.

    2015-12-01

    We characterize the temporal variability of ambient noise wavefield and search for velocity changes associated with activities of the geothermal energy development at the Salton Sea Geothermal Field. The noise cross-correlations (NCFs) are computed for ~6 years of continuous three-component seismic data (December 2007 through January 2014) collected at 8 sites from the CalEnergy Subnetwork (EN network) with MSNoise software (Lecocq et al., 2014, SRL). All seismic data are downloaded from the Southern California Earthquake Data Center. Velocity changes (dv/v) are obtained by measuring time delay between 5-day stacks of NCFs and the reference NCF (average over the entire 6 year period). The time history of dv/v is determined by averaging dv/v measurements over all station/channel pairs (252 combinations). Our preliminary dv/v measurement suggests a gradual increase in dv/v over the 6-year period in a frequency range of 0.5-8.0 Hz. The resultant increase rate of velocity is about 0.01%/year. We also explore the frequency-dependent velocity change at the 5 different frequency bands (0.5-2.0 Hz, 0.75-3.0 Hz, 1.0-4.0 Hz, 1.5-6.0 Hz, and 2.0-8.0 Hz) and find that the level of this long-term dv/v variability is increased with increase of frequency (i.e., the highest increase rate of ~0.15%/year at the 0.5-2.0 Hz band). This result suggests that the velocity changes were mostly occurred in a depth of ~500 m assuming that the coda parts of NCFs (~10-40 s depending on station distances) are predominantly composed of scattered surface waves, with the SoCal velocity model (Dreger and Helmberger, 1993, JGR). No clear seasonal variation of dv/v is observed in the frequency band of 0.5-8.0 Hz.

  18. 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

  19. 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

  20. Using geothermal energy to heat a portion of a formation for an in situ heat treatment process

    DOEpatents

    Pieterson, Roelof; Boyles, Joseph Michael; Diebold, Peter Ulrich

    2010-06-08

    Methods of using geothermal energy to treat subsurface formations are described herein. Methods for using geothermal energy to treat a subsurface treatment area containing or proximate to hydrocarbons may include producing geothermally heated fluid from at least one subsurface region. Heat from at least a portion of the geothermally heated fluid may be transferred to the subsurface treatment area to heat the subsurface treatment area. At least some hydrocarbon fluids may be produced from the formation.

  1. Chemical Variations in the Rocks of La Primavera Geothermal Field (Mexico) Related with Hydrothermal Alteration

    SciTech Connect

    Prol-Ledesma, R.M.; Hernandez-Lombardini, S.I.; Lozano-Santa Cruz, R.

    1995-01-01

    The origin and fate of the components dissolved in the geothermal fluids are of great importance in the study of epithermal deposits, and in the environmental considerations for exploitation of geothermal fields. The chemical study of La Primavera geothermal field in Mexico has environmental importance due to the high arsenic concentration observed in the thermal water and the possible contamination of aquifers in the area. The variations in the chemistry of all altered samples with respect to unaltered samples indicates depletion of manganese, and the alkalis; and enrichment in iron and magnesium. Most samples show an enrichment in aluminum and titanium, and depletion in silica and calcium. Trace elements follow different trends at various depths: shallow depths are more favorable for deposition of the analyzed trace elements than the surface or the deep part of the reservoir.

  2. Efficient Use of Geothermal Energy in Spas - Call for Improvements

    NASA Astrophysics Data System (ADS)

    Straka, W.; Ponweiser, K.; Gollob, K.; Götzl, G.; Schneider, J. F.

    2009-04-01

    In Central Europe, the Pannonian Basin and adjacent areas are holding some of the most attractive geothermal energy resources available from subsurface hot water reservoirs. In fact, utilization of geothermal energy has a long-standing tradition in the region, mainly for thermal and medicinal bathing. Nevertheless, putting to use the extractable heat in a technical and economical optimum manner, and integrating the various energy flows (heating, cooling, vitiated air, etc.) in the application system as well as returning the cooled effluent (excluding used bath water) back to the reservoir, has not found general acceptance to date. This is regrettable not least because thermal spas can be regarded as virtually ideal objects for an integrated management of energy flows on a low temperature level. Hardly any other facilities are in nearly constant, year-round need of heat at a low temperature, as is actually delivered by most thermal aquifers. Also, waste heat and solar energy can be added without much inconvenience, and if hotels and/or therapeutic facilities are to be supplied, there will be cooling demand as well. Many spas in the region are about to update their technology. Complementing this development by an initiative for an integrated and therefore economical use of all the heat sinks and sources that may be present was the main objective of the "network project" PANTHERM (www.pantherm.eu) designed at the University of Applied Life Sciences and Natural Resources, Vienna, in cooperation with four Austrian and ten Hungarian, Slovak and Slovenian partners, and funded by the Austrian Research Promotion Agency, Vienna. In the course of a technical feasibility study it was dealt with the problem, and - by example of the spa of Sárvár in Hungary - demonstrated also, in which way the given mass and energy flows need to be interconnected in order to achieve an optimum energy yield, always with an eye on cost-effectiveness and sustainability. The other Eastern

  3. Geothermal Resource Reporting Metric (GRRM) Developed for the U.S. Department of Energy's Geothermal Technologies Office

    SciTech Connect

    Young, Katherine R.; Wall, Anna M.; Dobson, Patrick F.

    2015-09-02

    This paper reviews a methodology being developed for reporting geothermal resources and project progress. The goal is to provide the U.S. Department of Energy's (DOE) Geothermal Technologies Office (GTO) with a consistent and comprehensible means of evaluating the impacts of its funding programs. This framework will allow the GTO to assess the effectiveness of research, development, and deployment (RD&D) funding, prioritize funding requests, and demonstrate the value of RD&D programs to the U.S. Congress and the public. Standards and reporting codes used in other countries and energy sectors provide guidance to develop the relevant geothermal methodology, but industry feedback and our analysis suggest that the existing models have drawbacks that should be addressed. In order to formulate a comprehensive metric for use by the GTO, we analyzed existing resource assessments and reporting methodologies for the geothermal, mining, and oil and gas industries, and sought input from industry, investors, academia, national labs, and other government agencies. Using this background research as a guide, we describe a methodology for evaluating and reporting on GTO funding according to resource grade (geological, technical and socio-economic) and project progress. This methodology would allow GTO to target funding, measure impact by monitoring the progression of projects, or assess geological potential of targeted areas for development.

  4. Analysis of Injection-Induced Micro-Earthquakes in a Geothermal Steam Reservoir, The Geysers Geothermal Field, California

    SciTech Connect

    Rutqvist, Jonny; Rutqvist, J.; Oldenburg, C.M.

    2008-05-15

    In this study we analyze relative contributions to the cause and mechanism of injection-induced micro-earthquakes (MEQs) at The Geysers geothermal field, California. We estimated the potential for inducing seismicity by coupled thermal-hydrological-mechanical analysis of the geothermal steam production and cold water injection to calculate changes in stress (in time and space) and investigated if those changes could induce a rock mechanical failure and associated MEQs. An important aspect of the analysis is the concept of a rock mass that is critically stressed for shear failure. This means that shear stress in the region is near the rock-mass frictional strength, and therefore very small perturbations of the stress field can trigger an MEQ. Our analysis shows that the most important cause for injection-induced MEQs at The Geysers is cooling and associated thermal-elastic shrinkage of the rock around the injected fluid that changes the stress state in such a way that mechanical failure and seismicity can be induced. Specifically, the cooling shrinkage results in unloading and associated loss of shear strength in critically shear-stressed fractures, which are then reactivated. Thus, our analysis shows that cooling-induced shear slip along fractures is the dominant mechanism of injection-induced MEQs at The Geysers.

  5. A New Concept for Geothermal Energy Extraction: The Radiator - Enhanced Geothermal System

    NASA Astrophysics Data System (ADS)

    Hilpert, M.; Geiser, P.; Marsh, B. D.; Malin, P. E.; Moore, S.

    2014-12-01

    Enhanced Geothermal Systems (EGS) in hot dry rock frequently underperform or fail due to insufficient reservoir characterization and poorly controlled permeability stimulation. Our new EGS design is based on the concept of a cooling radiator of an internal combustion engine, which we call the Radiator EGS (RAD-EGS). Within a hot sedimentary aquifer, we propose to construct vertically extensive heat exchanger vanes, which consist of rubblized zones of high permeability and which emulate a hydrothermal system. A "crows-foot" lateral drilling pattern at multiple levels is used to form a vertical array that includes S1 and Shmax. To create the radiator, we propose to use propellant fracing. System cool-down is delayed by regional background flow and induced upward flow of the coolant which initially heats the rock. Tomographic Fracture Imaging is used to image and control the permeability field changes. Preliminary heat transfer calculations suggest that the RAD-EGS will allow for commercial electricity production for at least several tens of years.

  6. Aluto-Langano geothermal field, Ethiopian Rift Valley: Physical characteristics and the effects of gas on well performance

    SciTech Connect

    Gizaw, B. )

    1993-04-01

    This study, which focuses on the Aluto-Langano geothermal field, is part of the ongoing investigation of the geothermal systems in the Ethiopian Rift Valley. Aluto-Langano is a water-dominated gas-rich geothermal field, with a maximum temperature close to 360[degree]C, in the Lakes District region of the Ethiopian Rift Valley. The upflow zone for the system lies along a deep, young NNE trending fault and is characterized by boiling. As a result, the deep upflow zone loses some water as steam and produces a cooler saline shallow aquifer. The high partial pressure of carbon dioxide (about 30 bar in the reservoir) depresses the water table and restricts boiling to deeper levels. The main aquifer for the systems is in the Tertiary ignimbrite, which lies below 1400 m. The capacity of the existing wells is close to 7 MW[sub c]: the energy potential of the area is estimated to be between 3000 and 6000 MW[sub t] yr/km[sup 3], or 10-20 MW[sub c]/km[sup 3] for over 30 years.

  7. Design of a small fruit drier using geothermal energy

    SciTech Connect

    Lund, J.W.

    1996-02-01

    A fruit drier was originally proposed for a project at the Los Azufres geothermal field in Mexico. Since the drier was to be used in a demonstration project to interest local fruit growers and processors, the size was minimal to expedite construction and minimize cost. The design was based on preliminary work reported by Herman Guillen. The design is described here, as it can be adapted to many small or experimental situations. The actual design will handle about 900 kg (2000 lbs) of fruit (wet) per drying cycle. Cutting, storing and packaging of the fruit should be done on site in a separate building. A cold-storage facility may be designed to keep fresh fruit when harvest exceeds the capacity of the drier.

  8. Hyperspectral Thermal Infrared Analysis of the Salton Sea, CA Geothermal Field

    NASA Astrophysics Data System (ADS)

    Reath, K. A.; Ramsey, M. S.

    2011-12-01

    The Salton Sea Geothermal Field is an active 20 km2 region in southern California, which lies along the Calipatria Fault; an offshoot of the San Andreas Fault. Several geothermal fields (including the Davis-Schrimpf and Sandbar fields) and ten power plants generating 340 MW lie within this region. In order to better understand the mineral and thermal distribution of the surface, hyperspectral thermal infrared (TIR) data were acquired by Aerospace Corporation using the Spatially Enhanced Broadband Array Spectrograph System (SEABSS) airborne sensor on March 26, 2009 and April 6, 2010. SEBASS collects 128 wavelength channels at 1 meter spatial resolution, from which a new and more accurate interpretation was produced of the surface mineralogy of the geothermal fields and surrounding areas. Such data are rarely available for this type of scientific analysis and enabled the identification of mineral assemblages associated with geothermally-active areas. These minerals include anhydrite, gypsum, as well as an unknown mineral with a unique TIR wavelength feature at 8.2 μm. Comparing the 2009 and 2010 data, this unknown mineral varies in abundance and spatial distribution likely due to changes in rainfall. Samples rich in this mineral were collected from an area identified in the SEBASS data and analyzed in the laboratory using high resolution TIR emission spectroscopy. The same spectral absorption feature was found confirming the mineral's presence. Scanning electron microscopy (SEM) and x-ray diffraction (XRD) were performed on one of the samples in order to positively identify this mineral and further constrain the TIR analysis. By using the combination of airborne and laboratory spectroscopy, detailed and temporally-variable patterns of the surface mineralogy were ultimately produced. This work has the potential to be used at other geothermal sites to better characterize transient mineralogy, understand the influence of surface and ground water in these systems, and

  9. Thermal modeling of step-out targets at the Soda Lake geothermal field, Churchill County, Nevada

    NASA Astrophysics Data System (ADS)

    Dingwall, Ryan Kenneth

    Temperature data at the Soda Lake geothermal field in the southeastern Carson Sink, Nevada, highlight an intense thermal anomaly. The geothermal field produces roughly 11 MWe from two power producing facilities which are rated to 23 MWe. The low output is attributed to the inability to locate and produce sufficient volumes of fluid at adequate temperature. Additionally, the current producing area has experienced declining production temperatures over its 40 year history. Two step-out targets adjacent to the main field have been identified that have the potential to increase production and extend the life of the field. Though shallow temperatures in the two subsidiary areas are significantly less than those found within the main anomaly, measurements in deeper wells (>1,000 m) show that temperatures viable for utilization are present. High-pass filtering of the available complete Bouguer gravity data indicates that geothermal flow is present within the shallow sediments of the two subsidiary areas. Significant faulting is observed in the seismic data in both of the subsidiary areas. These structures are highlighted in the seismic similarity attribute calculated as part of this study. One possible conceptual model for the geothermal system(s) at the step-out targets indicated upflow along these faults from depth. In order to test this hypothesis, three-dimensional computer models were constructed in order to observe the temperatures that would result from geothermal flow along the observed fault planes. Results indicate that the observed faults are viable hosts for the geothermal system(s) in the step-out areas. Subsequently, these faults are proposed as targets for future exploration focus and step-out drilling.

  10. Assessment of the Appalachian Basin Geothermal Field: Combining Risk Factors to Inform Development of Low Temperature Projects

    NASA Astrophysics Data System (ADS)

    Smith, J. D.; Whealton, C.; Camp, E. R.; Horowitz, F.; Frone, Z. S.; Jordan, T. E.; Stedinger, J. R.

    2015-12-01

    Exploration methods for deep geothermal energy projects must primarily consider whether or not a location has favorable thermal resources. Even where the thermal field is favorable, other factors may impede project development and success. A combined analysis of these factors and their uncertainty is a strategy for moving geothermal energy proposals forward from the exploration phase at the scale of a basin to the scale of a project, and further to design of geothermal systems. For a Department of Energy Geothermal Play Fairway Analysis we assessed quality metrics, which we call risk factors, in the Appalachian Basin of New York, Pennsylvania, and West Virginia. These included 1) thermal field variability, 2) productivity of natural reservoirs from which to extract heat, 3) potential for induced seismicity, and 4) presence of thermal utilization centers. The thermal field was determined using a 1D heat flow model for 13,400 bottomhole temperatures (BHT) from oil and gas wells. Steps included the development of i) a set of corrections to BHT data and ii) depth models of conductivity stratigraphy at each borehole based on generalized stratigraphy that was verified for a select set of wells. Wells are control points in a spatial statistical analysis that resulted in maps of the predicted mean thermal field properties and of the standard error of the predicted mean. Seismic risk was analyzed by comparing earthquakes and stress orientations in the basin to gravity and magnetic potential field edges at depth. Major edges in the potential fields served as interpolation boundaries for the thermal maps (Figure 1). Natural reservoirs were identified from published studies, and productivity was determined based on the expected permeability and dimensions of each reservoir. Visualizing the natural reservoirs and population centers on a map of the thermal field communicates options for viable pilot sites and project designs (Figure 1). Furthermore, combining the four risk

  11. Geothermal energy environmental problems and control methods: review of recent findings

    SciTech Connect

    Nguyen, V.T.; Caskey, J.F.; Pfundstein, R.T.; Rifkin, S.B.

    1980-06-01

    The findings of a literature review on the environmental concerns and associated control methods of geothermal energy utilization are presented. The document introduces the environmental problems associated with geothermal energy utilization; assesses the current status of control methods; references appropriate environmental documents; and identifies areas where additional environmental research is needed. The review attempts to consolidate current understanding of the environmental impact of geothermal energy development. Approximately 180 reports written by authors in industry, government and academia have been reviewed in the areas of air emissions, surface and subsurface liquid discharges, solid wastes, noise, subsidence, and induced seismicity.

  12. 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.

  13. 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.

  14. Environmental assessmental, geothermal energy, Heber geothermal binary-cycle demonstration project: Imperial County, California

    SciTech Connect

    Not Available

    1980-10-01

    The proposed design, construction, and operation of a commercial-scale (45 MWe net) binary-cycle geothermal demonstration power plant are described using the liquid-dominated geothermal resource at Heber, Imperial County, California. The following are included in the environmental assessment: a description of the affected environment, potential environmental consequences of the proposed action, mitigation measures and monitoring plans, possible future developmental activities at the Heber anomaly, and regulations and permit requirements. (MHR)

  15. Measured ground-surface movements, Cerro Prieto geothermal field

    SciTech Connect

    Massey, B.L.

    1981-01-01

    The Cerro Prieto geothermal area in the Mexicali Valley, 30 kilometers southeast of Mexicali, Baja California, incurred slight deformation because of the extraction of hot water and steam, and probably, active tectonism. During 1977 to 1978, the US Geological Survey established and measured two networks of horizontal control in an effort to define both types of movement. These networks consisted of: (1) a regional trilateration net brought into the mountain ranges west of the geothermal area from stations on an existing US Geological Survey crustal-strain network north of the international border; and (2) a local net tied to stations in the regional net and encompassing the present and planned geothermal production area. Electronic distance measuring instruments were used to measure the distances between stations in both networks in 1978, 1979 and 1981. Lines in the regional net averaged 25 km. in length and the standard deviation of an individual measurement is estimated to be approx. 0.3 part per million of line length. The local network was measured using different instrumentation and techniques. The average line length was about 5 km. and the standard deviation of an individual measurement approached 3 parts per million per line length. Ground-surface movements in the regional net, as measured by both the 1979 and 1981 resurveys, were small and did not exceed the noise level. The 1979 resurvey of the local net showed an apparent movement of 2 to 3 centimeters inward toward the center of the production area. This apparent movement was restricted to the general limits of the production area. The 1981 resurvey of the local net did not show increased movement attributable to fluid extraction.

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

    SciTech Connect

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

    1980-08-01

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

  17. Analysis of requirements for accelerating the development of geothermal energy resources in California

    NASA Technical Reports Server (NTRS)

    Fredrickson, C. D.

    1978-01-01

    Various resource data are presented showing that geothermal energy has the potential of satisfying a singificant part of California's increasing energy needs. General factors slowing the development of geothermal energy in California are discussed and required actions to accelerate its progress are presented. Finally, scenarios for developing the most promising prospects in the state directed at timely on-line power are given. Specific actions required to realize each of these individual scenarios are identified.

  18. Advantage of incorporating geothermal energy into power-station cycles

    NASA Astrophysics Data System (ADS)

    White, A. A. L.

    1980-06-01

    The generation of electricity from low-temperature geothermal sources has been hampered by the low conversion efficiencies of Rankine cycle operating below 150 C. It is shown how the electrical output derived from a geothermal borehole may be substantially improved on that expected from these cycles by incorporating the geothermal heat into a conventional steam-cycle power station to provide feedwater heating. This technique can yield thermal conversion efficiencies of 11% which, for a well-head temperature of 100 C, is 50% greater than the output expected from a Rankine cycle. Coupled with the smaller capital costs involved, feedwater heating is thus a more attractive technique of converting heat into electricity. Although power stations above suitable geothermal resources would ideally have the geothermal heat incorporated from the design stage, experiments at Marchwood Power Station have shown that small existing sets can be modified to accept geothermal feedwater heating.

  19. 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.

  20. Federal Assistance Program Quarterly Project Progress Report. Geothermal Energy Program: Information Dissemination, Public Outreach, and Technical Analysis Activities. Reporting Period: January 1 - March 31, 2001 [Final report

    SciTech Connect

    Lund, John W.

    2002-03-22

    The final report of the accomplishments of the geothermal energy program: information dissemination, public outreach and technical analysis activities by the project team consisting of the Geo-Heat Center, Geothermal Resources Council, Geothermal Education Office, Geothermal Energy Association and the Washington State University Energy Program.

  1. Issue Paper Potential Water Availability Problems Associated with Geothermal Energy Operations

    SciTech Connect

    1982-02-19

    The report is the first to study and discuss the effect of water supply problems of geothermal development. Geothermal energy resources have the potential of making a significant contribution to the U.S. energy supply situation, especially at the regional and local levels where the resources are located. A significant issue of concern is the availability and cost of water for use in a geothermal power operation primarily because geothermal power plants require large quantities of water for cooling, sludge handling and the operation of environmental control systems. On a per unit basis, geothermal power plants, because of their inherent high heat rejection rates, have cooling requirements several times greater than the conventional fossil fuel plants and therefore the supply of water is a critical factor in the planning, designing, and siting of geothermal power plants. However, no studies have been specifically performed to identify the water requirements of geothermal power plants, the underlying causes of water availability problems, and available techniques to alleviate some of these problems. There is no cost data included in the report. The report includes some descriptions of known geothermal areas. [DJE-2005

  2. Microearthquake source mechanism studies at the Geysers geothermal field

    SciTech Connect

    Kirkpatrick, A.; Romero, A. Jr.; Peterson, J. Jr.; Johnson, L.; Majer, E.

    1996-04-01

    In this paper the authors discuss moment tensors obtained from inversion of MEQ waveform data recorded at the Southeast (SE) and Northwest (NW) Geysers geothermal areas by the high-resolution seismic networks operated by Lawrence Berkeley National Laboratory (Berkeley Lab) and the Coldwater Creek Geothermal Company (now CCPA). The network in the SE Geysers consists of 13 high-frequency (4.5 Hz), digital (480 samples), three-component, telemetered stations deployed on the surface in portions of the Calpine, Unocal-NEC-Thermal (U-N-T), and Northern California Power Agency (NCPA) leases. The network in the NW Geysers is a 16-station borehole array of three-component geophones (4.5 Hz), digital at 400 samples/sec, and telemetered to a central site. One of the main objectives of Berkeley Lab`s program at the Geysers is to assess the utility of MEQ monitoring as a reservoir management tool. Discrimination of the mechanisms of these events may aid in the interpretation of MEQ occurrence patterns and their significance to reservoir processes and conditions of interest to reservoir managers. Better understanding of the types of failure deduced from source mechanism studies, and their relations to production parameters, should also lead to a better understanding of the effects of injection and withdrawal.

  3. Pressure-interference testing of the Sumikawa geothermal field

    SciTech Connect

    Garg, S.K.; Pritchett, J.W.; Ariki, K.; Kawano, Y.

    1991-01-01

    Pressure interference tests have been used to determine the permeability structure of the Sumikawa reservoir. Interference tests between wells S-4 and KY-1 have indicated the presence of a very high permeability (140 md) north-south channel in the altered andesite layer. Pressure buildup data from well SN-7D have provided indications of a high transmissivity (kh {approx} 18 darcy-meters) reservoir located in the granodiorite layer, lack of pressure response in nearby shutin Sumikawa wells implies that the reservoir penetrated by SN-7D is isolated from the shallower reservoir in the altered andesites. The ''altered andesite'' and the ''granodiorite'' formations constitute the principal geothermal aquifers at Sumikawa. Pressure interference tests (wells KY-1 and SB-2, and wells KY-2 and SB-3) have also confirmed the presence of moderately high transmissivity ({approx} 2 darcy-meters) dacitic layers in the ''marine-volcanic complex'' formation. Because of its low vertical permeability, the ''marine volcanic complex'' formation constitutes an attractive target for the reinjection of waste geothermal fluids.

  4. Long-term Evolution of Seismicity Rates in California Geothermal Fields

    NASA Astrophysics Data System (ADS)

    Trugman, D. T.; Shearer, P. M.; Borsa, A. A.; Fialko, Y. A.

    2015-12-01

    The temporal evolution of seismicity rates within geothermal fields provides important observational constraints on the ways in which rocks respond to natural and anthropogenic loading. We develop an iterative, regularized inversion procedure to partition the observed seismicity rate into two primary components: (1) the interaction seismicity rate due to earthquake-earthquake triggering, and (2) the time-varying background seismicity rate controlled by other time-dependent stresses, including anthropogenic forcing. We parameterize our seismicity model using an Epidemic-Type Aftershock Sequence (ETAS) framework with a background seismicity rate that varies smoothly with time. We apply our methodology to study long-term changes in seismicity rates at the Geysers and Salton Sea geothermal fields in California. At the Geysers, we find that the background seismicity rate is highly correlated with fluid injection. Seismicity at the Geysers has experienced a rate increase of approximately 50% since year 2000 and exhibits strong seasonal fluctuations, both of which can be explained by changes in fluid injection following the completion of the Santa Rosa pipeline. At the Salton Sea, the background seismicity rate has remained relatively stable since 1990, with short-term fluctuations that are not obviously modulated by fluid fluxes related to the operation of the geothermal field. The differences in the field-wide seismicity responses of the Geysers and Salton Sea to geothermal plant operation may reflect differences in in-situ reservoir conditions and local tectonics, indicating that induced seismicity may not be solely a function of fluid injection and withdrawal.

  5. Compilation of Rare Earth Element Analyses from US Geothermal Fields and Mid Ocean Ridge Hydrothermal Vents

    DOE Data Explorer

    Andrew Fowler

    2015-10-01

    Compilation of rare earth element and associated major and minor dissolved constituent analytical data for USA geothermal fields and global seafloor hydrothermal vents. Data is in original units. Reference to and use of this data should be attributed to the original authors and publications according to the provisions outlined therein.

  6. Workshop on CSDP data needs for the BACA geothermal field: a summary

    SciTech Connect

    Mangold, D.C.; Tsang, C.F.

    1984-06-01

    These workshop summaries discuss the data needs of the Continental Scientific Drilling Program (CSDP) community and provide an introduction to the available geological, geophysical, geochemical and reservoir engineering data of the Baca geothermal field, Valles Caldera, New Mexico. Individual abstracts have been prepared for the presentations. (ACR)

  7. Summary of recent progress in understanding the Cerro Prieto Geothermal Field, Baja, California, Mexico

    SciTech Connect

    Lippmann, M.J.; Witherspoon, P.A.

    1980-07-01

    Geological and geophysical studies indicate that the Cerro Prieto reservoir is quite heterogeneous due to complex lithofacies fault structures, and hydrothermal alteration. Geochemical investigations have provided clues on the origin of the geothermal fluids, their recharge paths and on the reservoir processes accompanying the exploitation of the field. Well tests have yielded information on the permeability of the reservoir. (MHR)

  8. Geochemistry of igneous rocks from the Cerro Prieto geothermal field, northern Baja California, Mexico

    NASA Astrophysics Data System (ADS)

    Herzig, C. T.

    1990-08-01

    Fractional crystallization of basaltic magma, derived from an oceanic affinity source region present beneath the Salton Trough and emplaced into a pull-apart basin of this continental rift regime, produced a tholeiitic suite of hypabyssal rocks consisting of basalt, andesite and dacite within the Cerro Prieto geothermal field, located in northern Baja California, Mexico. Higher light-rare-earth-element abundances for a basalt from the Cerro Prieto geothermal field in comparison to basalts from the Gulf of California and the East Pacific Rise suggest partial assimilation of crustal materials into the parental magmas generated beneath the Salton Trough. The crustal contaminant may be present near the surface today in the form of granitoids of the Peninsular Ranges batholith, at deeper levels as hydrothermally altered materials near the base of the Salton Trough, or may be a relict feature of Tertiary subduction contained within the upper mantle beneath the Salton Trough. The Sr isotopic compositions of dacites from the nearby Cerro Prieto volcano range from 0.7029 to 0.7036, indicating an oceanic affinity source for these rocks. The suite of hypabyssal rocks of tholeiitic affinity present within the Cerro Prieto geothermal field, related by fractional crystallization, link the dacite volcano of Cerro Prieto to gabbroic plutons inferred to exist beneath the Cerro Prieto geothermal field.

  9. Oregon: a guide to geothermal energy development. [Includes glossary

    SciTech Connect

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

    1980-06-01

    The following subjects are covered: Oregons' geothermal potential, exploration methods and costs, drilling, utilization methods, economic factors of direct use projects, and legal and institutional setting. (MHR)

  10. Geothermal exploration in a cost-competitive international energy market

    SciTech Connect

    Combs, J.

    1997-12-31

    The cost of exploration for, and confirmation of, an economic geothermal reservoir can be reduced by at least fifty percent (50%) with the use of diagnostic exploration surveys and slimhole technology. Although many technical papers and text-books on geothermal exploration have been published during the past twenty-five years, the goal of the present paper is to present the elements of a cost effective exploration paradigm for the identification, delineation and verification of economically viable geothermal reservoirs. The high cost of drilling large-diameter geothermal wells will usually justify the use, on a given prospect, of basically all of the exploration tools that will be discussed. Furthermore, with the use of slim holes in geothermal exploration to identify and evaluate the productive capacity of the geothermal reservoir, the high cost of large-diameter exploration wells will also be eliminated. However, in nearly every case, the cost of geothermal exploration represents a minor share of the total geothermal power project costs and the elimination of one non-productive geothermal well will almost always offset the exploration budget.

  11. Response of shallow geothermal energy pile from laboratory model tests

    NASA Astrophysics Data System (ADS)

    Marto, A.; Amaludin, A.

    2015-09-01

    In shallow geothermal energy pile systems, the thermal loads from the pile, transferred and stored in the soil will cause thermally induced settlement. This factor must be considered in the geotechnical design process to avoid unexpected hazards. Series of laboratory model tests were carried out to study the behaviour of energy piles installed in kaolin soil, subjected to thermal loads and a combination of axial and thermal loads (henceforth known as thermo-axial loads). Six tests which included two thermal load tests (35°C and 40°C) and four thermo-axial load tests (100 N and 200 N, combined with 35°C and 40°C thermal loads) were conducted. To simulate the behaviour of geothermal energy piles during its operation, the thermo-axial tests were carried out by applying an axial load to the model pile head, and a subsequent application of thermal load. The model soil was compacted at 90% maximum dry density and had an undrained shear strength of 37 kPa, thus classified as having a firm soil consistency. The behaviour of model pile, having the ultimate load capacity of 460 N, was monitored using a linear variable displacement transducer, load cell and wire thermocouple, to measure the pile head settlement, applied axial load and model pile temperature. The acquired data from this study was used to define the thermo-axial response characteristics of the energy pile model. In this study, the limiting settlement was defined as 10% of the model pile diameter. For thermal load tests, higher thermal loads induced higher values of thermal settlement. At 40°C thermal load an irreversible settlement was observed after the heating and cooling cycle was applied to the model pile. Meanwhile, the pile response to thermo-axial loads were attributed to soil consistency and the magnitude of both the axial and thermal loads applied to the pile. The higher the thermoaxial loads, the higher the settlements occurred. A slight hazard on the model pile was detected, since the settlement

  12. Use of slim holes for reservoir evaluation at the Steamboat Hills Geothermal Field, Nevada, USA

    SciTech Connect

    Combs, Jim; Goranson, Colin

    1994-01-20

    Three slim holes were drilled at the Steamboat Hills Geothermal Field in northwestern Nevada about 15 km south of Reno. The slim holes were drilled to investigate the geologic conditions, thermal regime and productive characteristics of the geothermal system. They were completed through a geologic sequence consisting of alluvium cemented by geothermal fluids, volcaniclastic materials, and granodiorite. Numerous fractures, mostly sealed, were encountered throughout the drilled depth; however, several open fractures in the granodiorite, dipping between 65 and 90{degree}, had apertures up to 13 mm in width. The depths of the slim holes vary from 262 to 277 m with open-hole diameters of 76 mm. Pressure and temperature logs gave bottom-hole temperatures ranging from 163 to 166{degree} C. During injection testing, downhole pressures were measured using capillary tubing with a surface quartz transducer while temperatures were measured with a Kuster temperature tool located below the capillary tubing pressure chamber. No pressure increase was measured at reservoir depths in any of the three slim holes while injecting 11 kg/s of 29{degree}C water indicating a very high permeability in the geothermal reservoir. These injection test results suggested that productive geothermal fluids could be found at depths sufficient for well pumping equipment and at temperatures needed for electrical power production using binary-type conversion technology.

  13. Geothermal energy program summary: Volume 2, Research summaries, fiscal year 1988

    SciTech Connect

    Not Available

    1989-03-01

    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. The Geothermal Energy Program Summary for Fiscal Year 1988 is a two-volume set designed to be an easily accessible reference to inform the US geothermal industry and other interested parties of the technological advances and progress achieved in the DOE geothermal program as well as to describe the thrust of the current R&D effort and future R&D directions. This volume, Volume II, 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. The Program Summary is intended as an important technology transfer vehicle to assure the wide and timely dissemination of information concerning the department`s geothermal research.

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

    SciTech Connect

    Nunz, G.J.

    1993-07-01

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

  15. Relevance of deep-subsurface microbiology for underground gas storage and geothermal energy production.

    PubMed

    Gniese, Claudia; Bombach, Petra; Rakoczy, Jana; Hoth, Nils; Schlömann, Michael; Richnow, Hans-Hermann; Krüger, Martin

    2014-01-01

    This chapter gives the reader an introduction into the microbiology of deep geological systems with a special focus on potential geobiotechnological applications and respective risk assessments. It has been known for decades that microbial activity is responsible for the degradation or conversion of hydrocarbons in oil, gas, and coal reservoirs. These processes occur in the absence of oxygen, a typical characteristic of such deep ecosystems. The understanding of the responsible microbial processes and their environmental regulation is not only of great scientific interest. It also has substantial economic and social relevance, inasmuch as these processes directly or indirectly affect the quantity and quality of the stored oil or gas. As outlined in the following chapter, in addition to the conventional hydrocarbons, new interest in such deep subsurface systems is rising for different technological developments. These are introduced together with related geomicrobiological topics. The capture and long-termed storage of large amounts of carbon dioxide, carbon capture and storage (CCS), for example, in depleted oil and gas reservoirs, is considered to be an important options to mitigate greenhouse gas emissions and global warming. On the other hand, the increasing contribution of energy from natural and renewable sources, such as wind, solar, geothermal energy, or biogas production leads to an increasing interest in underground storage of renewable energies. Energy carriers, that is, biogas, methane, or hydrogen, are often produced in a nonconstant manner and renewable energy may be produced at some distance from the place where it is needed. Therefore, storing the energy after its conversion to methane or hydrogen in porous reservoirs or salt caverns is extensively discussed. All these developments create new research fields and challenges for microbiologists and geobiotechnologists. As a basis for respective future work, we introduce the three major topics, that is

  16. Evaluation of geothermal energy in Arizona. Quarterly topical progress report, January 1, 1980-March 31, 1981

    SciTech Connect

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

    1981-03-31

    The tasks, objectives and completed work are discussed for the legislative and institutional program, cities program, geothermal applications utilization technology, and outreach. The work on the Maryvale Terrace development and the New Mexico Energy Institute are described. (MHR)

  17. Development of the Geothermal Heat Pump Market in China; Renewable Energy in China

    SciTech Connect

    Not Available

    2006-03-01

    This case study is one in a series of Success Stories on developing renewable energy technologies in China for a business audience. It focuses on the development of the geothermal heat pump market in China.

  18. 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.

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

    SciTech Connect

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

    1989-07-01

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

  20. Initial Measurements of Petrophysical Properties on Rocks from the Los Azufres, Mexico, Geothermal Field

    SciTech Connect

    Contreras, E.; Iglesias, E.; Razo, E.

    1986-01-21

    Petrophysical properties of geothermal reservoir rocks are valuable information for many activities, including reservoir characterization, modeling, field test analysis and planning of exploitation techniques. Petrophysical data of rocks from geothermal reservoirs located in volcanic areas is in general very scarce. In particular, no petrophysical data of rocks from the Los Azufres geothermal field area has ever been published. This work presents the results of initial petrophysical studies on outcrop rocks and drill core samples from the Los Azufres geothermal field. These studies are the first part of an ongoing experimental program intended to establish a data-base about physical properties of the Los Azufres rocks, in support of the many reservoir engineering activities which require of such information. The experimental work carried out consisted of laboratory measurements of density, porosity, permeability, compressibility, thermal conductivity, thermal expansion, electrical resistivity and sonic wave velocities. Some of the experiments were aimed at investigation of the effects of temperature, pressure, saturation and other parameters on the physical properties of rocks.

  1. 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

  2. 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.

  3. Response of the Los Azufres Geothermal Field to Four Years of 25 MW Wellhead Generation

    SciTech Connect

    Kruger, P.; Ortiz, J.; Miranda, G.; Gallardo, M.

    1987-01-20

    Production and chemical data have been compiled and analyzed on a six-month averaged basis for the first four years of electric energy generation with five 5-MW wellhead generators at the Los Azufres geothermal field. The data were evaluated with respect to the extent of observable thermal drawdown of the reservoir from 25 MW of generation in relation to the estimated capacity of the field of several hundred megawatts of power. The analysis updates the previous one compiled after the first two years of continuous production, at which time the results indicated that differences in reservoir temperature estimated from geochemical thermometers and wellhead production data were not statistically significant based on the number of data and the standard deviations. Analysis of the data after four years of operation were made for the larger number of data and smaller standard deviations. The results review the adequacy of the sampling frequency and the reliability of the measurements from statistical t-Test of the means of the first and second two-year periods. 3 figs., 5 tabs., 20 refs.

  4. Preliminary estimation of the reservoir capacity and the longevity of the Baca Geothermal Field, New Mexico

    SciTech Connect

    Bodvarsson, G.S.; Vonder Haar, S.; Wilt, M.; Tsang, C.F.

    1980-07-01

    A 50 MW geothermal power plant is currently under development at the Baca site in the Valles Caldera, New Mexico, as a joint venture of the Department of Energy (DOE), Union Oil Company of California, and the Public Service Company of New Mexico (PNM). To date, over 20 wells have been drilled on the prospect, and the data from these wells indicate the presence of a high-temperature liquid dominated reservoir. Data from open literature on the field are used to estimate the amount of hot water in place (reservoir capacity) and the length of time the reservoir can supply steam for a 50 MW power plant (reservoir longevity). The reservoir capacity is estimated by volumetric calculations using existing geological, geophysical, and well data. The criteria used are described and the sensitivity of the results discussed. The longevity of the field is studied using a two-phase numerical simulator (SHAFT79). A number of cases are studied based upon different boundary conditions, and injection and production criteria. Constant or variable mass production is employed in the simulations with closed, semi-infinite or infinite reservoir boundaries. In one of the cases, a fault zone feeding the production region is modeled. The injection strategy depends on the available waste water. The results of these simulations are discussed and the sensitivity of the results, with respect to mesh size and the relative permeability curves used, are briefly studied.

  5. Geological control on the reservoir characteristics of Olkaria West Geothermal Field, Kenya

    SciTech Connect

    Omenda, Peter A.

    1994-01-20

    The reservoir of the West Olkaria Geothermal Field is hosted within tuffs and the reservoir fluid is characterized by higher concentrations of reservoir CO{sub 2} (10,000-100,000 mg/kg) but lower chloride concentrations of about 200 mg/kg than the East and North East Fields. The West Field is in the outflow and main recharge area of the Olkaria geothermal system. Permeability is generally low in the West Field and its distribution is strongly controlled by the structures. Fault zones show higher permeability with wells drilled within the structures havin larger total mass outputs. However, N-S and NW-SE faults are mainly channels for cold water downflow into the reservoir. Well feeder zones occur mostly at lava-tuff contacts; within fractured lava flows and at the contacts of intrusives and host rocks.

  6. Open Questions on the Origin of Life at Anoxic Geothermal Fields

    PubMed Central

    Mulkidjanian, Armen Y.; Bychkov, Andrew Yu.; Dibrova, Daria V.; Galperin, Michael Y.; Koonin, Eugene V.

    2014-01-01

    We have recently reconstructed the ‘hatcheries’ of the first cells by combining geochemical analysis with phylogenomic scrutiny of the inorganic ion requirements of universal components of modern cells (Mulkidjanian et al.: Origin of first cells at terrestrial, anoxic geothermal fields. Proc Natl Acad Sci USA 2012, 109:E821–830). These ubiquitous, and by inference primordial, proteins and functional systems show affinity to and functional requirement for K+, Zn2+, Mn2+, and phosphate. Thus, protocells must have evolved in habitats with a high K+/Na+ ratio and relatively high concentrations of Zn, Mn and phosphorous compounds. Geochemical reconstruction shows that the ionic composition conducive to the origin of cells could not have existed in marine settings but is compatible with emissions of vapor-dominated zones of inland geothermal systems. Under anoxic, CO2-dominated atmosphere, the ionic composition of pools of cool, condensed vapor at anoxic geothermal fields would resemble the internal milieu of modern cells. Such pools would be lined with porous silicate minerals mixed with metal sulfides and enriched in K+ ions and phosphorous compounds. Here we address some questions that have appeared in print after the publication of our anoxic geothermal field scenario. We argue that anoxic geothermal fields, which were identified as likely cradles of life by using a top-down approach and phylogenomics analysis as a tool, could provide geochemical conditions similar to those which were suggested as most conducive for the emergence of life by the chemists who pursuit the complementary bottom-up strategy. PMID:23132762

  7. Vitrinite reflectance geothermometry and apparent heating duration in the Cerro Prieto geothermal field

    USGS Publications Warehouse

    Barker, C.E.; Elders, W.A.

    1981-01-01

    Vitrinite reflectance measured in immersion oil (Ro) on kerogen extracted from hydrothermally altered mudstones in borehole M-84 at the Cerro Prieto geothermal field exhibit an increase in mean reflectance (Ro) from 0.12 per cent at 0.24 km depth to 4.1 per cent at 1.7 km depth. Downhole temperatures measured over this interval increase from about 60?? to 340??C. These Ro data plotted against temperature fall along an exponential curve with a coefficient of determination of about 0.8. Other boreholes sampled in the field show similar relationships. A regression curve calculated for temperature and Ro in borehole M-105 correctly predicts temperatures in other boreholes within the central portion of the geothermal system. The correlation between the reflectance values and logged temperature, together with consistent temperature estimates from fluid inclusion and oxygen isotope geothermometry, indicates that changes in Ro are an accurate and sensitive recorder of the maximum temperature attained. Therefore, vitrinite reflectance can be used in this geothermal system to predict the undisturbed temperature in a geothermal borehole during drilling before it regains thermal equilibrium. Although existing theoretical functions which relate Ro to temperature and duration of heating are inaccurate, empirical temperature-Ro curves are still useful for geothermometry. A comparison of temperature-Ro regression curves derived from nine boreholes within the Cerro Prieto system suggests that heating across the central portion of the field occurred penecontemporaneously, but varies near margins. Boreholes M-93 and M-94 appear to have cooled from their maximum temperatures, whereas M-3 and Prian-1 have only recently been heated. Comparison of the temperature-Ro data from the Salton Sea, California, geothermal system indicates that the duration of heating has been longer there than at the Cerro Prieto field. ?? 1981.

  8. Joint operation and energy sales of the Indonesia`s geothermal development project

    SciTech Connect

    Suryadi, D.; Sulaiman, S.; Boedihardi, M.; Agus, I.

    1995-12-31

    The government of Indonesia plans to intensify the utilization of geothermal energy for electrical generation as part of its energy diversification policy. Presently only 1.6% of the 19,650 megawatts country-wide potential are being utilized. To accelerate the development of geothermal energy, the government invites private companies as Contractor to cooperate with PERTAMINA, the State Company that is authorized to explore and exploit oil, gas and geothermal reserves in Indonesia, in a form of Joint Operation Contract (JOC) and gives incentives in fiscal and other terms to contractors that develop this source of energy. In the JOC, PERTAMINA is responsible for the management of operation and Contractor is responsible for the execution of the operation. Contractor has to provide financial, technical assistance and all facilities required to conduct geothermal operation and carries the risks of operating cost and therefore has an economic interest from the project. Each party involved in the development has a right to demand a certain portion of the Net Operating Income (NOI). The Energy Sales Contract (ESC) is made in conjunction with the JOC whereby the buyer agrees to purchase from PERTAMINA geothermal steam or electricity which is generated from geothermal energy produced and delivered by Contractor to the buyer on behalf of PERTAMINA.

  9. Data assimilation for the investigation of deep temperature and geothermal energy in the Netherlands.

    NASA Astrophysics Data System (ADS)

    Bonté, Damien; Limberger, Jon; Lipsey, Lindsey; Cloetingh, Sierd; van Wees, Jan-Diederik

    2016-04-01

    Deep geothermal energy systems, mostly for the direct use of heat, have been attracting more and more interest in the past 10 years in Western Europe. In the Netherlands, where the sector took off with the first system in 2005, geothermal energy is seen has a key player for a sustainable future. To support the development of deep geothermal energy system, the scientific community has been working on tools that could be used to highlight area of potential interest for geothermal exploration. In the Netherlands, ThermoGIS is one such tool that has been developed to inform the general public, policy makers, and developers in the energy sector of the possibility of geothermal energy development. One major component incorporated in this tool is the temperature model. For the Netherlands, we created a thermal model at the lithospheric scale that focus on the sedimentary deposits for deep geothermal exploration. This regional thermal modelling concentrates on the variations of geological thermal conductivity and heat production both in the sediments and in the crust. In addition, we carried out special modelling in order to specifically understand convectivity in the basin, focusing on variations at a regional scale. These works, as well as recent improved of geological knowledge in the deeper part of the basin, show interesting evidence for geothermal energy development. At this scale, the aim of this work is to build on these models and, using data assimilation, to discriminate in the actual causes of the observed anomalies. The temperature results obtained for the Netherlands show some thermal patterns that relate to the variation of the thermal conductivity and the geometry of the sediments. There is also strong evidence to indicate that deep convective flows are responsible for thermal anomalies. The combination of conductive and local convective thermal patterns makes the deeper part of the Dutch sedimentary basin of great interest for the development of geothermal

  10. 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.

  11. A hybrid geothermal energy conversion technology: Auxiliary heating of geothermally preheated water or CO2 - a potential solution for low-temperature resources

    NASA Astrophysics Data System (ADS)

    Saar, Martin; Garapati, Nagasree; Adams, Benjamin; Randolph, Jimmy; Kuehn, Thomas

    2016-04-01

    Safe, sustainable, and economic development of deep geothermal resources, particularly in less favourable regions, often requires employment of unconventional geothermal energy extraction and utilization methods. Often "unconventional geothermal methods" is synonymously and solely used as meaning enhanced geothermal systems, where the permeability of hot, dry rock with naturally low permeability at greater depths (4-6 km), is enhanced. Here we present an alternative unconventional geothermal energy utilization approach that uses low-temperature regions that are shallower, thereby drastically reducing drilling costs. While not a pure geothermal energy system, this hybrid approach may enable utilization of geothermal energy in many regions worldwide that can otherwise not be used for geothermal electricity generation, thereby increasing the global geothermal resource base. Moreover, in some realizations of this hybrid approach that generate carbon dioxide (CO2), the technology may be combined with carbon dioxide capture and storage (CCS) and CO2-based geothermal energy utilization, resulting in a high-efficiency (hybrid) geothermal power plant with a negative carbon footprint. Typically, low- to moderate-temperature geothermal resources are more effectively used for direct heat energy applications. However, due to high thermal losses during transport, direct use requires that the heat resource is located near the user. Alternatively, we show here that if such a low-temperature geothermal resource is combined with an additional or secondary energy resource, the power production is increased compared to the sum from two separate (geothermal and secondary fuel) power plants (DiPippo et al. 1978) and the thermal losses are minimized because the thermal energy is utilized where it is produced. Since Adams et al. (2015) found that using CO2 as a subsurface working fluid produces more net power than brine at low- to moderate-temperature geothermal resource conditions, we

  12. Geothermal energy technology: issues, R and D needs, and cooperative arrangements

    SciTech Connect

    Not Available

    1987-01-01

    In 1986, the National Research Council, through its Energy Engineering Board, formed the Committee on Geothermal Energy Technology. The committee's study addressed major issues in geothermal energy technology, made recommendations for research and development, and considered cooperative arrangements among government, industry, and universities to facilitate RandD under current severe budget constraints. The report addresses four types of geothermal energy: hydrothermal, geopressured, hot dry rock, and magma systems. Hydrothermal systems are the only type that are now economically competitive commercially. Further technology development by the Department of Energy could make the uneconomical hydrothermal resources commercially attractive to the industry. The economics are more uncertain for the longer-term technologies for extracting energy from geopressured, hot dry rock, and magma systems. For some sites, the cost of energy derived from geopressured and hot dry rock systems is projected within a commercially competitive range. The use of magma energy is too far in the future to make reasonable economic calculations.

  13. Elevated carbon dioxide flux at the Dixie Valley geothermal field, Nevada; relations between surface phenomena and the geothermal reservoir

    USGS Publications Warehouse

    Bergfeld, D.; Goff, F.; Janik, C.J.

    2001-01-01

    In the later part of the 1990s, a large die-off of desert shrubs occurred over an approximately 1 km2 area in the northwestern section of the Dixie Valley (DV) geothermal field. This paper reports results from accumulation-chamber measurements of soil CO2 flux from locations in the dead zone and stable isotope and chemical data on fluids from fumaroles, shallow wells, and geothermal production wells within and adjacent to the dead zone. A cumulative probability plot shows three types of flux sites within the dead zone: Locations with a normal background CO2 flux (7 g m-2 day-1); moderate flux sites displaying "excess" geothermal flux; and high flux sites near young vents and fumaroles. A maximum CO2 flux of 570 g m-2 day-1 was measured at a location adjacent to a fumarole. Using statistical methods appropriate for lognormally distributed populations of data, estimates of the geothermal flux range from 7.5 t day-1 from a 0.14-km2 site near the Stillwater Fault to 0.1 t day-1 from a 0.01 -km2 location of steaming ground on the valley floor. Anomalous CO2 flux is positively correlated with shallow temperature anomalies. The anomalous flux associated with the entire dead zone area declined about 35% over a 6-month period. The decline was most notable at a hot zone located on an alluvial fan and in the SG located on the valley floor. Gas geochemistry indicates that older established fumaroles along the Stillwater Fault and a 2-year-old vent in the lower section of the dead zone discharge a mixture of geothermal gases and air or gases from air-saturated meteoric water (ASMW). Stable isotope data indicate that steam from the smaller fumaroles is produced by ??? 100??C boiling of these mixed fluids and reservoir fluid. Steam from the Senator fumarole (SF) and from shallow wells penetrating the dead zone are probably derived by 140??C to 160??C boiling of reservoir fluid. Carbon-13 isotope data suggest that the reservoir CO2 is produced mainly by thermal decarbonation of

  14. Progress of the LASL dry hot rock geothermal energy project

    NASA Technical Reports Server (NTRS)

    Smith, M. C.

    1974-01-01

    The possibilities and problems of extracting energy from geothermal reservoirs which do not spontaneously yield useful amounts of steam or hot water are discussed. The system for accomplishing this which is being developed first is a pressurized-water circulation loop intended for use in relatively impermeable hot rock. It will consist of two holes connected through the hot rock by a very large hydraulic fracture and connected at the surface through the primary heat exchanger of an energy utilization system. Preliminary experiments in a hole 2576 ft (0.7852 km) deep, extending about 470 ft (143 m) into the Precambrian basement rock underlying the Jemez Plateau of north-central New Mexico, revealed no unexpected difficulties in drilling or hydraulically fracturing such rock at a temperature of approximately 100 C, and demonstrated a permeability low enough so that it appeared probable that pressurized water could be contained by the basement rock. Similar experiments are in progress in a second hole, now 6701 ft (2.043 km) deep, about 1.5 miles (2.4 km) south of the first one.

  15. Groundwater contamination mechanism in a geothermal field: A case study of Balcova, Turkey

    NASA Astrophysics Data System (ADS)

    Aksoy, Niyazi; Şimşek, Celalettin; Gunduz, Orhan

    2009-01-01

    The Balcova Geothermal Field (BGF) located in Izmir, Turkey is situated on an east-west directed graben plain within which the hot waters surface from a fault zone that cuts the Mesozoic aged Bornova Flysch. Due to the low permeability and porosity of the Bornova Flysch, the geothermal water cycles along the immediate vicinity of the Agamemnon fault and mixes with cold waters at different depths of this fractured zone. Within the scope of this study, the mixing patterns and the groundwater contamination mechanisms are analyzed by, hydrogeological and hydrogeochemical methods. Based on the results of this research, it has been found out that the hot geothermal water and the cold regional groundwater resources of the surficial aquifer mix within the fractured zone in Bornova Flysch and within the Quaternary alluvium aquifer due to natural and anthropogenic activities including (i) the natural upward movement of geothermal fluid along the fault line, (ii) the accelerated upward seepage of geothermal fluid from faulty constructed boreholes drilled in the area, (iii) the faulty reinjection applications; and, (iv) the uncontrolled discharge of waste geothermal fluid to the natural drainage network. As a result of these activities, the cold groundwater reserves of the alluvial aquifer are contaminated thermally and chemically in such a way that various toxic chemicals including arsenic, antimony and boron are introduced to the heavily used surficial aquifer waters hindering their use for human consumption and agricultural irrigation. Furthermore, the excessive pumping from the surficial aquifer as well as the reduced surface water inflow into BGF due to the dam constructed on Ilica Creek intensify the detrimental effects of this contamination. Based on the results of this study, it can be concluded that the groundwater pollution in BGF will expand and reach to the levels of no return unless a series of preventive measures is taken immediately.

  16. Groundwater contamination mechanism in a geothermal field: a case study of Balcova, Turkey.

    PubMed

    Aksoy, Niyazi; Simşek, Celalettin; Gunduz, Orhan

    2009-01-01

    The Balcova Geothermal Field (BGF) located in Izmir, Turkey is situated on an east-west directed graben plain within which the hot waters surface from a fault zone that cuts the Mesozoic aged Bornova Flysch. Due to the low permeability and porosity of the Bornova Flysch, the geothermal water cycles along the immediate vicinity of the Agamemnon fault and mixes with cold waters at different depths of this fractured zone. Within the scope of this study, the mixing patterns and the groundwater contamination mechanisms are analyzed by, hydrogeological and hydrogeochemical methods. Based on the results of this research, it has been found out that the hot geothermal water and the cold regional groundwater resources of the surficial aquifer mix within the fractured zone in Bornova Flysch and within the Quaternary alluvium aquifer due to natural and anthropogenic activities including (i) the natural upward movement of geothermal fluid along the fault line, (ii) the accelerated upward seepage of geothermal fluid from faulty constructed boreholes drilled in the area, (iii) the faulty reinjection applications; and, (iv) the uncontrolled discharge of waste geothermal fluid to the natural drainage network. As a result of these activities, the cold groundwater reserves of the alluvial aquifer are contaminated thermally and chemically in such a way that various toxic chemicals including arsenic, antimony and boron are introduced to the heavily used surficial aquifer waters hindering their use for human consumption and agricultural irrigation. Furthermore, the excessive pumping from the surficial aquifer as well as the reduced surface water inflow into BGF due to the dam constructed on Ilica Creek intensify the detrimental effects of this contamination. Based on the results of this study, it can be concluded that the groundwater pollution in BGF will expand and reach to the levels of no return unless a series of preventive measures is taken immediately.

  17. Inverse modeling and forecasting for the exploitation of the Pauzhetsky geothermal field, Kamchatka, Russia

    SciTech Connect

    Finsterle, Stefan; Kiryukhin, A.V.; Asaulova, N.P.; Finsterle, S.

    2008-04-01

    A three-dimensional numerical model of the Pauzhetsky geothermal field has been developed based on a conceptual hydrogeological model of the system. It extends over a 13.6-km2 area and includes three layers: (1) a base layer with inflow; (2) a geothermal reservoir; and (3) an upper layer with discharge and recharge/infiltration areas. Using the computer program iTOUGH2 (Finsterle, 2004), the model is calibrated to a total of 13,675 calibration points, combining natural-state and 1960-2006 exploitation data. The principal model parameters identified and estimated by inverse modeling include the fracture permeability and fracture porosity of the geothermal reservoir, the initial natural upflow rate, the base-layer porosity, and the permeabilities of the infiltration zones. Heat and mass balances derived from the calibrated model helped identify the sources of the geothermal reserves in the field. With the addition of five makeup wells, simulation forecasts for the 2007-2032 period predict a sustainable average steam production of 29 kg/s, which is sufficient to maintain the generation of 6.8 MWe at the Pauzhetsky power plant.

  18. 36Cl/Cl ratios in geothermal systems: preliminary measurements from the Coso Field

    SciTech Connect

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

    1997-07-01

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

  19. Advanced Horizontal Well Recirculation Systems for Geothermal Energy Recovery in Sedimentary and Crystalline Formations

    SciTech Connect

    Bruno, Mike S.; Detwiler, Russell L.; Lao, Kang; Serajian, Vahid; Elkhoury, Jean; Diessl, Julia; White, Nicky

    2012-12-13

    There is increased recognition that geothermal energy resources are more widespread than previously thought, with potential for providing a significant amount of sustainable clean energy worldwide. Recent advances in drilling, completion, and production technology from the oil and gas industry can now be applied to unlock vast new geothermal resources, with some estimates for potential electricity generation from geothermal energy now on the order of 2 million megawatts. The primary objectives of this DOE research effort are to develop and document optimum design configurations and operating practices to produce geothermal power from hot permeable sedimentary and crystalline formations using advanced horizontal well recirculation systems. During Phase I of this research project Terralog Technologies USA and The University of California, Irvine (UCI), have completed preliminary investigations and documentation of advanced design concepts for paired horizontal well recirculation systems, optimally configured for geothermal energy recovery in permeable sedimentary and crystalline formations of varying structure and material properties. We have also identified significant geologic resources appropriate for application of such technology. The main challenge for such recirculation systems is to optimize both the design configuration and the operating practices for cost-effective geothermal energy recovery. These will be strongly influenced by sedimentary formation properties, including thickness and dip, temperature, thermal conductivity, heat capacity, permeability, and porosity; and by working fluid properties.

  20. Colorado geothermal commercialization program: community development of geothermal energy in Pagosa Springs, Colorado

    SciTech Connect

    Coe, B.A.

    1980-01-01

    A district heating system for the Pagosa Springs central business district is in the planning stage. A detailed analysis of the project is presented. It comprises area and site specific studies and describes in detail the recent, current, anticipated, and postulated geothermal development activities. (MHR)

  1. Did stresses from the Cerro Prieto Geothermal Field influence the El Mayor-Cucapah rupture sequence?

    NASA Astrophysics Data System (ADS)

    Trugman, Daniel T.; Borsa, Adrian A.; Sandwell, David T.

    2014-12-01

    The Mw 7.2 El Mayor-Cucapah (EMC) earthquake ruptured a complex fault system in northern Baja California that was previously considered inactive. The Cerro Prieto Geothermal Field (CPGF), site of the world's second largest geothermal power plant, is located approximately 15 km to the northeast of the EMC hypocenter. We investigate whether anthropogenic fluid extraction at the CPGF caused a significant perturbation to the stress field in the EMC rupture zone. We use Advanced Land Observing Satellite interferometric synthetic aperture radar data to develop a laterally heterogeneous model of fluid extraction at the CPGF and estimate that this extraction generates positive Coulomb stressing rates of order 15 kPa/yr near the EMC hypocenter, a value which exceeds the local tectonic stressing rate. Although we cannot definitively conclude that production at the CPGF triggered the EMC earthquake, its influence on the local stress field is substantial and should not be neglected in local seismic hazard assessments.

  2. Efficient Use of Geothermal Energy in Spas - Call for Improvements

    NASA Astrophysics Data System (ADS)

    Straka, W.; Ponweiser, K.; Gollob, K.; Götzl, G.; Schneider, J. F.

    2009-04-01

    In Central Europe, the Pannonian Basin and adjacent areas are holding some of the most attractive geothermal energy resources available from subsurface hot water reservoirs. In fact, utilization of geothermal energy has a long-standing tradition in the region, mainly for thermal and medicinal bathing. Nevertheless, putting to use the extractable heat in a technical and economical optimum manner, and integrating the various energy flows (heating, cooling, vitiated air, etc.) in the application system as well as returning the cooled effluent (excluding used bath water) back to the reservoir, has not found general acceptance to date. This is regrettable not least because thermal spas can be regarded as virtually ideal objects for an integrated management of energy flows on a low temperature level. Hardly any other facilities are in nearly constant, year-round need of heat at a low temperature, as is actually delivered by most thermal aquifers. Also, waste heat and solar energy can be added without much inconvenience, and if hotels and/or therapeutic facilities are to be supplied, there will be cooling demand as well. Many spas in the region are about to update their technology. Complementing this development by an initiative for an integrated and therefore economical use of all the heat sinks and sources that may be present was the main objective of the "network project" PANTHERM (www.pantherm.eu) designed at the University of Applied Life Sciences and Natural Resources, Vienna, in cooperation with four Austrian and ten Hungarian, Slovak and Slovenian partners, and funded by the Austrian Research Promotion Agency, Vienna. In the course of a technical feasibility study it was dealt with the problem, and - by example of the spa of Sárvár in Hungary - demonstrated also, in which way the given mass and energy flows need to be interconnected in order to achieve an optimum energy yield, always with an eye on cost-effectiveness and sustainability. The other Eastern

  3. Reservoir simulation studies: Wairakei Geothermal Field, New Zealand. Final report

    SciTech Connect

    Pritchett, J.W.; Rice, L.F.; Garg, S.K.

    1980-01-01

    Numerical reservoir simulation techniques were used to perform a history-match of the Wairakei geothermal system in New Zealand. First, a one-dimensional (vertical) model was chosen; realistic stratigraphy was incorporated and the known production history was imposed. The effects of surface and deep recharge were included. Good matches were obtained, both for the reservoir pressure decline history and changes in average discharge enthalpy with time. Next, multidimensional effects were incorporated by treating with a two-dimensional vertical section. Again, good history matches were obtained, although computed late-time discharge enthalpies were slightly high. It is believed that this disparity arises from inherently three-dimensional effects. Predictive calculations using the two-dimensional model suggest that continued future production will cause little additional reservoir pressure drop, but that thermal degradation will occur. Finally, ground subsidence data at Wairakei was examined. It was concluded that traditional elastic pore-collapse models based on classical soil-mechanics concepts are inadequate to explain the observed surface deformation. It is speculated that the measured subsidence may be due to structural effects such as aseismic slippage of a buried reservoir boundary fault.

  4. Geothermal energy employment and requirements 1977-1990

    SciTech Connect

    Not Available

    1981-12-01

    An assessment of the manpower needs of the geothermal industry is presented. The specific objectives were to: derive a base line estimate of the manpower involved in geothermal activities, determine if there is any current or impending likelihood of skill shortages, forecast future employment in the geothermal industry, conduct a technology assessment to ascertain the possibilities of some sudden breakthrough, and suggest alternatives commensurate with the findings. The methodology for fulfilling the objectives is described. Detailed results of these pursuits (objectives) are presented. Alternatives that are suggested, based upon the findings of the study, are summarized.

  5. Advanced geothermal technologies

    NASA Astrophysics Data System (ADS)

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

    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 U.S. 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 was 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.

  6. Results of investigations at the Zunil geothermal field, Guatemala: Well logging and brine geochemistry

    SciTech Connect

    Adams, A.; Dennis, B.; Van Eeckhout, E.; Goff, F.; Lawton, R.; Trujillo, P.E.; Counce, D.; Archuleta, J. ); Medina, V. . Unidad de Desarollo Geotermico)

    1991-07-01

    The well logging team from Los Alamos and its counterpart from Central America were tasked to investigate the condition of four producing geothermal wells in the Zunil Geothermal Field. The information obtained would be used to help evaluate the Zunil geothermal reservoir in terms of possible additional drilling and future power plant design. The field activities focused on downhole measurements in four production wells (ZCQ-3, ZCQ-4, ZCQ-5, and ZCQ-6). The teams took measurements of the wells in both static (shut-in) and flowing conditions, using the high-temperature well logging tools developed at Los Alamos National Laboratory. Two well logging missions were conducted in the Zunil field. In October 1988 measurements were made in well ZCQ-3, ZCQ-5, and ZCQ-6. In December 1989 the second field operation logged ZCQ-4 and repeated logs in ZCQ-3. Both field operations included not only well logging but the collecting of numerous fluid samples from both thermal and nonthermal waters. 18 refs., 22 figs., 7 tabs.

  7. 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.

  8. Conceptual models for the hydrothermal environment of Seokmo Island geothermal field, Korea

    NASA Astrophysics Data System (ADS)

    Shin, J.; Lee, Y.; Kim, K.; Hyun, Y.; Lee, K.; Lee, T.

    2010-12-01

    Geothermal exploration for the first geothermal power plant in Korea is undergoing in Seokmo Island, where a few artesian wells with relatively high water temperature of ~70°C have been discovered recently. The geothermal gradient in the site is up to ~45°C/km and the geothermal water is as saline as seawater. The discharge rate of geothermal water and the vertical temperature distribution vary significantly even in a small area. Therefore, hydrothermal behavior in this field seems to be related to the fracture system which could act as a conduit, even if any detailed investigation on the structure and the distribution of the fractured system has not been completed yet. Several conceptual models for the groundwater flow and the convective heat transfer in the fractured medium of the Seokmo Island region are suggested as: 1) topography-driven flow, 2) density-driven flow, and 3) artesian flow caused by the pressure difference. All of these possible scenarios reflecting any known hydraulic and geothermal factors were evaluated by numerical models. Topography-driven flow is resulted from the recharge on the mountains and the discharge through the permeable fracture. This model is suitable to describe the artesian wells near the foot of the mountains, but the rain-originated water could not explain the saline chemistry of the geothermal water. Density-driven flow is caused by the heating from the anomalously high basal heat flux. In this model, water flowing through the fractured medium is considerably heated at depth and the lighter hot water comes to rise through the permeable fracture. The estimated temperature of the geothermal water should be higher than the observed one so that it can lead to considerable density difference. Artesian flow caused by the pressure difference is based on the stress variation in the fractured rock medium. This model considers some extended fractures connected from the deep aquifer. It is possible to explain any of the artesian flow

  9. Geothermal resources of California sedimentary basins

    USGS Publications Warehouse

    Williams, C.F.; Grubb, F.V.; Galanis, S.P.

    2004-01-01

    The 2004 Department of Energy (DOE) Strategic Plan for geothermal energy calls for expanding the geothermal resource base of the United States to 40,000 MW of electric power generating potential. This will require advances in technologies for exploiting unconventional geothermal resources, including Enhanced Geothermal Systems (EGS) and geopressured geothermal. An investigation of thermal conditions in California sedimentary basins through new temperature and heat flow measurements reveals significant geothermal potential in some areas. In many of the basins, the combined cooling effects of recent tectonic and sedimentary processes result in relatively low (<60 mW/m2) heat flow and geothermal gradients. For example, temperatures in the upper 3 km of San Joaquin, Sacramento and Ventura basins are typically less than 125??C and do not reach 200??c by 5 km. By contrast, in the Cuyama, Santa Maria and western Los Angeles basins, heat flow exceeds 80 mW/m2 and temperatures near or above 200??C occur at 4 to 5 km depth, which represents thermal conditions equivalent to or hotter than those encountered at the Soultz EGS geothermal site in Europe. Although the extractable geothermal energy contained in these basins is not large relative to the major California producing geothermal fields at The Geysers or Salton Sea, the collocation in the Los Angeles basin of a substantial petroleum extraction infrastructure and a major metropolitan area may make it attractive for eventual geothermal development as EGS technology matures.

  10. Information systems and technology transfer programs on geothermal energy and other renewable sources of energy

    SciTech Connect

    Lippmann, M.J.; Antunez, E.

    1996-01-01

    In order to remain competitive, it is necessary to stay informed and use the most advanced technologies available. Recent developments in communication, like the Internet and the World Wide Web, enormously facilitate worldwide data and technology transfer. A compilation of the most important sources of data on renewable energies, especially geothermal, as well as lists of relevant technology transfer programs are presented. Information on how to gain access to, and learn more about them, is also given.

  11. Information systems and technology transfer programs on geothermal energy and other renewable sources of energy

    SciTech Connect

    Lippmann, Marcelo J.; Antunez, Emilio u.

    1996-01-24

    In order to remain competitive it is necessary to stay informed and use the most advanced technologies available. Recent developments in communication, like the Internet and the World Wide Web, enormously facilitate worldwide data and technology transfer. A compilation of the most important sources of data on renewable energies, especially geothermal, as well as lists of relevant technology transfer programs are presented. Information on how to gain access to, and learn more about them is also given.

  12. Assessing geothermal energy potential in upstate New York. Final report, Tasks 1, 3, and 4

    SciTech Connect

    Manger, K.C.

    1996-07-25

    New York State`s geothermal energy potential was evaluated based on a new resource assessment performed by the State University of New York at Buffalo (SUNY-Buffalo) and currently commercial technologies, many of which have become available since New York`s potential was last evaluated. General background on geothermal energy and technologies was provided. A life-cycle cost analysis was performed to evaluate the economics of using geothermal energy to generate electricity in upstate New York. A conventional rankine cycle, binary power system was selected for the economic evaluation, based on SUNY-Buffalo`s resource assessment. Binary power systems are the most technologically suitable for upstate New York`s resources and have the added advantage of being environmentally attractive. Many of the potential environmental impacts associated with geothermal energy are not an issue in binary systems because the geothermal fluids are contained in a closed-loop and used solely to heat a working fluid that is then used to generate the electricity Three power plant sizes were selected based on geologic data supplied by SUNY-Buffalo. The hypothetical power plants were designed as 5 MW modular units and sized at 5 MW, 10 MW and 15 MW. The life-cycle cost analysis suggested that geothermal electricity in upstate New York, using currently commercial technology, will probably cost between 14 and 18 cents per kilowatt-hour.

  13. Potential for substitution of geothermal energy at domestic defense installations and White Sands Missile Range

    SciTech Connect

    Bakewell, C.A.; Renner, J.L.

    1982-01-01

    Geothermal resources that might provide substitute energy at any of 76 defense installations are identified and evaluated. The geologic characteristics and related economics of potential geothermal resources located at or near the 76 installations were estimated. The geologic assessment identified 18 installations with possible geothermal resources and 4 Atlantic Coastal Plain resource configurations that represented the alternatives available to East Coast bases. These 18 locations and 4 resource configurations, together with 2 possible resources at the White Sands Missile Range and a potential resource at Kings Bay, Georgia, were examined to determine the relative economics of substituting potential geothermal energy for part or all of the existing oil, gas, and electrical energy usage. Four of the military installations - Mountain Home, Norton, Hawthorne, and Sierra - appear to be co-located with possible geothermal resources which, if present, might provide substitute energy at or below current market prices for oil. Six additional locations - Ellsworth, Luke, Williams, Bliss, Fallon, and Twentynine Palms - could become economically attractive under certain conditions. No geothermal resource was found to be economically competitive with natural gas at current controlled prices. Generation of electric power at the locations studied is estimated to be uneconomic at present.

  14. Geothermal Energy Research and Development Program; Project Summaries

    SciTech Connect

    1994-03-01

    This is an internal DOE Geothermal Program document. This document contains summaries of projects related to exploration technology, reservoir technology, drilling technology, conversion technology, materials, biochemical processes, and direct heat applications. [DJE-2005

  15. Dynamic triggering of microearthquakes in the Long Valley Caldera and Coso Geothermal Field

    NASA Astrophysics Data System (ADS)

    Aiken, C.; Peng, Z.; Wu, C.

    2010-12-01

    Recent studies have shown that microearthquakes can be dynamically triggered by the passing of surface waves from regional and teleseismic events. However, the underlying physical mechanisms and the necessary conditions that favor dynamic triggering are still in debate. Here we conduct a systematic search of dynamically triggered microearthquakes around the Long Valley Caldera (LVC) and Coso Geothermal Field (CGF) in California. In each region, we select distant mainshocks in 1999-2010 with M>=7.5 over 1000 km away, or M>=5.5 between 100-2500 km. Next, we apply 2-8 or 2-16 Hz band-pass-filtered data to the three-component seismograms recorded at each region, and identify triggered events as high-frequency seismic energy during large-amplitude surface waves of regional and teleseismic events. We calculate the beta statistic values based on events listed in the local earthquake catalogs and hand-picked events from the envelope functions, and verify that the triggering is statistically significant. Based on this simple procedure, we have identified many distant events that have triggered activity in both regions, including the recent 08/03/2009 and 04/04/2010 Baja California earthquakes at regional distances, and the 02/27/2010 Chile earthquake at teleseismic distances. Our next steps are to examine the dynamic triggering thresholds in each region, and to understand the triggering potential in terms of frequency, amplitude, incident angle, and type of surface waves.

  16. Proceedings of the Conference on Research for the Development of Geothermal Energy Resources

    NASA Technical Reports Server (NTRS)

    1974-01-01

    The proceedings of a conference on the development of geothermal energy resources are presented. The purpose of the conference was to acquaint potential user groups with the Federal and National Science Foundation geothermal programs and the method by which the users and other interested members can participate in the program. Among the subjects discussed are: (1) resources exploration and assessment, (2) environmental, legal, and institutional research, (3) resource utilization projects, and (4) advanced research and technology.

  17. Advanced Condenser Boosts Geothermal Power Plant Output (Fact Sheet), The Spectrum of Clean Energy Innovation

    SciTech Connect

    Not Available

    2010-12-01

    When power production at The Geysers geothermal power complex began to falter, the National Renewable Energy Laboratory (NREL) stepped in, developing advanced condensing technology that dramatically boosted production efficiency - and making a major contribution to the effective use of geothermal power. NREL developed advanced direct-contact condenser (ADCC) technology to condense spent steam more effectively, improving power production efficiency in Unit 11 by 5%.

  18. Preliminary reservoir engineering studies of the Miravalles geothermal field, Costa Rica

    SciTech Connect

    Haukwa, C.; Bodvarsson, G.S.; Lippmann, M.J.; Mainieri, A.

    1992-01-01

    The Earth Sciences Division of Lawrence Berkeley Laboratory in cooperation with the Instituto Costarricense de Electricidad is conducting a reservoir engineering study of the Miravalles geothermal field, Costa Rica. Using data from eight exploration wells, a two-dimensional areal, natural-state model of Miravalles has been developed. The model was calibrated by fitting the observed temperature and pressure distributions and requires a geothermal upflow zone in the northern part of the field, associated with the Miravalles volcano and an outflow towards the south. The total hot (about 260 C) water recharge is 130 kg/s, corresponding to a thermal input of about 150 MWt. On the basis of the natural-state model a two-dimensional exploitation model was developed. The field has a production area of about 10 km{sup 2}, with temperatures exceeding 220 C. The model indicated that power generation of 55 MWe can be maintained for 30 years, with or without injection of the separated geothermal brine. Generation of 110 MWe could be problematic. Until more information becomes available on the areal extent of the field and the properties of the reservoir rocks, especially their relative permeability characteristics, it is difficult to ascertain if 110 MWe can be sustained during a 30-year period.

  19. Preliminary reservoir engineering studies of the Miravalles geothermal field, Costa Rica

    SciTech Connect

    Haukwa, C.; Bodvarsson, G.S. Lippmann, M.J. ); Mainieri, A. )

    1992-01-01

    The Earth Sciences Division of Lawrence Berkeley Laboratory in cooperation with the Instituto Costarricense de Electricidad is conducting a reservoir engineering study of the Miravalles geothermal field, Costa Rica. Using data from eight exploration wells a two-dimensional areal, natural-state model of Miravalles has been developed. The model was calibrated by fitting the observed temperature and pressure distributions and requires a geothermal upflow zone in the northern part of the field, associated with the Miravalles volcano and an outflow towards the south. The total hot (about 260[degrees]C) water recharge is 130 kg/s, corresponding to a thermal input of about 150 MWt. On the basis of the natural-state model a two-dimensional exploitation model was develope. The field has a production area of about 10 km[sup 2], with temperatures exceeding 220[degrees]C. The model indicated that power generation of 55 MWe can be maintained for 30 years, with or without injection of the separated geothermal brine. Generation of 110 MWe could be problematic. Until more information becomes available on the areal extent of the field and the properties of the reservoir rocks, especially their relative permeability characteristics, it is difficult to ascertain if 110 MWe can be sustained during a 30-year period.

  20. Preliminary reservoir engineering studies of the Miravalles geothermal field, Costa Rica

    SciTech Connect

    Haukwa, C.; Bodvarsson, G.S. Lippmann, M.J.; Mainieri, A.

    1992-01-01

    The Earth Sciences Division of Lawrence Berkeley Laboratory in cooperation with the Instituto Costarricense de Electricidad is conducting a reservoir engineering study of the Miravalles geothermal field, Costa Rica. Using data from eight exploration wells a two-dimensional areal, natural-state model of Miravalles has been developed. The model was calibrated by fitting the observed temperature and pressure distributions and requires a geothermal upflow zone in the northern part of the field, associated with the Miravalles volcano and an outflow towards the south. The total hot (about 260{degrees}C) water recharge is 130 kg/s, corresponding to a thermal input of about 150 MWt. On the basis of the natural-state model a two-dimensional exploitation model was develope. The field has a production area of about 10 km{sup 2}, with temperatures exceeding 220{degrees}C. The model indicated that power generation of 55 MWe can be maintained for 30 years, with or without injection of the separated geothermal brine. Generation of 110 MWe could be problematic. Until more information becomes available on the areal extent of the field and the properties of the reservoir rocks, especially their relative permeability characteristics, it is difficult to ascertain if 110 MWe can be sustained during a 30-year period.

  1. Connecting Anthropogenic Seismicity Rates To Operational Parameters At The Salton Sea Geothermal Field, Southern California (Invited)

    NASA Astrophysics Data System (ADS)

    Brodsky, E. E.; Lajoie, L. J.

    2013-12-01

    Geothermal power is generated at several major volcanic fields in California. As efforts to monitor seismicity increase, methods to understand the anthropogenic component need to improve. Ideally, induced earthquake rate should be forecast based on publicly-reported volumes of fluid injection or other operational parameters. At the flash facilities in the Salton Sea Geothermal Field, the total volume of fluid extracted or injected tracks the long-term evolution of seismicity. However, for recent years net fluid volume (extracted-injected) is better correlated with seismicity. After correcting for the variable aftershock rate using an Epidemic-Type Aftershock Sequence model (ETAS), we fit the background earthquake rate with a linear combination of injection and net production rate that allows us to track the secular evolution of the field. The number of earthquakes per fluid volume injected decreases gradually over time. In the Salton Sea Geothermal Field, the new analysis of induced seismicity provides a template for future evaluation of hazard directly based on measureable, controllable operational quantities. The interactions of these anthropogenic events with the larger-scale tectonic and volcanic systems remains to be investigated. Results of the linear model of seismicity based on a combination of net production and injection. (a) Example of observed seismicity rate and model prediction using the reported fluid data and the best-fit linear model. (b) Number of earthquakes triggered per net volume of fluid extracted or total fluid injection.

  2. Fracture mapping in geothermal fields with long-offset induction logging

    SciTech Connect

    Wilt, M.; Takasugi, Shinji; Uchida, Toshihiro

    1997-12-31

    The mapping of producing fractures in a geothermal field is an important technical objective in field development. Locating, orienting, and assessing producing fractures can guide drilling programs and optimize the placement of production and injection wells. A long-offset multicomponent borehole induction resistivity tool capable of surviving the high temperatures encountered in geothermal wells has recently been developed in a NEDO project, {open_quotes}Deep-Seated Geothermal Reservoirs,{close_quotes} and tested in a high temperature environment. Several characteristics of this device make it ideal for detecting producing fractures. Whereas commercial induction logging devices have source-receiver separations of 1 m, this device has multiple sensors with separations up to 8 m, allowing for deeper penetration and the ability to straddle fracture-induced washout zones in boreholes. The three-component measurements also make it possible to map the strike and inclination of nearby fractures and other three-dimensional structures. This, in turn, allows for accurate projection of these structures into the space between wells. In this paper, we describe the design of the tool and show results of a performance test carried out in an oil-field steam flood. Data from vertical sensors are compared to conventional logging results and indicate the recent formation of a low-resistivity zone associated with high temperatures due to steam flood breakthrough. Horizontal field data indicate that the high-temperature zone is irregular in the vicinity of the borehole and more pronounced closest to the steam injector.

  3. Geology and geothermal origin of Grant Canyon and Bacon Flat Oil Fields, Railroad Valley, Nevada

    SciTech Connect

    Hulen, J.B. ); Goff, F. ); Ross, J.R. ); Bortz, L.C. ); Bereskin, S.R. )

    1994-04-01

    Eastern Nevada's Grant Canyon and Bacon Flat oil fields show strong evidence of formation in a still-active, moderate-temperature geothermal system. Modern manifestations of this system include unusually elevated oil-reservoir temperature at shallow depth, 116-122[degrees]C at 1.1-1.6 km, and dilute Na-HCO[sub 3]Cl thermal waters directly associated with hot oil. Hydrogen and oxygen isotopic compositions indicate that these thermal waters are meteoric in origin, but were probably recharged prior to the Holocene (before 10 ka). The waters apparently ascended to oil-reservoir elevations after deep heating in response to the normal regional thermal gradient; there is no evidence for a modern magmatic heat source. The beginning of oil-reservoir evolution at both fields is recorded by late-stage, fracture-filling quartz in the vuggy, brecciated, Paleozoic dolostone reservoir rocks. Oil and aqueous solutions were trapped as fluid inclusions in the quartz at temperatures comparable to those now prevailing in the reservoirs. Present day and fluid-inclusion temperatures define essentially coincident isothermal profiles through and beneath the oil-reservoir interval, a phenomenon consistent with near-constant convective heat transfer since inception of the geothermal system. Some basin and range oil fields have arisen as valuable byproducts of actively circulating geothermal systems and blending this concept into current exploration stratigies could hasten discovery of the 100 mbbl fields many geologists believe remain to be found in this region. 100 refs., 13 figs., 5 tabs.

  4. 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.

  5. 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.

  6. Case studies on developing local industry by using hot spring water and geothermal energy

    SciTech Connect

    Sasaki, Akira; Umetsu, Yoshio; Narita, Eiichi

    1997-12-31

    We have investigated the new ways to develop local industries by using hot spring water, geothermal water and geothermal energy from the Matsukawa Geothermal Power Plant in Iwate Prefecture, which is the first geothermal power plant established in Japan. The new dyeing technique, called {open_quotes}Geothermal Dyeing{close_quotes} was invented in which hydrogen sulfide in the water exhibited decoloration effect. By this technique we succeeded to make beautiful color patterns on fabrics. We also invented the new way to make the light wight wood, called {open_quotes}Geo-thermal Wood{close_quotes} by using hot spring water or geothermal water. Since polysaccharides in the wood material were hydrolyzed and taken out during the treatment in the hot spring water, the wood that became lighter is weight and more porous state. On the bases of these results, we have produced {open_quotes}Wooded Soap{close_quotes} on a commercial scale which is the soap, synthesized in the pore of the treated wood in round slice. {open_quotes}Collapsible Wood Cabin{close_quotes} was also produced for enjoyable outdoor life by using the modified properties of Geothermal Wood.

  7. Preliminary plan for the development of geothermal energy in the town of Gabbs, Nevada

    SciTech Connect

    Not Available

    1981-11-09

    The results of the analyses as well as a plan for geothermal development are described. The major findings and specific barriers to development that would have to be addressed are identified. Characteristics of the site significant to the prospect for geothermal development are described. These characteristics include physiography, demography, economy, and the goals and objectives of the citizens as they would relate to geothermal development. The geothermal resource evaluation is described. Based on available information, the reservoir is generally described, defining the depth to the reservoir, production rates of the existing water wells, water quality, and the resource temperature. Uses of the energy that seem appropriate to the situation both now and in the foreseeable future at Gabbs are described. The amounts and types of energy currently consumed, by end-user, are estimated. From this information, a conceptual engineering design and cost estimates are presented. Finally, the results of a life cycle analysis of the economic feasibility are discussed. A time-line chart shows the tasks, the time estimated to be required for each and the interrelatioships among the activities. The essential institutional requirements for geothermal energy development are discussed. These include the financial, environmental, legal and regulatory requirements. The main resource, engineering, and institutional considerations involved in a geothermal district heating system for Gabbs are summarized.

  8. Preliminary plan for the development of geothermal energy in the town of Hawthorne, Nevada

    SciTech Connect

    Not Available

    1981-11-04

    The results of the analyses as well as a plan for the development of the geothermal resource are described. Site characteristics pertinent to the geothermal development are described. These characteristics include physiography, demography, economy, and goals and ojectives of the citizens as they would relate to geothermal development. The geothermal resource is described. The reservoir is characterized on the basis of available information. The probable drilling depth to the reservoir, anticipated water production rates, water quality, and resource temperatures ae indicated. Uses of the energy that seem appropriate to the situation both now and in the near future at Hawthorne are described. The amounts and types of energy currently consumed by end users are estimated. Using this data base, conceptual engineering designs and cost estimates for three alternative district heating systems are presented. In addition, the results of a life cycle cost analysis for these alternatives are discussed. The essential institutional requirements for geothermal energy development, including the financial, environmental, and legal and regulatory aspects are discussed. The various steps that are necessary to accomplish the construction of the geothermal district heating system at Hawthorne are described. A time-line chart shows the tasks, the time estimated to be required for each, and the interrelationships among the activities.

  9. Fracture mapping in geothermal fields with long-offset induction logging

    SciTech Connect

    Wilt, M.; Takasugi, Shinji; Uchida, Toshihiro; Kasameyer, P.; Lee, Ki Ha; Lippmann, M.

    1997-01-01

    The mapping of producing fractures in a geothermal field is an important technical objective in field development. Locating, orientating, and assessing producing fractures can guide drilling programs and optimize the placement of production and injection wells. A long-offset multicomponent borehole induction resistivity tool capable of surviving the high temperatures encountered in geothermal wells has recently been developed and tested in a high temperature environment. Several characteristics of this device make it ideal for detecting producing fractures. Whereas commercial induction logging devices have strong source-receiver separations of 1 m, this device has multiple sensors with separation of 8 m, allowing for deeper penetrations and the ability to straddle fracture-induced washout zones in boreholes. The three-component measurements also make it possible to map the strike and inclination of nearby fractures and other three-dimensional structures. This in turn allows for accurate projection of these structures into the space between wells.

  10. 3-D seismic velocity and attenuation structures in the geothermal field

    SciTech Connect

    Nugraha, Andri Dian; Syahputra, Ahmad; Fatkhan,; Sule, Rachmat

    2013-09-09

    We conducted delay time tomography to determine 3-D seismic velocity structures (Vp, Vs, and Vp/Vs ratio) using micro-seismic events in the geothermal field. The P-and S-wave arrival times of these micro-seismic events have been used as input for the tomographic inversion. Our preliminary seismic velocity results show that the subsurface condition of geothermal field can be fairly delineated the characteristic of reservoir. We then extended our understanding of the subsurface physical properties through determining of attenuation structures (Qp, Qs, and Qs/Qp ratio) using micro-seismic waveform. We combined seismic velocities and attenuation structures to get much better interpretation of the reservoir characteristic. Our preliminary attanuation structures results show reservoir characterization can be more clearly by using the 3-D attenuation model of Qp, Qs, and Qs/Qp ratio combined with 3-D seismic velocity model of Vp, Vs, and Vp/Vs ratio.

  11. Fluid inclusions in minerals from the geothermal fields of Tuscany, Italy

    USGS Publications Warehouse

    Belkin, H.; de Vivo, B.; Gianelli, G.; Lattanzi, P.

    1985-01-01

    A reconnaissance study on fluid inclusions from the geothermal fields of Tuscany indicates that the hydrothermal minerals were formed by fluids which were, at least in part, boiling. Four types of aqueous inclusions were recognized: (A) two-phase (liquid + vapor) liquid rich, (B) two-phase (vapor + liquid) vapor rich, (C) polyphase hypersaline liquid rich and (D) three phase-H2O liquid + CO2 liquid + CO2-rich vapor. Freezing and heating microthermometric determinations are reported for 230 inclusions from samples from six wells. It is suggested that boiling of an originally homogeneous, moderately saline, CO2-bearing liquid phase produced a residual hypersaline brine and a CO2-rich vapor phase. There are indications of a temperature decrease in the geothermal field of Larderello, especially in its peripheral zones. ?? 1985.

  12. Field trip guide to the Valles Caldera and its geothermal systems

    SciTech Connect

    Goff, F.E.; Bolivar, S.L.

    1983-12-01

    This field trip guide has been compiled from extensive field trips led at Los Alamos National Laboratory during the past six years. The original version of this guide was designed to augment a workshop on the Valles Caldera for the Continental Scientific Drilling Program (CSDP). This workshop was held at Los Alamos, New Mexico, 5-7 October 1982. More stops were added to this guide to display the volcanic and geothermal features at the Valles Caldera. The trip covers about 90 miles (one way) and takes two days to complete; however, those who wish to compress the trip into one day are advised to use the designated stops listed in the Introduction. Valles Caldera and vicinity comprise both one of the most exciting geothermal areas in the United States and one of the best preserved Quaternary caldera complexes in the world.

  13. Field tests of 2- and 40-tube condensers at the East Mesa Geothermal Test Site

    SciTech Connect

    Murphy, R.W.; Domingo, N.

    1982-05-01

    Two water-cooled isobutane condensers, one with 2 tubes and one with 40 tubes, were subjected to field tests at the East Mesa Geothermal Test Site to assess relative heat transfer performance in both surface evaporator and direct-contact evaporator modes. The five groups of tests established that field performance was below earlier laboratory-determined levels and that direct-contact evaporator mode performance was poorer than that for the surface evaporator mode. In all test situations, fluted condenser tubes performed better than smooth condenser tubes. Cooling water quality had no significant effect on performance, but brine preflash in the direct-contact mode did promote some relative performance improvement. Important implications of these results for binary geothermal power plants are that (1) working-fluid-side impurities can significantly degrade heat transfer performance of the power plant condensers and (2) provisions for minimizing such impurities may be required.

  14. Slope stability analysis of landslide in Wayang Windu Geothermal Field, Pangalengan, West Java Province, Indonesia

    NASA Astrophysics Data System (ADS)

    Yuhendar, A. H.; Wusqa, U.; Kartiko, R. D.; Raya, N. R.; Misbahudin

    2016-05-01

    Large-scale landslide occurred in Margamukti village, Pangalengan, Bandung Regency, West Java Province, Indonesia. The landslide damaged geothermal gas pipeline along 300 m in Wayang Windu Geothermal Field. Based on field observation, landslide occured in rotational sliding movement. Laboratory analysis were conducted to obtain the characteristics of the soil. Based on the condition of the landslide in this area, the Factor of Safety can be simulated by the soil mechanics approach. Factor of safety analysis based on soil cohesion and internal friction angle was conducted using manual sensitivity analysis for back analysis. The analysis resulted soil cohesion in critical condition (FS<1) is 6.01 kPa. This value is smaller than cohesion of undisturbed slope soil sample. Water from rainfall is the most important instability factors in research area. Because it decreases cohesion in soils and increases weight and pore water pressure in granular media.

  15. Body and Surface-wave ambient noise seismic interferometry in the Salton Sea Geothermal Field, California

    NASA Astrophysics Data System (ADS)

    Sabey, L.; Hole, J. A.; Han, L.; Stock, J. M.; Fuis, G. S.

    2013-12-01

    Seismic reflection and refraction data were acquired as a part of the Salton Seismic Imaging Project in March 2011. Alongside traditional explosive source recording, a dense array of 486 seismometers across the Salton Sea Geothermal Field and Brawley Seismic Zone recorded 135 hours of natural noise sources. The geothermal field is located within the Imperial Valley in Southern California and is bordered by the southern end of the Salton Sea. There is abundant microseismicity recorded in the area, including over 100-recorded earthquakes, wave action, geothermal pumping operations, a railroad, and two highways. Volcanism associated with rifting processes provides a prolific heat source to the system marking the Salton Sea Geothermal Field as one of the largest and hottest geothermal fields in California. Seismic interferometry is a technique that uses continuous recordings of natural noise to create a 'virtual source' by cross-correlation of receiver pairs followed by stacking. This method has been highly successful for surface waves and a few previous studies have shown evidence of body waves and reflections. As anticipated the abundant tectonic and induced noise sources within our study area produced visible surface and body waves. Inclusion of the earthquakes with normalized amplitudes improved overall data quality. The virtual shots from our data our compare well to our twelve explosive shots at near offsets. The highest quality virtual source gathers are produced near anthropogenic noise sources. In particular, one large geothermal plant acted as a sufficiently strong point source producing a gather similar to what we would see from an explosive source. Surface waves recorded on 4.5-Hz geophones were retrievable from 1-6Hz after cross-correlation and stacking. Up to 30km of body waves were also observed in the 25-30Hz range. Future studies will include surface wave dispersion analysis and attempt body wave reflection imaging. The 100-meter spacing of our

  16. Spectral reflectance analysis of hydrothermal alteration in drill chips from two geothermal fields, Nevada

    NASA Astrophysics Data System (ADS)

    Lamb, A. K.; Calvin, W. M.

    2010-12-01

    We surveyed drill chips with a lab spectrometer in the visible-near infrared (VNIR) and short-wave infrared (SWIR) regions, 0.35-2.5 μm, to evaluate hydrothermal alteration mineralogy of samples from two known geothermal fields in western Nevada. Rock is fractured into small pieces or “chips” during drilling and stored in trays by depth interval. The drill chips are used to determine subsurface properties such as lithology, structure, and alteration. Accurately determining alteration mineralogy in the geothermal reservoir is important for indicating thermal fluids (usually associated with fluid pathways such as faults) and the highest temperature of alteration. Hydrothermal minerals, including carbonates, iron oxides, hydroxides, sheet silicates, and sulfates, are especially diagnostic in the VNIR-SWIR region.. The strength of reflectance spectroscopy is that it is rapid and accurate for differentiating temperature-sensitive minerals that are not visually unique. We examined drill chips from two western Nevada geothermal fields: Hawthorne (two wells) and Steamboat Springs (three wells) using an ASD lab spectrometer with very high resolution. The Steamboat Hills geothermal field has produced electricity since 1988 and is well studied, and is believed to be a combination of extensional tectonics and magmatic origin. Bedrocks are Cretaceous granodiorite intruding into older metasediments. Hot springs and other surface expressions occur over an area of about 2.6 km2. In contrast, the Hawthorne geothermal reservoir is a ‘blind’ system with no surface expressions such as hot springs or geysers. The geothermal field is situated in a range front fault zone in an extensional area, and is contained in Mesozoic mixed granite and meta-volcanics. We collected spectra at each interval in the chip trays. Interval length varied between 10’ and 30’. - Endmember analysis and mineral identification were performed -using standard analysis approaches used to map mineralogy

  17. Community Geothermal Technology Program: Fruit drying with geothermal energy. Final report

    SciTech Connect

    Not Available

    1988-03-14

    Largest problem was lack of proper recording and controlling instrumentation. Agricultural products tested were green papaya powder, banana slices, and pineapple slices. Results show that a temperature of 120 F is a good drying temperature. Papaya should be mature green and not overly ripe; banana ripeness is also important; and pineapple slice thickness should be very uniform for even drying. Geothermal drying is feasible. Figs, tabs.

  18. 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.

  19. Interpretation of interference effects in three production wells in the Kawerau geothermal field, New Zealand

    SciTech Connect

    Stevens, Lynell; Koorey, Kevin J.

    1996-01-24

    Downhole temperature and pressure, mass flow, and enthalpy measurements on three production wells at Kawerau geothermal field are interpretted to illustrate interference effects between these wells. Feed zone locations within the wells, together with geology and chemistry are discussed. Downhole measurements are made in one well while production flow changes are made on another well to monitor pressure transient effects. The interference effects have implications for planning future production drilling.

  20. Decline curve analysis of production data from The Geysers geothermal field

    SciTech Connect

    Ripperda, M.; Bodvarsson, G.S.

    1987-01-01

    Production data for over two hundred wells at The Geysers geothermal field were compiled and analyzed. Decline curves for groups of wells with 5, 10, and 40 acre spacing are presented and compared to curves published previously by Budd (1972) and Dykstra (1981). Decline curves for several individual wells and leases are discussed to illustrate the effects of well spacing and location, as well as the heterogeneous nature of the reservoir.

  1. Decline Curve Analysis of Production Data from the Geysers Geothermal Field

    SciTech Connect

    Ripperda, M.; Bodvarsson, G.S.

    1987-01-20

    Production data for over two hundred wells at The Geysers geothermal field were compiled and analysed. Decline curves for groups of wells with 5, 10, and 40 acre spacing are presented and compared to curves published previously by Budd (1972) and Dykstra (1981). Decline curves for several individual wells and leases are discussed to illustrate the effects of well spacing and location, as well as the heterogeneous nature of the reservoir. 6 figs., 1 tab., 10 refs.

  2. The projection of world geothermal energy consumption from time series and regression model

    NASA Astrophysics Data System (ADS)

    Simanullang, Elwin Y.; Supriatna, Agus; Supriatna, Asep K.

    2015-12-01

    World population growth has many impacts on human live activities and other related aspects. One among the aspects is the increase of the use of energy to support human daily activities, covering industrial aspect, transportation, domestic activities, etc. It is plausible that the higher the population size in a country the higher the needs for energy to support all aspects of human activities in the country. Considering the depletion of petroleum and other fossil-based energy, recently there is a tendency to use geothermal as other source of energy. In this paper we will discuss the prediction of the world consumption of geothermal energy by two different methods, i.e. via the time series of the geothermal usage and via the time series of the geothermal usage combined with the prediction of the world total population. For the first case, we use the simple exponential smoothing method while for the second case we use the simple regression method. The result shows that taking into account the prediction of the world population size giving a better prediction to forecast a short term of the geothermal energy consumption.

  3. Development of a geothermal resource in a fractured volcanic formation: Case study of the Sumikawa Geothermal Field, Japan. Final report, May 1, 1995--November 30, 1997

    SciTech Connect

    Garg, S.K.; Combs, J.; Pritchett, J.W.

    1997-07-01

    The principal purpose of this case study of the Sumikawa Geothermal Field is to document and to evaluate the use of drilling logs, surface and downhole geophysical measurements, chemical analyses and pressure transient data for the assessment of a high temperature volcanic geothermal field. This comprehensive report describes the work accomplished during FY 1993-1996. A brief review of the geological and geophysical surveys at the Sumikawa Geothermal Field is presented (Section 2). Chemical data, consisting of analyses of steam and water from Sumikawa wells, are described and interpreted to indicate compositions and temperatures of reservoir fluids (Section 3). The drilling information and downhole pressure, temperature and spinner surveys are used to determine feedzone locations, pressures and temperatures (Section 4). Available injection and production data from both slim holes and large-diameter wells are analyzed to evaluate injectivity/productivity indices and to investigate the variation of discharge rate with borehole diameter (Section 5). New interpretations of pressure transient data from several wells are discussed (Section 6). The available data have been synthesized to formulate a conceptual model for the Sumikawa Geothermal Field (Section 7).

  4. Microearthquake Study of the Salton Sea Geothermal Field, California: Evidence of Stress Triggering - Masters Thesis

    SciTech Connect

    Holland, Austin Adams

    2002-02-01

    A digital network of 24 seismograph stations was operated from September 15, 1987 to September 30, 1988, by Lawrence Livermore National Laboratory and Unocal as part of the Salton Sea Scientific Drilling Project to study seismicity related to tectonics and geothermal activity near the drilling site. More than 2001 microearthquakes were relocated in this study in order to image any pervasive structures that may exist within the Salton Sea geothermal field. First, detailed velocity models were obtained through standard 1-D inversion techniques. These velocity models were then used to relocate events using both single event methods and Double-Differencing, a joint hypocenter location method. An anisotropic velocity model was built from anisotropy estimates obtained from well logs within the study area. During the study period, the Superstition wills sequence occurred with two moderate earthquakes of MS 6.2 and MS 6.6. These moderate earthquakes caused a rotation of the stress field as observed from the inversion of first motion data from microearthquakes at the Salton Sea geothermal field. Coulomb failure analysis also indicates that microearthquakes occurring after the Superstition Hills sequence are located within a region of stress increase suggesting stress triggering caused by the moderate earthquakes.

  5. 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.

  6. 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.

  7. Faults dominant structure? -Seismic images of the subsurface structure for the Ilan geothermal field in Taiwan.

    NASA Astrophysics Data System (ADS)

    Chang, Yu-Chun; Shih, Ruey-Chyuan; Wang, Chien-Ying; Kuo, Hsuan-Yu; Chen, Wen-Shan

    2016-04-01

    A prototype deep geothermal power plant is to be constructed at the Ilan plain in northeastern Taiwan. The site will be chosen from one of the two potential areas, one in the west and the other in the eastern side of the plain. The triangle-shaped Ilan plane is bounded by two mountain ranges at the northwest and the south, with argillite and slate outcrops exposed, respectively. The Ilan plane is believed situating in a structure extending area at the southwestern end of the Okinawa Trough. Many studies about subsurface structure of the plain have been conducted for years. The results showed that the thickest sediments, around 900 m, is located at the eastern coast of the plain, at north of the largest river in the plain, the Lanyang river, and then became shallower to the edges of the plain. Since the plane is covered by thick sediments, formations and structures beneath the sediments are barely known. However, the observed high geothermal gradient and the abundant hot spring in the Ilan area indicate that this area is having a high potential of geothermal energy. In order to build up a conceptual model for tracing the possible paths of geothermal water and search for a suitable site for the geothermal well, we used the seismic reflection method to delineate the subsurface structure. The seismic profiles showed a clear unconformity separating the sediments and the metamorphic bedrock, and some events dipping to the east in the bedrock. Seismic images above the unconformity are clear; however, seismic signals in the metamorphic bedrock are sort of ambiguous. There were two models interpreted by using around 10 seismic images that collected by us in the past 3 years by using two mini-vibrators (EnviroVibe) and a 360-channel seismic data acquisition system. In the first model, seismic signals in the bedrock were interpreted as layer boundaries, and a fractured metamorphic layer down the depth of 1200m was thought as the source of geothermal water reservoir. In the

  8. Open questions on the origin of life at anoxic geothermal fields.

    PubMed

    Mulkidjanian, Armen Y; Bychkov, Andrew Yu; Dibrova, Daria V; Galperin, Michael Y; Koonin, Eugene V

    2012-10-01

    We have recently reconstructed the 'hatcheries' of the first cells by combining geochemical analysis with phylogenomic scrutiny of the inorganic ion requirements of universal components of modern cells (Mulkidjanian et al. Proc Natl Acad Sci U S A 109:E821-830, 2012). These ubiquitous, and by inference primordial, proteins and functional systems show affinity to and functional requirement for K⁺, Zn²⁺, Mn²⁺, and phosphate. Thus, protocells must have evolved in habitats with a high K⁺/Na⁺ ratio and relatively high concentrations of Zn, Mn and phosphorous compounds. Geochemical reconstruction shows that the ionic composition conducive to the origin of cells could not have existed in marine settings but is compatible with emissions of vapor-dominated zones of inland geothermal systems. Under an anoxic, CO₂-dominated atmosphere, the ionic composition of pools of cool, condensed vapor at anoxic geothermal fields would resemble the internal milieu of modern cells. Such pools would be lined with porous silicate minerals mixed with metal sulfides and enriched in K⁺ ions and phosphorous compounds. Here we address some questions that have appeared in print after the publication of our anoxic geothermal field scenario. We argue that anoxic geothermal fields, which were identified as likely cradles of life by using a top-down approach and phylogenomics analysis, could provide geochemical conditions similar to those which were suggested as most conducive for the emergence of life by the chemists who pursuit the complementary bottom-up strategy.

  9. Abrupt physical and chemical changes during 1992-1999, Anderson Springs, SE Geyser Geothermal Field, California

    USGS Publications Warehouse

    Janik, Cathy J.; Goff, Fraser; Walter, Stephen R.; Sorey, Michael L.; Counce, Dale; Colvard, Elizabeth M.

    2000-01-01

    The Anderson Springs area is located about 90 miles (145 kilometers) north of San Francisco, California, in the southwestern part of Lake County. The area was first developed in the late 1800s as a health resort, which was active until the 1930s. Patrons drank a variety of cool to hot mineral waters from improved springs, swam in various baths and pools, and hiked in the rugged hills flanking Anderson Creek and its tributaries. In the bluffs to the south of the resort were four small mercury mines of the eastern Mayacmas quicksilver district. About 1,260 flasks of mercury were produced from these mines between 1909 and 1943. By the early 1970s, the higher ridges south and west of Anderson Springs became part of the southeast sector of the greater Geysers geothermal field. Today, several electric power plants are built on these ridges, producing energy from a vapor-dominated 240 °C reservoir. Only the main hot spring at Anderson Springs has maintained a recognizable identity since the 1930s. The hot spring is actually a cluster of seeps and springs that issue from a small fault in a ravine southwest of Anderson Creek. Published and unpublished records show that the maximum temperature (Tm) of this cluster fell gradually from 63°C in 1889 to 48°C in 1992. However, Tm of the cluster climbed to 77°C in 1995 and neared boiling (98°C) in 1998. A new cluster of boiling vents and small fumaroles (Tm = 99.3°C) formed in 1998 about 30 m north of the old spring cluster. Several evergreen trees on steep slopes immediately above these vents apparently were killed by the new activity. Thermal waters at Anderson Hot Springs are mostly composed of near-surface ground waters with some added gases and condensed steam from The Geysers geothermal system. Compared to gas samples from Southeast Geysers wells, the hot spring gases are higher in CO2 and lower in H2S and NH3. As the springs increased in temperature, however, the gas composition became more like the mean composition

  10. Recoverable Resource Estimate of Identified Onshore Geopressured Geothermal Energy in Texas and Louisiana (Presentation)

    SciTech Connect

    Esposito, A.; Augustine, C.

    2012-04-01

    Geopressured geothermal reservoirs are characterized by high temperatures and high pressures with correspondingly large quantities of dissolved methane. Due to these characteristics, the reservoirs provide two sources of energy: chemical energy from the recovered methane, and thermal energy from the recovered fluid at temperatures high enough to operate a binary power plant for electricity production. Formations with the greatest potential for recoverable energy are located in the gulf coastal region of Texas and Louisiana where significantly overpressured and hot formations are abundant. This study estimates the total recoverable onshore geopressured geothermal resource for identified sites in Texas and Louisiana. In this study a geopressured geothermal resource is defined as a brine reservoir with fluid temperature greater than 212 degrees F and a pressure gradient greater than 0.7 psi/ft.

  11. Direct use of geothermal energy, Elko, Nevada district heating. Final report

    SciTech Connect

    Lattin, M.W.; Hoppe, R.D.

    1983-06-01

    In early 1978 the US Department of Energy, under its Project Opportunity Notice program, granted financial assistance for a project to demonstrate the direct use application of geothermal energy in Elko, Nevada. The project is to provide geothermal energy to three different types of users: a commercial office building, a commercial laundry and a hotel/casino complex, all located in downtown Elko. The project included assessment of the geothermal resource potential, resource exploration drilling, production well drilling, installation of an energy distribution system, spent fluid disposal facility, and connection of the end users buildings. The project was completed in November 1982 and the three end users were brought online in December 1982. Elko Heat Company has been providing continuous service since this time.

  12. Leyte `A` geothermal project optimization: Review of improved resource performance and power generation strategies for the greater Tongonan field. Export trade information

    SciTech Connect

    1992-11-01

    The Consultant Team (the team) visited the Philippines the weeks of October 24 and November 9, 1992, in order to review and discuss the resource and power generation optimization work underway for the Greater Tongonan Geothermal field on the island of Leyte being developed by the Philippine National Oil Company - Energy Development Corporation (PNOC-EDC). The team`s work is managed by PNOC-EDC and funded by the United States Trade and Development Program (USTDP).

  13. Fact sheets relating to use of geothermal energy in the United States

    SciTech Connect

    1980-12-01

    A compilation of data relating to geothermal energy in each of the 50 states is presented. The data are summarized on one page for each state. All summary data sheets use a common format. Following the summary data sheet there are additional data on the geology of each state pertaining to possible hydrothermal/geothermal resources. Also there is a list of some of the reports available pertaining to the state and state energy contacts. The intent of these documents is to present in a concise form reference data for planning by the Department of Energy.

  14. Volcanic rock petrochemistry as an exploration technique for geothermal energy

    SciTech Connect

    Fultz, L.A.; Bell, E.J.; Trexler, D.T.

    1983-12-01

    Large high-level silicic magma chambers offer a high potential for economically viable geothermal systems. While purely basic volcanic systems rarely form thermal anomalies, they may provide the necessary long-term heat input to silicic systems, by underplating, to sustain a high-temperature geothermal system. Petrographic and microprobe, geochemical, geochronologic, and isotopic data on young volcanic rocks in west-central Nevada indicate compositions that may result from magmatic differentiation, crystal fractionation, variation in magmatic source regions and in particular, magma mixing. Analysis of the petrochemistry and the recognition of magma mixing textures of extrusive rocks may indicate interacting mafic magma with buried shallow silicic magma systems. These systems may provide a shallow heat source for development of geothermal resources.

  15. A joint geophysical analysis of the Coso geothermal field, south-eastern California

    NASA Astrophysics Data System (ADS)

    Wamalwa, Antony M.; Mickus, Kevin L.; Serpa, Laura F.; Doser, Diane I.

    2013-01-01

    Three-dimensional density models derived from gravity data and two-dimensional resistivity models derived from magnetotelluric data collected in the vicinity of the Coso geothermal field are analyzed in order to determine the source region of the geothermal field. The derived models show zones of both low resistivity and low density at and below 6 km depth in the Devils Kitchen and the Coso Hot Springs areas. These zones agree with seismic reflection and tomography results which found a high amplitude reflector at 5 km and low velocities zones below 5 km. We interpret the density and resistivity zones to indicate the presence of cooling magmatic material that provides the heat for the shallower geothermal system in these regions. A zone marked by high resistivity and low density was found to lie directly above the interpreted partially melted region extending to within 1 km depth below the surface in the reservoir region where it is capped by a low resistivity clay zone. In addition, the density models indicate that the high density bodies occurring under volcanic outcrops may be mafic intrusions.

  16. Sustainable development of geothermal fields in the Pannonian Basin - A case study

    SciTech Connect

    Panu, Dumitru; Mitrofan, Horia; Serbu, Viorel

    1996-01-24

    As suggested by the discusssion of Barker, 1988, on the influence of flow dimension on the late-time behaviour of the generalized line source solution, it was inferred that observed long term reservoir pressure decline was an outcome of the 1D (linear) flow geometry, indicated by well tests. The detrimental effects of the reservoir pressure decline can be partly mitigated by taking advantage of the two-phase flow which occurs when methane, originally dissolved in the geothermal brine, is released within the well bore. Sustainable artesiar withdrawal scenarios for existing geothermal fields are devised, based on an accurate prediction of bottomhole pressure decline trends and an adequate selection of the diameter and length of the production tubing. Overall analysis and forecast are performed by an integrated reservoir & well bore simulator.

  17. Fluid flow in the Rotorua geothermal field derived from isotopic and chemical data

    SciTech Connect

    Stewart, M.K.; Lyon, G.L.; Robinson, B.W. ); Glover, R.B. )

    1992-04-01

    A wide variety of isotopic and chemical measurements on geothermal fluids from shallow wells at Rotorua have given the following interpretations: The Rotorua field comprises one geothermal system; a primary upflow of (outgassed) alkali chloride water extends from northeast Whakarewarewa to Ngapuna and under Lake Rotorua (east side of the system). At the southern end a secondary upflow discharges dilute alkali chloride water; a second major upflow at Kuirau-Ohinmutu discharges chloride-bicarbonate waters formed by dilution of the primary water and reaction with rock; boiling primary water flows from the eastern upflow zone under confining sediments into aquifers in Rotorua Rhyolite containing chloride-bicarbonate waters in the central region; tritium-bearing groundwater penetrates from overlying aquifers in the sediment into the saddle area between the rhyolite domes or along the crest of the southern rhyolite dome and flows northeast into the northern dome.

  18. Plant adaptation to extreme environments: the example of Cistus salviifolius of an active geothermal alteration field.

    PubMed

    Bartoli, Giacomo; Bottega, Stefania; Forino, Laura M C; Ciccarelli, Daniela; Spanò, Carmelina

    2014-02-01

    Cistus salviifolius is able to colonise one of the most extreme active geothermal alteration fields in terms of both soil acidity and hot temperatures. The analyses of morpho-functional and physiological characters, investigated in leaves of plants growing around fumaroles (G leaves) and in leaves developed by the same plants after transfer into growth chamber under controlled conditions (C leaves) evidenced the main adaptive traits developed by this pioneer plant in a stressful environment. These traits involved leaf shape and thickness, mesophyll compactness, stomatal and trichome densities, chloroplast size. Changes of functional and physiological traits concerned dry matter content, peroxide and lipid peroxidation, leaf area, relative water and pigment contents. A higher reducing power and antioxidant enzymatic activity were typical of G leaves. Though the high levels of stress parameters, G leaves showed stress-induced specific morphogenic and physiological responses putatively involved in their surviving in active geothermal habitats.

  19. Regional hydrology of the Dixie Valley geothermal field, Nevada: preliminary interpretations of chemical and isotopic data

    SciTech Connect

    Counce, D; Dunlap, C; Goff, F; Huebner, M; Janik, C; Johnson, S; Nimz, G

    1999-08-16

    Chemical and isotopic analyses of Dixie Valley regional waters indicate several distinct groups ranging in recharge age from Pleistocene (<20 ka) to recent (<50a). Valley groundwater is older than water from perennial springs and artesian wells in adjacent ranges, with Clan Alpine range (east) much younger (most <50a) than Stillwater range (west; most >1000a). Geothermal field fluids ({approximately}12-14 ka) appear derived from water similar in composition to non-thermal groundwater observed today in valley artesian wells (also -14 ka). Geothermal fluid interaction with mafic rocks (Humboldt Lopolith) appears to be common, and significant reaction with granodiorite may also occur. Despite widespread occurrence of carbonate rocks, large scale chemical interaction appears minor. Age asymmetry of the ranges, more extensive interaction with deep-seated waters in the west, and distribution of springs and artesian wells suggest the existence of a regional upward hydrologic gradient with an axis in proximity to the Stillwater range.

  20. Gas Geothermometry Based on CO Content--Application in Italian Geothermal Fields

    SciTech Connect

    D'Amore, F.; Fancelli, R.; Saracco, L.; Truesdell, A.H.

    1987-01-20

    This paper discusses gas chemical equilibria in geothermal reservoirs involving the species CO{sub 2}, CH{sub 4}, CO, H{sub 2}S, H{sub 2}, and H{sub 2}O. A set of equations is developed correlating ratios of gas to CO{sub 2} with temperature, steam fraction, and CO{sub 2} partial pressure in the reservoir. A method for solving the set of nonlinear equations is proposed. These equations do not involve discharge gas/total H{sub 2}O ratios and may therefore be used for fumaroles and hot-spring fluids. Applications to fumarole and well-discharge fluid compositions in Italian geothermal fields show good correlations between temperatures calculated with this method and the temperatures measured in the reservoir (between 140° to 330°C). 5 tabs., 1 fig., 19 refs.

  1. Regional hydrology of the Dixie Valley geothermal field, Nevada: preliminary interpretations of chemical and isotopic data

    USGS Publications Warehouse

    Nimz, Gregory; Janik, Cathy; Goff, Fraser; Dunlap, Charles; Huebner, Mark; Counce, Dale; Johnson, Stuart D.

    1999-01-01

    Chemical and isotopic analyses of Dixie Valley regional waters indicated several distinct groups ranging in recharge age from Pleistocene (1000a). Geothermal field fluids (~12-14 ka) appear derived from water similar in composition to non thermal groundwater observed today in valley artesian well (also ~14 ka). Geothermal fluid interaction with mafic rocks (Humboldt Lopolith) appears to be common, and significant reaction with granodiorite may also occur. Despite widespread occurrence of carbonate rocks, large scale chemical interaction appears minor. Age asymmetry of the range, more extensive interaction with deep seated waters in the west, and distribution of springs and artesian wells suggest the existence of a regional upward hydrologic gradient with an axis in proximity to the Stillwater range.

  2. Hydrothermal alteration of sediments associated with surface emissions from the Cerro Prieto geothermal field

    SciTech Connect

    Valette-Silver, J.N.; Esquer P., I.; Elders, W.A.; Collier, P.C.; Hoagland, J.R.

    1981-01-01

    A study of the mineralogical changes associated with these hydrothermal vents was initiated with the aim of developing possible exploration tools for geothermal resources. The Cerro Prieto reservoir has already been explored by extensive deep drilling so that relationships between surface manifestations and deeper hydrothermal processes could be established directly. Approximately 120 samples of surface sediments were collected both inside and outside of the vents. The mineralogy of the altered sediments studied appears to be controlled by the type of emission. A comparison between the changes in mineralogy due to low temperature hydrothermal activity in the reservoir, seen in samples from boreholes, and mineralogical changes in the surface emission samples shows similar general trends below 180 C: increase of quartz, feldspar and illite, with subsequent disappearance of kaolinite, montmorillonite, calcite and dolomite. These mineral assemblages seem to be characteristic products of the discharge from high intensity geothermal fields.

  3. Mercury in freshwater fish and clams from the Cerro Prieto geothermal field of Baja California, Mexico

    SciTech Connect

    Gutierrez-Galindo, E.A.; Munoz, G.F.; Flores, A.A.

    1988-08-01

    Several reports have expressed concern about the potential toxicity hazards and environmental contamination of mercury emissions from geothermal fields in Hawaii, New Zealand, Iceland, California and Mexico. Inorganic mercury discharged from the sources may accumulate in the sediments of rivers or lakes and, after microbiological methylation may become concentrated in the edible tissue of fish. This study involves assessment of geothermal mercury pollution arising from Cerro Prieto. For this purpose the fish Tilapia mossambica and the clam Corbicula fluminea were collected from the freshwater courses of the Mexicali Valley. Reports indicated that in 1982, 13 t of T. mossambica were destinated for human consumption. A further aim was to provide base line data and information relevant to the level of mercury contamination for the Mexicali Valley.

  4. Plant adaptation to extreme environments: the example of Cistus salviifolius of an active geothermal alteration field.

    PubMed

    Bartoli, Giacomo; Bottega, Stefania; Forino, Laura M C; Ciccarelli, Daniela; Spanò, Carmelina

    2014-02-01

    Cistus salviifolius is able to colonise one of the most extreme active geothermal alteration fields in terms of both soil acidity and hot temperatures. The analyses of morpho-functional and physiological characters, investigated in leaves of plants growing around fumaroles (G leaves) and in leaves developed by the same plants after transfer into growth chamber under controlled conditions (C leaves) evidenced the main adaptive traits developed by this pioneer plant in a stressful environment. These traits involved leaf shape and thickness, mesophyll compactness, stomatal and trichome densities, chloroplast size. Changes of functional and physiological traits concerned dry matter content, peroxide and lipid peroxidation, leaf area, relative water and pigment contents. A higher reducing power and antioxidant enzymatic activity were typical of G leaves. Though the high levels of stress parameters, G leaves showed stress-induced specific morphogenic and physiological responses putatively involved in their surviving in active geothermal habitats. PMID:24581804

  5. Supercritical heat exchanger field test (SHEFT), I. Field performance data on shell-and-tube heat exchangers in geothermal service

    SciTech Connect

    Silvester, L.F.; Beaulaurier, L.O.; Mirk, K.F.; Fulton, R.L.

    1981-06-01

    Field performance data on shell-and-tube heat exchangers in geothermal service are presented. The test data were taken for geothermal brine on the tube side and hydrocarbon on the shell side in counterflow for six primary heat exchangers, and for hydrocarbon on the shell side and cooling water on the tube side for the condenser. Test data were for heating isobutane, 1 90/10 isobutane/isopentane mixture, and a 80/20 isobutane/isopentane mixture at supercritical conditions in the vicinity of their critical pressure and temperature, and for condensing the same fluids. The test data were used in a preliminary data analysis to determine the reported heat exchanger performance parameters.

  6. Field tests to determine scaling tendency of some moderate-temperature geothermal brines

    SciTech Connect

    Robertus, R.J.; Sullivan, R.G.; Shannon, D.W.

    1986-09-01

    Several field tests were completed to determine the scaling tendency of moderate-temperature geothermal brines. Data were taken on the Heber as well as the East Mesa Known-Geothermal-Resources-Areas (KGRA's). The test results most directly benefit the Heber Geothermal Binary Demonstration Plant, but some have been generalized to be useful for other moderate-temperature (302 to 460/sup 0/F (150 to 239/sup 0/C)) geothermal reservoirs also. Field experiments determined conditions under which calcite, silica, and metal sulfides are likely to form. The calcite tests determined pressures which must be maintained to prevent gas-breakout and ensuing calcite deposition. Required pressures varied from one reservoir to the next and were strong functions of non-condensable gas content. The brine cooling tests tried to quantify the amount of silica which would drop out of the Heber brine by incrementally cooling it below a design set point of 150/sup 0/F (66/sup 0/C). The conclusion was that no detectable increase in silica occurred in times relevant to plant operations when the brine was cooled to 120/sup 0/F (49/sup 0/C). Although the cooling tests showed no detectable increase in silica formation, other materials did form in small amounts. The list includes magnetite (Fe/sub 3/O/sub 4/), calcite (CaCO/sub 3/), and mixtures of lead, zinc, and arsenic sulfides. Even for the lowest outlet temperature (120/sup 0/F) the particulate loading increased only about 50% over inlet conditions. Thus, for the Heber brines, the majority of material entering an injection well comes in the form of sand from the production wells. This same conclusion was supported by earlier work on the East Mesa KGRA.

  7. Reservoir Characterization around Geothermal Field, West Java, Indonesia Derived from 4-D Seismic Tomography

    NASA Astrophysics Data System (ADS)

    Verdhora Ry, Rexha; Nugraha, A. D.

    2016-01-01

    Observation of micro-seismic events induced by intensive geothermal exploitation in a particular geothermal field, located in West Java region, Indonesia was used to detect the fracture and permeability zone. Using local monitoring seismometer network, tomographic inversions were conducted for the three-dimensional Vp, Vs, and Vp/Vs structure of the reservoir for January - December 2007, January - December 2008, and January - December 2009. First, hypocenters location was relocated using joint hypocenter determination (JHD) method in purpose to estimate best location. Then, seismic tomographic inversions were conducted using delay time tomography for dataset of every year respectively. The travel times passing through the three-dimensional velocity model were calculated using ray tracing pseudo-bending method. Norm and gradient damping were added to constrain blocks without ray and to produce smooth solution model. The inversion algorithm was developed in Matlab environment. Our tomographic inversion results from 3-years of observations indicate the presence of low Vp, low Vs, and low Vp/Vs ratio at depths of about 1 - 3 km below sea level. These features were interpreted may be related to steam-saturated rock in the reservoir area of this geothermal field. The locations of the reservoir area were supported by the data of well- trajectory, where the zones of high Vp/Vs were observed around the injection wells and the zones of low Vp/Vs were observed around the production wells. The extensive low Vp/Vs anomaly that occupies the reservoir is getting stronger during the 3-years study period. This is probably attributed to depletion of pore liquid water in the reservoir and replacement with steam. Continuous monitoring of Vp, Vs, and Vp/Vs is an effective tool for geothermal reservoir characterization and depletion monitoring and can potentially provide information in parts of the reservoir which have not been drilled.

  8. Monitoring and mapping of hydrogen sulphide emissions across an active geothermal field: Rotorua, New Zealand

    NASA Astrophysics Data System (ADS)

    Horwell, C. J.; Patterson, J. E.; Gamble, J. A.; Allen, A. G.

    2005-01-01

    Hydrogen sulphide (H 2S) is one of a number of gaseous species associated with geothermal activity in the Taupo Volcanic Zone (TVZ), New Zealand. The city of Rotorua is located within Rotorua Caldera in the TVZ and is one of the few urban areas in the world where a large population (>60,000 people) is frequently exposed to geothermal emissions. In order to evaluate the health hazard from long-term exposure to H 2S being emitted from the Rotorua geothermal field, a passive sampler has been developed to measure concentrations of H 2S at many locations across the city simultaneously. In contrast to other passive or pump-based samplers, the sampler is inexpensive, easily mass-manufactured, and involves the reaction of H 2S with silver halide contained in treated photographic paper. H 2S-exposed paper shows a distinct colour change from white to dark brown as H 2S concentrations increase and is sensitive to concentrations between ≪30 and around 1000 ppb. Rotorua city can be divided into three regions—an area of low H 2S concentration in the west, a 'corridor' of high concentrations running north-south through the city centre where H 2S is being emitted, and an area of medium concentration to the east which is influenced by the prevailing wind direction, creating a plume from the central corridor. The data give new insight into the subsurface routes of degassing in the Rotorua geothermal field, by showing the surface expression of the main upflow zone and the direction of the conjectured faulting below.

  9. Origin of rainwater acidity near the Los Azufres geothermal field, Mexico

    USGS Publications Warehouse

    Verma, M.P.; Quijano, J.L.; Johnson, Chad; Gerardo, J.Y.; Arellano, V.

    2000-01-01

    The chemical and isotopic compositions of rainwater were monitored at Los Azufres geothermal field (88 MWe) and its surroundings during May - September 1995, which is the rainy season. Samples were collected from eight sites: three within the field, three in its surroundings and two sufficiently far from the field such that they have no geothermal input. The concentrations of Cl-, SO42- and NO3- were measured in about 350 samples and found to be generally <5 ppm. Chloride concentrations remained constant with time, but sulfate and nitrate concentrations decreased, which suggests a nearby industrial source for the sulfate and nitrate. A mixing model for Cl-, SO42- and ??34S also suggests an industrial source for the rainwater sulfur. The determination of pH was found to be necessary, but is not sufficient to characterize rainwater acidity. The Gran titration method was used to determine alkalinity with respect to equivalence point of H2CO3(*). Values of alkalinity were found to range from 10-4 to 10-6 eq/L, and were negative only for some samples from Vivero and Guadalajara. Thus, SO42- and NO3- are in general not in acidic form (i.e. balanced by Na+, Ca2+, etc. rather than H+). Sulfate ??34S values were about -1.5??? in Los Azufres and its surroundings, and in Morelia, but differed from the value of -0.2??? for Guadalajara. The ??34S values for H2S from the Los Azufres geothermal wells are in the range -3.4 to 0.0???. The ??34S ranges for the natural and anthropogenic sources for environmental sulfur overlap, making it difficult to differentiate between the contribution of different sources. However, a similarity of values of ??34S at Los Azufres and Morelia (85 km distant) suggest a regional source of sulfate that is not associated with geothermal emissions from Los Azufres. (C) 2000 Published by Elsevier Science Ltd on behalf of CNR.The chemical compositions of rainwater were analyzed at Los Azufres geothermal field in Spain from May-September 1995. The

  10. Recent exploration and development of geothermal energy resources in the Escalante desert region, Southwestern Utah

    USGS Publications Warehouse

    Blackett, Robert E.; Ross, Howard P.

    1994-01-01

    Development of geothermal resources in southwest Utah's Sevier thermal area continued in the early 1990s with expansion of existing power-generation facilities. Completion of the Bud L. Bonnett geothermal power plant at the Cove Fort-Sulphurdale geothermal area brought total power generation capacity of the facility to 13.5 MWe (gross). At Cove Fort-Sulphurdate, recent declines in steam pressures within the shallow, vapor-dominated part of the resource prompted field developers to complete additional geothermal supply wells into the deeper, liquid-dominated portion of the resource. At Roosevelt Hot Springs near Milford, Intermountain Geothermal Company completed an additional supply well for Utah Power and Light Company's single-flash, Blundell plant. with the increased geothermal fluid supply from the new well, the Blundell plant now produces about 26 MWe (gross). The authors conducted several geothermal resource studies in undeveloped thermal areas in southwest Utah. Previous studies at Newcastle revealed a well-defined, self-potential minimum coincident with the intersection of major faults and the center of the heatflow anomaly. A detailed self-potential survey at Wood's Ranch, an area in northwest Iron County where thermal water was encountered in shallow wells, revealed a large (5,900 ?? 2,950 feet [1,800 ?? 900 m]) northeast-oriented self-potential anomaly which possibly results from the flow of shallow thermal fluid. Chemical geothermometry applied to Wood's Ranch water samples suggest reservoir temperatures between 230 and 248??F (110 and 120??C). At the Thermo Hot Springs geothermal area near Minersville, detailed self-potential surveys have also revealed an interesting 100 mV negative anomaly possibly related to the upward flow of hydrothermal fluid.

  11. 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.

  12. Summary of modeling studies of the East Olkaria geothermal field, Kenya

    SciTech Connect

    Bodvarsson, G.S.; Pruess, K.; Stefansson, V.; Bjornsson, S.; Ojiambo, S.B.

    1985-03-01

    A detailed three-dimensional well-by-well model of the East Olkaria geothermal field in Kenya has been developed. The model matches reasonably well the flow rate and enthalpy data from all wells, as well as the overall pressure decline in the reservoir. The model is used to predict the generating capacity of the field, well decline, enthalpy behavior, the number of make-up wells needed and the effects of injection on well performance and overall reservoir depletion. 26 refs., 10 figs.

  13. Flow rate decline and pressure transient in the Larderello geothermal field

    SciTech Connect

    Neri, Guiseppe

    1988-01-01

    The production history of most of the Larderello wells, both the older ones and the recent ones, that we have produced at constant pressure, is characterised by a rapid initial decline. In this study such a decline is interpreted as the consequence of an original flow regime of the “depletion” type being followed by a “diffusion” type regime. Such an interpretation, which does prove consistent with the phenomenology of the geothermal field, was suggested by the results of the analyses of the well-closure tests carried out in the North zone of Larderello and in the Travale field.

  14. Potential of installed thermal power for direct uses of geothermal energy in Japan

    SciTech Connect

    Sekioka, M. )

    1992-01-01

    In this paper it is attempted to estimate potential installed thermal power of direct uses of geothermal energy in Japan by computing extractable heat from only existing thermal springs distributed all over the country, under the presumption that no geothermal well is newly drilled. Since the Japanese enjoy the pleasures of natural baths, direct uses of geothermal energy in Japan are required to coexist with bathing. Then, potential installed thermal power is estimated at 2,797.46 MW under some conditions for coexistence and coprosperity with bathing. However, some disqualifying factors and the average load factor may reduce this value by 530 MW, which will be yet about five times large than the present thermal energy used of 104.69 Mw. THe oil saved will be up to 0.35% of national consumption.

  15. Global Deployment of Geothermal Energy Using a New Characterization in GCAM 1.0

    SciTech Connect

    Hannam, Phil; Kyle, G. Page; Smith, Steven J.

    2009-09-01

    This report documents modeling of geothermal energy in GCAM 1.0 (formerly MiniCAM) from FY2008 to FY2009, from the inputs to the U.S. Climate Change Technology Program report (Clarke et al., 2008a) to the present representation, which will be used in future work. To demonstrate the newest representation, we describe the procedure and outcome of six model runs that illustrate the potential role of geothermal energy in the U.S. and global regions through different futures climate policy, development and deployment of engineered, or enhanced, geothermal systems (EGS), and availability of other low-cost, low-carbon electricity generation technologies such as nuclear energy and carbon capture and storage (CCS).

  16. Laboratory measurements on reservoir rocks from The Geysers geothermal field

    SciTech Connect

    Boitnott, G.N.

    1995-01-26

    A suite of laboratory measurements have been conducted on Geysers metagraywacke and metashale recovered from a drilled depth of 2599 to 2602 meters in NEGU-17. The tests have been designed to constrain the mechanical and water-storage properties of the matrix material. Various measurements have been made at a variety of pressures and at varying degrees of saturation. Both compressional and shear velocities exhibit relatively little change with effective confining pressure. In all of the samples, water saturation causes an increase in the compressional velocity. In some samples, saturation results in a moderate decrease in shear velocity greater in magnitude than would be expected based on the slight increase in bulk density. It is found that the effect of saturation on the velocities can be quantitatively modeled through a modification of Biot-Gassmann theory to include weakening of the shear modulus with saturation. The decrease is attributed to chemo-mechanical weakening caused by the presence of water. The degree of frame weakening of the shear modulus is variable between samples, and appears correlated with petrographic features of the cores. Two related models are presented through which we can study the importance of saturation effects on field-scale velocity variations. The model results indicate that the saturation effects within the matrix are significant and may contribute to previously observed field anomalies. The results help to define ways in which we may be able to separate the effects of variations in rock properties, caused by phenomena such as degree of fracturing, from similar effects caused by variations in matrix saturation. The need for both compressional and shear velocity data in order to interpret field anomalies is illustrated through comparisons of model results with the field observations.

  17. Geothermal energy: Technology and general studies. Citations from the NTIS data base

    NASA Astrophysics Data System (ADS)

    Hundemann, A. S.

    1980-09-01

    This bibliography contains 311 citations of Government-sponsored research on geothermal energy conversion, power plants, heat extraction, and space heating. Studies on fluid flow, heat transfer, rock fracturing, environmental impacts, pressure, and reservoir engineering are included. Reports on economics, legislation, technology assessment, comparative evaluation with other energy sources, Government policies, and planning are also cited.

  18. Biomass production and energy source of thermophiles in a Japanese alkaline geothermal pool.

    PubMed

    Kimura, Hiroyuki; Mori, Kousuke; Nashimoto, Hiroaki; Hattori, Shohei; Yamada, Keita; Koba, Keisuke; Yoshida, Naohiro; Kato, Kenji

    2010-02-01

    Microbial biomass production has been measured to investigate the contribution of planktonic bacteria to fluxations in dissolved organic matter in marine and freshwater environments, but little is known about biomass production of thermophiles inhabiting geothermal and hydrothermal regions. The biomass production of thermophiles inhabiting an 85 degrees C geothermal pool was measured by in situ cultivation using diffusion chambers. The thermophiles' growth rates ranged from 0.43 to 0.82 day(-1), similar to those of planktonic bacteria in marine and freshwater habitats. Biomass production was estimated based on cellular carbon content measured directly from the thermophiles inhabiting the geothermal pool, which ranged from 5.0 to 6.1 microg C l(-1) h(-1). This production was 2-75 times higher than that of planktonic bacteria in other habitats, because the cellular carbon content of the thermophiles was much higher. Quantitative PCR and phylogenetic analysis targeting 16S rRNA genes revealed that thermophilic H2-oxidizing bacteria closely related to Calderobacterium and Geothermobacterium were dominant in the geothermal pool. Chemical analysis showed the presence of H2 in gases bubbling from the bottom of the geothermal pool. These results strongly suggested that H2 plays an important role as a primary energy source of thermophiles in the geothermal pool.

  19. Seismicity and deformation in the Coso Geothermal field from 2000 to 2012

    NASA Astrophysics Data System (ADS)

    Kaven, J. Ole; Hickman, Stephen H.; Davatzes, Nicholas C.

    2015-04-01

    Induced micro-seismicity in geothermal reservoirs, in particular in enhanced geothermal systems (EGS), is an intended byproduct of injection and production, as it often indicates the generation of permeability pathways on either pre-existing or newly generated faults and fractures. The hazard of inducing an earthquake large enough to cause damage to surface structures, however, is not easily avoided and has led to termination of geothermal projects. To explore the physical processes leading to damaging earthquakes, we investigate the evolution of seismicity and the factors controlling the migration, moment release rate, and structure within the seismicity in the Coso Geothermal Field (CGF). The CGF has been in production since the 1980s and includes both naturally occurring geothermal resources and portions of the reservoir that are EGS projects. We report on seismicity in the CGF that has been relocated with high precision double-difference relocation and simultaneous velocity inversion to understand the reservoir compartmentalization, in particular, where boundaries to flow exist both vertically and horizontally. We also calculate moment magnitudes (Mw) from the initial displacement pulse of the seismograms to relate moment directly to the deformation. We find that two distinct compartments form the CGF, which are divided by an aseismic gap that also shows a relatively low Vp/Vs ratio. Further, we find that events with Mw> 3.5 tend to map onto larger fault structures that are imaged by the relocated seismicity. We relate the temporal and spatial migration of moment release rate to the injection and production records in the reservoir by employing a thermo-poro-elastic finite element model in which the compartment boundaries are defined by the seismicity. We find that pore pressure effects alone are not responsible for the migration of seismicity and that poro-elastic and thermo-elastic strain changes can account for more of the observed moment release rate than

  20. Relevance of deep-subsurface microbiology for underground gas storage and geothermal energy production.

    PubMed

    Gniese, Claudia; Bombach, Petra; Rakoczy, Jana; Hoth, Nils; Schlömann, Michael; Richnow, Hans-Hermann; Krüger, Martin

    2014-01-01

    This chapter gives the reader an introduction into the microbiology of deep geological systems with a special focus on potential geobiotechnological applications and respective risk assessments. It has been known for decades that microbial activity is responsible for the degradation or conversion of hydrocarbons in oil, gas, and coal reservoirs. These processes occur in the absence of oxygen, a typical characteristic of such deep ecosystems. The understanding of the responsible microbial processes and their environmental regulation is not only of great scientific interest. It also has substantial economic and social relevance, inasmuch as these processes directly or indirectly affect the quantity and quality of the stored oil or gas. As outlined in the following chapter, in addition to the conventional hydrocarbons, new interest in such deep subsurface systems is rising for different technological developments. These are introduced together with related geomicrobiological topics. The capture and long-termed storage of large amounts of carbon dioxide, carbon capture and storage (CCS), for example, in depleted oil and gas reservoirs, is considered to be an important options to mitigate greenhouse gas emissions and global warming. On the other hand, the increasing contribution of energy from natural and renewable sources, such as wind, solar, geothermal energy, or biogas production leads to an increasing interest in underground storage of renewable energies. Energy carriers, that is, biogas, methane, or hydrogen, are often produced in a nonconstant manner and renewable energy may be produced at some distance from the place where it is needed. Therefore, storing the energy after its conversion to methane or hydrogen in porous reservoirs or salt caverns is extensively discussed. All these developments create new research fields and challenges for microbiologists and geobiotechnologists. As a basis for respective future work, we introduce the three major topics, that is