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Sample records for low-temperature geothermal potential

  1. Industrial low temperature utilization of geothermal resources

    Energy Technology Data Exchange (ETDEWEB)

    Howard, J.H.

    1976-05-01

    This brief presentation on industrial utilization of low temperature geothermal resources first considers an overview of what has been achieved in using geothermal resources in this way and, second, considers potential, future industrial applications.

  2. Potential of low-temperature geothermal resources in northern California. Report No. TR13

    Energy Technology Data Exchange (ETDEWEB)

    Hannah, J.L.

    1975-01-01

    Economically feasible uses for geothermal heat at temperatures too low for conventional electrical power generation at present are delineated. Several geothermal resource areas in northern California that have development potential are described, and applications of the heat found in each area are suggested. Plates are included of the following field study areas: the east side of the Sierra-Cascade Range north of Bishop, and the northern Coast Range from San Francisco Bay to Clear Lake. The counties included in the study area are Mo doc, Lassen, Sierra, Plumas, Placer, Alpine, Mono, Mendocino, Lake, and Sonoma. (LBS)

  3. Evaluation of low-temperature geothermal potential in north-central Box Elder County, Utah

    Energy Technology Data Exchange (ETDEWEB)

    Davis, M.C.; Kolesar, P.T.

    1984-12-01

    The low-temperature geothermal resources of north-central Box Elder County, Utah were assessed. Exploration techniques used included chemical analyses of water from wells and springs, temperature surveys, and temperature-depth measurements in unused wells within the study area. The highest water temperatures (31/sup 0/, 30/sup 0/, and 29/sup 0/C) recorded in this research were located in three separate geographic regions, suggesting that no single warm water occurrence dominates the study area. Total dissolved solid (TDS) concentrations ranged from 294 to 11,590 mg/l. Areas of warm water occurrences generally had TDS values of greater than 1100 mg/l. Reservoir temperatures were estimated using chemical geothermometers. Calculated temperatures ranged between 50/sup 0/ and 100/sup 0/C. Temperature-depth measurements were logged in 16 unused wells. Thermal gradients calculated from the profiles ranged from isothermal to 267/sup 0/C/km. The background gradient for the study area appears to be slightly above the average Basin and Range gradient of 35/sup 0/C/km. The highest gradients were calculated for the area approximately eight kilometers west of Snowville, Utah, which is also an area of warm water. 61 refs., 15 figs., 6 tabs.

  4. District space heating potential of low temperature hydrothermal geothermal resources in the southwestern United States. Technical report

    Energy Technology Data Exchange (ETDEWEB)

    McDevitt, P.K.; Rao, C.R.

    1978-10-01

    A computer simulation model (GIRORA-Nonelectric) is developed to study the economics of district space heating using geothermal energy. GIRORA-Nonelectric is a discounted cashflow investment model which evaluates the financial return on investment for space heating. This model consists of two major submodels: the exploration for and development of a geothermal anomaly by a geothermal producer, and the purchase of geothermal fluid by a district heating unit. The primary output of the model is a calculated rate of return on investment earned by the geothermal producer. The results of the sensitivity analysis of the model subject to changes in physical and economic parameters are given in this report. Using the results of the economic analysis and technological screening criteria, all the low temperature geothermal sites in Southwestern United States are examined for economic viability for space heating application. The methodology adopted and the results are given.

  5. Evaluation of low-temperature geothermal potential in Cache Valley, Utah. Report of investigation No. 174

    Energy Technology Data Exchange (ETDEWEB)

    de Vries, J.L.

    1982-11-01

    Field work consisted of locating 90 wells and springs throughout the study area, collecting water samples for later laboratory analyses, and field measurement of pH, temperature, bicarbonate alkalinity, and electrical conductivity. Na/sup +/, K/sup +/, Ca/sup +2/, Mg/sup +2/, SiO/sub 2/, Fe, SO/sub 4//sup -2/, Cl/sup -/, F/sup -/, and total dissolved solids were determined in the laboratory. Temperature profiles were measured in 12 additional, unused walls. Thermal gradients calculated from the profiles were approximately the same as the average for the Basin and Range province, about 35/sup 0/C/km. One well produced a gradient of 297/sup 0/C/km, most probably as a result of a near-surface occurrence of warm water. Possible warm water reservoir temperatures were calculated using both the silica and the Na-K-Ca geothermometers, with the results averaging about 50 to 100/sup 0/C. If mixing calculations were applied, taking into account the temperatures and silica contents of both warm springs or wells and the cold groundwater, reservoir temperatures up to about 200/sup 0/C were indicated. Considering measured surface water temperatures, calculated reservoir temperatures, thermal gradients, and the local geology, most of the Cache Valley, Utah area is unsuited for geothermal development. However, the areas of North Logan, Benson, and Trenton were found to have anomalously warm groundwater in comparison to the background temperature of 13.0/sup 0/C for the study area. The warm water has potential for isolated energy development but is not warm enough for major commercial development.

  6. Low-temperature geothermal potential of the Ojo Caliente warm springs area, northern New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Vuataz, F.D.; Stix, J.; Goff, F.; Pearson, C.F.

    1984-05-01

    A detailed geochemical investigation of 17 waters (thermal and cold, mineralized and dilute) was performed in the Ojo Caliente-La Madera area. Two types of thermomineral waters have separate and distinctive geologic, geochemical, and geothermal characteristics. The water from Ojo Caliente Resort emerges with temperatures less than or equal to 54/sup 0/C from a Precambrian metarhyolite. Its chemistry, typically Na-HCO/sub 3/, has a total mineralization of 3600 mg/l. Isotopic studies have shown that the thermal water emerges from the springs and a hot well without significant mixing with the cold shallow aquifer of the valley alluvium. However, the cold aquifer adjacent to the resort does contain varying amounts of thermal water that originates from the warm spring system. Geothermometry calculations indicate that the thermal water may be as hot as 85/sup 0/C at depth before its ascent toward surface. Thermodynamic computations on the reaction states of numerous mineral phases suggest that the thermal water will not cause major scaling problems if the hot water is utilized for direct-use geothermal applications. By means of a network of very shallow holes, temperature and electrical conductivity anomalies have been found elsewhere in the valley around Ojo Caliente, and resistivity soundings have confirmed the presence of a plume of thermal water entering the shallow aquifer. The group of lukewarm springs around La Madera, with temperatures less than or equal to 29/sup 0/C, chemical type of NaCaMg-HCO/sub 3/Cl and with a total mineralization less than or equal to 1500 mg/l behaves as a different system without any apparent relation to the Ojo Caliente system. Its temperature at depth is not believed to exceed 35 to 40/sup 0/C.

  7. The Socorro Geothermal System: A Low Temperature Geothermal Resource

    Science.gov (United States)

    Person, M. A.; Owens, L. B.

    2009-12-01

    The State of New Mexico is endowed with relatively high background heat flow and permeable, fractured crystalline and sedimentary rocks. This combination has given rise to numerous low temperature geothermal systems throughout the state. In many instances, hot springs associated with these systems are located within gaps in regional confining units (a.k.a. hydrologic windows) caused either by fault block rotation or the emplacement of volcanic dikes. The Socorro Geothermal Area (SGA) is a prime example of this type of a forced convection geothermal system. The Socorro geothermal area (SGA) lies 2 miles to the west of the NM Tech Campus near the base of the Socorro Mountain Block and will be assessed for production by drilling a 1500ft test well in September 2009. Published shallow temperature gradient measurements in fractured, permeable (3000 Darcy) granites indicate peak heat flow values as high as 490 mW/m^2 but decreases to 25 mW/m^2 about 10 km to the west within the La Jencia Basin near the foothills of the Magdalena Mountains. Silica and Cation based geothermometers suggest that deep geothermal reservoir reaches temperatures of 80 to 112 deg. C. Carbon14 age dating of shallow groundwater within the discharge area are about 20,000 years old. Hydrothermal models we constructed indicates that Mountain front recharge penetrates to depths of 4.5 km below the La Jencia Basin sedimentary pile into fractured, crystalline rocks. Discharge occurs through a hydrologic window to the east within a breached playa deposit at the western edge of the Socorro Basin. The hydrologic window was caused by fault block rotation. Warm springs which produce several hundred gpm of 32 deg. C water at the surface several miles to the south of the proposed drilling area also attest to the presence of a significant hydrothermal system. This low temperature resource could potentially heat the Campus of NM Tech.

  8. Analysis of Low-Temperature Utilization of Geothermal Resources

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Brian

    2015-06-30

    Full realization of the potential of what might be considered “low-grade” geothermal resources will require that we examine many more uses for the heat than traditional electricity generation. To demonstrate that geothermal energy truly has the potential to be a national energy source we will be designing, assessing, and evaluating innovative uses for geothermal-produced water such as hybrid biomass-geothermal cogeneration of electricity and district heating and efficiency improvements to the use of cellulosic biomass in addition to utilization of geothermal in district heating for community redevelopment projects. The objectives of this project were: 1) to perform a techno-economic analysis of the integration and utilization potential of low-temperature geothermal sources. Innovative uses of low-enthalpy geothermal water were designed and examined for their ability to offset fossil fuels and decrease CO2 emissions. 2) To perform process optimizations and economic analyses of processes that can utilize low-temperature geothermal fluids. These processes included electricity generation using biomass and district heating systems. 3) To scale up and generalize the results of three case study locations to develop a regionalized model of the utilization of low-temperature geothermal resources. A national-level, GIS-based, low-temperature geothermal resource supply model was developed and used to develop a series of national supply curves. We performed an in-depth analysis of the low-temperature geothermal resources that dominate the eastern half of the United States. The final products of this study include 17 publications, an updated version of the cost estimation software GEOPHIRES, and direct-use supply curves for low-temperature utilization of geothermal resources. The supply curves for direct use geothermal include utilization from known hydrothermal, undiscovered hydrothermal, and near-hydrothermal EGS resources and presented these results at the Stanford

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

    Science.gov (United States)

    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

  10. Low-temperature geothermal resources of Washington

    Energy Technology Data Exchange (ETDEWEB)

    Schuster, J.E. [Washington State Dept. of Natural Resources, Olympia, WA (United States). Div. of Geology and Earth Resources; Bloomquist, R.G. [Washington State Energy Office, Olympia, WA (United States)

    1994-06-01

    This report presents information on the location, physical characteristics, and water chemistry of low-temperature geothermal resources in Washington. The database includes 941 thermal (>20C or 68F) wells, 34 thermal springs, lakes, and fumaroles, and 238 chemical analyses. Most thermal springs occur in the Cascade Range, and many are associated with stratovolcanoes. In contrast, 97 percent of thermal wells are located in the Columbia Basin of southeastern Washington. Some 83.5 percent are located in Adams, Benton, Franklin, Grant, Walla Walla, and Yakima Counties. Yakima County, with 259 thermal wells, has the most. Thermal wells do not seem to owe their origin to local sources of heat, such as cooling magma in the Earth`s upper crust, but to moderate to deep circulation of ground water in extensive aquifers of the Columbia River Basalt Group and interflow sedimentary deposits, under the influence of a moderately elevated (41C/km) average geothermal gradient.

  11. 2014 Low-Temperature and Coproduced Geothermal Resources Fact Sheet

    Energy Technology Data Exchange (ETDEWEB)

    Tim Reinhardt, Program Manager

    2014-09-01

    As a growing sector of geothermal energy development, the Low-Temperature Program supports innovative technologies that enable electricity production and cascaded uses from geothermal resources below 300° Fahrenheit.

  12. An Estimate of Shallow, Low-Temperature Geothermal Resources of the United States

    Energy Technology Data Exchange (ETDEWEB)

    Mullane, Michelle; Gleason, Michael; Reber, Tim; McCabe, Kevin; Mooney, Meghan; Young, Katherine R.

    2017-05-01

    Low-temperature geothermal resources in the United States potentially hold an enormous quantity of thermal energy, useful for direct use in residential, commercial and industrial applications such as space and water heating, greenhouse warming, pool heating, aquaculture, and low-temperature manufacturing processes. Several studies published over the past 40 years have provided assessments of the resource potential for multiple types of low-temperature geothermal systems (e.g. hydrothermal convection, hydrothermal conduction, and enhanced geothermal systems) with varying temperature ranges and depths. This paper provides a summary and additional analysis of these assessments of shallow (= 3 km), low-temperature (30-150 degrees C) geothermal resources in the United States, suitable for use in direct-use applications. This analysis considers six types of geothermal systems, spanning both hydrothermal and enhanced geothermal systems (EGS). We outline the primary data sources and quantitative parameters used to describe resources in each of these categories, and present summary statistics of the total resources available. In sum, we find that low-temperature hydrothermal resources and EGS resources contain approximately 8 million and 800 million TWh of heat-in-place, respectively. In future work, these resource potential estimates will be used for modeling of the technical and market potential for direct-use geothermal applications for the U.S. Department of Energy's Geothermal Vision Study.

  13. Evaluation of low-temperature geothermal potential in Utah and Goshen Valleys and adjacent areas, Utah. Part I. Gravity survey

    Energy Technology Data Exchange (ETDEWEB)

    Davis, D.A.; Cook, K.L.

    1983-04-01

    During 1980 and 1981 a total of 569 new gravity stations were taken in Utah and Goshen Valleys and adjacent areas, Utah. The new stations were combined with 530 other gravity stations taken in previous surveys which resulted in a compilation of 1099 stations which were used in this study. The additional surveys were undertaken to assist in the evaluation of the area for the possible development of geothermal resources by providing an interpreted structural framework by delineating faults, structural trends, intrusions, thickness of valley fill, and increased density of host rock. The gravity data are presented as (1) a complete Bouguer gravity anomaly map with a 2 mgal contour interval on a scale of 1:100,000 and (2) five generally east-trending gravity profiles. A geologic interpretation of the study area was made from the gravity map and from the interpretive geologic cross sections which were modeled along the gravity profiles.

  14. 1992--1993 low-temperature geothermal assessment program, Colorada

    Energy Technology Data Exchange (ETDEWEB)

    Cappa, J.A.; Hemborg, H.T.

    1995-01-01

    Previous assessments of Colorado`s low-temperature geothermal resources were completed by the Colorado Geological Survey in 1920 and in the mid- to late-1970s. The purpose of the 1992--1993 low-temperature geothermal resource assessment is to update the earlier physical, geochemical, and utilization data and compile computerized databases of the location, chemistry, and general information of the low-temperature geothermal resources in Colorado. The main sources of the data included published data from the Colorado Geological Survey, the US Geological Survey WATSTOR database, and the files of the State Division of Water Resources. The staff of the Colorado Geological Survey in 1992 and 1993 visited most of the known geothermal sources that were recorded as having temperatures greater than 30{degrees}C. Physical measurements of the conductivity, pH, temperature, flow rate, and notes on the current geothermal source utilization were taken. Ten new geochemical analyses were completed on selected geothermal sites. The results of the compilation and field investigations are compiled into the four enclosed Quattro Pro 4 databases. For the purposes of this report a geothermal area is defined as a broad area, usually less than 3 sq mi in size, that may have several wells or springs. A geothermal site is an individual well or spring within a geothermal area. The 1992-1993 assessment reports that there are 93 geothermal areas in the Colorado, up from the 56 reported in 1978; there are 157 geothermal sites up from the 125 reported in 1978; and a total of 382 geochemical analyses are compiled, up from the 236 reported in 1978. Six geothermal areas are recommended for further investigation: Trimble Hot Springs, Orvis Hot Springs, an area southeast of Pagosa Springs, the eastern San Luis Valley, Rico and Dunton area, and Cottonwood Hot Springs.

  15. State-coupled low temperature geothermal resource assessment program, fiscal year 1982. Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Icerman, Larry

    1983-08-01

    This report summarizes the results of low-temperature geothermal energy resource assessment efforts in New Mexico during the period from June 15, 1981 through September 30, 1983, under the sponsorship of the US Department of Energy (Contract DE-AS07-78ID01717). The report is divided into four chapters which correspond to the tasks delineated in the contract. Chapter 5 is a brief summary of the tasks performed under this contract during the period October 1, 1978, through June 30, 1983. This work extends the knowledge of low-temperature geothermal reservoirs with the potential for direct heating applications in New Mexico. The research effort focused on compiling basic geothermal data throughout selected areas in New Mexico in a format suitable for direct transfer to the US Geological Survey for inclusion in the GEOTHERM data file and to the National Oceanic and Atmospheric Administration for use with New Mexico geothermal resources maps.

  16. Low-temperature Stirling Engine for Geothermal Electricity Generation

    Energy Technology Data Exchange (ETDEWEB)

    Stillman, Greg [Cool Energy, Inc., Boulder, CO (United States); Weaver, Samuel P. [Cool Energy, Inc., Boulder, CO (United States)

    2013-03-27

    Up to 2700 terawatt-hours per year of geothermal electricity generation capacity has been shown to be available within North America, typically with wells drilled into geologically active regions of the earth's crust where this energy is concentrated (Huttrer, 2001). Of this potential, about half is considered to have temperatures high enough for conventional (steam-based) power production, while the other half requires unconventional power conversion approaches, such as organic Rankine cycle systems or Stirling engines. If captured and converted effectively, geothermal power generation could replace up to 100GW of fossil fuel electric power generation, leading to a significant reduction of US power sector emissions. In addition, with the rapid growth of hydro-fracking in oil and gas production, there are smaller-scale distributed power generation opportunities in heated liquids that are co-produced with the main products. Since 2006, Cool Energy, Inc. (CEI) has designed, fabricated and tested four generations of low-temperature (100°C to 300°C) Stirling engine power conversion equipment. The electric power output of these engines has been demonstrated at over 2kWe and over 16% thermal conversion efficiency for an input temperature of 215°C and a rejection temperature of 15°C. Initial pilot units have been shipped to development partners for further testing and validation, and significantly larger engines (20+ kWe) have been shown to be feasible and conceptually designed. Originally intended for waste heat recovery (WHR) applications, these engines are easily adaptable to geothermal heat sources, as the heat supply temperatures are similar. Both the current and the 20+ kWe designs use novel approaches of self-lubricating, low-wear-rate bearing surfaces, non-metallic regenerators, and high-effectiveness heat exchangers. By extending CEI's current 3 kWe SolarHeart® Engine into the tens of kWe range, many additional applications are possible, as one

  17. Low Temperature Geothermal Resource Assessment for Membrane Distillation Desalination in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Akar, Sertac; Turchi, Craig

    2017-05-01

    Substantial drought and declines in potable groundwater in the United States over the last decade has increased the demand for fresh water. Desalination of saline water such as brackish surface or groundwater, seawater, brines co-produced from oil and gas operations, industrial wastewater, blow-down water from power plant cooling towers, and agriculture drainage water can reduce the volume of water that requires disposal while providing a source of high-quality fresh water for industrial or commercial use. Membrane distillation (MD) is a developing technology that uses low-temperature thermal energy for desalination. Geothermal heat can be an ideal thermal-energy source for MD desalination technology, with a target range of $1/m3 to $2/m3 for desalinated water depending on the cost of heat. Three different cases were analyzed to estimate levelized cost of heat (LCOH) for integration of MD desalination technology with low-grade geothermal heat: (1) residual heat from injection brine at a geothermal power plant, (2) heat from existing underutilized low-temperature wells, and (3) drilling new wells for low-temperature resources. The Central and Western United States have important low-temperature (<90 degrees C) geothermal resource potential with wide geographic distribution, but these resources are highly underutilized because they are inefficient for power production. According to the USGS, there are 1,075 identified low temperature hydrothermal systems, 55 low temperature sedimentary systems and 248 identified medium to high temperature geothermal systems in the United States. The estimated total beneficial heat potential from identified low temperature hydrothermal geothermal systems and residual beneficial heat from medium to high temperature systems is estimated as 36,300 MWth, which could theoretically produce 1.4 to 7 million m3/day of potable water, depending on desalination efficiency.

  18. California low-temperature geothermal resources update: 1993

    Energy Technology Data Exchange (ETDEWEB)

    Youngs, L.G.

    1994-12-31

    The US Department of Energy -- Geothermal Division (DOE/GD) recently sponsored the Low-Temperature Geothermal Resources and Technology Transfer Program to bring the inventory of the nation`s low- and moderate-temperature geothermal resources up to date and to encourage development of the resources. The Oregon Institute of Technology, Geo-Heat Center (OIT/GHC) and the University of Utah Research Institute (UURI) established subcontracts and coordinated the project with the state resource teams from the western states that participated in the program. The California Department of Conservation, Division of Mines and Geology (DMG) entered into contract numbered 1092--023(R) with the OIT/GHC to provide the California data for the program. This report is submitted in fulfillment of that contract.

  19. State-coupled low-temperature geothermal-resource assessment program, Fiscal Year 1979. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Icerman, L.; Starkey, A.; Trentman, N. (eds.)

    1980-10-01

    The results of low-temperature geothermal energy resource assessment efforts in New Mexico during the period from 1 October 1978 to 30 June 1980 are summarized. The results of the efforts to extend the inventory of geothermal energy resources in New Mexico to low-temperature geothermal reservoirs with the potential for direct heating applications are given. These efforts focused on compiling basic geothermal data and new hydrology and temperature gradient data throughout New Mexico in a format suitable for direct transfer to the US Geological Survey and the National Oceanic and Atmospheric Administration for inclusion in the GEOTHERM data file and for preparation of New Mexico low-temperature geothermal resources maps. The results of geothermal reservoir confirmation studies are presented. (MHR)

  20. Optimization of the Energy Conversion Starting from Low-Temperature Heat. Application to Geothermal Binary Cycles

    OpenAIRE

    2014-01-01

    Low-temperature geothermal heat sources can be found in many regions in the world, but despite their huge energetic potential, only a limited amount of these sources are used. These heat sources are in most cases not free and wells have to be drilled to access the geothermal heat. One injection well and one or more production wells are usually used and depths down to several kilometers are needed to obtain a temperature high enough to be useful. These deep geothermal wells are very expensive,...

  1. Optimization of the Energy Conversion Starting from Low-Temperature Heat. Application to Geothermal Binary Cycles

    OpenAIRE

    Walraven, Daniël

    2014-01-01

    Low-temperature geothermal heat sources can be found in many regions in the world, but despite their huge energetic potential, only a limited amount of these sources are used. These heat sources are in most cases not free and wells have to be drilled to access the geothermal heat. One injection well and one or more production wells are usually used and depths down to several kilometers are needed to obtain a temperature high enough to be useful. These deep geothermal wells are very expensive,...

  2. Integrated exploration for low-temperature geothermal resources in the Honey Lake Basin, California

    Science.gov (United States)

    Schimschal, U.

    1991-01-01

    An integrated exploration study is presented to locate low-temperature geothermal reservoirs in the Honey Lake area of northern California. Regional studies to locate the geothermal resources included gravity, infra-red, water-temperature, and water-quality analyses. Five anomalies were mapped from resistivity surveys. Additional study of three anomalies by temperature-gradient and seismic methods was undertaken to define structure and potential of the geothermal resource. The gravity data show a graben structure in the area. Seismic reflection data indicate faults associated with surface-resistivity and temperature-gradient data. The data support the interpretation that the shallow reservoirs are replenished along the fault zones by deeply circulating heated meteoric waters. -Author

  3. Investigation of Low-Temperature Geothermal Resources in the Sonoma Valley Area, California

    Energy Technology Data Exchange (ETDEWEB)

    Youngs, Leslie G.; Chapman, Rodger H.; Chase, Gordon W.; Bezore, Stephen P.; Majmundar, Hasu H.

    1983-01-01

    The Sonoma Valley area contains low-temperature geothermal resources (20 C {le} T {le} 90 C) having the potential for useful development. Sonoma Valley residents, local governments and institutions, private developers, and manufacturers may be able to utilize the geothermal resources as an alternate energy source. Historically, there have been at least six geothermal spring areas developed in the Sonoma Valley. Four of these (Boyes Hot Springs, Fetter's Hot Springs, Agua Caliente Springs, and the Sonoma State Hospital warm spring) lie on a linear trend extending northwestward from the City of Sonoma. Detailed geophysical surveys delineated a major fault trace along the east side of the Sonoma Valley in association with the historic geothermal areas. Other fault traces were also delineated revealing a general northwest-trending structural faulting fabric underlying the valley. Water wells located near the ''east side'' fault have relatively high boron concentrations. Geochemical evidence may suggest the ''east side'' fault presents a barrier to lateral fluid migration but is a conduit for ascending fluids. Fifteen of the twenty-nine geothermal wells or springs located from literature research or field surveys are located along or east of this major fault in a 10 km (6.2 miles) long, narrow zone. The highest recorded water temperature in the valley appears to be 62.7 C (145 F) at 137.2 meters (450 feet) in a well at Boyes Hot Springs. This is consistent with the geothermal reservoir temperature range of 52-77 C (126-171 F) indicated by geothermometry calculations performed on data from wells in the area. Interpretation of data indicates a low-temperature geothermal fluid upwelling or ''plume'', along the ''east side'' fault with subsequent migration into permeable aquifers predominantly within volcanic strata. It is quite likely other geothermal fluid &apos

  4. Optimization of the operation of a network of low temperature geothermal reservoirs

    OpenAIRE

    Hrannar Már Sigrúnarson 1975

    2013-01-01

    In 1930 the first low temperature geothermal reservoir was harvested in Reykjavik. In the decades that followed more reservoirs where harvested and in 1990 Nejsavellir power plant began operation and supplied hot water to Reykjavík. Today all hot water used in Reykjavík has it's source from low temperature geothermal reservoirs or power plants that heat up cold ground water with geothermal heat. Around Reykjavík there are four low temperature reservoirs and two power plants that produce water...

  5. Hybrid Cooling Systems for Low-Temperature Geothermal Power Production

    Energy Technology Data Exchange (ETDEWEB)

    Ashwood, A.; Bharathan, D.

    2011-03-01

    This paper describes the identification and evaluation of methods by which the net power output of an air-cooled geothermal power plant can be enhanced during hot ambient conditions with a minimal amount of water use.

  6. Use of Low-Temperature Geothermal Energy for Desalination in the Western United States

    Energy Technology Data Exchange (ETDEWEB)

    Turchi, Craig S. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Akar, Sertac [National Renewable Energy Lab. (NREL), Golden, CO (United States); Cath, Tzahi [Colorado School of Mines, Golden, CO (United States); Vanneste, Johan [Colorado School of Mines, Golden, CO (United States); Geza, Mengistu [Colorado School of Mines, Golden, CO (United States)

    2015-11-01

    This joint project between the National Renewable Energy Laboratory and the Colorado School of Mines has examined the potential of using low-temperature geothermal resources for desalination. The temperature range in question is not well suited for electricity generation, but can be used for direct heating. Accordingly, the best integration approaches use thermal desalination technologies such as multi-effect distillation (MED) or membrane distillation (MD), rather than electric-driven technologies such as reverse osmosis (RO). The examination of different desalination technologies led to the selection of MD for pairing with geothermal energy. MD operates at near-ambient pressure and temperatures less than 100°C with hydrophobic membranes. The technology is modular like RO, but the equipment costs are lower. The thermal energy demands of MD are higher than MED, but this is offset by an ability to run at lower temperatures and a low capital cost. Consequently, a geothermal-MD system could offer a low capital cost and, if paired with low-cost geothermal energy, a low operating cost. The target product water cost is $1.0 to $1.5 per cubic meter depending on system capacity and the cost of thermal energy.

  7. Data acquisition for low-temperature geothermal well tests and long-term monitoring. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Lienau, P.J.

    1992-09-01

    Groundwater monitoring is an essential part of the development of a low-temperature geothermal field for production and injection wells. State water resource and environmental departments are requiring both geothermal well testing and long-term monitoring as a part of the permitting process for geothermal developments. This report covers water-level measurement methods, instruments used for well testing, geochemical sampling, examples of data acquisition and regulatory mandates on groundwater monitoring.

  8. Data acquisition for low-temperature geothermal well tests and long-term monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Lienau, P.J.

    1992-09-01

    Groundwater monitoring is an essential part of the development of a low-temperature geothermal field for production and injection wells. State water resource and environmental departments are requiring both geothermal well testing and long-term monitoring as a part of the permitting process for geothermal developments. This report covers water-level measurement methods, instruments used for well testing, geochemical sampling, examples of data acquisition and regulatory mandates on groundwater monitoring.

  9. Data Acquisition for Low-Temperature Geothermal Well Tests and Long-Term Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Lienau, P.J.

    1992-03-01

    Groundwater monitoring is an essential part of the development of a low-temperature geothermal field for production and injection wells. State water resource and environmental departments are requiring both geothermal well testing and long-term monitoring as a part of the permitting process for geothermal developments. This report covers water-level measurement methods, instruments used for well testing, geochemical sampling, examples of data acquisition and regulatory mandates on groundwater monitoring.

  10. Economic study of low temperature geothermal energy in Lassen and Modoc counties, California

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-04-01

    The purpose of this study was to investigate the feasibility of using low cost, low temperature geothermal energy in job-producing industries to increase employment and encourage economic development. The study, encompassing all of Lassen and modoc Counties, was to be site-specific, referencing candidate geothermal applications to known hot wells and springs as previously determined, or to new wells with specific characteristics as defined in the Scope of Work. The emphasis was to be placed on economically practical and readily achievable applications from known resources, thus complimenting the recently completed ERDA-Susanville Study where a designated community was used as a ''laboratory'' in which land-use planning, institutional aspects, geological assessments, technical modeling and socioeconomic impacts were all examined in overview. During the course of the study, monthly progress reports were prepared and reviewed with the Commission so that emphasis on particular features of study could be changed as necessary to reflect updated findings and to redirect efforts into additional areas of potential promise as they became apparent. In this manner, a degree of flexibility was maintained which allowed a more comprehensive study than would have been otherwise possible. Although the report generates both positive and negative findings in specific areas of investigation, it is felt that the overall long term prognosis for geothermal energy stimulus to industry in the area is excellent.

  11. Transported Low-Temperature Geothermal Energy for Thermal End Uses Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Zhiyao [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Liu, Xiaobing [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gluesenkamp, Kyle R [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Mehdizadeh Momen, Ayyoub [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Li, Jan-Mou [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-10-01

    The use of geothermal energy is an emerging area for improving the nation’s energy resiliency. Conventionally, geothermal energy applications have focused on power generation using high temperature hydrothermal resources or enhanced geothermal systems. However, many low temperature (below 150°C/300°F) geothermal resources are also available but have not been fully utilized. For example, it is estimated that 25 billion barrels of geothermal fluid (mostly water and some dissolved solids) at 176°F to 302°F (80°C to 150°C) is coproduced annually at oil and gas wells in the United States (DOE 2015). The heat contained in coproduced geothermal fluid (also referred as “coproduced water”) is typically wasted because the fluid is reinjected back into the ground without extracting the heat.

  12. Scale Resistant Heat Exchanger for Low Temperature Geothermal Binary Cycle Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Hays, Lance G. [Energent Corporation, Santa Ana, CA (United States)

    2014-11-18

    Phase 1 of the investigation of improvements to low temperature geothermal power systems was completed. The improvements considered were reduction of scaling in heat exchangers and a hermetic turbine generator (eliminating seals, seal system, gearbox, and lube oil system). A scaling test system with several experiments was designed and operated at Coso geothermal resource with brine having a high scaling potential. Several methods were investigated at the brine temperature of 235 ºF. One method, circulation of abradable balls through the brine passages, was found to substantially reduce scale deposits. The test heat exchanger was operated with brine outlet temperatures as low as 125 ºF, which enables increased heat input available to power conversion systems. For advanced low temperature cycles, such as the Variable Phase Cycle (VPC) or Kalina Cycle, the lower brine temperature will result in a 20-30% increase in power production from low temperature resources. A preliminary design of an abradable ball system (ABS) was done for the heat exchanger of the 1 megawatt VPC system at Coso resource. The ABS will be installed and demonstrated in Phase 2 of this project, increasing the power production above that possible with the present 175 ºF brine outlet limit. A hermetic turbine generator (TGH) was designed and manufacturing drawings produced. This unit will use the working fluid (R134a) to lubricate the bearings and cool the generator. The 200 kW turbine directly drives the generator, eliminating a gearbox and lube oil system. Elimination of external seals eliminates the potential of leakage of the refrigerant or hydrocarbon working fluids, resulting in environmental improvement. A similar design has been demonstrated by Energent in an ORC waste heat recovery system. The existing VPC power plant at Coso was modified to enable the “piggyback” demonstration of the TGH. The existing heat exchanger, pumps, and condenser will be operated to provide the required

  13. Advanced Low Temperature Geothermal Power Cycles (The ENTIV Organic Project) Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Mugerwa, Michael [Technip USA, Inc., Claremont, CA (United States)

    2015-11-18

    Feasibility study of advanced low temperature thermal power cycles for the Entiv Organic Project. Study evaluates amonia-water mixed working fluid energy conversion processes developed and licensed under Kalex in comparison with Kalina cycles. Both cycles are developed using low temperature thermal resource from the Lower Klamath Lake Geothermal Area. An economic feasibility evaluation was conducted for a pilot plant which was deemed unfeasible by the Project Sponsor (Entiv).

  14. Companion Study Guide to Short Course on Geothermal Corrosion and Mitigation in Low Temperature Geothermal Heating Systems

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, P.F. II

    1985-04-24

    The economic utilization of geothermal resources with temperatures less than 220 degrees Fahrenheit for purposes other than electric power generation (direct utilization) requires creation of systems with long plant life and minimum operation and maintenance costs. Development of such systems requires careful corrosion engineering if the most cost effective material selections and design choices are to be made. This study guide presents guidelines for materials selection for low-temperature geothermal systems (120 - 200 degrees Fahrenheit), as well as guidance in materials design of heat pump systems for very-lowtemperature geothermal resources (less than 120 degrees Fahrenheit). This guideline is divided into five sections and an Appendix.

  15. Reservoir engineering assessment of low-temperature geothermal resources in the Skierniewice municipality (Poland)

    Energy Technology Data Exchange (ETDEWEB)

    Battistelli, Alfredo [Aquater SpA, ENI Group, S. Lorenzo in Campo (Italy); Nagy, Stanislaw [Univ. of Mining and Metallurgy, Drilling and Petroleum Engineering Dept., Krakow (Poland)

    2000-12-01

    Low temperature geothermal resources and their production potential in the Skierniewice area of Poland were evaluated assuming conventional well doublet arrays. The reservoir engineering assessment was carried out, within the framework of a World Bank project, to study the feasibility of providing heat to the local district heating system, using data from two existing wells and from geophysical surveys, and by evaluating results of production, injection and interference well tests. Two options were simulated mathematically, using both semianalytical and numerical codes, considering a simplified reservoir model: one based on the two existing wells, the other considering four wells, two to be drilled. The injection of spent brines into a different reservoir was also studied. (Author)

  16. A study on modeling and performance assessment of a heat pump system for utilizing low temperature geothermal resources in buildings

    Energy Technology Data Exchange (ETDEWEB)

    Hepbasli, Arif [Department of Mechanical Engineering, Faculty of Engineering, Ege University, 35100 Bornova, Izmir (Turkey); Tolga Balta, M. [Department of Mechanical Engineering, Aksaray Engineering Faculty, Nigde University, 68100 Aksaray (Turkey)

    2007-10-15

    Low and moderate geothermal resources are found in most areas of the world. A very efficient way to heat and air-condition homes and buildings is the utilization of ground source heat pumps (GSHPs), also known as geothermal heat pump (GHPs), to obtain heat energy from low temperature geothermal resources. The present study deals with the modeling and performance evaluation of a heat pump system utilizing a low temperature geothermal resource, which is approximated to a geothermal reservoir. The system was designed, constructed and tested in Nigde University, Nigde, Turkey and has been successfully operated since 2005. Energy and exergy analysis methods were used to assess the system performance based on the experimental data. Exergy destructions (or irreversibilities) as well as energy and exergy efficiency relations were presented for each component of the heat pump unit and the whole system, while some thermodynamic parameters, such as fuel depletion ratio, relative irreversibility, productivity lack, exergetic factor and improvement potential, were investigated for the system. Energy and exergy efficiency values on a product/fuel basis were found to range from 73.9% to 73.3% and 63.3% to 51.7% at dead (reference) state temperatures varying from 0 to 25 C for the heat pump unit and entire system, respectively. It is expected that the model presented here would be beneficial to the researchers, government administration, and engineers working in the area of heat pump systems for residential applications. (author)

  17. Demonstration of a Variable Phase Turbine Power System for Low Temperature Geothermal Resources

    Energy Technology Data Exchange (ETDEWEB)

    Hays, Lance G

    2014-07-07

    A variable phase turbine assembly will be designed and manufactured having a turbine, operable with transcritical, two-phase or vapor flow, and a generator – on the same shaft supported by process lubricated bearings. The assembly will be hermetically sealed and the generator cooled by the refrigerant. A compact plate-fin heat exchanger or tube and shell heat exchanger will be used to transfer heat from the geothermal fluid to the refrigerant. The demonstration turbine will be operated separately with two-phase flow and with vapor flow to demonstrate performance and applicability to the entire range of low temperature geothermal resources. The vapor leaving the turbine is condensed in a plate-fin refrigerant condenser. The heat exchanger, variable phase turbine assembly and condenser are all mounted on single skids to enable factory assembly and checkout and minimize installation costs. The system will be demonstrated using low temperature (237F) well flow from an existing large geothermal field. The net power generated, 1 megawatt, will be fed into the existing power system at the demonstration site. The system will demonstrate reliable generation of inexpensive power from low temperature resources. The system will be designed for mass manufacturing and factory assembly and should cost less than $1,200/kWe installed, when manufactured in large quantities. The estimated cost of power for 300F resources is predicted to be less than 5 cents/kWh. This should enable a substantial increase in power generated from low temperature geothermal resources.

  18. Economic study of low temperature geothermal energy in Lassen and Modoc Counties, California

    Energy Technology Data Exchange (ETDEWEB)

    1977-04-01

    The feasibility of using low cost, low temperature geothermal energy in job-producing industries to increase employment and encourage economic development was investigated. The study, encompassing all of Lassen and Modoc Counties, was to be site-specific, referencing candidate geothermal applications to known hot wells and springs as previously determined, or to new wells with specific characteristics as defined in the Scope of Work. The emphasis was to be placed on economically practical and readily achievable applications from known resources. Although both positive and negative findings were found in specific areas of investigation, it is felt that the overall long term prognosis for geothermal energy stimulus to industry in the area is excellent. The applications studied were; greenhouse heating, kiln drying, onion dehydration, feedlots, and aquaculture.

  19. Low-temperature geothermal assessment of the Santa Clara and Virgin River Valleys, Washington County, Utah

    Energy Technology Data Exchange (ETDEWEB)

    Budding, K.E.; Sommer, S.N.

    1986-01-01

    Exploration techniques included the following: (1) a temperature survey of springs, (2) chemical analyses and calculated geothermometer temperatures of water samples collected from selected springs and wells, (3) chemical analyses and calculated geothermometer temperatures of spring and well water samples in the literature, (4) thermal gradients measured in accessible wells, and (5) geology. The highest water temperature recorded in the St. George basin is 42/sup 0/C at Pah Tempe Hot Springs. Additional spring temperatures higher than 20/sup 0/C are at Veyo Hot Spring, Washington hot pot, and Green Spring. The warmest well water in the study area is 40/sup 0/C in Middleton Wash. Additional warm well water (higher than 24.5/sup 0/C) is present north of St. George, north of Washington, southeast of St. George, and in Dameron Valley. The majority of the Na-K-Ca calculated reservoir temperatures range between 30/sup 0/ and 50/sup 0/C. Anomalous geothermometer temperatures were calculated for water from Pah Tempe and a number of locations in St. George and vicinity. In addition to the known thermal areas of Pah Tempe and Veyo Hot Spring, an area north of Washington and St. George is delineated in this study to have possible low-temperature geothermal potential.

  20. GIS to support cost-effective decisions on renewable sources applications for low temperature geothermal energy

    CERN Document Server

    Gemelli, Alberto; Diamantini, Claudia; Longhi, Sauro

    2013-01-01

    Through the results of a developed case study of information system for low temperature geothermal energy, GIS to Support Cost-effective Decisions on Renewable Sources addresses the issue of the use of Geographic Information Systems (GIS) in evaluating cost-effectiveness of renewable resource exploitation regional scale. Focusing on the design of a Decision Support System, a process is presented aimed to transform geographic data into knowledge useful for analysis and decision-making on the economic exploitation of geothermal energy. This detailed description includes a literature review and technical issues related to data collection, data mining, decision analysis for the informative system developed for the case study. A multi-disciplinary approach to GIS design is presented which is also an innovative example of fusion of georeferenced data acquired from multiple sources including remote sensing, networks of sensors and socio-economic censuses. GIS to Support Cost-effective Decisions on Renewable Sources ...

  1. Exergy analysis of the performance of low-temperature district heating system with geothermal heat pump

    Directory of Open Access Journals (Sweden)

    Sekret Robert

    2014-03-01

    Full Text Available Exergy analysis of low temperature geothermal heat plant with compressor and absorption heat pump was carried out. In these two concepts heat pumps are using geothermal water at 19.5 oC with spontaneous outflow 24 m3/h as a heat source. The research compares exergy efficiency and exergy destruction of considered systems and its components as well. For the purpose of analysis, the heating system was divided into five components: geothermal heat exchanger, heat pump, heat distribution, heat exchanger and electricity production and transportation. For considered systems the primary exergy consumption from renewable and non-renewable sources was estimated. The analysis was carried out for heat network temperature at 50/40 oC, and the quality regulation was assumed. The results of exergy analysis of the system with electrical and absorption heat pump show that exergy destruction during the whole heating season is lower for the system with electrical heat pump. The exergy efficiencies of total system are 12.8% and 11.2% for the system with electrical heat pump and absorption heat pump, respectively.

  2. Effective potentials for atom-atom interaction at low temperatures

    OpenAIRE

    Gao, Bo

    2002-01-01

    We discuss the concept and design of effective atom-atom potentials that accurately describe any physical processes involving only states around the threshold. The existence of such potentials gives hope to a quantitative, and systematic, understanding of quantum few-atom and quantum many-atom systems at relatively low temperatures.

  3. Design and optimization of organic rankine cycle for low temperature geothermal power plant

    Science.gov (United States)

    Barse, Kirtipal A.

    Rising oil prices and environmental concerns have increased attention to renewable energy. Geothermal energy is a very attractive source of renewable energy. Although low temperature resources (90°C to 150°C) are the most common and most abundant source of geothermal energy, they were not considered economical and technologically feasible for commercial power generation. Organic Rankine Cycle (ORC) technology makes it feasible to use low temperature resources to generate power by using low boiling temperature organic liquids. The first hypothesis for this research is that using ORC is technologically and economically feasible to generate electricity from low temperature geothermal resources. The second hypothesis for this research is redesigning the ORC system for the given resource condition will improve efficiency along with improving economics. ORC model was developed using process simulator and validated with the data obtained from Chena Hot Springs, Alaska. A correlation was observed between the critical temperature of the working fluid and the efficiency for the cycle. Exergy analysis of the cycle revealed that the highest exergy destruction occurs in evaporator followed by condenser, turbine and working fluid pump for the base case scenarios. Performance of ORC was studied using twelve working fluids in base, Internal Heat Exchanger and turbine bleeding constrained and non-constrained configurations. R601a, R245ca, R600 showed highest first and second law efficiency in the non-constrained IHX configuration. The highest net power was observed for R245ca, R601a and R601 working fluids in the non-constrained base configuration. Combined heat exchanger area and size parameter of the turbine showed an increasing trend as the critical temperature of the working fluid decreased. The lowest levelized cost of electricity was observed for R245ca followed by R601a, R236ea in non-constrained base configuration. The next best candidates in terms of LCOE were R601a, R

  4. Low-temperature geothermal resource and stratigraphy of portions of Yakima County, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Biggane, J.

    1982-07-30

    The low-temperature geothermal resource of portions of Yakima County, south-central Washington, is defined by several least squares linear regression analyses of bottom-hole temperature and depth data. Bottom-hole temperature and depth data were separated into fourteen well data groups based on geographic proximity, land slope azimuth, and position within the regional ground-water flow system. The depths of these wells range from over 50m to almost 600m. The regression analyses of these well data groups indicate that the projected land-surface temperature and geothermal gradient range from 10.6 to 14.0/sup 0/C and from 24.9 to 52.2/sup 0/C/km, respectively. Stratigraphic correlation diagrams developed from borehole geophysical and lithologic logs are given for localities within the lower Yakima, Black Rock, Moxee, Ahtanum, Cowiche, and Naches valleys. These correlation diagrams are combined with their respective borehole temperature logs and well data group predicted temperature curves to assess the validity of the regression analyses and to determine aquifer locations, temperatures, and directions of intra-borehole flow. A regression analysis of data from wells of south-central Washington with bottom-hole depths of over 700m to almost 3km suggests that the projected land-surface temperature and geothermal gradient of this depth interval are 21.8/sup 0/C and 31.3/sup 0/C/km, respectively. The depth to the 100/sup 0/C isotherm is approximately 2513m.

  5. Selected data for low-temperature (less than 90{sup 0}C) geothermal systems in the United States: reference data for US Geological Survey Circular 892

    Energy Technology Data Exchange (ETDEWEB)

    Reed, M.J.; Mariner, R.H.; Brook, C.A.; Sorey, M.L.

    1983-12-15

    Supporting data are presented for the 1982 low-temperature geothermal resource assessment of the United States. Data are presented for 2072 geothermal sites which are representative of 1168 low-temperature geothermal systems identified in 26 States. The low-temperature geothermal systems consist of 978 isolated hydrothermal-convection systems, 148 delineated-area hydrothermal-convection systems, and 42 delineated-area conduction-dominated systems. The basic data and estimates of reservoir conditions are presented for each geothermal system, and energy estimates are given for the accessible resource base, resource, and beneficial heat for each isolated system.

  6. CO/sub 2/-silica geothermometer for low temperature geothermal resource assessment, with application to resources in the Safford Basin, Arizona

    Energy Technology Data Exchange (ETDEWEB)

    Witcher, J.C.; Stone, C.

    1983-11-01

    This study investigates silica-water reactions in low-temperature geothermal water in areas near Safford, southeastern Arizona, and derives a pCO2 correction for conductive silica geothermometers. Use and limitations of the technique are also discussed. Data collection, interpretation approach, and basic geochemistry, as it applies to this study, are outlined. In addition, the geology, thermal regime, geohydrology, and gross geochemistry of the Safford area are reviewed. Finally, geothermal potential, as indicated by this study and previous studies is discussed.

  7. Low Temperature Geothermal Play Fairway Analysis For The Appalachian Basin: Phase 1 Revised Report November 18, 2016

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, Teresa E. [Cornell Univ., Ithaca, NY (United States); Richards, Maria C. [Southern Methodist Univ., Dallas, TX (United States); Horowitz, Franklin G. [Cornell Univ., Ithaca, NY (United States); Camp, Erin [Cornell Univ., Ithaca, NY (United States); Smith, Jared D. [Cornell Univ., Ithaca, NY (United States); Whealton, Calvin A. [Cornell Univ., Ithaca, NY (United States); Stedinger, Jery R. [Cornell Univ., Ithaca, NY (United States); Hornbach, Matthew J. [Southern Methodist Univ., Dallas, TX (United States); Frone, Zachary S. [Southern Methodist Univ., Dallas, TX (United States); Tester, Jefferson W. [Cornell Univ., Ithaca, NY (United States); Anderson, Brian [West Virginia Univ., Morgantown, WV (United States); Welcker, Kelydra [West Virginia Univ., Morgantown, WV (United States); Chickering Pace, Catherine [Southern Methodist Univ., Dallas, TX (United States); He, Xiaoning [West Virginia Univ., Morgantown, WV (United States); Magnani, Maria Beatrice [Southern Methodist Univ., Dallas, TX (United States); Bolat, Rahmi [Southern Methodist Univ., Dallas, TX (United States)

    2016-11-18

    Geothermal energy is an attractive sustainable energy source. Yet project developers need confirmation of the resource base to warrant their time and financial resources. The Geothermal Play Fairway Analysis of the Appalachian Basin evaluated risk metrics that communicate the favorability of potential low-temperature geothermal energy resources in reservoirs more than 1000 m below the surface. This analysis is focused on the direct use of the heat, rather than on electricity production. Four risk factors of concern for direct-use geothermal plays in the Appalachian Basin portions of New York, Pennsylvania, and West Virginia are examined individually, and then in combination: 1) thermal resource quality, 2) natural reservoir quality, 3) induced seismicity, and 4) utilization opportunities. Uncertainty in the risk estimation is quantified. Based on these metrics, geothermal plays in the Appalachian Basin were identified as potentially viable for a variety of direct-use-heat applications. The methodologies developed in this project may be applied in other sedimentary basins as a foundation for low temperature (50-150 °C), direct use geothermal resource, risk, and uncertainty assessment. Three methods with which to combine the four risk factors were used. Among these, the averaging of the individual risk factors indicates the most favorable counties within the study area are the West Virginia counties of Monongalia, Harrison, Lewis (dubbed the Morgantown–Clarksburg play fairway), Putnam, and Kanawha (Charleston play fairway), the New York counties of Chemung and Steuben plus adjacent Bradford county in Pennsylvania (Corning–Ithaca play fairway), and the Pennsylvania counties of Mercer, Crawford, Erie, and Warren, and adjacent Chautauqua county in New York (together, the Meadville–Jamestown play fairway). These higher priority regions are surrounded by broader medium priority zones. Also worthy of additional exploration is a broad region near Pittsburgh

  8. Enabling CCS via Low-temperature Geothermal Energy Integration for Fossil-fired Power Generation

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, C. L.; Heldebrant, D. J.; Bearden, M. D.; Horner, J. A.; Freeman, C. J.

    2017-07-01

    Among the key barriers to commercial scale deployment is the cost associated with CO2 capture. This is particularly true for existing large, fossil-fired assets that account for a large fraction of the electricity generation fleet in developed nations, including the U.S. Fitting conventional combustion technologies with CO2 capture systems can carry an energy penalty of thirty percent or more, resulting in an increased price of power to the grid, as well as an overall decrease in net plant output. Taken together with the positive growth in demand for electricity, this implies a need for accelerated capital build-out in the power generation markets to accommodate both demand growth and decreased output at retrofitted plants. In this paper, the authors present the results of a study to assess the potential to use geothermal energy to provide boiler feedwater preheating, capturing efficiency improvements designed to offset the losses associated with CO2 capture. Based on NETL benchmark cases and subsequent analysis of the application using site-specific data from the North Valmy power plant, several cases for CO2 capture were evaluated. These included geothermally assisted MEA capture, CO2BOLs capture, and stand-alone hybrid power generation, compared with a baseline, no-geothermal case. Based on Case 10, and assuming 2.7 MMlb/h of geothermally sourced 150 ºC water, the parasitic power load associated with MEA capture could be offset by roughly seven percent, resulting in a small (~1 percent) overall loss to net power generation, but at levelized costs of electricity similar to the no-geothermal CCS case. For the CO2BOLs case, the availability of 150°C geothermal fluid could allow the facility to not only offset the net power decrease associated with CO2BOLs capture alone, but could increase nameplate capacity by two percent. The geothermally coupled CO2BOLs case also decreases LCOE by 0.75 ¢/kWh relative to the non-hybrid CO2BOLs case, with the improved

  9. Hydrochemistry and geothermometrical modeling of low-temperature Panticosa geothermal system (Spain)

    Science.gov (United States)

    Asta, Maria P.; Gimeno, Maria J.; Auqué, Luis F.; Gómez, Javier; Acero, Patricia; Lapuente, Pilar

    2012-08-01

    The chemical characteristics of the low-temperature geothermal system of Panticosa (Spain) were investigated in order to determine the water temperature at the reservoir and to identify the main geochemical processes that affect the water composition during the ascent of the thermal waters. In general, the studied waters are similar to other geothermal systems in the Pyrenees, belonging to the group of granite-related alkaline thermal waters (high pH, low total dissolved solids, very low magnesium concentration, and sodium as the dominant cation). According to the alkaline pH of these waters, they have a very low CO2 partial pressure, bicarbonate is the dominant anion and silica is partially ionized as H3SiO4-. The unusually active acid-base pairs (HCO3-/CO32 - and, mainly, H4SiO4/H3SiO4-) act as homogeneous pH buffers and contribute to the total alkalinity in these alkaline waters. On the basis of the study of the conservative elements, a mixing process between a hot and a cold end-member has been identified. Additionally, in order to determinate the water temperature at the reservoir, several geothermometric techniques have been applied, including both geothermometrical modeling and classical geothermometrical calculations. The geothermometrical modeling seems to indicate that thermal waters re-equilibrate with respect to calcite and kaolinite during their ascent to the surface. Modeling results suggest that these thermal waters would be in equilibrium with respect to albite, K-feldspar, quartz, calcite, kaolinite and zoisite at a similar temperature of 90 ± 20 °C in the reservoir, which is in good agreement with the results obtained by applying the classical geothermometers.

  10. State-coupled low-temperature geothermal-resource-assessment program, Fiscal Year 1980. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Icerman, L.; Starkey, A.; Trentman, N. (eds.)

    1981-08-01

    Magnetic, gravity, seismic-refraction, and seismic-reflection profiles across the Las Alturas Geothermal Anomaly, New Mexico, are presented. Studies in the Socorro area include the following: seismic measurements of the tertiary fill in the Rio Grande Depression west of Socorro, geothermal data availability for computer simulation in the Socorro Peak KGRA, and ground water circulation in the Socorro Geothermal Area. Regional geothermal exploration in the Truth or Consequences Area includes: geological mapping of the Mud Springs Mountains, hydrogeology of the thermal aquifer, and electrical-resistivity investigation of the geothermal potential. Other studies included are: geothermal exploration with electrical methods near Vado, Chamberino, and Mesquite; a heat-flow study of Dona Ana County; preliminary heat-flow assessment of Southeast Luna County; active fault analysis and radiometric dating of young basalts in southern New Mexico; and evaluation of the geothermal potential of the San Juan Basin in northwestern New Mexico.

  11. Low-Temperature Projects of the Department of Energy's Geothermal Technologies Program: Evaluation and Lessons Learned

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Tom; Snyder, Neil; Gosnold, Will

    2016-10-23

    This paper discusses opportunities and challenges related to the technical and economic feasibility of developing power generation from geothermal resources at temperatures of 150 degrees C and lower. Insights from projects funded by the U.S. Department of Energy (DOE), Geothermal Technologies Office inform these discussions and provide the basis for some lessons learned to help guide decisions by DOE and the industry in further developing this resource. The technical basis for low-temperature geothermal energy is well established and the systems can be economic today in certain situations. However, these applications are far from a 'plug and play' product; successful development today requires a good knowledge of geothermal system design and operation.

  12. Low-Temperature Projects of the Department of Energy's Geothermal Technologies Program: Evaluation and Lessons Learned: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Tom; Snyder, Neil; Gosnold, Will

    2016-12-01

    This paper discusses opportunities and challenges related to the technical and economic feasibility of developing power generation from geothermal resources at temperatures of 150 degrees C and lower. Insights from projects funded by the U.S. Department of Energy (DOE), Geothermal Technologies Office inform these discussions and provide the basis for some lessons learned to help guide decisions by DOE and the industry in further developing this resource. The technical basis for low-temperature geothermal energy is well established and the systems can be economic today in certain situations. However, these applications are far from a 'plug and play' product; successful development today requires a good knowledge of geothermal system design and operation.

  13. Low-temperature geothermal water in Utah: A compilation of data for thermal wells and springs through 1993

    Energy Technology Data Exchange (ETDEWEB)

    Blackett, R.E.

    1994-07-01

    The Geothermal Division of DOE initiated the Low-Temperature Geothermal Resources and Technology Transfer Program, following a special appropriation by Congress in 1991, to encourage wider use of lower-temperature geothermal resources through direct-use, geothermal heat-pump, and binary-cycle power conversion technologies. The Oregon Institute of Technology (OIT), the University of Utah Research Institute (UURI), and the Idaho Water Resources Research Institute organized the federally-funded program and enlisted the help of ten western states to carry out phase one. This first phase involves updating the inventory of thermal wells and springs with the help of the participating state agencies. The state resource teams inventory thermal wells and springs, and compile relevant information on each sources. OIT and UURI cooperatively administer the program. OIT provides overall contract management while UURI provides technical direction to the state teams. Phase one of the program focuses on replacing part of GEOTHERM by building a new database of low- and moderate-temperature geothermal systems for use on personal computers. For Utah, this involved (1) identifying sources of geothermal date, (2) designing a database structure, (3) entering the new date; (4) checking for errors, inconsistencies, and duplicate records; (5) organizing the data into reporting formats; and (6) generating a map (1:750,000 scale) of Utah showing the locations and record identification numbers of thermal wells and springs.

  14. Potential of geothermal systems in Picardy

    OpenAIRE

    Dourlat, Estelle

    2017-01-01

    Geothermal systems are not only about electrical plants or urban heating networks, but also concerned with geothermal energy assisted with a heat pump. In the former region of Picardy (North of France), 97% of the territory is suitable for very low temperature geothermal power. The French Agency for the Environment and Energy Management and the Picardy Region decided in 2016 to finance a facilitator to encourage geothermal use. To carry out this aim, it is important to consider the geothermal...

  15. Working fluids of a low-temperature geothermally-powered Rankine cycle for combined power and heat generation system

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A novel combined power and heat generation system was investigated in this study. This system consists of a low-temperature geothermally-powered organic Rankine cycle (ORC) subsystem, an intermediate heat exchanger and a commercial R134a-based heat pump subsystem. The advantages of the novel combined power and heat generation system are free of using additional cooling water circling system for the power generation subsystem as well as maximizing the use of thermal energy in the low-temperature geothermal source. The main purpose is to identify suitable working fluids (wet, isentropic and dry flu-ids) which may yield high PPR (the ratio of power produced by the power generation subsystem to power consumed by the heat pump subsystem) value and QQR (the ratio of heat supplied to the user to heat produced by the geothermal source) value. Parameters under investigation were evaporating temperature, PPR value and QQR value. Results indicate that there exits an optimum evaporating temperature to maximize the PPR value and minimize the QQR value at the same time for individual fluid. And dry fluids show higher PPR values but lower QQR values. NH3 and R152a outstand among wet fluids. R134a out-stands among isentropic fluids. R236ea, R245ca, R245fa, R600 and R600a outstand among dry fluids. R236ea shows the highest PPR value among the recommended fluids.

  16. Hydrologic Windows and the Formation of Low-Temperature Geothermal Anomalies along the Rio Grande Rift, New Mexico

    Science.gov (United States)

    Pepin, J.; Person, M. A.; Kelley, S.; Timmons, S.; Owens, L.; Witcher, J. C.; Phillips, F. M.; Gable, C. W.; Coblentz, D. D.; Campbell, A.

    2013-12-01

    overlying Paleozoic sedimentary rocks. This implies that the permeability of the crystalline basement must be relatively high (between 10 to 1000 mD) in order to permit such deep circulation of groundwater. Hydrologic windows in overlying sediments then serve as conduits for these fluids to surface relatively rapidly. This phenomenon results in less cooling of the fluids as they rise to surface, thereby allowing the formation of surficial low-temperature geothermal systems. It is then apparent that where some hydrologic windows occur, groundwater circulation is not confined to the basin fill and crystalline basement permeability approaches or exceeds values typically assigned to shallower unconfined aquifers.

  17. Modeling of thermodynamic and chemical changes in low-temperature geothermal systems

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, A.L.

    1986-12-01

    A method was developed to incorporate the transport of several chemical components into a model of the transport of fluid mass and heat within a geothermal system. It was demonstrated that the use of coupled hydrological, thermal and chemical data allows for the determination of field porosities, amounts and regions of cool recharge into the system as well as field permeabilities and the hot reservoir volume. With the additional information a reliable prediction of the long-term cooling rate can be made.

  18. Low-Temperature Enhanced Geothermal System using Carbon Dioxide as the Heat-Transfer Fluid

    Energy Technology Data Exchange (ETDEWEB)

    Eastman, Alan D. [GreenFire Energy, Emeryville, CA (United States)

    2014-07-24

    This report describes work toward a supercritical CO2-based EGS system at the St. Johns Dome in Eastern Arizona, including a comprehensive literature search on CO2-based geothermal technologies, background seismic study, geological information, and a study of the possible use of metal oxide heat carriers to enhance the heat capacity of sCO2. It also includes cost estimates for the project, and the reasons why the project would probably not be cost effective at the proposed location.

  19. Low temperature geothermal resource evaluation of the Moses Lake-Ritzville-Connell area, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Widness, S.

    1983-11-01

    The study area is located in portions of Adams, Grant, Lincoln, and Franklin counties of eastern Washington. The area is representative of a complex stratigraphic and geohydrologic system within the basalt flows of the Columbia River Basalt Group. Fluid temperature data were collected by three different agencies. The Geological Engineering Section (WSU) at Washington State University, runs a continuous fluid temperature (FT) log as part of a complete suite of geophysical logs. The US Geological Survey (USGS) runs a continuous fluid FT log in conjunction with caliper and natural-gamma logs. Southern Methodist University (SMU) and the Washington State Department of Natural Resources, Division of Geology and Earth Resources (DNR), have cooperated in gathering FT data. The DNR-SMU data were collected by taking temperature measurements at 5 m intervals. Bottom-hole temperatures (BHT) and bottom-hole depths (BHD) of selected wells in the study area are given. A technique developed by Biggane (1982) was used to determine the geothermal gradients within the area. A least squares linear regression analysis of the relationship between the BHT and BHD was used to determine the geothermal gradient of a given well data group (WDG).

  20. Interpretation of gravity data to delineate structural features connected to low-temperature geothermal resources at Northeastern Portugal

    Science.gov (United States)

    Represas, Patricia; Monteiro Santos, F. A.; Ribeiro, José; Ribeiro, Joana A.; Almeida, Eugénio P.; Gonçalves, Rui; Moreira, Mário; Mendes-Victor, L. A.

    2013-05-01

    A great number of low-temperature geothermal fields occur in Northern-Portugal related to fractured rocks. The most important superficial manifestations of these hydrothermal systems appear in pull-apart tectonic basins and are strongly conditioned by the orientation of the main fault systems in the region. This work presents the interpretation of gravity gradient maps and 3D inversion model produced from a regional gravity survey. The horizontal gradients reveal a complex fault system. The obtained 3D model of density contrast puts into evidence the main fault zone in the region and the depth distribution of the granitic bodies. Their relationship with the hydrothermal systems supports the conceptual models elaborated from hydrochemical and isotopic water analyses. This work emphasizes the importance of the role of the gravity method and analysis to better understand the connection between hydrothermal systems and the fractured rock pattern and surrounding geology.

  1. Low Temperature Geothermal Resource Evaluation of the Moses Lake-Ritzville-Connell Area, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Widness, Scott

    1983-11-01

    The study area is located in portions of Adams, Grant, Lincoln, and Franklin counties of eastern Washington. The area is representative of a complex stratigraphic and geohydrologic system within the basalt flows of the Columbia River Basalt Group. The regional piezometric surface and stratigraphic units dip towards the southwest. Fluid temperature data were collected by three different agencies. The Geological Engineering Section (WSU) at Washington State University, runs a continuous fluid temperature (FT) log as part of a complete suite of geophysical logs. The US Geological Survey (USGS) runs a continuous fluid FT log in conjunction with caliper and natural-gamma logs. Southern Methodist University (SMU) and the Washington State Department of Natural Resources, Division of Geology and Earth Resources (DNR), have cooperated in gathering FT data. The DNR-SMU data were collected by taking temperature measurements at 5 m intervals. Bottom-hole temperatures (BHT) and bottom-hole depths (BHD) of selected wells in the study area are given in table 2. Some of the BHT data in table 2 may vary from those previously reported by WSU. These discrepancies are the result of changes in the calibration method of the FT tool. A technique developed by Giggane (1982) was used to determine the geothermal gradients within the area. A least squares linear regression analysis of the relationship between the BHT and BHD was used to determine the geothermal gradient of a given well data group (WDG). Well data groups were selected on the premises of geographic proximity, position within the regional groundwater flow system, land slope azimuth, and land slope dip. Some data points have been excluded from the linear regression analysis on the basis of factors such as duplicate logging of the same hole, down-hole flow, holes not logged to total depth, and questionable FT tool responses.

  2. Spatial distribution of temperature in the low-temperature geothermal Euganean field (NE Italy): a simulated annealing approach

    Energy Technology Data Exchange (ETDEWEB)

    Fabbri, Paolo; Trevisani, Sebastiano [Dipartimento di Geologia, Paleontologia e Geofisica, Universita degli Studi di Padova, via Giotto 1, 35127 Padova (Italy)

    2005-10-01

    The spatial distribution of groundwater temperatures in the low-temperature (60-86{sup o}C) geothermal Euganean field of northeastern Italy has been studied using a geostatistical approach. The data set consists of 186 temperatures measured in a fractured limestone reservoir, over an area of 8km{sup 2}. Investigation of the spatial continuity by means of variographic analysis revealed the presence of anisotropies that are apparently related to the particular geologic structure of the area. After inference of variogram models, a simulated annealing procedure was used to perform conditional simulations of temperature in the domain being studied. These simulations honor the data values and reproduce the spatial continuity inferred from the data. Post-processing of the simulations permits an assessment of temperature uncertainties. Maps of estimated temperatures, interquartile range, and of the probability of exceeding a prescribed 80{sup o}C threshold were also computed. The methodology described could prove useful when siting new wells in a geothermal area. (author)

  3. Low temperature geothermal energy applications in the Albuquerque area. Final report, July 1, 1978-August 18, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Kauffman, D.; Houghton, A.V.

    1979-01-01

    A study was made of the engineering and economic feasibility of hot water geothermal energy applications in the Albuquerque area. A generalized system design was developed and used as the basis for a series of economic case studies. Reservoir and user siting considerations were studied in light of the economic findings. Several specific potential applications were identified, including university campuses, industrial and commercial facilities, and residential buildings. Specific key technical problems relating to Albuquerque area applications were studied. These included environmental impacts, corrosion, scaling, heat losses in wells and transmission lines, heat exchangers, control systems, and system utilization and reliability. It is concluded that geothermal energy could be competitive with other energy sources for space heating and limited industrial use for moderate to large (10 million Btu/hr or more) energy using systems.

  4. Geothermal Energy Potential in Western United States

    Science.gov (United States)

    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)

  5. Geothermal Energy Potential in Western United States

    Science.gov (United States)

    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)

  6. Geothermal Energy: Tapping the Potential

    Science.gov (United States)

    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…

  7. A numerical analysis of a composition-adjustable Kalina cycle power plant for power generation from low-temperature geothermal sources

    OpenAIRE

    Wang, Enhua; Yu, Zhibin

    2016-01-01

    The Kalina cycle is believed to be one of the most promising technologies for power generation from low temperature heat sources such as geothermal energy. So far, most Kalina cycle power plants are designed with a working fluid mixture having a fixed composition, and thus normally operate at a fixed condensing temperature. However, the ambient temperature (i.e., heat sink) varies over a large range as the season changes over a year, particularly in continental climates. Recently, a new conce...

  8. Direct use of low temperature geothermal water by Aquafarms International, Inc. for freshwater aquaculture (prawns and associated species). An operations and maintenance manual

    Energy Technology Data Exchange (ETDEWEB)

    Broughton, R.; Price, M.; Price, V.; Grajcer, D.

    1984-04-01

    In connection with an ongoing commercial aquaculture project in the Coachella Valley, California; a twelve month prawn growout demonstration project was conducted. This project began in August, 1979 and involved the use of low temperature (85/sup 0/F) geothermal waters to raise freshwater prawns, Macrobrachium rosenbergii (deMan), in earthen ponds. The following publication is an operations and maintenance guide which may by useful for those interested in conducting similar enterprises.

  9. Heat distribution function for motion in a general potential at low temperature

    DEFF Research Database (Denmark)

    Fogedby, Hans; Imparato, Alberto

    2009-01-01

    We consider the 1D motion of an over-damped Brownian particle in a general potential in the low temperature limit. We derive an explicit expression for the probability distribution for the heat transferred to the particle. We find that the local minima in the potential yield divergent side bands...

  10. Geothermal energy market potential in industrial processing

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, R.J.; Hanny, J.A.; Knuth, W.H.

    1978-11-01

    Geothermal energy is currently being used for a number of industrial processes in countries throughout the world. Its application in the United States is mainly limited to space heating even though the temperature of the geothermal fluid is sufficient for process uses, and could be sold at attractive prices while maintaining a high return on investment. The temperature span for industrial use ranges from 40 to 275/sup 0/C, thus encompassing both the abundant low temperature and the less available high temperature resources. Hydrothermal fluids can be used either directly or indirectly dependent upon fluid quality and process needs. The barriers facing hydrothermal industrial process development are (a) the development infrastructure does not exist, (b) energy users are not aware of hydrothermal energy and its advantages, (c) federal incentives are limited, (d) resources are not fully defined.

  11. A renewable energy scenario for Aalborg Municipality based on low-temperature geothermal heat, wind power and biomass

    DEFF Research Database (Denmark)

    Østergaard, Poul Alberg; Mathiesen, Brian Vad; Möller, Bernd

    2010-01-01

    in industrial fuel use and savings and fuel-substitutions in the transport sector. With biomass resources being finite, the two marginal energy resources in Aalborg are geothermal heat and wind power. If geothermal heat is utilised more, wind power may be limited and vice versa. The system still relies...

  12. Low-temperature geothermal reservoir site evaluation in Arizona. Quarterly progress report, November 1, 1977--January 31, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Hahman, W.R. Sr.

    1978-03-01

    The Department of Energy, Division of Geothermal Energy, has charged the Bureau of Geology and Mineral Technology, Geological Survey Branch with development of a cost-effective exploration program for low- to moderate-temperature geothermal resources. As part of this program two or three demonstration projects in Arizona will be brought on stream. The site-specific exploration, evaluation and development program as well as the state wide reconnaissance exploration program is continuing. The compilation of data for the 1 : 500,000 geothermal energy resource map is continuing. Drafting and data collection for the 1 : 1,000,000 preliminary map, Geothermal Energy Resources of Arizona, Geothermal Map No. 1, requested the first week in January by DOE/DGE is nearing completion. This preliminary map should be published in March, 1978. All outside projects are either complete or on schedule.

  13. Gravity, magnetic and resistivity investigations of the Okauia Low Temperature Geothermal System in alluvial sediments of the Hauraki Depression, New Zealand

    Science.gov (United States)

    Soengkono, Supri; Reeves, Robert

    2017-04-01

    Gravity, ground magnetics, DC resistivity traversing, and time domain electromagnetic soundings (fixed-loop and in-loop) were conducted to investigate the Okauia Low Temperature Geothermal System near the eastern boundary of the Hauraki Depression in North Island of New Zealand. The gravity study revealed a hidden extension of the Tertiary-age Waiteariki Ignimbrite, underlying plio-Pleistocene alluvium deposits of the Hinuera Formation, which locally host an aquifer of warm geothermal fluids. A 3D magnetic model derived from the ground magnetic measurements helped identify probable paleo-channels within the sedimentary sequence of the Hinuera Formation. These paleo-channels could represent higher permeability at shallow (<50 m) depth, although the exact relationship between the locations of the surface thermal manifestations and identified paleo-channels is still unclear. The results of the resistivity surveys suggest that values less than 25 Ωm are indicative of the presence of warm waters at Okauia. Most warm water occurrences at Okauia take place near the Okauia Fault, particularly at 0 m RL (sea level) elevation. The near-surface extent of the Okauia Low Temperature Geothermal System can be approximated from the results of this study.

  14. Deep Groundwater Circulation within Crystalline Basement Rocks and the Role of Hydrologic Windows in the Formation of the Truth or Consequences, New Mexico Low-Temperature Geothermal System

    Science.gov (United States)

    Pepin, J.; Person, M. A.; Phillips, F. M.; Kelley, S.; Timmons, S.; Owens, L.; Witcher, J. C.; Gable, C. W.

    2014-12-01

    Hot Springs are common in amagmatic settings, but the mechanisms of heating are often obscure. We have investigated the origin of the Truth or Consequences, New Mexico low-temperature (~ 41 °C) hot springs in the southern Rio Grande rift. We tested two mechanisms that could account for the geothermal anomaly. The first scenario is that the anomaly is the result of lateral forced convection associated with a gently-dipping carbonate aquifer. The second scenario is that high permeability of crystalline basement rocks permits circulation of groundwater down to depths of 8 km prior to discharging in Truth or Consequences. To test these hypotheses, we constructed a two-dimensional hydrothermal model of the region using FEMOC. Model parameters were constrained by calibrating to measured temperatures, specific discharge rates and groundwater residence times. We collected 16 temperature profiles, 11 geochemistry samples and 6 carbon-14 samples within the study area. The geothermal waters are Na+/Cl- dominated and have apparent groundwater ages ranging from 5,500 to 11,500 years. Hot Springs geochemistry is consistent with water/rock interaction in a silicate geothermal reservoir, rather than a carbonate system. Peclet-number analysis of temperature profiles suggests specific discharge rates beneath Truth or Consequences range from 2 to 4 m/year. Geothermometry indicates maximum reservoir temperatures are around 167 °C. We were able to reasonably reproduce observed measurements using the permeable-basement scenario (10-12 m2). The carbonate-aquifer scenario failed to match observations. Our findings imply that the Truth or Consequences geothermal system formed as a result of deep groundwater circulation within permeable crystalline basement rocks. Focused geothermal discharge is the result of localized faulting, which has created a hydrologic window through a regional confining unit. In tectonically active areas, deep groundwater circulation within fractured crystalline

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1984-01-01

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

  16. Active metasomatism in the Cerro Prieto geothermal system, Baja California, Mexico: A telescoped low-pressure, low-temperature metamorphic facies series

    Science.gov (United States)

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

    1984-01-01

    In the Cerro Prieto geothermal field, carbonate-cemented, quartzofeldspathic sediments of the Colorado River delta are being actively metasomatized into calc-silicate metamorphic rocks by reaction with alkali chloride brines between 200 and 370 °C, at low fluid and lithostatic pressures and low oxygen fugacities. Our petrologic investigations of drill cores and cuttings from more than 50 wells in this field identified a prograde series of zones that include as index minerals wairakite, epidote, prehnite, and clinopyroxene. Associated divariant mineral assemblages are indicative of a very low pressure, low-temperature metamorphic facies series spanning the clay-carbonate, zeolite, greenschist, and amphibolite facies. This hydro-thermal facies series, which is now recognized in other active geothermal systems, is characterized by temperature-telescoped dehydration and decarbonation. Its equivalent can now be sought in fossil hydrothermal systems.

  17. 低温地热发电有机朗肯循环的优化%Optimization of the Low-temperature Geothermal Heat Powered Organic Ranline Cycle

    Institute of Scientific and Technical Information of China (English)

    王辉涛; 王华; 葛众; 冷婷婷

    2011-01-01

    采用(火用)分析方法及PR状态方程,建立了低温地热发电有机朗肯循环的工质优选及主要参数优化热力学方法.比较计算了以10种干流体有机工质为循环工质的低温地热发电有机朗肯循环的输出功率、(火用)效率及其余主要热力性能.结果表明,低温地热发电有机朗肯循环的性能极大地受工质的物性及蒸发温度的影响.总体来看,随着工质临界温度的升高,输出功率及(火用)效率呈下降趋势,而热效率及地热流经换热后的排放(或回灌)温度呈上升趋势.R227ea是低温地热发电有机朗肯循环较理想的工质,以其作工质的有机朗肯循环系统的输出功率及(火用)效率最高,蒸发压力及凝结压力亦处于较合适的范围.低温地热发电有机朗肯循环存在最佳蒸发温度,在最佳蒸发温度下的系统可获得最大的输出功率及(火用)效率.%The exergetic analysis method and PR equation of state were utilized to establish the thermodynamic method of working fluid selection and the optimization of the low-temperature geothermal heat powered organic Rankine cycles. Thermal performances, including power output, exergy efficiency, etc. of low-temperature geothermal heat powered organic Rankine cycles using 10 kinds of dry fluids as working fluids, were calculated and compared. The results show that: The performances of low-temperature geothermal heat powered organic Rankine cycle are greatly affected by evaporation temperature and working fluid's thermal properties. As the critical temperature of working fluid increases, the output power and exergy efficiency show a decreasing trend, but the cycle thermal efficiency and the final discharge (or rejection)temperature of the geothermal fluid show an increasing trend as a whole. Moreover, the organic Rankine cycle charged with R227ea (heptafluoropropane) gets the highest power output and exergy efficiency, and the evaporation and condensation pressures are

  18. Study and utilization of water-dominated and low-temperature geothermal fields in Italy; Itaria ni okeru nessui takuetsugata oyobi teion chinetsu shigen no kenkyu to riyo jokyo

    Energy Technology Data Exchange (ETDEWEB)

    Yasukawa, K. [Geological Survey of Japan, Tsukuba (Japan)

    1998-06-15

    This paper reports the state of research and development of hot-water dominated and low-temperature geothermal resources in Italy. Geothermal explorations and studies are conducted by the Italian electric power company ENEL and the International Geothermal Research Institute, of which the development of geothermal power generation is carried out by ENEL. Hot water dominated geothermal fields in the central Italy include the Tuscany area having Larderello south of Firenze and the Monte Amiata area, the Latium area around Rome, and the Campania area around Napoli. Low-temperature geothermal fields in the northern Italy include Ferrara, Vicenza, Euganei Hills, and Aqui Terme. A large number of wells have been drilled to as deep as 3000 m in high-temperature geothermal areas for power generation. The present drilling is targeted exclusively at deep reservoirs. In the hot water dominated areas in the central Italy, power plants of 20-MW class are built even in areas with not too high productivity, where waste hot water is utilized in binary cycle. In the northern low-temperature geothermal area, warm water is utilized directly. 8 refs., 14 figs.

  19. Comparative analysis of CO2-based transcritical Rankine cycle and HFC245fa-based subcritical organic Rankine cycle using low-temperature geothermal source

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A detailed thermodynamic and techno-economic comparison is presented for a CO2-based transcritical Rankine cycle and a subcritical organic Rankine cycle (ORC) using HFC245fa (1,1,1,3,3-pentafluoro-propane) as the working fluid driven by the low-temperature geothermal source,in order to determine the configuration that presents the maximum net power output with a minimum investment.The evaluations of both Rankine cycles have been performed based on equal thermodynamic mean heat rejection temperature by varying certain system operating parameters to achieve each Rankine cycle’s optimum design at various geothermal source temperature levels ranging from 80oC to 120oC.The results obtained show that the optimum ther-modynamic mean heat injection temperatures of both Rankine cycles are distributed in the scope of 55% to 65% of a given geothermal source temperature level,and that the CO2-based transcritical Rankine cycle presents 3% to 7% higher net power output,84% reduction of turbine inlet volume flow rate,47% reduction of expansion ratio and 1.68 times higher total heat transfer capacity compared with the HFC245fa-based subcritical ORC.It is also indicated that using the CO2-based transcritical system can reduce the dimension of turbine design.However,it requires larger heat transfer areas with higher strength heat exchanger materials because of the higher system pressure.

  20. Low-Temperature Biodiesel Research Reveals Potential Key to Successful Blend Performance (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2012-02-01

    Relatively low-cost solutions could improve reliability while making biodiesel blends an affordable option. While biodiesel has very low production costs and the potential to displace up to 10% of petroleum diesel, until now, issues with cold weather performance have prevented biodiesel blends from being widely adopted. Some biodiesel blends have exhibited unexplained low-temperature performance problems even at blend levels as low as 2% by volume. The most common low-temperature performance issue is vehicle stalling caused by fuel filter clogging, which prevents fuel from reaching the engine. Research at the National Renewable Energy Laboratory (NREL) reveals the properties responsible for these problems, clearing a path for the development of solutions and expanded use of energy-conserving and low-emissions alternative fuel. NREL researchers set out to study the unpredictable nature of biodiesel crystallization, the condition that impedes the flow of fuel in cold weather. Their research revealed for the first time that saturated monoglyceride impurities common to the biodiesel manufacturing process create crystals that can cause fuel filter clogging and other problems when cooling at slow rates. Biodiesel low-temperature operational problems are commonly referred to as 'precipitates above the cloud point (CP).' NREL's Advanced Biofuels team spiked distilled soy and animal fat-derived B100, as well as B20, B10, and B5 biodiesel blends with three saturated monoglycerides (SMGs) at concentration levels comparable to those of real-world fuels. Above a threshold or eutectic concentration, the SMGs (monomyristin, monopalmitin, and monostearin) were shown to significantly raise the biodiesel CP, and had an even greater impact on the final melting temperature. Researchers discovered that upon cooling, monoglyceride initially precipitates as a metastable crystal, but it transforms over time or upon slight heating into a more stable crystal with a much lower

  1. Geothermal heat. Potential, danger, efficiency; Erdwaerme. Potential, Gefahr, Nutzen

    Energy Technology Data Exchange (ETDEWEB)

    Reichel, Wolfgang [Ingenieurbuero Timmer Reichel GmbH, Haan (Germany)

    2010-07-01

    The author of the contribution under consideration reports on the potential, danger and utilization of geothermal heat. Geothermal heat promises the solution of numerous energy problems. From the use of near-surface layers which substantially are affected by enviromental impacts such as solar radiation up to the depth use of the heat flow from the interior of the earth, there exist very different energy sources which are to be considered separately for each application.

  2. A CO2-Silica Geothermometer for Low Temperature Geothermal Resource Assessment, with Application to Resources in the Safford Basin, Arizona

    Energy Technology Data Exchange (ETDEWEB)

    Witcher, James C.; Stone, Claudia

    1983-11-01

    Geothermics is the study of the earth's heat energy, it's affect on subsurface temperature distribution, it's physical and chemical sources, and it's role in dynamic geologic processes. The term, geothermometry, is applied to the determination of equilibrium temperatures of natural chemical systems, including rock, mineral, and liquid phases. An assemblage of minerals or a chemical system whose phase composition is a function of temperature and pressure can be used as a geothermometer. Thus a geothermometer is useful to determine the formation temperature of rock or the last equilibrium temperature of a flowing aqueous solution such as ground water and hydrothermal fluids.

  3. Summary of the 2010 assessment on medium- to low-temperature geothermal resources in Mexico; Resumen de la evaluacion 2010 de los recursos geotermicos mexicanos de temperatura intermedia a baja

    Energy Technology Data Exchange (ETDEWEB)

    Iglesias, Eduardo R.; Torres, Rodolfo J.; Martinez Estrella, J. Ignacio; Reyes Picasso, Neftali [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: iglesias@iie.org.mx

    2011-07-15

    In 2003 we published our first assessment of the medium- to low-temperature (T {<=} 200 degrees Celsius) Mexican geothermal resources. The assessment was based on a database of 1,358 geothermal manifestations (surface manifestations, e.g. springs, fumaroles, water wells, etc.) identified at that time. Due to a lack of information on one or more relevant parameters, such as geographical coordinates, reservoir or surface temperatures, types of fluid, etc., that assessment included only about 30% of the geothermal manifestations in the database. Since then our group has increased significantly the amount of information in the database, using field work and data compilation from different sources. We have developed a database linked with a Geographical Information System (GIS). This work presents an updated assessment of the medium- to low-temperature Mexican geothermal resources based on our current database, which includes 2,361 geothermal manifestations. As before, we have relied on the volume method and Montecarlo simulations to estimate geothermal resources and their uncertainties for each identified geothermal system. These geothermal systems very often include more than one geothermal manifestation, generally increasing the reliability of the individual estimations. In all, we estimated the geothermal resources of 918 individual geothermal systems which included 1,797 geothermal manifestations (as before, a significant fraction of the identified manifestations lack relevant information) located in 26 of the 32 Mexican States. In most cases these resources would be classified as inferred resources, according to the Australian Geothermal Code. We then added the inferred thermal-energy statistical distributions of the 918 geothermal systems by Montecarlo simulation, obtaining the total estimated geothermal resources of the 26 Mexican States and its uncertainty. With the resulting statistical distribution, we estimated the total-thermal energy stored in the 918

  4. Sperry Low Temperature Geothermal Conversion System, Phase I and Phase II. Volume IV. Field activities. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, C.

    1984-01-01

    This volume describes those activities which took place at the Sperry DOE Gravity Head plant site at the East Mesa Geothermal Reservoir near Holtville, California between February 1980, when site preparation was begun, and November 1982, when production well 87-6 was permanently abandoned. Construction activities were terminated in July 1981 following the liner collapse in well 87-6. Large amounts of program time manpower, materials, and funds had been diverted in a nine-month struggle to salvage the production well. Once these efforts proved futile, there was no rationale for continuing with the site work unless and until sufficient funding to duplicate well 87-6 was obtained. Activities reported here include: plant construction and pre-operational calibration and testing, drilling and completion of well 87-6, final repair effort on well 87-6, abandonment of well 87-6, and performance evaluation of well 87.6. (MHR)

  5. Geothermal Energy: Delivering on the Global Potential

    Directory of Open Access Journals (Sweden)

    Paul L. Younger

    2015-10-01

    Full Text Available Geothermal energy has been harnessed for recreational uses for millennia, but only for electricity generation for a little over a century. Although geothermal is unique amongst renewables for its baseload and renewable heat provision capabilities, uptake continues to lag far behind that of solar and wind. This is mainly attributable to (i uncertainties over resource availability in poorly-explored reservoirs and (ii the concentration of full-lifetime costs into early-stage capital expenditure (capex. Recent advances in reservoir characterization techniques are beginning to narrow the bounds of exploration uncertainty, both by improving estimates of reservoir geometry and properties, and by providing pre-drilling estimates of temperature at depth. Advances in drilling technologies and management have potential to significantly lower initial capex, while operating expenditure is being further reduced by more effective reservoir management—supported by robust models—and increasingly efficient energy conversion systems (flash, binary and combined-heat-and-power. Advances in characterization and modelling are also improving management of shallow low-enthalpy resources that can only be exploited using heat-pump technology. Taken together with increased public appreciation of the benefits of geothermal, the technology is finally ready to take its place as a mainstream renewable technology, exploited far beyond its traditional confines in the world’s volcanic regions.

  6. Characterizing U.S. Heat Demand Market for Potential Application of Geothermal Direct Use

    Energy Technology Data Exchange (ETDEWEB)

    McCabe, Kevin; Gleason, Michael; Reber, Tim; Young, Katherine R.

    2017-05-01

    In this paper, we assess the U.S. demand for low-temperature thermal energy at the county resolution for four major end-use sectors: residential buildings, commercial buildings, manufacturing facilities, and agricultural facilities. Existing, publicly available data on the U.S. thermal demand market are characterized by coarse spatial resolution, with assessments typically at the state-level or larger. For many uses, these data are sufficient; however, our research was motivated by an interest in assessing the potential demand for direct use (DU) of low-temperature (30 degrees to 150 degrees C) geothermal heat. The availability and quality of geothermal resources for DU applications are highly spatially heterogeneous; therefore, to assess the potential market for these resources, it is necessary to understand the spatial variation in demand for low-temperature resources at a local resolution. This paper presents the datasets and methods we used to develop county-level estimates of the thermal demand for the residential, commercial, manufacturing, and agricultural sectors. Although this analysis was motivated by an interest in geothermal energy deployment, the results are likely to have broader applications throughout the energy industry. The county-resolution thermal demand data developed in this study for four major U.S. sectors may have far-reaching implications for building technologies, industrial processes, and various distributed renewable energy thermal resources (e.g. biomass, solar).

  7. Geothermics of Nile delta and southeast Mediterranean: Investigation and geothermal energy potential

    Energy Technology Data Exchange (ETDEWEB)

    Zein El-Din, M.Y.; Zaghloul, Z.M.; Khidr, I.H. (Al Azhar Univ., Cairo (Egypt))

    1988-08-01

    The authors collected 289 temperature readings from 66 exploratory wells randomly distributed in an area about 57,000 km{sup 2} from different rock units of Tertiary and Quaternary ages. The bottom-hole temperature (BHT) readings were corrected using an empirical equation based on actual static formation temperatures collected from the study area. The authors modified the Fertl and Wichmann method to apply to the study area. If the Fertl and Wichmann curve is applied, readings can be corrected using a deduced relation. The geothermal gradient for each well calculated used the best-fit method utilizing all recorded BHTs in that well. A new geothermal gradient map was constructed using the corrected BHT values. A genetic relationship between the geothermal gradient and lithology, tectonic setup, gas saturation, and water saturation of the subsurface formations in the Nile delta and southeast Mediterranean area was sought. Isothermal maps at different depths in the study area were constructed. Areas of relatively high subsurface temperature were delineated. The Abu Madi gas field as a case study for geothermal behavior was emphasized. The geothermal reservoirs in the study area as possible new and renewable energy resources were defined and classified as low-temperature reservoirs. Two geothermal reservoirs have been recorded: a shallow one associated with Mit Ghamr-El Wastani rock units and a deep one associated with abu Madi-Qawassim Formations.

  8. Shallow geothermal potential of Cantone Ticino through map modeling

    Science.gov (United States)

    Perego, Rodolfo; Pera, Sebastian; Belliardi, Marco

    2017-04-01

    Low enthalpy geothermal energy is continuously growing in importance within Europe, since it is a reliable and efficient renewable energy, especially when exploited by closed-loop systems. Switzerland hosts one of the greatest density of low temperature geothermal systems in the world. Cantone Ticino includes more than 4000 probes, with an overall installed length of more than 500 km and the requests are continuously growing: the management of this technology must be therefore accurately faced both from a physical and political standpoint. The current authorization approach for closed-loop systems in Cantone Ticino, however, is mainly based on basic maps taking into account the presence of restrictions arising from the enforcement of the water protection act and ordinance. Closed-loop systems cannot be installed within S groundwater protection zones, and within the Au (usable groundwater) sector the installation of such systems is allowed in specific areas where the presence of conflicts precludes groundwater exploitation for drinking purposes. The described procedure, however, does not consider the subsurface potential nor the techno-economic constraints. More empirically based maps could instead give precious planning indications and they could also be useful, if properly verified, to perform pre-emptive estimates of technical and economic parameters. The procedure for the mapping of the geothermal potential started with the identification of the main parameters affecting it, such as the ground surface temperature (GST), thermal conductivity of both outcrops/unconsolidated material and heat flux/geothermal gradient. Maps for all of these parameters were created and some of them were compared with real measurement data, with satisfactory results. The estimated error for the ground temperature reconstruction was quantified in ±1°C, while the error of the hydraulic conductivity reconstruction was estimated as half of an order of magnitude. A reference set of

  9. Geothermal Power Potential in the Tatun Volcano Group, Taiwan

    Science.gov (United States)

    Tseng, H. H.; Song, S.

    2013-12-01

    Recent energy issues have concentrated the attention on finding alternative ones. National demands for renewable and sustainable energy increase rapidly, especially the geothermal power production, which is viewed as the most potential opportunity. This study attempts to estimate the geothermal powers in the Tatung Volcano Group (TVG), Taiwan and evaluate the possibility to develop the Enhanced Geothermal System. Tatung Volcano Group is located at the northwest part of Taiwan. It has violent volcanism during 0.8-0.20Ma, and is still active with many thermal manifestations. The young volcanic activity provides the TVG with high geothermal gradient and is well suitable for exploiting geothermal resources. Many explorations on geothermal energy have been accomplished in this area during1966-1973. They included resistivity survey, magnetic prospecting, gravity method, seismic prospecting and etc. In this study, we base on previous data and apply the probabilistic volumetric method proposed by Geotherm EX Inc., modified from the approach introduced by the USGS to evaluate the geothermal power potential in TVG. Meanwhile, use a Monte Carlo simulation technique to calculate the probability distribution of potentially recoverable energy reserves. The results show that the mean value is 270Mw, and P50 is 254Mw for 30 years, separately. Furthermore, the power potential of enhanced geothermal system in TVG is also estimated by the quantitative model proposed by Massachusetts Institute of Technology (MIT 2006). The results suggest that the mean value is 3,000 MW and P50 is 2,780 MW for 30 years, separately.

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

    Energy Technology Data Exchange (ETDEWEB)

    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. Trichoderma spp.capable of growing at low temperatures with biocontrol potential

    Institute of Scientific and Technical Information of China (English)

    Szakacs G; Tavaszi A

    2004-01-01

    @@ Though there are successful commercial biocontrol products with Trichoderma spp. In many countries including US, Israel and Europe, their usefulness is limited in cold environments such as mid-and northern part of Europe, US and Canada, especially in the late fall, winter and early spring period.Trichoderma isolates capable of growing at low temperatures (5-10 ℃) and showing good antagonistic properties against plant pathogenic fungi may have therefore both scientific and commercial value.

  12. Volcanostratigraphic Approach for Evaluation of Geothermal Potential in Galunggung Volcano

    Science.gov (United States)

    Ramadhan, Q. S.; Sianipar, J. Y.; Pratopo, A. K.

    2016-09-01

    he geothermal systems in Indonesia are primarily associated with volcanoes. There are over 100 volcanoes located on Sumatra, Java, and in the eastern part of Indonesia. Volcanostratigraphy is one of the methods that is used in the early stage for the exploration of volcanic geothermal system to identify the characteristics of the volcano. The stratigraphy of Galunggung Volcano is identified based on 1:100.000 scale topographic map of Tasikmalaya sheet, 1:50.000 scale topographic map and also geological map. The schematic flowchart for evaluation of geothermal exploration is used to interpret and evaluate geothermal potential in volcanic regions. Volcanostratigraphy study has been done on Galunggung Volcano and Talaga Bodas Volcano, West Java, Indonesia. Based on the interpretation of topographic map and analysis of the dimension, rock composition, age and stress regime, we conclude that both Galunggung Volcano and Talaga Bodas Volcano have a geothermal resource potential that deserve further investigation.

  13. The Geothermal Potential, Current and Opportunity in Taiwan

    Science.gov (United States)

    Song, Sheng-Rong

    2016-04-01

    Located in the west Pacific Rim of Fire, Taiwan possesses rich geothermal resources due to volcanic activities and rapid uplifting of plate collision. Based on available data prior to 1980, Taiwan may have about 1 GWe of potential shallow geothermal energy, which is less than 3% of the national gross power generation. A 3-Mw pilot power plant, therefore, was constructed in 1981 and terminated in 1993 in the Chingshui geothermal field of Ilan, northeastern Taiwan. Recently, one of the National Science & Technology Program (NSTP) projects has been conducting research and reevaluating the island-wide deep geothermal energy. Four hot potential sites have been recognized. They are: (1) Tatun Volcano Group of northern Taiwan; (2) I-Lan Plain of NE Taiwan; (3) Lu-Shan area of Central Taiwan; and (4) Hua-Tung area of eastern Taiwan. We found that the geothermal resource in Taiwan may be as high as 160 GWe, with 33.6 GWe of exploitable geothermal energy. There are no any commercial geothermal power plants until now in Taiwan, although the potential is great. However, geothermal energy has been listed as one of major tasks of National Energy Program, Phase II (NEP-II) in Taiwan. We will conduct more detailed geothermal energy surveys on some proposed hot sites and to construct an EGS pilot geothermal plant with 1 MWe capability in a few years. Currently, there are three nuclear power plants, named No. 1, 2 & 3, in operations, which produce 16.5% gross generation of electricity and one (No. 4) is under construction, but is stopped and sealed now in Taiwan. Furthermore, the life-span of 40-year operation for those three power plants will be close-at hand and retire in 2018-2019, 2021-2023 and 2024-2025, respectively. Therefore, to find alternative energy sources, especially on the clean, renewable and sustainable ones for generating electricity are emergent and important for Taiwan's government in next few years. Among various energy sources, geothermal energy can be as base

  14. The potential to supply low temperature district heating to existing building area

    DEFF Research Database (Denmark)

    Li, Hongwei; Svendsen, Svend

    2013-01-01

    Low-temperature district heating (LTDH) has the advantages as reduced network heat loss, improved quality match between energy supply and energy demand, and increased utilization of low-grade waste heat and renewable energy. The LTDH represents the next generation district heating (DH) system....... The use of LTDH for low energy buildings was demonstrated through pilot projects carried out in Denmark. However, the majority of the buildings were built during the time when there had little requirement for building energy conservation. In order to implement the LTDH in a large scale, its feasibility...

  15. Assessment of the geothermal energy potential of the 'Canton de Vaud', Switzerland; Evaluation du potentiel geothermique du canton de Vaud

    Energy Technology Data Exchange (ETDEWEB)

    Wilhelm, J. [Jules Wilhelm, Pully (Switzerland); Bianchetti, G. [ALPGEO, Sierre (Switzerland); Vuataz, F.-D. [University of Neuchatel, Neuchatel (Switzerland)

    2003-07-01

    This report presents an assessment of the geothermal energy potential in the provincial state of Vaud in western Switzerland. According to the authors the prospect for the three current main technologies: low-temperature surface water, deep hot water springs and advanced geothermal systems, is good. In about 10 years it would be possible to extract some 3.6x10{sup 6} MJ per year from low-temperature surface water while the energy production from deep hot springs could be near to 2x10{sup 4} MJ. Finally, in the forthcoming 20 years the construction of 3 advanced geothermal power plants ('Deep Heat Mining', i.e. the extraction of deep-rock thermal energy by water circulation) could produce about 30 MW electricity in a cogeneration operation mode. Recommendations are given regarding measures needed at the political level to promote geothermal power plants.

  16. Chlorella mirabilis as a potential species for biomass production in low temperature environment

    Directory of Open Access Journals (Sweden)

    Satya Prakash Shukla

    2013-04-01

    Full Text Available Successful adaptation/acclimatization to low temperatures in micro-algae is usually connected with production of specific biotechnologically important compounds. In this study, we evaluated the growth characteristics in a micro-scale mass cultivation of the Antarctic soil green alga Chlorella mirabilis under different nitrogen and carbon sources followed by analyses of fatty acid contents. The micro-scale mass cultivation was performed in stable (in-door and variable (out-door conditions during winter and/or early spring in the Czech Republic. In the in-door cultivation, the treatments for nitrogen and carbon sources determination included pure Z medium (control, Z, Z medium + 5% glycerol (ZG, Z medium + 5% glycerol + 50 µM KNO3 (ZGN, Z medium + 5% glycerol + 200µM NH4Cl (ZGA, Z medium + 5% glycerol + 1 mM Na2CO3 (ZNC, Z medium + 5% glycerol + 1 mM Na2CO3 + 200µM NH4Cl (ZGCA and Z medium + 5% glycerol + 1 mM Na2CO3 + 50 µM KNO3 (ZGCN and were performed at 15°C with an irradiance of 75 µmol m-2 s-1. During the out-door experiments, the night-day temperature ranged from -6.6°C to 17.5°C (daily average 3.1±5.3 °C and irradiance ranged from 0 to 2300 µmol m-2 s-1 (daily average 1500±1090 µmol m-2 s-1. Only the Z, ZG, ZGN and ZGC treatments were used in the out-door cultivation. In the in-door mass cultivation, all nitrogen and carbon sources additions increased the growth rate with the exception of ZGA. When individual sources were considered, only the effect of 5% glycerol addition was significant. On the other hand, the growth rate decreased in the ZG and ZGN treatments in the out-door experiment, probably due to carbon limitation. Fatty acid composition showed increased production of linoleic acid in the glycerol treatments. The studied strain of C. mirabilis is proposed to be a promising source of linoleic acid in low temperature mass cultivation biotechnology. This strain is a perspective model organism for biotechnology in low-temperature

  17. Low temperature photoluminescence of a nanostructured silicon-based semiconductor for potential applications

    Science.gov (United States)

    Raddenzati, A.; Hosatte, M.; Basta, M.; Kuznicki, Z. T.; Remouche, M.; Meyrueis, P.; Haeberlé, O.

    2016-05-01

    A nanoscale layer of amorphized silicon is obtained by implantations with silicon ions through a P-doped FZ-silicon wafer material few nanometers below the wafer surface. After a controlled annealing, the amorphized silicon material is sandwiched between two layers of recrystallized silicon. Defects remain at the interface c-Si/a-Si/c-Si. Photoluminescence at very low temperature is experimented to determine the energy levels generated by this design. TEM pictures show that some nanocrystalline elements are located close to the interface surrounded by a-Si. However, the photoluminescence spectra do not present any signal of luminescence from them. This could be due to random sizes of nanocrystals. Then, a scan from energies below the silicon bandgap has been realized at 8 K. The spectrum is composed of multiple narrow peaks close to the conduction band and a broadband from 0.78 eV to 1.05 eV. In order to determine the origin of these signals, spectra of three distinct peaks were collected at different temperatures from 8 K to 120 K. The broadband collapses more rapidly by increasing the temperature than the narrow lines and theirs maxima of intensity differ.

  18. Reference book on geothermal direct use

    Energy Technology Data Exchange (ETDEWEB)

    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.

  19. Combined Geothermal Potential of Subsurface Urban Heat Islands

    Science.gov (United States)

    Benz, Susanne; Bayer, Peter; Menberg, Kathrin; Blum, Philipp

    2016-04-01

    The subsurface urban heat island (SUHI) can be seen as a geothermal potential in form of elevated groundwater temperatures caused by anthropogenic heat fluxes into the subsurface. In this study, these fluxes are quantified for an annual timeframe in two German cities, Karlsruhe and Cologne. Our two-dimensional (2D) statistical analytical model determines the renewable and sustainable geothermal potential caused by six vertical anthropogenic heat fluxes into the subsurface: from (1) elevated ground surface temperatures, (2) basements, (3) sewage systems, (4) sewage leakage, (5) subway tunnels, and (6) district heating networks. The results show that at present 2.15 ± 1.42 PJ and 0.99 ± 0.32 PJ of heat are annually transported into the shallow groundwater of Karlsruhe and Cologne, respectively, due to anthropogenic heat fluxes into the subsurface. This is sufficient to sustainably cover 32% and 9% of the annual residential space heating demand of Karlsruhe and Cologne, respectively. However, most of the discussed anthropogenic fluxes into the subsurface are conductive heat fluxes and therefore dependent on the groundwater temperature itself. Accordingly, a decrease in groundwater temperature back to its natural (rural) state, achieved through the use of geothermal heat pumps, will increase these fluxes and with them the sustainable potential. Hence, we propose the introduction of a combined geothermal potential that maximizes the sustainability of urban shallow geothermal energy use and the efficiency of shallow geothermal systems by balancing groundwater temperature with anthropogenic heat fluxes into the subsurface. This will be a key element in the development of a demand-oriented, cost-efficient geothermal management tool with an additional focus on the sustainability of the urban heat sources.

  20. Potential benefits of geothermal electrical production from hydrothermal resources

    Energy Technology Data Exchange (ETDEWEB)

    Bloomster, C.H.; Engel, R.L.

    1976-06-01

    The potential national benefits of geothermal electric energy development from the hydrothermal resources in the West are estimated for several different scenarios. The U.S. electrical economy is simulated by computer using a linear programming optimization technique. Under most of the scenarios, benefits are estimated at $2 to $4 billion over the next 50 years on a discounted present value basis. The electricity production from hydrothermal plants reaches 2 to 4 percent of the national total, which will represent 10 to 20 percent of the installed capacity in the West. Installed geothermal capacity in 1990 is estimated to be 9,000 to 17,000 Mw(e). The geothermal capacity should reach 28,000 to 65,000 Mw(e) by year 2015. The ''most likely'' scenario yields the lower values in the above ranges. Under this scenario geothermal development would save the utility industry $11 billion in capital costs (undiscounted); 32 million separative work units; 64,000 tons of U/sub 3/O/sub 8/; and 700 million barrels of oil. The most favorable scenario for geothermal energy occurs when fossil fuel prices are projected to increase at 5 percent/year. The benefits of geothermal energy then exceed $8 billion on a discounted present value basis. Supply curves were developed for hydrothermal resources based on the recent U.S. Geological Survey (USGS) resource assessment, resource characteristics, and projected power conversion technology and costs. Geothermal plants were selected by the optimizing technique to fill a need for ''light load'' plants. This infers that geothermal plants may be used in the future primarily for load-following purposes.

  1. Estimation of the sustainable geothermal potential of Vienna

    Science.gov (United States)

    Tissen, Carolin; Benz, Susanne A.; Keck, Christiane A.; Bayer, Peter; Blum, Philipp

    2017-04-01

    Regarding the limited availability of fossil fuels and the absolute necessity to reduce CO2 emissions in order to mitigate the worldwide climate change, renewable resources and new energy systems are required to provide sustainable energy for the future. Shallow geothermal energy holds a huge untapped potential especially for heating and hot water, which represent up to 50% of the global energy demand. Previous studies quantified the capacity of shallow geothermal energy for closed and open systems in cities such as Vienna, London (Westminster) and Ludwigsburg in Germany. In the present study, these approaches are combined and also include the anthropogenic heat input by the urban heat island (UHI) effect. The objective of the present study is therefore to estimate the sustainable geothermal potential of Vienna. Furthermore, the amount of energy demand for heating and hot water that can be supplied by open and closed geothermal systems will be determined. The UHI effect in Vienna is reflected in higher ground water temperatures within the city centre (14 ˚ C to 18 ˚ C) in comparison to lower ones in rural areas (10 ˚ C to 13 ˚ C). A preliminary estimation of the anthropogenic heat flow into the ground water caused by elevated basement temperatures and land surface temperatures is 3,5 × 108 kWh/a. This additional heat flow leads to a total geothermal potential which is 2.5 times larger than the estimated annual energy demand for heating and hot water in Vienna.

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

    Science.gov (United States)

    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.

  3. Is radon a potential risk in geothermal fields?

    Energy Technology Data Exchange (ETDEWEB)

    Balcazar, M.; Tavera, L.; Lopez, A. [Instituto Nacional de Investigaciones Nucleares, Mexico City (Mexico)

    1998-12-31

    Some environmental groups in Mexico have shown concern, by the fact that natural radon emanation in geothermal fields could be considered as a potential risk for human health. As part of the studies recommended by the Ministry of Energy and to provide technical answers to the request of environmental groups, a study of the radon emanation and its impact to human health was carried out at the Primavera Mexican geothermal energy field under prospecting. It was found that radon concentration decreases with temperature of geothermal fluids and increases with the enthalpy of the well. In any case, using the appropriate corrections, radon values were similar to those of ground water. Radon values in the atmosphere of the field show no potential risk for human health. (author)

  4. Geothermal Energy.

    Science.gov (United States)

    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)

  5. ThermoGIS - Unlocking the Geothermal potential of the Netherlands

    NARCIS (Netherlands)

    Pluymaekers, M.P.D.; Wees, J.D. van

    2014-01-01

    A resource and performance assessment methodology has been developed to designate prospective high permeable clastic aquifers and to assess the amount of potential geothermal energy in the Netherlands. It builds from the wealth of deep subsurface data from oil and gas exploration and production whic

  6. ThermoGIS - Unlocking the Geothermal potential of the Netherlands

    NARCIS (Netherlands)

    Pluymaekers, M.P.D.; Wees, J.D. van

    2014-01-01

    A resource and performance assessment methodology has been developed to designate prospective high permeable clastic aquifers and to assess the amount of potential geothermal energy in the Netherlands. It builds from the wealth of deep subsurface data from oil and gas exploration and production whic

  7. ThermoGIS - Unlocking the Geothermal potential of the Netherlands

    NARCIS (Netherlands)

    Pluymaekers, M.P.D.; Wees, J.D. van

    2014-01-01

    A resource and performance assessment methodology has been developed to designate prospective high permeable clastic aquifers and to assess the amount of potential geothermal energy in the Netherlands. It builds from the wealth of deep subsurface data from oil and gas exploration and production

  8. Auxiliary Heating of Geothermally Preheated Water or CO2 - A Potential Solution for Low- to Moderate-Temperature Geothermal Resources

    Science.gov (United States)

    Kong, X.; Garapati, N.; Adams, B. M.; Randolph, J.; Kuehn, T. H.; Saar, M. O.

    2015-12-01

    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 compare over a range of parameters the net power and efficiencies of hybrid geothermal power plants that use brine or CO2 as the subsurface working fluid, that are then heated further with a secondary energy source that is unspecified here. Parameters varied include the subsurface working fluid (brine vs. CO2), geothermal reservoir depth (2.5-4.5 km), and turbine inlet temperature (200-600°C) after auxiliary heating. The hybrid power plant is numerically modeled using an iterative coupling approach of TOUGH2-ECO2N/ECO2H (Pruess, 2004) for simulation of the subsurface reservoir and Engineering Equation Solver for well bore fluid flow and surface power plant performance. We find that hybrid power plants that are CO2-based (subsurface) systems have higher thermal efficiencies than the brine based systems at low turbine inlet temperatures. Specifically, our results indicate that geothermal hybrid plants that are CO2-based are more efficient than brine-based systems when the contribution of the geothermal resource energy is higher than 48%.

  9. Preparation of Ultrahigh Potential Gradient of ZnO Varistors by Rare-Earth Doping and Low-Temperature Sintering

    Directory of Open Access Journals (Sweden)

    Lei Ke

    2013-01-01

    Full Text Available The effects of rare-earth doping and low-temperature sintering on electrical properties of ZnO varistors were investigated. The potential gradient (E1mA of the ZnO varistors increased significantly to 2247.2 V/mm after doping 0.08 mol% of Y2O3 and sintering at 800°C for 2 h. The notable decrease of the grain size with the given experimental conditions was the origin for the increase in E1mA. During the process of high-temperature sintering, both the oxygen at the grain boundary interface and the neutralisation of the ions on the depletion layer were directly reduced, which caused the weight loss and the internal derangement of double Schottky barriers.

  10. Potential effects of environmental regulatory procedures on geothermal development

    Energy Technology Data Exchange (ETDEWEB)

    Beeland, G.V.; Boies, D.B.

    1981-01-01

    The potential effects of several types of applicable environmental regulatory procedures on geothermal development were assessed, and particular problem areas were identified. The possible impact of procedures adopted pursuant to the following Federal statutes were analyzed: Clean Air Act; Clean Water Act; Safe Drinking Water Act; and Resource Conservation and Recovery Act. State regulations applicable, or potentially applicable, to geothermal facilities were also reviewed to determine: permit information requirements; pre-permit air or water quality monitoring requirements; effect of mandated time frames for permit approval; and potential for exemption of small facilities. The regulations of the following states were covered in the review: Alaska; Arizona; California; Colorado; Hawaii; Idaho; Montana; Nevada; New Mexico; Oregon; Utah; Washington; and Wyoming. (MHR)

  11. Geothermal potential of Ascension Island, south Atlantic. Phase I. Preliminary examination

    Energy Technology Data Exchange (ETDEWEB)

    Sibbett, B.S.; Neilson, D.L.; Ramsthaler, J.H.; Shane, M.K.

    1982-09-01

    A preliminary evaluation of the potential for an economic geothermal resource at Ascension Island was completed. It is concluded that there is a high potential for the presence of a geothermal resource under the Island. A conceptual plant has been designed assuming the resource potential located near Gannet Hill is developed. A 7% discounted payback of 5.9 years was calculated for the baseline geothermal plant. Geothermal development can be easily integrated into the Ascension Island power system in that a selection of small, portable, skid mounted, turn key power geothermal generating systems are commercially available. Geologic findings and plant analysis are summarized.

  12. Geothermal potential in Mexico; Potencial geotermico de la republica mexicana

    Energy Technology Data Exchange (ETDEWEB)

    Ordaz Mendez, Christian Arturo; Flores Armenta, Magaly; Ramirez Silva, German [Comision Federal de Electricidad, Gerencia de Proyectos Geotermoelectricos, Morelia, Michoacan (Mexico)]. E-mail: christian.ordaz@cfe.gob.mx

    2011-01-15

    Globally, Mexico is the fourth largest generator of geothermal electricity with an installed capacity of 958 MWe. The Gerencia de Proyectos Geotermoelectricos (GPG, Geothermal-electric division of the Federal Commision for Electricity -CFE) is responsible for using geothermal resources. The GPG calculated the country's geothermal potential as part of CFE's strategy to increase power generation through non-conventional sources. The calculation departed from the GPG's national inventory of thermal manifestations, which is composed of 1380 manifestations scattered throughout the country. At each, surface temperatures were measured and subsurface temperatures estimated by geo-thermometers. The calculation of the geothermal potential was based on the classifying these manifestations by geo-thermometric temperature ranges, providing for high, medium and low enthalpy resources. The volumetric method was used to obtain the national geothermal potential. The results indicate that the Potential Reserves of high-enthalpy resources amounts to 5691 MWe; of moderate-enthalpy resources, 881 MWe; and of low-enthalpy resources, 849 MWe -a total of 7422 MWe. Moreover, the Probable Reserves for high-enthalpy resources amounts to 1643 MWe; of moderate-enthalpy resources, 220 MWe; and of low-enthalpy resources, 212 MWe -a total of 2077 MWe. Finally the Proved Reserves were considered, defined as the additional capacity able to be installed in each known geothermal field, for a total of 186 MWe. All the information was processed and integrated using the Geographic Information System (GIS) ArcGis 9.2 (copyright), resulting in the CFE's intranet publication of the Geothermal Potential Map of Mexico. [Spanish] A nivel mundial, Mexico ocupa el cuarto lugar como generador de electricidad por medio de la energia geotermica con una capacidad instalada de 958 MWe. La Gerencia de Proyectos Geotermoelectricos (GPG) es la responsable del aprovechamiento de estos recursos y como

  13. Spatial data analysis and integration for regional-scale geothermal potential mapping, West Java, Indonesia

    Energy Technology Data Exchange (ETDEWEB)

    Carranza, Emmanuel John M.; Barritt, Sally D. [Department of Earth Systems Analysis, International Institute for Geo-information Science and Earth Observation (ITC), Enschede (Netherlands); Wibowo, Hendro; Sumintadireja, Prihadi [Laboratory of Volcanology and Geothermal, Geology Department, Institute of Technology Bandung (ITB), Bandung (Indonesia)

    2008-06-15

    Conceptual modeling and predictive mapping of potential for geothermal resources at the regional-scale in West Java are supported by analysis of the spatial distribution of geothermal prospects and thermal springs, and their spatial associations with geologic features derived from publicly available regional-scale spatial data sets. Fry analysis shows that geothermal occurrences have regional-scale spatial distributions that are related to Quaternary volcanic centers and shallow earthquake epicenters. Spatial frequency distribution analysis shows that geothermal occurrences have strong positive spatial associations with Quaternary volcanic centers, Quaternary volcanic rocks, quasi-gravity lows, and NE-, NNW-, WNW-trending faults. These geological features, with their strong positive spatial associations with geothermal occurrences, constitute spatial recognition criteria of regional-scale geothermal potential in a study area. Application of data-driven evidential belief functions in GIS-based predictive mapping of regional-scale geothermal potential resulted in delineation of high potential zones occupying 25% of West Java, which is a substantial reduction of the search area for further exploration of geothermal resources. The predicted high potential zones delineate about 53-58% of the training geothermal areas and 94% of the validated geothermal occurrences. The results of this study demonstrate the value of regional-scale geothermal potential mapping in: (a) data-poor situations, such as West Java, and (b) regions with geotectonic environments similar to the study area. (author)

  14. Geothermal potential of West-Central New Mexico from geochemical and thermal gradient data

    Energy Technology Data Exchange (ETDEWEB)

    Levitte, D.; Gambill, D.T.

    1980-11-01

    To study the low temperature and Hot Dry Rock (HDR) geothermal potential of west-central New Mexico, 46 water samples were collected and geothermal gradient measurements were made in 29 wells. Water chemistry data indicate that all the samples collected are meteoric waters. High temperatures of samples taken from wells between Gallup and Tohatchi indicate these wells may derive water from a warm aquifer below the depth of the wells. The chemistries of the samples farther south on the Zuni Indian reservation suggest these waters are not circulating below 600 m of the surface. Geothermometry calculations support the conclusion that the waters sampled are meteoric. The geothermometry also indicates that the deep reservoir between Gallup and Tohatchi may be greater than 60/sup 0/C. Thermal gradient data indicate an area of high gradient on the Zuni Indian Reservation with a measured maximum of 67/sup 0/C/km between 181 m and 284 m. This high probably is not hydrologically controlled. The maximum gradients in the study area are 76/sup 0/C/km and 138/sup 0/C/km, measured just east of Springerville, Arizona. These gradients are undoubtedly controlled by circulating water, possibly heated by a magmatic source at depth and circulating back to the surface.

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

    Science.gov (United States)

    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

  16. Updates to Enhanced Geothermal System Resource Potential Estimate

    Energy Technology Data Exchange (ETDEWEB)

    Augustine, Chad

    2017-05-01

    The deep EGS electricity generation resource potential estimate maintained by the National Renewable Energy Laboratory was updated using the most recent temperature-at-depth maps available from the Southern Methodist University Geothermal Laboratory. The previous study dates back to 2011 and was developed using the original temperature-at-depth maps showcased in the 2006 MIT Future of Geothermal Energy report. The methodology used to update the deep EGS resource potential is the same as in the previous study and is summarized in the paper. The updated deep EGS resource potential estimate was calculated for depths between 3 and 7 km and is binned in 25 degrees C increments. The updated deep EGS electricity generation resource potential estimate is 4,349 GWe. A comparison of the estimates from the previous and updated studies shows a net increase of 117 GWe in the 3-7 km depth range, due mainly to increases in the underlying temperature-at-depth estimates from the updated maps.

  17. Preliminary Assessment of Geothermal Resource Potential at the UTTR

    Energy Technology Data Exchange (ETDEWEB)

    Richard P. Smith, PhD., PG; Robert P. Breckenridge, PhD.; Thomas R. Wood, PhD.

    2011-06-01

    The purpose of this report is to summarize the current state of geologic knowledge concerning potential high-temperature geothermal development on the lands controlled by Hill Air Force Base (HAFB) at the Utah Testing and Training Range (UTTR) and the lands encompassed by the Dugway Proving Grounds (Dugway). This report is based on currently available published and publically available information. Most of the information presented here is purely geologic in nature. Therefore, the logistical issues (such as military exclusion areas, proximity to electrical infrastructure, and access) are additional considerations that are being addressed in a separate report that will be issued to HAFB by the SES corporation.

  18. The potential for geothermal energy in the United Kingdom

    Energy Technology Data Exchange (ETDEWEB)

    Downing, R.A.

    1985-01-01

    This work is a review of goethermal prospects in the UK. The book summarizes the results of an investigation of Britain's geothermal energy potential by the British Geological Survey between 1977 and 1984, supported by the Department of Energy and the EEC. The assessment covers both resources and the prospects for their development. Hot groundwaters in deep sedimentary basins and heat stored in 'hot dry rocks' are considered. The structure of the basins and the nature and properties of the sediments they contain are described and illustrated with maps and diagrams.

  19. Evolution of Middle-Low Temperature Carbonate Geothermal System in Taiyuan, Northern China%太原盆地区碳酸盐岩中—低温地热系统演化

    Institute of Scientific and Technical Information of China (English)

    马腾; 王焰新; 马瑞; 闫春淼; 单慧媚; 陈柳竹

    2012-01-01

    To study the complicated issue of interactions between carbonate geothermal system with mid-low temperature existing in Taiyuan basin and its surrounding karst system existing in mountains, the geological evolution processes of the carbonate geothermal system were remodeled based on the analysis of geological structure and characterization of hydrochemistry and iso-topic compositions of the karst water. We come to the following conclusions: (1) The carbonate geothermal system with mid-low temperature has experienced five stages of geological evolution since Yanshan Movement, and it separated from its surrounding karst system in mountains during the stable sedimentation period of Neogene to the Early Pleistocene, and then they evolved respectively; (2) The karstification of the carbonate geothermal system with mid-low temperature were due to the following two factors: ? Rainfall of the late Middle Pleistocene and the early Late Pleistocene infiltrated along the fault zone (e. G. Fenhe fault), reacted with the metal sulfide in C-P coal measure strata and formed the groundwater rich in sulfuric acid. The groundwater was recharged to the carbonated geothermal reservoir and mixed with the older karst water stored in it, which facilitated the dissolution of carbonate rock; (2) the pyrolyzation of carbonated rock occurred by the baking of magma from the basin basement in the late Middle Pleistocene and the early Late Pleistocene; (3) The karst water in the geothermal system formed in the late Middle Pleistocene and the early Late Pleistocene, and sealed up to now because of the good insulation of its overlying strata. Mainly controlled by the geological structure, its east-west boundaries were Dongshan fault and Xishan faultrespectively and its south-north boundaries were Tianzhuang fault and north boundary of Qinxian horst respectively%针对太原盆地区碳酸盐岩中—低温地热系统与边山岩溶水系统的相互作用关系这一难点问题,以地质构造

  20. Utilization of low-temperature heat sources for heat and power production

    DEFF Research Database (Denmark)

    Haglind, Fredrik; Elmegaard, Brian

    2014-01-01

    Low-temperature heat sources are available in many applications, ranging from waste heat from marine diesel engines, industries and refrigeration plants to biomass, geothermal and solar heat sources. There is a great potential for enhancing the utilization of these heat sources by novel thermodyn......Low-temperature heat sources are available in many applications, ranging from waste heat from marine diesel engines, industries and refrigeration plants to biomass, geothermal and solar heat sources. There is a great potential for enhancing the utilization of these heat sources by novel.......Both power production and heat pumps may benefit from the development as both technologies utilize a heat source. This makes it possible to cover the complete temperature range of low temperature sources. The development may contribute to significantly lower energy consumption in Danish industry and shipping...

  1. CONSUMER POTENTIAL ANALYSIS OF FEASIBILITY CRITERIA OF GEOTHERMAL PROJECTS

    OpenAIRE

    Jenei, Tunde

    2012-01-01

    The University of Debrecen, Faculty of Engineering, has been conducting a research program in geothermal energy since 2008. This program enabled me to devise an analytical study of the monetary and non-monetary criteria of geothermal projects. The monetary criteria of a region or a location for geothermal energy production cover the investment costs of the surface installations and the cost of the drillings. Non-monetary criteria include the geological and geothermal evaluations of a reservoi...

  2. Thermodynamic Analysis of a Rankine Cycle Powered Refrigeration System Using Low-Temperature Geothermal Energy%基于有机朗肯循环的低温地热制冷系统热力学分析

    Institute of Scientific and Technical Information of China (English)

    胡冰; 马伟斌

    2014-01-01

    为有效利用低温地热资源,本文以有机朗肯-蒸汽压缩制冷系统为研究对象,建立了系统的热力学模型,分析比较了分别以R290、R600、R600a、R601、R601a和R1270为工质时的系统性能,并以系统整体COP和每kW制冷量所对应的工质流量为关键指标对工质进行了优选。分析结果表明:当地热水温度为60℃~90℃、冷凝温度为30℃~55℃、蒸发温度为-15℃~15℃时,R601是系统的最佳工质。当地热水温度为90℃,其余参数为典型工况值时,工质R601所对应的系统性能系数COP为0.49。%To efficiently utilize low-temperature geothermal energy, an organic Rankine cycle-vapor compression refrigeration (ORC-VCR) system was employed and a thermodynamic model was developed. Six working fluids of R290, R600, R600a, R601, R601a and R1270 were analyzed and evaluated in order to identify suitable working fluids which may yield high system efficiencies. The overall COP and working fluid mass flow rate of per kW cooling capacity are chosen as key performance indicators. The calculated results show that R601 is the best working fluid for the ORC-VCR system as the geothermal water temperature is between 60oC and 90oC, the condensation temperature ranges from 30oC to 55oC and the evaporation temperature varies from 30oC to 55oC. When the geothermal water temperature reaches 90oC and the other input parameters are in typical values, the overall COP of the R601 case reaches 0.49.

  3. Geothermal reservoir monitoring by continuous self-potential measurements, Mori geothermal field, Japan

    Energy Technology Data Exchange (ETDEWEB)

    Yasukawa, Kasumi; Ishido, Tsuneo [Geological Survey of Japan, AIST, Central 7, Tsukuba, Ibaraki 305-8567 (Japan); Suzuki, Iwao [JMC Geothermal Engineering Co. Ltd, Iwate (Japan)

    2005-10-01

    A self-potential (SP) monitoring study was conducted at the Mori geothermal field, Japan, to detect fluid flow changes in the reservoir caused by well operations. In 2000, eight observation points were deployed in and around the reservoir region for about 2.5 months, during which the production and reinjection wells were shut in and then re-opened. Since no reliable remote reference was available, the SP results were plotted in two ways: adopting an observation point in the target area as reference, and using the average value of all the observation points as a reference (called the 'relative SP' plot). Although changes in SP corresponding to well operations were detected in both plots, more reliable results were obtained with the relative SP plot. Based on numerical simulation of SP using a simplified model of the Mori reservoir, the observed changes are interpreted as being caused by reservoir pressure changes through electrokinetic coupling. (author)

  4. 低温热管地热利用试验及数值模拟%Experiment and numerical simulation on geothermal utilization based on low temperature heat pipe

    Institute of Scientific and Technical Information of China (English)

    郑广瑞; 杨峻

    2011-01-01

    To solve the soil freezing problem around the pipes for cryogenic fluid, the low temperature heat pipe technology is adopted to effectively utilize geothermal energy: Basing on analyzing the temperature pattern in the soil freezing theoretically, the initial experiment and numerical simulation calculation are introduced. The result of numerical simulation calculation is in general accordance with the experimental data, which could provide reference for solving the practical engineering problems.%采用低温热管技术有效利用地热,可解决输送低温流体埋地管道周围土壤的冻胀问题.对冻土层的温度场进行理论分析,并开展初步试验研究和数值模拟计算,模拟结果与试验值基本一致,为解决工程实际问题提供一定参考.

  5. On reasons for leakage in low-temperature water geothermal heating toilets and its prevention%低温热水地热采暖卫生间渗漏原因及防治

    Institute of Scientific and Technical Information of China (English)

    张芳莲

    2011-01-01

    The paper analyzes the leakage problems in the low-temperature water geothermal heating toilets,illustrates the reasons for the leakage from the floor compactness,the construction of the waterproof layer,the packing layer,and the treatment of the leveling blanket,points out the respective prevention measures,and points out the waterproof treatment of the toilets can do well in the blocking and the direction,and pay attention to the quality control in the construction process.%针对低温热水地热采暖卫生间渗漏问题进行了分析,从楼板密实性、防水层施工、填充层及找平层处理等方面入手阐述了渗漏的原因,提出了相应的预防措施,并指出卫生间的防水处理应做好堵和导两方面,注意施工过程中质量控制。

  6. 低温地热井+热泵机组供暖的经济性分析%Economic Analysis of the Heating with Low Temperature Geothermal Well and Heat Pump Units

    Institute of Scientific and Technical Information of China (English)

    焦宏照; 李英; 王娜

    2016-01-01

    针对无市政供暖建筑,分析了采用何种供暖方式更加经济、可靠。探讨了2种低温地热井+热泵机组、燃气真空锅炉、电热真空锅炉、空气源热泵等采暖形式,结合工程实例和一些假定条件,从系统初投资、运行费用、寿命周期,以及初投资与运行费用之和等方面进行比较分析,并得出结论。%The more suitable, economical and reliable heating modesare analyzed for buildings without a municipal heating. Combined with engineering examples and some assumptions, several heating modes including two kinds of low temperature geothermal well and heat pump units, gas vacuum boiler, electric heating vacuum boiler, and air source heat pump are expounded and compared from the initial investment, operating expenses, life cycle, operating expenses, even the sum ofthe initial investment and operating expenses.

  7. Sperry low-temperature geothermal conversion system. Volume I. Organic-working-fluid properties. Final report. [R-114, 1,2-dichlorotetrafluorethane

    Energy Technology Data Exchange (ETDEWEB)

    Carroll, C.; Hules, K.R.; Langley, R.; Toekes, B.; Wilson, D.P.

    1981-01-01

    Measurements of the physical properties of R-114 in the compressed liquid and dense gas regions are reported. Included are: experimental studies of the thermodynamic properties of R-114, enthalpy measurement by throttling experiment, engineering model of the thermodynamic properties of R-114, feasibility study to dissociate R-114 with a four-cycle gasoline engine, transport properties of R-114, analytical procedure to determine impurities in R-114, toxicological information on Freons, and a literature search of published properties of R-114, other refrigerants, and other potential working fluids. (LEW)

  8. Hot springs and the geothermal energy potential of Jammu & Kashmir State, N.W. Himalaya, India

    Science.gov (United States)

    Craig, J.; Absar, A.; Bhat, G.; Cadel, G.; Hafiz, M.; Hakhoo, N.; Kashkari, R.; Moore, J.; Ricchiuto, T. E.; Thurow, J.; Thusu, B.

    2013-11-01

    India has an estimated geothermal power potential of 10,600 MWe, but this potential is entirely undeveloped at present. The 'Geothermal Atlas of India' prepared by the Geological Survey of India (GSI) in 1991 describes some 340 hot spring sites and identifies more than 300 sites with geothermal potential in at least seven key geothermal provinces throughout India. There are more than 20 hot spring sites in Jammu & Kashmir State, mainly in the Chenab Valley in the Lesser/Central Himalaya, the Kashmir Valley and in the High Himalaya region of Ladakh. At least three localities in the Ladakh region - Chamuthang and Puga in the Indus valley and Panamik in the Nubra Valley - are considered to have geothermal power generation potential of between 3 and > 20 MWe.

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

    Science.gov (United States)

    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 (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 Dublin. Over the Galway granite, MT and AMT data have been collected at a total of 75 sites (33 consist of only

  10. Geothermal systems in volcanic arcs: Volcanic characteristics and surface manifestations as indicators of geothermal potential and favorability worldwide

    Science.gov (United States)

    Stelling, P.; Shevenell, L.; Hinz, N.; Coolbaugh, M.; Melosh, G.; Cumming, W.

    2016-09-01

    This paper brings a global perspective to volcanic arc geothermal assessments by evaluating trends and correlations of volcanic characteristic and surface manifestation data from world power production sites in subduction zone volcanic settings. The focus of the work was to evaluate volcanic centers individually and as a group in these arcs by correlating various geologic characteristics with known potential to host electricity grade geothermal systems at the volcanic centers. A database was developed that describes key geologic factors expected to be indicative of productive geothermal systems in a global training set, which includes all 74 subduction zone volcanic centers world-wide with current or proven power production capability. Importantly, this data set only contains data from subduction zone volcanoes and contains no negative cases, limiting the populations of any statistical groups. Regardless, this is the most robust geothermal benchmark training set for magmatic-heated systems to date that has been made public. The work reported here is part of a larger project that included data collection, evaluation, correlations and weightings, fairway and favorability modeling and mapping, prediction of blind systems, and uncertainty analysis to estimate errors associated with model predictions. This first paper describes volcano characteristics, compositions and eruption ages and trends along with surface manifestation observations and temperatures as they relate to known power producing systems. Our findings show a strong correlation between the presence and size of active flank fumarole areas and installed power production. Additionally, the majority of volcanic characteristics, including long-held anecdotal correlations related to magmatic composition or size, have limited to no correlation with power production potential. Notable exceptions are correlations between greater power yield from geothermal systems associated with older (Pleistocene) caldera systems

  11. Potential power sources for high-temperature geothermal applications

    Energy Technology Data Exchange (ETDEWEB)

    Guidotti, R.A.; Dobranich, D

    1996-05-01

    The thermal response under geothermal-borehole conditions of a conventional thermal battery was evaluated for various designs by numerical simulations using a finite-element thermal model. This technology, which is based on molten salts, may be suitable as a power source for geothermal borehole applications for data logging. Several promising candidate electrolytes were identified for further study.

  12. Anaerobic fermentation combined with low-temperature thermal pretreatment for phosphorus-accumulating granular sludge: Release of carbon source and phosphorus as well as hydrogen production potential.

    Science.gov (United States)

    Zou, Jinte; Li, Yongmei

    2016-10-01

    Releases of organic compounds and phosphorus from phosphorus-accumulating granular sludge (PGS) and phosphorus-accumulating flocculent sludge (PFS) during low-temperature thermal pretreatment and anaerobic fermentation were investigated. Meanwhile, biogas production potential and microbial community structures were explored. The results indicate that much more soluble chemical oxygen demand (SCOD) and phosphorus were released from PGS than from PFS via low-temperature thermal pretreatment because of the higher extracellular polymeric substances (EPS) content in PGS and higher ratio of phosphorus reserved in EPS. Furthermore, PGS contains more anaerobes and dead cells, resulting in much higher SCOD and volatile fatty acids release from PGS than those from PFS during fermentation. PGS fermentation facilitated the n-butyric acid production, and PGS exhibited the hydrogen production potential during fermentation due to the presence of hydrogen-producing bacteria. Therefore, anaerobic fermentation combined with low-temperature thermal pretreatment can facilitate the recovery of carbon and phosphorus as well as producing hydrogen from PGS.

  13. Potentially exploitable supercritical geothermal resources in the ductile crust

    Science.gov (United States)

    Watanabe, Noriaki; Numakura, Tatsuya; Sakaguchi, Kiyotoshi; Saishu, Hanae; Okamoto, Atsushi; Ingebritsen, Steven E.; Tsuchiya, Noriyoshi

    2017-01-01

    The hypothesis that the brittle–ductile transition (BDT) drastically reduces permeability implies that potentially exploitable geothermal resources (permeability >10−16 m2) consisting of supercritical water could occur only in rocks with unusually high transition temperatures such as basalt. However, tensile fracturing is possible even in ductile rocks, and some permeability–depth relations proposed for the continental crust show no drastic permeability reduction at the BDT. Here we present experimental results suggesting that the BDT is not the first-order control on rock permeability, and that potentially exploitable resources may occur in rocks with much lower BDT temperatures, such as the granitic rocks that comprise the bulk of the continental crust. We find that permeability behaviour for fractured granite samples at 350–500 °C under effective confining stress is characterized by a transition from a weakly stress-dependent and reversible behaviour to a strongly stress-dependent and irreversible behaviour at a specific, temperature-dependent effective confining stress level. This transition is induced by onset of plastic normal deformation of the fracture surface (elastic–plastic transition) and, importantly, causes no ‘jump’ in the permeability. Empirical equations for this permeability behaviour suggest that potentially exploitable resources exceeding 450 °C may form at depths of 2–6 km even in the nominally ductile crust.

  14. Potentially exploitable supercritical geothermal resources in the ductile crust

    Science.gov (United States)

    Watanabe, Noriaki; Numakura, Tatsuya; Sakaguchi, Kiyotoshi; Saishu, Hanae; Okamoto, Atsushi; Ingebritsen, Steven E.; Tsuchiya, Noriyoshi

    2017-01-01

    The hypothesis that the brittle-ductile transition (BDT) drastically reduces permeability implies that potentially exploitable geothermal resources (permeability >10-16 m2) consisting of supercritical water could occur only in rocks with unusually high transition temperatures such as basalt. However, tensile fracturing is possible even in ductile rocks, and some permeability-depth relations proposed for the continental crust show no drastic permeability reduction at the BDT. Here we present experimental results suggesting that the BDT is not the first-order control on rock permeability, and that potentially exploitable resources may occur in rocks with much lower BDT temperatures, such as the granitic rocks that comprise the bulk of the continental crust. We find that permeability behaviour for fractured granite samples at 350-500 °C under effective confining stress is characterized by a transition from a weakly stress-dependent and reversible behaviour to a strongly stress-dependent and irreversible behaviour at a specific, temperature-dependent effective confining stress level. This transition is induced by onset of plastic normal deformation of the fracture surface (elastic-plastic transition) and, importantly, causes no `jump' in the permeability. Empirical equations for this permeability behaviour suggest that potentially exploitable resources exceeding 450 °C may form at depths of 2-6 km even in the nominally ductile crust.

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

    Energy Technology Data Exchange (ETDEWEB)

    Allison, Lee [Executive Office of the State of Arizona (Arizona Geological Survey); Richard, Stephen [Executive Office of the State of Arizona (Arizona Geological Survey); 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

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

    Energy Technology Data Exchange (ETDEWEB)

    None

    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

  17. Geothermal resources in California: the problems and the potential

    Energy Technology Data Exchange (ETDEWEB)

    1973-01-01

    The report is presented under the following section headings: introduction; conclusions and recommendations; legislative activity in 1973; United Nations Geothermal Conference; International Geothermal Conference--1975; National Conference on Geothermal Energy, May 10--11, Palm Springs, Calif.; Imperial Valley field trip and joint interim hearing October 16--17, 1973 (Senate Committee on Natural Resources and Wildlife on Senate Bill 577 in San Diego); hearing of the Subcommittee on Geothermal Resources and the Senate Committee on Public Utilities and Corporations, Nov. 12, 1973 in San Francisco (public access to steam at The Geysers); hearing of the Senate Committee on Natural Resources and Wildlife on the continued availability of natural gas and other sources of energy, Nov. 15, 1973, in Martinez, Calif; and Appendix. (JGB)

  18. The Gabbs Valley, Nevada, geothermal prospect: Exploring for a potential blind geothermal resource

    Science.gov (United States)

    Payne, J.; Bell, J. W.; Calvin, W. M.

    2012-12-01

    The Gabbs Valley prospect in west-central Nevada is a potential blind geothermal resource system. Possible structural controls on this system were investigated using high-resolution LiDAR, low sun-angle aerial (LSA) photography, exploratory fault trenching and a shallow temperature survey. Active Holocene faults have previously been identified at 37 geothermal systems with indication of temperatures greater than 100° C in the western Nevada region. Active fault controls in Gabbs Valley include both Holocene and historical structures. Two historical earthquakes occurring in 1932 and 1954 have overlapping surface rupture patterns in Gabbs Valley. Three active fault systems identified through LSA and LiDAR mapping have characteristics of Basin and Range normal faulting and Walker Lane oblique dextral faulting. The East Monte Cristo Mountains fault zone is an 8.5 km long continuous NNE striking, discrete fault with roughly 0.5 m right-normal historic motion and 3 m vertical Quaternary separation. The Phillips Wash fault zone is an 8.2 km long distributed fault system striking NE to N, with Quaternary fault scarps of 1-3 m vertical separation and a 500 m wide graben adjacent to the Cobble Cuesta anticline. This fault displays ponded drainages, an offset terrace riser and right stepping en echelon fault patterns suggestive of left lateral offset, and fault trenching exposed non-matching stratigraphy typical of a significant component of lateral offset. The unnamed faults of Gabbs Valley are a 10.6 km long system of normal faults striking NNE and Quaternary scarps are up to 4 m high. These normal faults largely do not have historic surface rupture, but a small segment of 1932 rupture has been identified. A shallow (2 m deep) temperature survey of 80 points covering roughly 65 square kilometers was completed. Data were collected over approximately 2 months, and continual base station temperature measurements were used to seasonally correct temperature measurements. A 2

  19. Low temperature asphalt mixtures

    OpenAIRE

    Modrijan, Damjan

    2006-01-01

    This thesis presents the problem of manufacturing and building in the asphalt mixtures produced by the classical hot procedure and the possibility of manufacturing low temperature asphalt mixtures.We will see the main advantages of low temperature asphalt mixtures prepared with bitumen with organic addition Sasobit and compare it to the classical asphalt mixtures. The advantages and disadvantages of that are valued in the practical example in the conclusion.

  20. Low temperature creep plasticity

    Directory of Open Access Journals (Sweden)

    Michael E. Kassner

    2014-07-01

    Full Text Available The creep behavior of crystalline materials at low temperatures (T < 0.3Tm is discussed. In particular, the phenomenological relationships that describe primary creep are reviewed and analyzed. A discussion of the activation energy for creep at T < 0.3Tm is discussed in terms of the context of higher temperature activation energy. The basic mechanism(s of low temperature creep plasticity are discussed, as well.

  1. Estimating Limits for the Geothermal Energy Potential of Abandoned Underground Coal Mines: A Simple Methodology

    Directory of Open Access Journals (Sweden)

    Rafael Rodríguez Díez

    2014-07-01

    Full Text Available Flooded mine workings have good potential as low-enthalpy geothermal resources, which could be used for heating and cooling purposes, thus making use of the mines long after mining activity itself ceases. It would be useful to estimate the scale of the geothermal potential represented by abandoned and flooded underground mines in Europe. From a few practical considerations, a procedure has been developed for assessing the geothermal energy potential of abandoned underground coal mines, as well as for quantifying the reduction in CO2 emissions associated with using the mines instead of conventional heating/cooling technologies. On this basis the authors have been able to estimate that the geothermal energy available from underground coal mines in Europe is on the order of several thousand megawatts thermal. Although this is a gross value, it can be considered a minimum, which in itself vindicates all efforts to investigate harnessing it.

  2. The Potential Impacts on Aquatic Ecosystems from the Release of Trace Elements in Geothermal Fluids

    Energy Technology Data Exchange (ETDEWEB)

    Cushman, R.M.

    2000-03-14

    Geothermal energy will likely constitute an increasing percentage of our nation's future energy ''mix,'' both for electrical and nonelectrical uses. Associated with the exploitation of geothermal resources is the handling and disposal of fluids which contain a wide variety of potentially toxic trace elements. We present analyses of 14 trace elements found in hydrothermal fluids from various geothermal reservoirs in the western United States. The concentrations of these elements vary over orders of magnitude between reservoirs. Potential impacts are conservatively assessed on the basis of (1) toxicity to freshwater biota, and (2) bioaccumulation in food fish to the point where consumption might be hazardous to human health. Trace element concentrations generally range from benign levels to levels which might prove toxic to freshwater biota and contaminate food fisheries. We stress the need for site-specific analyses and careful handling of geothermal fluids in order to minimize potential impacts.

  3. Using Facilities And Potential Of Geothermal Resources In The Canakkale Province - NW Turkey

    Science.gov (United States)

    Deniz, Ozan; Acar Deniz, Zahide

    2016-04-01

    Turkey, due to its geological location, has a rich potential in point of geothermal resources. Çanakkale province is located northwestern (NW) part of Turkey and it has important geothermal fields in terms of geothermal energy potential. Geothermal resources reach to the surface both effects of past volcanic activity and extensions of fault zones associated with complex tectonic systems in the region. The aim of this study is to summarize hydrogeochemical characteristics, using facilities and potential of hot springs and spas located in the Çanakkale province. There are 13 geothermal fields in the region and the surface temperatures of hot springs are ranging between 28 centigrade degree and 175 centigrade degree. Hydrogeochemical compositions of thermal water display variable chemical compositions. Na, Ca, SO4, HCO3 and Cl are the dominant ions in these waters. Thermal waters of Tuzla and Kestanbol geothermal fields which is located the near coastal area can be noted NaCl type. Because these two geothermal waters have high TDS values, scaling problems are seen around the hot springs and pipelines. Geothermal waters in the province are meteoric origin according to oxygen-18, deuterium and tritium isotopes data. Long underground residence times of these waters and its temperatures have caused both more water - rock interaction and low tritium values. Geothermal energy is utilized in many areas in Turkey today. It is generally used for space heating, balneotherapy and electricity generation. Explorations of geothermal resources and investments in geothermal energy sector have risen rapidly in the recent years particularly in western Turkey. High-temperature geothermal fields are generally located in this region related to the Aegean Graben System and the North Anotalian Fault Zone. All geothermal power plants in Turkey are located in this region. Considering the Çanakkale province, most geothermal fields are suitable for multipurpose usage but many of them have

  4. Geothermal energy: an important resource

    National Research Council Canada - National Science Library

    Dowling, Carolyn B; Neumann, Klaus; Florea, Lee J

    2016-01-01

    .... Contributions include studies on the feasibility of integrating geological modeling with system design, extraction of low-temperature geothermal energy in underground coal mines, ground-source heat...

  5. Geothermal heat potential - the source for heating greenhouses in Southestern Europe

    Directory of Open Access Journals (Sweden)

    Urbancl Danijela

    2016-01-01

    Full Text Available The paper presents economically evaluated solutions for heating greenhouses with geothermal potential, if the same greenhouse is placed in two different locations in Southeastern Europe, one in Slovenia and the other in Serbia. The direct geothermal water exploitation using heat exchangers is presented and the remaining heat potential of already used geothermal water is exploited using high temperature heat pumps. Energy demands for heating greenhouses are calculated considering climatic parameters of both locations. Furthermore, different constructions materials are taken into account, and energy demands are evaluated if the same greenhouse is made of 4 mm toughened single glass, double insulated glass or polycarbonate plates. The results show that the geothermal energy usage is economically feasible in both locations, because payback periods are in range from two to almost eight years for different scenarios.

  6. The Pyrexia transient receptor potential channel mediates circadian clock synchronization to low temperature cycles in Drosophila melanogaster.

    Science.gov (United States)

    Wolfgang, Werner; Simoni, Alekos; Gentile, Carla; Stanewsky, Ralf

    2013-10-07

    Circadian clocks are endogenous approximately 24 h oscillators that temporally regulate many physiological and behavioural processes. In order to be beneficial for the organism, these clocks must be synchronized with the environmental cycles on a daily basis. Both light : dark and the concomitant daily temperature cycles (TCs) function as Zeitgeber ('time giver') and efficiently entrain circadian clocks. The temperature receptors mediating this synchronization have not been identified. Transient receptor potential (TRP) channels function as thermo-receptors in animals, and here we show that the Pyrexia (Pyx) TRP channel mediates temperature synchronization in Drosophila melanogaster. Pyx is expressed in peripheral sensory organs (chordotonal organs), which previously have been implicated in temperature synchronization. Flies deficient for Pyx function fail to synchronize their behaviour to TCs in the lower range (16-20°C), and this deficit can be partially rescued by introducing a wild-type copy of the pyx gene. Synchronization to higher TCs is not affected, demonstrating a specific role for Pyx at lower temperatures. In addition, pyx mutants speed up their clock after being exposed to TCs. Our results identify the first TRP channel involved in temperature synchronization of circadian clocks.

  7. Unlocking the potential of supported liquid phase catalysts with supercritical fluids: low temperature continuous flow catalysis with integrated product separation.

    Science.gov (United States)

    Franciò, Giancarlo; Hintermair, Ulrich; Leitner, Walter

    2015-12-28

    Solution-phase catalysis using molecular transition metal complexes is an extremely powerful tool for chemical synthesis and a key technology for sustainable manufacturing. However, as the reaction complexity and thermal sensitivity of the catalytic system increase, engineering challenges associated with product separation and catalyst recovery can override the value of the product. This persistent downstream issue often renders industrial exploitation of homogeneous catalysis uneconomical despite impressive batch performance of the catalyst. In this regard, continuous-flow systems that allow steady-state homogeneous turnover in a stationary liquid phase while at the same time effecting integrated product separation at mild process temperatures represent a particularly attractive scenario. While continuous-flow processing is a standard procedure for large volume manufacturing, capitalizing on its potential in the realm of the molecular complexity of organic synthesis is still an emerging area that requires innovative solutions. Here we highlight some recent developments which have succeeded in realizing such systems by the combination of near- and supercritical fluids with homogeneous catalysts in supported liquid phases. The cases discussed exemplify how all three levels of continuous-flow homogeneous catalysis (catalyst system, separation strategy, process scheme) must be matched to locate viable process conditions.

  8. Resource assessment for geothermal direct use applications

    Energy Technology Data Exchange (ETDEWEB)

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

    1984-04-01

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

  9. Extended geothermal potential of clastic aquifers by hydraulic stimulation

    NARCIS (Netherlands)

    Veldkamp, J.G.; Pluymaekers, M.P.D.; Wees, J.D.A.M.

    2014-01-01

    We evaluated the implications of hydraulic stimulation in a Dutch context for low permeability clastic aquifers at a depth of 2000 to 4000 m, whose transmissivity has been mapped in the framework of the Dutch subsurface information system on geothermal energy in the Netherlands. For the simulation a

  10. SELF-POTENTIAL SURVEY AT THE CERRO PRIETO GEOTHERMAL FIELD, BAJA CALIFORNIA, MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Corwin, R.F.; Diaz C., S.; Rodriguez B., J.

    1978-06-01

    In December 1977, two self-potential survey lines were run across the producing area of the Cerro Prieto geothermal field, located about 30 km south of Mexicali, Baja California, Mexico. The purpose of the survey was to determine whether significant self-potential variations were related to the known geothermal activity. Large-amplitude, long-wavelength self-potential anomalies are seen in the Cerro Prieto geothermal field. The inflection points of the anomalies are roughly centered over two major faults thought to act as conduits for the thermal fluids, and the form of the anomalies indicates that they may be generated by electrical activity extending to a depth of several km along the fault zones. Thus, self-potential measurements may be helpful in tracing thermally active fault zones in the Cerro Prieto area.

  11. Renewable hot dry rock geothermal energy source and its potential in Pakistan

    Energy Technology Data Exchange (ETDEWEB)

    Zaigham, Nayyer Alam [Department of Geology, University of Karachi, Karachi 75270 (Pakistan); Nayyar, Zeeshan Alam [Department of Applied Physics, University of Karachi, Karachi 75270 (Pakistan)

    2010-04-15

    Geothermal energy source, one of the viable renewable energy sources, has encouraging potential to generate full base-load electricity, which has not been explored so far in Pakistan. Though the country can be benefited by harnessing the hydro-geothermal options of energy generation in areas where sources exist, but most of these sources lie in extreme remote and inaccessible rugged mountainous ranges away from the urban-industrial centers. On the other hand, the present study shows that the HDR geothermal option is one of the most viable renewable sources considering the tectonic setup of Pakistan. Results of the study highlight the HDR geothermal energy prospects at relatively deeper depths than hydro-geothermal resources in water-free condition. The basement tectonic analyses reveal that the HDR prospects could be found even just below the urban-industrial centers of Pakistan where there are no hot springs and/or geysers like southern Indus basin in Sindh province or the Kharan trough in the western Balochistan province. Presence of high earth-skin temperature gradient trends derived from satellite temperature data and the high geothermal gradient anomalous zone derived from scanty data of bottom-hole temperatures of some of the oil and gas exploratory wells, indicates encouraging prospects for HDR energy sources in southern Indus and Thar Desert regions inclusive of Karachi synclinorium area. These high geothermal gradients have been inferred to be the result of the deep-seated southern Indus and the Thar fossil-rift structures. Moreover, the prospects of the HDR geothermal energy sources have also been inferred in the Chagai Arc region and the Kharan-Panjgur tectonic depression in the western part of Pakistan based on the analysis of integrated geophysical data. If HDR prospects are developed, they can offer the sustainable, CO{sub 2}-free and independent of time, of day, of weather or season, and the base-load energy-generation resource. (author)

  12. Potential for hot-dry-rock geothermal resources: Experimental results

    Science.gov (United States)

    Rowley, J. C.; Heiken, G.; Murphy, H. D.; Kuriyagawa, M.

    Hot dry rock (HDR) contains insufficient permeability and fluid for natural hydrothermal development, but water pumped in a circulation loop through a HDR reservoir (hydraulically fractured between two drill holes) is being tested and evaluated. The formation of such in situ heat transfer systems, and subsequent testing of the man-made geothermal reservoirs in the Jemez volcanic field, New Mexico have already indicated the technical feasibility of the hot dry rock (HDR) geothermal concept. Documented production history and heat-extraction data obtained during the period from 1978 to 1980 have confirmed heat transfer, low water loss, and predictable thermal drawdown models for the HDR systems. During a nine month test of closed-loop heat extraction operations, 15 x 10 to the 6th power kWh of thermal energy were produced. The effective heat-transfer area and volume of the reservoir increased due to secondary fracturing caused by thermal contraction of the reservoir rock, and sustained pressurization. Drilling, fracturing, and testing of a larger, hotter reservoir system is now underway on a HDR geothermal reservoir of commercial size.

  13. Investigation of the Mount Tongariro, New Zealand, geothermal system through Self Potential mapping

    Science.gov (United States)

    Miller, C. A.

    2013-12-01

    Mount Tongariro volcano is a composite of overlapping vents active since c. 275 ka with 6 main periods of cone building. The volcano hosts an active geothermal system thought to be vapour dominated with a capping condensate layer; active surface geothermal features are present at Ketetahi, Red Crater, Central Crater and Te Maari Craters. Mount Tongariro erupted twice at Upper Te Maari Crater in 2012 after 125 years of dormancy. The first eruption (August 6th) is thought to be triggered from uncapping of the geothermal system by a landslide caused by pore pressure changes due to dyke intrusion. In response to those eruptions I undertook a combined Self Potential (SP), soil CO2 and ground temperature survey to learn more about the geothermal system, its distribution and fluid flow patterns. Analysis of SP vs. topographic gradient delineated the Ketetahi and Red Crater geothermal surface features. I propose that low pH fluids, combined with hydrothermally altered and therefore electrically conductive ground are the dominate cause of subdued SP anomalies around these features. I interpret a large positive anomaly (+1100 mV) in Oturere Valley, which has no surface geothermal activity, to result from deepening of a ground water aquifer beneath a thick electrically resistive lava flow. Subsequent modelling of SP data to estimate both water table depth, and depth to a potential current source agree with the inferred thickness of the Oturere Valley lava flow, and imply that the lava flow is a poor aquifer. Therefore underlying material hosts the aquifer. Finally I interpret a large negative (-600 mV) SP anomaly on the NE flank of North Crater as a zone of down flowing meteoric fluids, situated outside of the geothermal system. The geothermal surface features with subdued SP anomalies resulting from low pH fluids and conductive hydrothermally altered ground, map zones of weakened rock. These zones may be prone to future flank collapse, especially in areas of steep topography

  14. Assessment of the geothermal/geopressure potential of the Gulf Coastal Plan of Alabama. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, G.V.; Wang, G.C.; Mancini, E.A.; Benson, D.J.

    1980-01-01

    Geothermal and geopressure as well as geologic and geophysical data were studied to evaluate the potential for future development of geothermal resources underlying the Alabama Coastal Plain. Wire-line log data compiled and interpreted from more than 1300 oil and gas test wells included maximum recorded temperatures, mud weights, rock resistivities as related to geopressure, formation tops, fault locations, and depths to basement rock. The Alabama Coastal Plain area is underlain by a conduction dominated, deep sedimentary basin where geothermal gradients are low to moderate (1.0 to 1.8/sup 0/F/100 feet). In some areas of southwest Alabama, abnormally high temperatures are found in association with geopressured zones within the Haynesville Formation of Jurassic age; however, rocks of poor reservoir quality dominate this formation, with the exception of a 200-square-mile area centered in southernmost Clarke County where a porous and permeable sand unit is encased within massive salt deposits of the lower Haynesville. The results of a petrograhic study of the Smackover Formation, which underlies the Haynesville, indicate that this carbonate rock unit has sufficient porosity in some areas to be considered a potential geothermal reservoir. Future development of geothermal resources in south Alabama will be restricted to low or moderate temperature, non-electric applications, which constitute a significant potential energy source for applications in space heating and cooling and certain agricultural and industrial processes.

  15. Assessment of the geothermal/geopressure potential of the Gulf Coastal Plan of Alabama. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, G.V.; Wang, G.C.; Mancini, E.A.; Benson, D.J.

    1980-01-01

    Geothermal and geopressure as well as geologic and geophysical data were studied to evaluate the potential for future development of geothermal resources underlying the Alabama Coastal Plain. Wire-line log data compiled and interpreted from more than 1300 oil and gas test wells included maximum recorded temperatures, mud weights, rock resistivities as related to geopressure, formation tops, fault locations, and depths to basement rock. The Alabama Coastal Plain area is underlain by a conduction dominated, deep sedimentary basin where geothermal gradients are low to moderate (1.0 to 1.8/sup 0/F/100 feet). In some areas of southwest Alabama, abnormally high temperatures are found in association with geopressured zones within the Haynesville Formation of Jurassic age; however, rocks of poor reservoir quality dominate this formation, with the exception of a 200-square-mile area centered in southernmost Clarke County where a porous and permeable sand unit is encased within massive salt deposits of the lower Haynesville. The results of a petrograhic study of the Smackover Formation, which underlies the Haynesville, indicate that this carbonate rock unit has sufficient porosity in some areas to be considered a potential geothermal reservoir. Future development of geothermal resources in south Alabama will be restricted to low or moderate temperature, non-electric applications, which constitute a significant potential energy source for applications in space heating and cooling and certain agricultural and industrial processes.

  16. The effect of low-temperature pretreatment on the solubilization and biomethane potential of microalgae biomass grown in synthetic and wastewater media.

    Science.gov (United States)

    Kinnunen, V; Rintala, J

    2016-12-01

    Microalgae have been suggested as a sustainable raw material for biofuel production in the form of methane via anaerobic digestion. Here, pretreatments at 60-80°C were investigated, aiming to study the impact of algae culture media on biomethane potential and pretreatment efficiency. Chlorella vulgaris and mixed culture of native algae species (dominating by Scenedesmus sp.) were grown in synthetic medium, wastewater (sterilized and non-sterilized) and digestate from anaerobic digestion of pulp and paper biosludge (sterilized and non-sterilized). The biomethane potential for native microalgal biomass varied between 154 and 252LCH4kg(-1) VS depending on culture media. The efficiency of the low-temperature pretreatment (80°C, 3h) for solubilization (9-12%) of C. vulgaris and native algae biomass was similar for algae grown in sterilized and non-sterilized wastewater media. The pretreatment increased the biomethane potential of native algae biomass by 11-24%. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Geology and geothermal potential of Alid volcanic center, Eritrea, Africa

    Science.gov (United States)

    Clynne, Michael A.; Duffield, Wendell A.; Fournier, Robert O.; Giorgis, Leake W.; Janik, Cathy J.; Kahsai, Gabreab; Lowenstern, Jacob; Mariam, Kidane W.; Smith, James G.; Tesfai, Theoderos; ,

    1996-01-01

    Alid volcanic center, a 700-meter-tall mountain in Eritrea, northeast Africa, straddles the axis of an active crustal-spreading center called the Danakil Depression. Boiling-temperature fumaroles are common on Alid, and their gas compositions indicate a reservoir temperature of at least 250 ??C. The history of volcanism and the high reservoir temperature indicated by the Alid fumarole gases suggest that a geothermal resource of electrical grade lies beneath the mountain. Though drilling is needed to determine subsurface conditions, the process of dome formation and the ongoing crustal spreading can create and maintain fracture permeability in the hydrothermal system that feeds the Alid fumaroles.

  18. Sustained Low Temperature NOx Reduction

    Energy Technology Data Exchange (ETDEWEB)

    Zha, Yuhui

    2017-04-05

    Increasing regulatory, environmental, and customer pressure in recent years led to substantial improvements in the fuel efficiency of diesel engines, including the remarkable breakthroughs demonstrated through the Super Truck program supported by the U.S. Department of Energy (DOE). On the other hand, these improvements have translated into a reduction of exhaust gas temperatures, thus further complicating the task of controlling NOx emissions, especially in low power duty cycles. The need for improved NOx conversion over these low temperature duty cycles is also observed as requirements tighten with in-use emissions testing. Sustained NOx reduction at low temperatures, especially in the 150-200oC range, shares some similarities with the more commonly discussed cold-start challenge, however poses a number of additional and distinct technical problems. In this project we set a bold target of achieving and maintaining a 90% NOx conversion at the SCR catalyst inlet temperature of 150oC. The project is intended to push the boundaries of the existing technologies, while staying within the realm of realistic future practical implementation. In order to meet the resulting challenges at the levels of catalyst fundamentals, system components, and system integration, Cummins has partnered with the DOE, Johnson Matthey, and Pacific Northwest National Lab and initiated the Sustained Low-Temperature NOx Reduction program at the beginning of 2015. Through this collaboration, we are exploring catalyst formulations and catalyst architectures with enhanced catalytic activity at 150°C; opportunities to approach the desirable ratio of NO and NO2 in the SCR feed gas; options for robust low-temperature reductant delivery; and the requirements for overall system integration. The program is expected to deliver an on-engine demonstration of the technical solution and an assessment of its commercial potential. In the SAE meeting, we will share the initial performance data on engine to

  19. Renewed Volcano-Stratigraphc Studies of Calderas with Geothermal Potential in Mexico

    Science.gov (United States)

    Macias, J. L.; Arce, J. L.; García-Tenorio, F.; Layer, P. W.; Saucedo, R.; Castro, R.; Garduño, V. H.; Jimenez, A.; Pérez, H.; Valdez, G.; Meriggi, L.

    2014-12-01

    During the past six years we have carried out volcanologic fieldwork either in active geothermal fields in Mexico (Los Azufres, Tres Vírgenes, and Cerro Prieto) or in potential sites in which some geothermal exploration studied had been done by the National Power Company (CFE). These studies have been very successful in reassessing the location of the geothermal reservoirs within the volcanic successions through detailed mapping of the volcanic units using high resolution topography and satellite imagery to produce 3-D imagery in conjunction with field work to produce preliminary geologic maps. Detailed stratigraphy of volcanic units, assisted with 40Ar/39Ar and radiocarbon geochronology have redefined the evolution of some of these complexes. For example, our studies at Los Azufres geothermal field located in the State of Michoacán indicate that the volcanic complex of the same name sits upon a structural high transected by E-W faults related to the youngest structures of the Trans-Mexican Volcanic Belt. The volcanic complex has been emplaced during the past ~1.5 Ma. During this time, magmas evolved from basaltic to rhyolitic in composition with the emplacement of circa 100 vents. Several landforms have undergone intense hydrothermal alteration and, in some cases, generated debris avalanches. The revised stratigraphy based on drill holes and new dates of cores suggested that the geothermal reservoir is hosted in Miocene rocks bracketed between the Miocene Sierra de Mil Cumbres volcanics (17-22 Ma) and the products of the volcanic field itself. Similar studies will be carried out at four other Pleistocene calderas (Acoculco, La Primavera, Aguajito and Reforma) attempting to refine their volcanic stratigraphy, evolution, and the location of the geothermal system, and those results will help in the design of exploration strategies for geothermal sources.

  20. Geothermal direct-heat utilization assistance

    Science.gov (United States)

    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.

  1. Prospect Analysis of Medium Low Temperature Geothermal Resource of Xizhang Area%西张地区中低温地热资源利用前景分析

    Institute of Scientific and Technical Information of China (English)

    贾林柱; 钟仁; 张玉宝; 菅德荣

    2012-01-01

    The area is in the north subtropical coastal moist area, monsoon climate prevails,refrigeration is necessary in summer, and heating is necessary in winter. Therefore, for this area the development and utilization of shallow geothermal energy has advantageous natural conditions. In this article, through the survey methods of temperature measurement observations, we studied the distribution regularity of geothermal fields formed by various heat sources with time and space. And the geological structure of Xizhang area was further inferred, the geothermal drilling locations were determined. And then the deep strata structure, heat sources buried depth and fracture reservoir position were inferred by the controlled source earth audio electromagnetic sounding method. Finally, geothermal drilling authentication and single well geothermal resource evaluation were carried out. The results of the study indicate that the use of geothermal resources has a great future.%西张地区为北亚热带沿海湿润气候区域,季风盛行,夏季需要制冷.冬季需要供暖.因此,对于浅层地热能的开发利用具有得天独厚的自然条件.通过地温测量的调查方法,观测和研究地球内部各种热源形成的地热场随时间和空间的分布规律,进一步推断西张家地区地质构造,确定地热钻井位置,再通过可控源大地音频电磁测深方法,推断深部地层结构、热储埋深及断裂位置,确定地热钻井位置,最后进行地热钻井验证和单井地热资源评价.研究结果表明;本区地热资源具有很大的利用前景.

  2. Comprehensive Evaluation of the Geothermal Resource Potential within the Pyramid Lake Paiute Reservation Phase III Report

    Energy Technology Data Exchange (ETDEWEB)

    Noel, Donna [Pyramid Lake Paiute Tribe, Nixon, NV (United States)

    2013-12-01

    This project integrated state-of-the-art exploration technologies with a geologic framework and reservoir modeling to ultimately determine the efficacy of future geothermal production within the PLPT reservation. The information gained during this study should help the PLPT to make informed decisions regarding construction of a geothermal power plant. Additional benefits included the transfer of new technologies and geothermal data to the geothermal industry and it created and/or preserved nearly three dozen jobs accordance with the American Recovery and Reinvestment Act of 2009. A variety of tasks were conducted to achieve the above stated objectives. The following are the tasks completed within the project: 1. Permitting 2. Shallow temperature survey 3. Seismic data collection and analysis 4. Fracture stress analysis 5. Phase I reporting Permitting 7. Shallow temperature survey 8. Seismic data collection and analysis 9. Fracture stress analysis 10. Phase I reporting 11. Drilling two new wells 12. Borehole geophysics 13. Phase II reporting 14. Well testing and geochemical analysis 15. Three-dimensional geologic model 16. Three-dimensional reservoir analysis 17. Reservation wide geothermal potential analysis 18. Phase III reporting Phase I consisted of tasks 1 – 5, Phase II tasks 6 – 8, and Phase III tasks 9 – 13. This report details the results of Phase III tasks. Reports are available for Phase I, and II as separate documents.

  3. Geothermal energy potential for district and process heating applications in the U. S. : an economic analysis

    Energy Technology Data Exchange (ETDEWEB)

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

    1977-08-01

    Geothermal energy is competitive for space and process heating applications over significant distances when employed on a large scale to serve concentrated markets. Under these conditions geothermal energy from 90 to 150/sup 0/C hydrothermal resources should be economically competitive for high-density urban district heating out to distances of 50 miles from the wellhead. Supply curves (price-quantity relationships) were developed for both process heating and district heating applications for distances out to 50 miles. The 90 to 150/sup 0/C hydrothermal resources, which were identified in the assessment of geothermal resources by the U.S. Geological Survey, contain usable energy for space and process heat equivalent to 50 billion barrels of oil. The potential demand for space and process heat near these hydrothermal resources is large; over 10% of the U.S. population resides within 40 miles of the resources. The sensitivity of production costs to the important factors of production was determined. The most important factors are well costs, well flow rate, resource temperature, distance separating demand and supply, population density, size of demand, and the system load factor. Technological advances are needed to reduce costs and increase the distances over which geothermal energy can be competitive. Institutional deterrents to widespread nonelectric applications of geothermal energy will probably be significant. Among these will be the acquisition of rights-of-way, the need to organize concentrated markets, and price competition from the conventional fuels based on average cost rather than marginal cost.

  4. The Marsili Volcanic Seamount (Southern Tyrrhenian Sea: A Potential Offshore Geothermal Resource

    Directory of Open Access Journals (Sweden)

    Francesco Italiano

    2014-06-01

    Full Text Available Italy has a strong geothermal potential for power generation, although, at present, the only two geothermal fields being exploited are Larderello-Travale/Radicondoli and Mt. Amiata in the Tyrrhenian pre-Apennine volcanic district of Southern Tuscany. A new target for geothermal exploration and exploitation in Italy is represented by the Southern Tyrrhenian submarine volcanic district, a geologically young basin (Upper Pliocene-Pleistocene characterised by tectonic extension where many seamounts have developed. Heat-flow data from that area show significant anomalies comparable to those of onshore geothermal fields. Fractured basaltic rocks facilitate seawater infiltration and circulation of hot water chemically altered by rock/water interactions, as shown by the widespread presence of hydrothermal deposits. The persistence of active hydrothermal activity is consistently shown by many different sources of evidence, including: heat-flow data, gravity and magnetic anomalies, widespread presence of hydrothermal-derived gases (CO2, CO, CH4, 3He/4He isotopic ratios, as well as broadband OBS/H seismological information, which demonstrates persistence of volcano-tectonic events and High Frequency Tremor (HFT. The Marsili and Tyrrhenian seamounts are thus an important—and likely long-lasting-renewable energy resource. This raises the possibility of future development of the world’s first offshore geothermal power plant.

  5. Adsorption behavior of modified Iron stick yam skin with Polyethyleneimine as a potential biosorbent for the removal of anionic dyes in single and ternary systems at low temperature.

    Science.gov (United States)

    Zhang, Yan-Zhuo; Li, Jun; Zhao, Jing; Bian, Wei; Li, Yun; Wang, Xiu-Jie

    2016-12-01

    The skin of Iron stick yam (ISY) was modified with Polyethyleneimine (ISY@PEI) and evaluated for use as a potential biosorbent to remove the anionic dyes Sunset yellow (SY), Lemon yellow (LY), and Carmine (CM) from wastewater under low temperature conditions (5-15°C) in single and ternary dye systems. Both in the single and ternary systems, experimental data showed that adsorption capacity reached the highest value at 5°C, and adsorption capacity decreased when the temperature increased (10-50°C). The equilibrium data fitted very well to the Langmuir model and the extended Langmuir isotherm, for the single and ternary systems, respectively. The maximum adsorption capability was 138.92, 476.31, and 500.13mg/g for LY, SY, and CM, respectively, in a single system and 36.63, 303.31, and 294.12mg/g for LY, SY, and CM, respectively, in a ternary system. The adsorption followed pseudo-second-order kinetics. The thermodynamic parameters indicated that it was a spontaneous and exothermic process. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. A geographically weighted regression model for geothermal potential assessment in mediterranean cultural landscape

    Science.gov (United States)

    D'Arpa, S.; Zaccarelli, N.; Bruno, D. E.; Leucci, G.; Uricchio, V. F.; Zurlini, G.

    2012-04-01

    Geothermal heat can be used directly in many applications (agro-industrial processes, sanitary hot water production, heating/cooling systems, etc.). These applications respond to energetic and environmental sustainability criteria, ensuring substantial energy savings with low environmental impacts. In particular, in Mediterranean cultural landscapes the exploitation of geothermal energy offers a valuable alternative compared to other exploitation systems more land-consuming and visual-impact. However, low enthalpy geothermal energy applications at regional scale, require careful design and planning to fully exploit benefits and reduce drawbacks. We propose a first example of application of a Geographically Weighted Regression (GWR) for the modeling of geothermal potential in the Apulia Region (South Italy) by integrating hydrological (e.g. depth to water table, water speed and temperature), geological-geotechnical (e.g. lithology, thermal conductivity) parameters and land-use indicators. The GWR model can effectively cope with data quality, spatial anisotropy, lack of stationarity and presence of discontinuities in the underlying data maps. The geothermal potential assessment required a good knowledge of the space-time variation of the numerous parameters related to the status of geothermal resource, a contextual analysis of spatial and environmental features, as well as the presence and nature of regulations or infrastructures constraints. We create an ad hoc geodatabase within ArcGIS 10 collecting relevant data and performing a quality assessment. Cross-validation shows high level of consistency of the spatial local models, as well as error maps can depict areas of lower reliability. Based on low enthalpy geothermal potential map created, a first zoning of the study area is proposed, considering four level of possible exploitation. Such zoning is linked and refined by the actual legal constraints acting at regional or province level as enforced by the regional

  7. Potential environmental impacts arising from geopressured-geothermal energy development Texas--Louisiana Gulf Coast region

    Energy Technology Data Exchange (ETDEWEB)

    Gustavson, T.C. (Univ. of Texas, Austin); McGraw, M.M.; Tandy, M.; Parker, F.; Wohlschlag, D.E.; Meriwether, J.

    1977-11-16

    Geopressured-geotheermal resources of the Gulf Coast of Texas and Louisiana are currently being evaluated as thermal-hydraulic energy sources to drive turbines to generate electrical power. Gulf Coast geothermal fluids are brines with salinities generally in excess of 40,000 ppM and tempertures up to 283/sup 0/C (520/sup 0/F). The proportions of dissolved ions in geothermal fluids is markedly different than that of sea water, and the fluids are expected to be saturated with methane. As much as 54,000 m/sup 3/ (310,000 bbls) of fluids per day at a temperature of 049/sup 0/C (300/sup 0/F) will be required to feed one 25 megawatt power plant. The energy resource, the ecological resources of the Gulf Coast, and the potential effects of the development of geothermal energy on ecological resources are described.

  8. Geothermal potential assessment for a low carbon strategy : A new systematic approach applied in southern Italy

    NARCIS (Netherlands)

    Trumpy, E.; Botteghi, S.; Caiozzi, F.; Donato, A.; Gola, G.; Montanari, D.; Pluymaekers, M. P D; Santilano, A.; van Wees, J. D.; Manzella, A.

    2016-01-01

    In this study a new approach to geothermal potential assessment was set up and applied in four regions in southern Italy. Our procedure, VIGORThermoGIS, relies on the volume method of assessment and uses a 3D model of the subsurface to integrate thermal, geological and petro-physical data. The metho

  9. Geothermal potential assessment for a low carbon strategy : A new systematic approach applied in southern Italy

    NARCIS (Netherlands)

    Trumpy, E.; Botteghi, S.; Caiozzi, F.; Donato, A.; Gola, G.; Montanari, D.; Pluymaekers, M. P D; Santilano, A.; van Wees, J. D.; Manzella, A.

    2016-01-01

    In this study a new approach to geothermal potential assessment was set up and applied in four regions in southern Italy. Our procedure, VIGORThermoGIS, relies on the volume method of assessment and uses a 3D model of the subsurface to integrate thermal, geological and petro-physical data. The metho

  10. Geothermal potential assessment for a low carbon strategy: A new systematic approach applied in southern Italy

    NARCIS (Netherlands)

    Trumpy, E.; Botteghi, S.; Caiozzi, F.; Donato, A.; Gola, G.; Montanari, D.; Pluymaekers, M.P.D.; Santilano, A.; Wees, J.D. van; Manzella, A.

    2016-01-01

    In this study a new approach to geothermal potential assessment was set up and applied in four regions in southern Italy. Our procedure, VIGORThermoGIS, relies on the volume method of assessment and uses a 3D model of the subsurface to integrate thermal, geological and petro-physical data. The

  11. Geothermal potential assessment for a low carbon strategy : A new systematic approach applied in southern Italy

    NARCIS (Netherlands)

    Trumpy, E.; Botteghi, S.; Caiozzi, F.; Donato, A.; Gola, G.; Montanari, D.; Pluymaekers, M. P D; Santilano, A.; van Wees, J. D.; Manzella, A.

    2016-01-01

    In this study a new approach to geothermal potential assessment was set up and applied in four regions in southern Italy. Our procedure, VIGORThermoGIS, relies on the volume method of assessment and uses a 3D model of the subsurface to integrate thermal, geological and petro-physical data. The

  12. Effect of ultrasound, low-temperature thermal and alkali pre-treatments on waste activated sludge rheology, hygienization and methane potential.

    Science.gov (United States)

    Ruiz-Hernando, M; Martín-Díaz, J; Labanda, J; Mata-Alvarez, J; Llorens, J; Lucena, F; Astals, S

    2014-09-15

    Waste activated sludge is slower to biodegrade under anaerobic conditions than is primary sludge due to the glycan strands present in microbial cell walls. The use of pre-treatments may help to disrupt cell membranes and improve waste activated sludge biodegradability. In the present study, the effect of ultrasound, low-temperature thermal and alkali pre-treatments on the rheology, hygienization and biodegradability of waste activated sludge was evaluated. The optimum condition of each pre-treatment was selected based on rheological criteria (reduction of steady state viscosity) and hygienization levels (reduction of Escherichia coli, somatic coliphages and spores of sulfite-reducing clostridia). The three pre-treatments were able to reduce the viscosity of the sludge, and this reduction was greater with increasing treatment intensity. However, only the alkali and thermal conditioning allowed the hygienization of the sludge, whereas the ultrasonication did not exhibit any notorious effect on microbial indicators populations. The selected optimum conditions were as follows: 27,000 kJ/kg TS for the ultrasound, 80 °C during 15 min for the thermal and 157 g NaOH/kg TS for the alkali. Afterward, the specific methane production was evaluated through biomethane potential tests at the specified optimum conditions. The alkali pre-treatment exhibited the greatest methane production increase (34%) followed by the ultrasonication (13%), whereas the thermal pre-treatment presented a methane potential similar to the untreated sludge. Finally, an assessment of the different treatment scenarios was conducted considering the results together with an energy balance, which revealed that the ultrasound and alkali treatments entailed higher costs. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Inventory of geothermal resources in Nebraska. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Gosnold, W.D.; Eversoll, D.A.

    1983-06-30

    The goal of the State Coupled Resource Assessment Program is to identify and evaluate geothermal resources in the state, particularly low-temperature potential. Eight tasks were identified and documented in this report as follows: bottom-hole temperature survey, heat flow and temperature gradient survey, data translation studies, gravity data, substate regions, information dissemination, state geothermal map, and reports. The project had three major products: (1) a map, Geothermal Resources of Nebraska; (2) a significant amount of thermal data collected and documented within the state; and (3) a series of publications, presentations and meetings (documented as an Appendix).

  14. Inventory of geothermal resources in Nebraska. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Gosnold, W.D.; Eversoll, D.A.

    1983-06-30

    The goal of the State Coupled Resource Assessment Program is to identify and evaluate geothermal resources in the state, particularly low-temperature potential. Eight tasks were identified and documented in this report as follows: bottom-hole temperature survey, heat flow and temperature gradient survey, data translation studies, gravity data, substate regions, information dissemination, state geothermal map, and reports. The project had three major products: (1) a map, Geothermal Resources of Nebraska; (2) a significant amount of thermal data collected and documented within the state; and (3) a series of publications, presentations and meetings (documented as an Appendix).

  15. Low-Temperature Supercapacitors

    Science.gov (United States)

    Brandon, Erik J.; West, William C.; Smart, Marshall C.

    2008-01-01

    An effort to extend the low-temperature operational limit of supercapacitors is currently underway. At present, commercially available non-aqueous supercapacitors are rated for a minimum operating temperature of -40 C. A capability to operate at lower temperatures would be desirable for delivering power to systems that must operate in outer space or in the Polar Regions on Earth. Supercapacitors (also known as double-layer or electrochemical capacitors) offer a high power density (>1,000 W/kg) and moderate energy density (about 5 to 10 Wh/kg) technology for storing energy and delivering power. This combination of properties enables delivery of large currents for pulsed applications, or alternatively, smaller currents for low duty cycle applications. The mechanism of storage of electric charge in a supercapacitor -- at the electrical double-layer formed at a solid-electrode/liquid-electrolyte interface -- differs from that of a primary or secondary electrochemical cell (i.e., a battery) in such a manner as to impart a long cycle life (typically >10(exp 6) charge/discharge cycles).

  16. GEOTHERMICS GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    <正>20141588 Guo Shiyan(Green Energy Geothermai Development Co.,SINOPEC,Xianyang 712000,China);Li Xiaojun Reservoir Stratum Characteristics and Geothermal Resources Potential of Rongcheng Uplift Geothermal Field in Baoding,Hebei Province(Chinese Journal of Geology,ISSN0563-5020,CN11-1937/P,48(3),2013,p.922-931,2 illus.,4 tables,10 refs.)Key words:geothermal fields,Hebei Province

  17. Replacing critical radiators to increase the potential to use low-temperature district heating – A case study of 4 Danish single-family houses from the 1930s

    DEFF Research Database (Denmark)

    Østergaard, Dorte Skaarup; Svendsen, Svend

    2016-01-01

    radiator sizes and heating demands in 4 existing Danish single-family houses from the 1930s. A year-long dynamic simulation was performed for each of the houses to evaluate the potential to lower the heating system temperatures. The results indicate that there is a large potential to use low-temperature...... district heating in existing single-family houses. In order to obtain the full potential of low-temperature district heating, critical radiators must be replaced. Based on a novel method, a total of nine radiators were identified to be critical to ensure thermal comfort and low return temperatures in two......Low-temperature district heating is a promising technology for providing homes with energy-efficient heating in the future. However, it is of great importance to maintain thermal comfort in existing buildings when district heating temperatures are lowered. This case study evaluated the actual...

  18. Potential decline in geothermal energy generation due to rising temperatures under climate change scenarios

    Science.gov (United States)

    Angel, E.; Ortega, S.; Gonzalez-Duque, D.; Ruiz-Carrascal, D.

    2016-12-01

    Geothermal energy production depends on the difference between air temperature and the geothermal fluid temperature. The latter remains approximately constant over time, so the power generation varies according to local atmospheric conditions. Projected changes in near-surface air temperatures in the upper levels of the tropical belt are likely to exceed the projected temperature anomalies across many other latitudes, which implies that geothermal plants located in these regions may be affected, reducing their energy output. This study focuses on a hypothetical geothermal power plant, located in the headwaters of the Claro River watershed, a key high-altitude basin in Los Nevados Natural Park, on the El Ruiz-Tolima volcanic massif, in the Colombian Central Andes, a region with a known geothermal potential. Four different Atmospheric General Circulation Models where used to project temperature anomalies for the 2040-2069 prospective period. Their simulation outputs were merged in a differentially-weighted multi-model ensemble, whose weighting factors were defined according to the capability of individual models to reproduce ground truth data from a set of digital data-loggers installed in the basin since 2008 and from weather stations gathering climatic variables since the early 50s. Projected anomalies were computed for each of the Representative Concentration Pathways defined by the IPCC Fifth Assessment Report in the studied region. These climate change projections indicate that air temperatures will likely reach positive anomalies in the range +1.27 ºC to +3.47 ºC, with a mean value of +2.18 ºC. Under these conditions, the annual energy output declines roughly 1% per each degree of increase in near-surface temperature. These results must be taken into account in geothermal project evaluations in the region.

  19. Geology and geothermal potential of the tecuamburro volcano area, Guatemala

    Science.gov (United States)

    Duffield, W.A.; Heiken, G.H.; Wohletz, K.H.; Maassen, L.W.; Dengo, G.; McKee, E.H.; Castaneda, O.

    1992-01-01

    Tecuamburro, an andesitic stratovolcano in southeastern Guatemala, is within the chain of active volcanoes of Central America. Though Tecuamburro has no record of historic eruptions, radiocarbon ages indicate that eruption of this and three other adjacent volcanoes occurred within the past 38,300 years. The youngest eruption produced a dacite dome. Moreover, powerful steam explosions formed a 250 m wide crater about 2900 years ago near the base of this dome. The phreatic crater contains a pH-3 thermal lake. Fumaroles are common along the lake shore, and several other fumaroles are located nearby. Neutral-chloride hot springs are at lower elevations a few kilometers away. All thermal manifestations are within an area of about 400 km2 roughly centered on Tecuamburro Volcano. Thermal implications of the volume, age, and composition of the post-38.3 ka volcanic rocks suggest that magma, or recently solidified hot plutons, or both are in the crust beneath these lavas. Chemical geothermometry carried out by other workers suggests that a hydrothermal-convection system is centered over this crustal heat source. Maximum temperatures of about 300??C are calculated for samples collected in the area of youngest volcanism, whereas samples from outlying thermal manifestations yield calculated temperatures <- 165??C. An 808 m deep drill hole completed in 1990 to partly test the geothermal model developed from surface studies attained a maximum temperature of almost 240??C. Thus, the possibility of a commercial-grade hydrothermal resource in the area seems high. ?? 1992.

  20. Relationshipe Between Self-potential Anomalies and Hydraulic Flow In A Geothermal System: Application To Cerro-prieto, Baja California

    Science.gov (United States)

    Saracco, G.; Revil, A.; Pessel, M.

    The Cerro Prieto geothermal field is located in the alluvial plain of the Mexicali Valley, northern Baja California, Mexico, at about 35 km southeast of the city of Mexicali. The Cerro Prieto geothermal field is one of several high temperature water-dominated geothermal fields within the Salton Trough. We analyze here the self-potential distri- bution at the ground surface in order to determine the pattern of fluid flow in te sub- surface of this geothermal field. Various methods of analysis of self-potential anoma- lies are employed to reach this purpose. We use density probability tomography of monopolar and dipolar electrical sources and an Euler-type analysis. The hydraulic flow pattern found in this geothermal field is in agreement with that detemined from the heat flux inside the structure.

  1. Elastic collisions between Si and D atoms at low temperatures and accurate analytic potential energy function and molecular constants of the SiD(X2∏) radical

    Institute of Scientific and Technical Information of China (English)

    Shi De-Heng; Zhang Jin-Ping; Sun Jin-Feng; Zhu Zun-Lue

    2009-01-01

    Interaction potential of the SiD(X2∏) radical is constructed by using the CCSD(T) theory in combination with the largest correlation-consistent quintuple basis set augmented with the diffuse functions in the valence range. Using the interaction potential, the spectroscopic parameters are accurately determined. The present D0, De, Re, ωe, αe and Be values are of 3.0956 eV, 3.1863 eV, 0.15223 nm, 1472.894 cm-1, 0.07799 cm-1 and 3.8717 cm-1, respectively,which are in excellent agreement with the measurements. A total of 26 vibrational states is predicted when J = 0 by solving the radial Schr(o)dinger equation of nuclear motion. The complete vibrational levels, classical turning points,initial rotation and centrifugal distortion constants when J = 0 are reported for the first time, which are in good accord with the available experiments. The total and various partial-wave cross sections are calculated for the elastic collisions between Si and D atoms in their ground states at 1.0×10-11-1.0×10-3 a.u. when the two atoms approach each other along the SiD(X2∏) potential energy curve. Four shape resonances are found in the total elastic cross sections, and their resonant energies are of 1.73×10-5, 4.0×10-5, 6.45×10-5 and 5.5×10-4 a.u., respectively. Each shape resonance in the total elastic cross sections is carefully investigated. The results show that the shape of the total elastic cross sections is mainly dominated by the s partial wave at very low temperatures. Because of the weakness of the shape resonances coming from the higher partial waves, most of them are passed into oblivion by the strong s partial-wave elastic cross sections.

  2. Geothermal Potential Evaluation for Northern Chile and Suggestions for New Energy Plans

    Directory of Open Access Journals (Sweden)

    Monia Procesi

    2014-08-01

    Full Text Available Chile is a country rich in natural resources, and it is the world’s largest producer and exporter of copper. Mining is the main industry and is an essential part of the Chilean economy, but the country has limited indigenous fossil fuels—over 90% of the country’s fossil fuels must be imported. The electricity market in Chile comprises two main independent systems: the Northern Interconnected Power Grid (SING and the Central Interconnected Power Grid (SIC. Currently, the primary Chilean energy source is imported fossil fuels, whereas hydropower represents the main indigenous source. Other renewables such as wind, solar, biomass and geothermics are as yet poorly developed. Specifically, geothermal energy has not been exploited in Chile, but among all renewables it has the greatest potential. The transition from thermal power plants to renewable energy power plants is an important target for the Chilean Government in order to reduce dependence on imported fossil fuels. In this framework, the proposed study presents an evaluation of the geothermal potential for northern Chile in terms of power generation. The El Tatio, Surire, Puchuldiza, Orriputunco-Olca and Apacheta geothermal fields are considered for the analysis. The estimated electrical power is approximately 1300 MWe, and the energy supply is 10,200 GWh/year. This means that more than 30% of the SING energy could be provided from geothermal energy, reducing the dependence on imported fossil fuels, saving 8 Mton/year of CO2 and supplying the mining industry, which is Chile’s primary energy user.

  3. The geothermal energy potential in Denmark - updating the database and new structural and thermal models

    Science.gov (United States)

    Nielsen, Lars Henrik; Sparre Andersen, Morten; Balling, Niels; Boldreel, Lars Ole; Fuchs, Sven; Leth Hjuler, Morten; Kristensen, Lars; Mathiesen, Anders; Olivarius, Mette; Weibel, Rikke

    2017-04-01

    Knowledge of structural, hydraulic and thermal conditions of the subsurface is fundamental for the planning and use of hydrothermal energy. In the framework of a project under the Danish Research program 'Sustainable Energy and Environment' funded by the 'Danish Agency for Science, Technology and Innovation', fundamental geological and geophysical information of importance for the utilization of geothermal energy in Denmark was compiled, analyzed and re-interpreted. A 3D geological model was constructed and used as structural basis for the development of a national subsurface temperature model. In that frame, all available reflection seismic data were interpreted, quality controlled and integrated to improve the regional structural understanding. The analyses and interpretation of available relevant data (i.e. old and new seismic profiles, core and well-log data, literature data) and a new time-depth conversion allowed a consistent correlation of seismic surfaces for whole Denmark and across tectonic features. On this basis, new topologically consistent depth and thickness maps for 16 geological units from the top pre-Zechstein to the surface were drawn. A new 3D structural geological model was developed with special emphasis on potential geothermal reservoirs. The interpretation of petrophysical data (core data and well-logs) allows to evaluate the hydraulic and thermal properties of potential geothermal reservoirs and to develop a parameterized numerical 3D conductive subsurface temperature model. Reservoir properties and quality were estimated by integrating petrography and diagenesis studies with porosity-permeability data. Detailed interpretation of the reservoir quality of the geological formations was made by estimating net reservoir sandstone thickness based on well-log analysis, determination of mineralogy including sediment provenance analysis, and burial history data. New local surface heat-flow values (range: 64-84 mW/m2) were determined for the Danish

  4. Geothermal direct heat use: Market potential/penetration analysis for Federal Region 9

    Science.gov (United States)

    Powell, W. (Editor); Tang, K. (Editor)

    1980-01-01

    A preliminary study was made of the potential for geothermal direct heat use in Arizona, California, Hawaii, and Nevada (Federal Region 9). An analysis was made of each state to: (1) define the resource, based on the latest available data; (2) assess the potential market growth for geothermal energy; and (3) estimate the market penetration, projected to 2020. Findings of the study include the following: (1) Potentially economical hydrothermal resources exist in all four states of the Region: however, the resource data base is largely incomplete, particularly for low to moderate temperature resources. (2) In terms of beneficial heat, the total hydrothermal resource identified so far for the four states is on the order of 43 Quads, including an estimated 34 Quads of high temperature resources which are suitable for direct as well as electrical applications. (3) In California, Hawaii, and Nevada, the industrial market sector has somewhat greater potential for penetration than the residential/commercial sector. In Arizona, however, the situation is reversed, due to the collocation of two major metropolitan areas (Phoenix and Tucson) with potential geothermal resources.

  5. Geothermal energy utilisation in Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Grepmeier, K. [Zentrum fuer rationelle Energieanwendung und Umwelt GmbH (ZREU), Regensburg (Germany)

    2005-04-01

    The following article highlights some of the outcomes derived from a survey which has been conducted by an international consortium under the auspices of the German consultancy Zentrum fuer rationelle Energieanwendung und Umwelt GmbH (ZREU) in the frame of a cooperative action entitled 'Promotion of Geothermal Energy Utilisation in Turkey'. The project which has been carried out under the umbrella of the European Union's Framework Programme for Research and Technological Development also featured a European business forum and technical site visit about 'Geothermal Energy Opportunities in Turkey' and a site visit tour to successful European geothermal utilisation schemes aiming to foster exchange of experience and to initiate business contacts between Turkish and European market actors. Special consideration has been given to investigate the potential of geothermal electricity generation with future-oriented binary cycle processes (e.g. based on Kalina technology) specifically suitable to exploit Turkey's low temperature geothermal reservoirs. Following up the activities ZREU has entered into a co-operation scheme with e.terras AG and leading technology providers to develop high efficient European turn-key solutions for promising goethermal markets worldwide. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

    Clark, C. E. [Argonne National Lab. (ANL), Argonne, IL (United States); Harto, C. B. [Argonne National Lab. (ANL), Argonne, IL (United States); Troppe, W. A. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2011-09-01

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

  7. Modeling low-temperature serpentinization reactions to estimate molecular hydrogen production with implications for potential microbial life on Saturn's moon Enceladus.

    Science.gov (United States)

    Zwicker, Jennifer; Smrzka, Daniel; Taubner, Ruth-Sophie; Bach, Wolfgang; Rittmann, Simon; Schleper, Christa; Peckmann, Jörn

    2017-04-01

    Serpentinization of ultramafic rocks attracts much interest in research on the origin of life on Earth and the search for life on extraterrestrial bodies including icy moons like Enceladus. Serpentinization on Earth occurs in peridotite-hosted systems at slow-spreading mid-ocean ridges, and produces large amounts of molecular hydrogen and methane. These reduced compounds can be utilized by diverse chemosynthetic microbial consortia as a metabolic energy source. Although many hydrothermal vents emit hot and acidic fluids today, it is more likely that life originated in the Archean at sites producing much cooler and more alkaline fluids that allowed for the synthesis and stability of essential organic molecules necessary for life. Therefore, a detailed understanding of water-rock interaction processes during low-temperature serpentinization is of crucial importance in assessing the life-sustaining potential of these environments. In the course of serpentinization, the metasomatic hydration of olivine and pyroxene produces various minerals including serpentine minerals, magnetite, brucite, and carbonates. Hydrogen production only occurs if ferrous iron within iron-bearing minerals is oxidized and incorporated as ferric iron into magnetite. The PHREEQC code was used to model the pH- and temperature-dependent dissolution of olivine and pyroxene to form serpentine, magnetite and hydrogen under pressure and temperature conditions that may exist on Saturn's icy moon Enceladus. Various model setups at 25 and 50°C were run to assess the influence of environmental parameters on hydrogen production. The results reveal that hydrogen production rates depend on the composition of the initial mineral assemblage and temperature. The current assumption is that there is a gaseous phase between Enceladus' ice sheet and subsurface ocean. To test various scenarios, model runs were conducted with and without the presence of a gas phase. The model results show that hydrogen production is

  8. Potential for a significant deep basin geothermal system in Tintic Valley, Utah

    Science.gov (United States)

    Hardwick, C.; Kirby, S.

    2014-12-01

    The combination of regionally high heat flow, deep basins, and permeable reservoir rocks in the eastern Great Basin may yield substantial new geothermal resources. We explore a deep sedimentary basin geothermal prospect beneath Tintic Valley in central Utah using new 2D and 3D models coupled with existing estimates of heat flow, geothermometry, and shallow hydrologic data. Tintic Valley is a sediment-filled basin bounded to the east and west by bedrock mountain ranges where heat-flow values vary from 85 to over 240 mW/m2. Based on modeling of new and existing gravity data, a prominent 30 mGal low indicates basin fill thickness may exceed 2 km. The insulating effect of relatively low thermal conductivity basin fill in Tintic Valley, combined with typical Great Basin heat flow, predict temperatures greater than 150 °C at 3 km depth. The potential reservoir beneath the basin fill is comprised of Paleozoic carbonate and clastic rocks. The hydrology of the Tintic Valley is characterized by a shallow, cool groundwater system that recharges along the upper reaches of the basin and discharges along the valley axis and to a series of wells. The east mountain block is warm and dry, with groundwater levels just above the basin floor and temperatures >50 °C at depth. The west mountain block contains a shallow, cool meteoric groundwater system. Fluid temperatures over 50 °C are sufficient for direct-use applications, such as greenhouses and aquaculture, while temperatures exceeding 140°C are suitable for binary geothermal power plants. The geologic setting and regionally high heat flow in Tintic Valley suggest a geothermal resource capable of supporting direct-use geothermal applications and binary power production could be present.

  9. UWC geothermal resource exploration

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-04-01

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

  10. Geothermic Potential Assessment of hydrothermal vents of Township Barranca De Upia - Meta - Colombia

    Science.gov (United States)

    Chica, J.; Chicangana, G.; Eco Energy Research Group

    2013-05-01

    Hydrothermal vents have been traditionally exploited in Colombia as a source of tourism revenue such as pools and saunas. Leaving aside its high potential for geothermal power generation in applications like heating, drying, cooling, extensive use in crops, livestock, electricity generation and more. Currently the use given to this natural resource in the town of Barranca de Upia in Meta department, central Colombia, is like Wellness Centre. However, the geothermal gradient for the area where hydrothermal vents occur, indicates that the water emerges at temperatures above 70 ° C (Alfaro et al., 2003), which opens a window of opportunity to assess their geothermal potential, in order to know the actual energy potential of the region as an option of augmenting their development. this research is the analysis of information gathered from databases in gravimetry and magnetometry of the study area and the temperatures measured in wells derived from the oil industry. Based on that information, a numerical analysis of the data will be performed in order to establish a model to parameterize the energy potential of the study area and identify possible uses of the energy contained by the hydrothermal vents.

  11. Spectroscopy of Low Temperature Plasma

    CERN Document Server

    Ochkin, Vladimir N

    2009-01-01

    Providing an up-to-date overview on spectroscopical diagnostics of low temperature plasma Spectroscopy of Low Temperature Plasma covers the latest developments and techniques. Written by a distinguished scientist and experienced book author this text is applicable to many fields in materials and surface science as well as nanotechnology and contains numerous appendices with indispensable reference data.

  12. Geothermal energy development in Washington State. A guide to the federal, state and local regulatory process

    Energy Technology Data Exchange (ETDEWEB)

    Bloomquist, R.G.; Simpson, S.J.

    1986-03-01

    Washington State's geothermal potential is wide spread. Hot springs and five strato volcanoes existing throughout the Cascade Range, limited hot spring activity on the Olympic Peninsula, and broad reaching, low temperature geothermal resources found in the Columbia Basin comprise the extent of Washington's known geothermal resources. Determination of resource ownership is the first step in proceeding with geothermal exploration and development activities. The federal and state processes are examined from pre-lease activity through leasing and post-lease development concerns. Plans, permits, licenses, and other requirements are addressed for the federal, state, and local level. Lease, permit, and other forms for a number of geothermal exploration and development activities are included. A map of public lands and another displaying the measured geothermal resources throughout the state are provided.

  13. Using hydrogeologic data to evaluate geothermal potential in the eastern Great Basin

    Science.gov (United States)

    Masbruch, Melissa D.; Heilweil, Victor M.; Brooks, Lynette E.

    2012-01-01

    In support of a larger study to evaluate geothermal resource development of high-permeability stratigraphic units in sedimentary basins, this paper integrates groundwater and thermal data to evaluate heat and fluid flow within the eastern Great Basin. Previously published information from a hydrogeologic framework, a potentiometric-surface map, and groundwater budgets was compared to a surficial heat-flow map. Comparisons between regional groundwater flow patterns and surficial heat flow indicate a strong spatial relation between regional groundwater movement and surficial heat distribution. Combining aquifer geometry and heat-flow maps, a selected group of subareas within the eastern Great Basin are identified that have high surficial heat flow and are underlain by a sequence of thick basin-fill deposits and permeable carbonate aquifers. These regions may have potential for future geothermal resources development.

  14. THE ECONOMIC IMPLICATIONS OF THE GEOTHERMAL POTENTIAL OF WEST AND NORTHWEST REGION OF ROMANIA

    Directory of Open Access Journals (Sweden)

    Perticas Razvan

    2010-12-01

    Full Text Available The energy crises of the 70s led to the vigorous interventions of the industrialized states in the energy sector. On the European political agenda a new problem appeared, namely the one regarding the security of the energy supply. Romania is the third geothermal power in Europe, after Italy and Greece. The energy potential produced by means of geothermal resources of the West and North - West regions is approximately of 144 MWt. The production of a MWt of electricity through conventional sources (in our case study we chose diesel emits into the atmosphere about 21,673 tons of CO2. If it’s used the entire installed capacity in these areas Romania reduces pollution by approximately 6,935,552 TCO2.

  15. Geothermal Potential of the Cascade and Aleutian Arcs, with Ranking of Individual Volcanic Centers for their Potential to Host Electricity-Grade Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Shevenell, Lisa [ATLAS Geosciences, Inc., Reno, NV (United States); Coolbaugh, Mark [ATLAS Geosciences, Inc., Reno, NV (United States); Hinz, Nick [Univ. of Nevada, Reno, NV (United States); Stelling, Pete [Western Washington Univ., Bellingham, WA (United States); Melosh, Glenn [GEODE, Santa Rosa, CA (United States); Cumming, William [Cumming Geoscience, Santa Rosa, CA (United States)

    2015-10-16

    This project brings a global perspective to volcanic arc geothermal play fairway analysis by developing statistics for the occurrence of geothermal reservoirs and their geoscience context worldwide in order to rank U.S. prospects. The focus of the work was to develop play fairways for the Cascade and Aleutian arcs to rank the individual volcanic centers in these arcs by their potential to host electricity grade geothermal systems. The Fairway models were developed by describing key geologic factors expected to be indicative of productive geothermal systems in a global training set, which includes 74 volcanic centers world-wide with current power production. To our knowledge, this is the most robust geothermal benchmark training set for magmatic systems to date that will be made public.

  16. Efficient low-temperature thermophotovoltaic emitters from metallic photonic crystals.

    Science.gov (United States)

    Nagpal, Prashant; Han, Sang Eon; Stein, Andreas; Norris, David J

    2008-10-01

    We examine the use of metallic photonic crystals as thermophotovoltaic emitters. We coat silica woodpile structures, created using direct laser writing, with tungsten or molybdenum. Optical reflectivity and thermal emission measurements near 650 degrees C demonstrate that the resulting structures should provide efficient emitters at relatively low temperatures. When matched to InGaAsSb photocells, our structures should generate over ten times more power than solid emitters while having an optical-to-electrical conversion efficiency above 32%. At such low temperatures, these emitters have promise not only in solar energy but also in harnessing geothermal and industrial waste heat.

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

    Energy Technology Data Exchange (ETDEWEB)

    East, J.

    1981-05-01

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

  18. Geothermal potential on Kirtland Air Force Base lands, Bernalillo County, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Grant, P.R. Jr.

    1981-10-01

    Extensive sampling and geochemical analysis of groundwater in and near the base disclosed no significant geothermal parameters. However, structural conditions and current hydrologic regimes strongly suggest that thermal waters would be masked by near surface, low temperature meteoric water originating as rain and snowfall in the nearby mountains. Controlled source audio-magnetotelluric (CSAMT) electromagnetic techniques, refraction seismic experiments, and gravity traverses were utilized on the base. These, together with published geohysical information that presents evidence for a shallow magma body beneath the Albuquerque Basin; favorable terrestrial heat flow, water chemistry, and shallow temperature gradient holes on the nearby mesa west of the Rio Grande; interpretation of regional gravity data; and geological data from nearby deep wells tend to confirm structural, stratigraphic, and hydrologic conditions favorable for developing an extensive intermediate to high-temperature hydrothermal regime on portions of Kirtland AFB lands where intensive land use occurs. Two possible exploration and development scenarios are presented. One involves drilling a well to a depth of 3000 to 5000 ft (914 to 1524 m) to test the possibility of encountering higher than normal water temperatures on the basinward side of the faults underlying the travertine deposits. The other is to conduct limited reflection seismograph surveys in defined areas on the base to determine the depth to basement (granite) and thickness of the overyling, unconfined, water filled, relatively unconsolidated sand and gravel aquifer.

  19. Analysis of deep geothermal potential in the free State of Saxony; Analyse des tiefengeothermischen Potenzials im Freistaat Sachsen

    Energy Technology Data Exchange (ETDEWEB)

    Boeck, H.-J.; Lange, T. [C und E Analytik- und Umweltdienstleistungs GmbH, Chemnitz (Germany); Tunger, B.; Schneider, P. [C und E Consulting und Engineering GmbH, Chemnitz (Germany); Grafe, F.; Wilsnack, T. [IBeWa-Ingenieurpartnerschaft fuer Bergbau, Wasser- und Deponietechnik, Freiberg/Sachsen (Germany)

    2007-07-15

    This illustrated article takes a look at the potential for the use of deep geothermal heat in the Free State of Saxony in Germany. Based on the entry of existing deep geothermal borehole data and their processing in a geo-database, the potential for the use of deep geothermal heat was re-evaluated. The purpose of the project, to create an up-to-date and practicable basis for middle-term deep geothermal projects, is discussed. A model-based prognosis of temperatures was obtained by processing all data recorded in the database. The assessment of the technical potential of geothermal use was performed for deep bore-hole heat exchangers (BHE) using computer-based simulation of the performance of deep BHEs with respect to generating heat and electric power. The perspectives for geothermal use in Saxony are discussed in consideration of the results of the simulations and initial estimates for other kinds of heat extraction technologies. The methods and the concept of the model used are discussed and the results obtained are presented in tabular and graphical form. Economic factors and future prospects are also examined.

  20. Investigation of the 1D symmetrical linear graded superconductor-dielectric photonic crystals and its potential applications as an optimized low temperature sensors

    Science.gov (United States)

    Baraket, Zina; Zaghdoudi, Jihene; Kanzari, Mounir

    2017-02-01

    Based on the Transfer Matrix Method (TMM) and the two fluid model for a superconductor and by taking account of the thermal expansion effect and thermo optical effects, we theoretically investigates the transmittance spectra of a one dimensional superconductor -dielectric photonic crystal (PC) designed as ((HLS)5/(SLH)5) made up of a BiGeO12(H), SiO2(L) and YaBO2CuO7 (S). The transmittance spectra shows that the system realizes a tunable filter which depends on a nonlinear relation with temperature. It's found that the symmetrical application of a linear deformation d(m) = d0+(m-1).δd(m) where d0 is the initial thickness of the layer m, δd(m) is the elementary added thickness at each layer. This linear gradation of the thickness permits to improve the temperature sensitivity of the system which acts as an optimized low temperature sensor.

  1. Analysis of potential migrants from plastic materials in milk by liquid chromatography-mass spectrometry with liquid-liquid extraction and low-temperature purification.

    Science.gov (United States)

    Bodai, Zsolt; Szabó, Bálint Sámuel; Novák, Márton; Hámori, Susanne; Nyiri, Zoltán; Rikker, Tamás; Eke, Zsuzsanna

    2014-10-15

    A simple and fast analytical method was developed for the determination of six UV stabilizers (Cyasorb UV-1164, Tinuvin P, Tinuvin 234, Tinuvin 326, Tinuvin 327, and Tinuvin 1577) and five antioxidants (Irgafos 168, Irganox 1010, Irganox 3114, Irganox 3790, and Irganox 565) in milk. For sample preparation liquid-liquid extraction with low-temperature purification combined with centrifugation was used to remove fats, proteins, and sugars. After the cleanup step, the sample was analyzed with high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS). External standard and matrix calibrations were tested. External calibration proved to be acceptable for Tinuvin P, Tinuvin 234, Tinuvin 326, Tinuvin 327, Irganox 3114, and Irganox 3790. The method was successfully validated with matrix calibration for all compounds. Method detection limits were between 0.25 and 10 μg/kg. Accuracies ranged from 93 to 109%, and intraday precisions were <13%.

  2. Geothermal assessment of the lower Bear River drainage and northern East Shore ground-water areas, Box Elder County, Utah

    Energy Technology Data Exchange (ETDEWEB)

    Klauk, R.H.; Budding, K.E.

    1984-07-01

    The Utah Geological and Mineral Survey (UGMS) has been researching the low-temperature geothermal resource potential in Utah. This report, part of an area-wide geothermal research program along the Wasatch Front, concerns the study conducted in the lower Bear River drainage and northern East Shore ground-water areas in Box Elder County, Utah. The primary purpose of the study is to identify new areas of geothermal resource potential. There are seven known low-temperature geothermal areas in this part of Box Elder County. Geothermal reconnaissance techniques used in the study include a temperature survey, chemical analysis of well and spring waters, and temperature-depth measurements in accessible wells. The geothermal reconnaissance techniques identified three areas which need further evaluation of their low-temperature geothermal resource potential. Area 1 is located in the area surrounding Little Mountain, area 2 is west and southwest of Plymouth, and area 3 is west and south of the Cutler Dam. 5 figures, 4 tables.

  3. Sensors for low temperature application

    Science.gov (United States)

    Henderson, Timothy M.; Wuttke, Gilbert H.

    1977-01-01

    A method and apparatus for low temperature sensing which uses gas filled micro-size hollow glass spheres that are exposed in a confined observation area to a low temperature range (Kelvin) and observed microscopically to determine change of state, i.e., change from gaseous state of the contained gas to condensed state. By suitable indicia and classification of the spheres in the observation area, the temperature can be determined very accurately.

  4. Low temperature relations in QCD

    CERN Document Server

    Agasian, N O

    2002-01-01

    In this talk I discuss the low temperature relations for the trace of the energy-momentum tensor in QCD with two and three quarks. It is shown that the temperature derivatives of the anomalous and normal (quark massive term) contributions to the trace of the energy-momentum tensor in QCD are equal to each other in the low temperature region. Leading corrections connected with $\\pi\\pi$-interactions and thermal excitations of $K$ and $\\eta$ mesons are calculated.

  5. Warm water geothermal and cold energy in western Canada

    Energy Technology Data Exchange (ETDEWEB)

    Peachey, B. [New Paradigm Engineering Ltd., Edmonton, AB (Canada)]|[Petroleum Technology Alliance Canada, Calgary, AB (Canada)

    2007-07-01

    The Petroleum Technology Alliance of Canada's low carbon futures study was discussed along with a study in which scenarios were developed for three resources, notably bitumen in carbonate reservoirs; conventional heavy oil; and warm water geothermal energy from operating oil wells. The presentation provided an overview of geothermal systems including hot dry rock; dry steam resources; hot water resources; warm water resources; and low temperature systems. A warm water geothermal study for the Western Canada Sedimentary Basin (WCSB) was also presented. Although high quality geothermal energy sources are rare in Canada, there are large warm water geothermal reservoirs, ranging in temperature from 50 to 180 degrees C in the WCSB. This presentation focused on the potential for recovery of the warm water geothermal energy already being brought to surface from the WCSB's oil wells. Several energy approaches were also presented, such as warm geothermal or produced water being used for heating an oil reservoir; using produced mechanical energy for field pumping; and producing renewable electricity from binary plants with propane. Illustrations were also provided for the organic Rankine cycle; low pump geothermal power; and no pump geothermal system. Combined geothermal and oil production were also discussed. Other topics that were presented included industrial cooling; municipal cooling; mined oilsands barriers and tailings; containment of in-situ oilsands; and rural freeze desalination. The report concluded with discussions of the Canadian minerals industry; cold Arctic construction; and ice roads in the North. It was concluded that there is potential for warm water geothermal in existing oilfield operations in Canada. tabs., figs.

  6. G.POT: a method for the assessment and mapping of the near-surface geothermal potential

    Science.gov (United States)

    Casasso, Alessandro; Sethi, Rajandrea

    2017-04-01

    Shallow geothermal systems are widely recognised as a valuable technology for the heating and cooling of buildings. The most adopted technology is the Borehole Heat Exchanger (BHE), since it can be installed almost everywhere. However, the economic viability of BHEs depends on the thermal load that can be efficiently exchanged with the ground, i.e. the near-surface geothermal potential. We present the G.POT (Geothermal POTential) method for the assessment of near-surface geothermal potential as a function of the thermal conductivity and capacity of the ground, of its initial temperature, of the thermal resistance of the BHE and of the duration of the sinusoidal thermal load cycle, which reproduces the typical pattern of a thermal load during a heating or a cooling season. The function was calibrated from the results of numerical heat transfer simulations, performed varying the values of the aforementioned parameters over broad ranges. G.POT is a simple mathematical tool which can be easily implemented for the large-scale assessment and mapping of the near-surface geothermal potential for heating or cooling purpose. An example of its application is also shown, and advice is provided on the processing of input parameters. References A. Casasso, R. Sethi, G.POT: A quantitative method for the assessment and mapping of the shallow geothermal potential, Energy 106 (2016) 765-773. A. Casasso, R. Sethi, Assessment and mapping of the shallow geothermal potential in the province of Cuneo (Piedmont, NW Italy), Renewable Energy 102, Part B (2017) 306-315.

  7. Improving geothermal power plants with a binary cycle

    Science.gov (United States)

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

    2015-12-01

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

  8. Processing of thermal parameters for the assessment of geothermal potential of sedimentary basins

    Science.gov (United States)

    Pasquale, V.; Chiozzi, P.; Gola, G.; Verdoya, M.

    2009-04-01

    The growing interest on renewable energy sources is stimulating new efforts aimed at the assessment of geothermal potential in several countries, and new developments are expected in the near future. In this framework, a basic step forward is to focus geothermal investigations on geological environments which so far have been relatively neglected. Some intracontinental sedimentary basins could reveal important low enthalpy resources. The evaluation of the geothermal potential in such geological contexts involves the synergic use of geophysical and hydrogeological methodologies. In sedimentary basins a large amount of thermal and hydraulic data is generally available from petroleum wells. Unfortunately, borehole temperature data are often affected by a number of perturbations which make very difficult determination of the true geothermal gradient. In this paper we addressed the importance of the acquisition of thermal parameters (temperature, geothermal gradient, thermal properties of the rock) and the technical processing which is necessary to obtain reliable geothermal characterizations. In particular, techniques for corrections of bottom-hole temperature (BHT) data were reviewed. The objective was to create a working formula usable for computing the undisturbed formation temperature for specific sedimentary basins. As test areas, we analysed the sedimentary basins of northern Italy. Two classical techniques for processing temperature data from oil wells are customarily used: (i) the method by Horner, that requires two or more measurements of bottom-hole temperatures carried out at the same depth but at different shut-in times te and (ii) the technique by Cooper and Jones, in which several physical parameters of the mud and formation need to be known. We applied both methods to data from a number of petroleum explorative wells located in two areas of the Po Plain (Apenninic buried arc and South Piedmont Basin - Pedealpine homocline). From a set of about 40 wells

  9. Near-surface geothermal potential assessment of the region Leogang - Saalbach-Hinterglemm in Salzburg, Austria

    Science.gov (United States)

    Bottig, Magdalena; Rupprecht, Doris; Hoyer, Stefan

    2017-04-01

    Within the EU-funded Alpine Space project GRETA (Near-surface Geothermal Resources in the Territory of the Alpine space), a potential assessment for the use of near-surface geothermal energy is being performed. The focus region for Austria is represented by the two communities Leogang and Saalbach-Hinterglemm where settlements are located in altitudes of about 800 - 1.000 m. In these communities, as well as in large parts of the alpine space region in Austria, winter sports tourism is an important economic factor. The demand for heating and domestic hot water in this region of about 6.000 inhabitants rises significantly in the winter months due to around 2 million guest nights per year. This makes clear why the focus is on touristic infrastructure like alpine huts or hotels. It is a high-altitude area with a large number of remote houses, thus district-heating is not ubiquitous - thus, near-surface geothermal energy can be a useful solution for a self-sufficient energy supply. The objective of detailed investigation within the project is, to which extent the elevation, the gradient and the orientation of the hillside influence the geothermal usability of the shallow underground. To predict temperatures in depths of up to 100 m and therefore make statements on the geothermal usability of a certain piece of land, it is necessary to attain a precise ground-temperature map which reflects the upper model boundary. As there are no ground temperature measurement stations within the region, the GBA has installed four monitoring stations. Two are located in the valley, at altitudes of about 800 m, and two in higher altitudes of about 1.200 m, one on a south- and one on a north-slope. Using a software invented by the University of Soil Sciences in Vienna a ground-temperature map will be calculated. The calculation is based on climatic data considering parameters like soil composition. Measured values from the installed monitoring stations will help to validate or to

  10. Mapping the geothermal potential of fault zones in the sedimentary basins of the Belgian and Netherlands border region.

    Science.gov (United States)

    Loveless, Sian; Pluymaekers, Maarten; Lagrou, David; Laenen, Ben; Doornenbal, Hans; De Boever, Eva

    2014-05-01

    Faults often determine the success or failure of low enthalpy geothermal projects. This is due to their prevalence throughout the subsurface and capacity to behave as significant fluid flow pathways or baffles (or both simultaneously). Here we present the methodology and results of an assessment of the capacity of faults in the Belgium and Netherlands border region to impact geothermal potential. This work was completed as part of a crossborder project in the European INTERREG Iva program Flanders-The Netherlands. The geothermal potential of reservoirs and fault zones was mapped across the Belgian provinces of Limburg and Antwerpen, and Dutch provinces of Limburg and Noord-Brabant. The Roer Valley Graben (RVG) and the Campine Basin are the main structural elements within this region. The four most significant reservoir intervals were correlated across the border. These comprise Upper Cretaceous chalk, Lower Triassic sandstones, Upper Carboniferous sandstones and Lower Carboniferous limestones. Mapped faults cutting these intervals were also correlated. Regional-scale maps have been created indicating the likelihood of fault zones to improve geothermal potential in these intervals. The capacity of faults to improve geothermal potential was determined from factors known to increase or decrease fault permeability. Lithology was a primary consideration: Carbonate rocks tend to fracture along fault zones, creating breccia or joints, resulting in an increased permeability. Permeability can be further increased by karst processes, as evidenced at the Venlo geothermal project, Netherlands. Therefore areas with faults in the carbonate reservoirs were considered to have possible potential. Conversely, permeability is likely to decrease in the clastic reservoir units as cataclastic processes dominate. Such faults were not considered to have additional geothermal potential. The timing of fault activity was considered another key variable. Recently deformed faults are more

  11. IRETHERM: Research and Exploration Challenges in Assessing Ireland's Deep Low-Enthalpy Geothermal Energy Potential

    Science.gov (United States)

    Jones, A. G.; Muller, M. R.; Fullea, J.; Vozar, J.; Blake, S.; Delhaye, R.; Farrell, T.; Yeomans, C.; Loewer, M.; Reay, D.

    2012-12-01

    IRETHERM (www.iretherm.ie) is a new, academic-government-industry, collaborative research project, funded by Science Foundation Ireland, with the overarching objective of developing a holistic understanding of Ireland's low-enthalpy geothermal energy potential through integrated modelling of new and existing geophysical and geological data. A regional south-to-north trend in surface heat-flow is mapped across Ireland, ~40 to >80 mWm-2, but the source of the heat variation (whether crustal and/or lithospheric-mantle in origin) is unknown. With the exception of Permo-Triassic basins in Northern Ireland, hosting geothermal aquifers of promising but currently poorly-defined potential, rocks with high primary porosity have not been identified elsewhere. Whether any major Irish shear zones/faults might host a geothermal aquifer at depth is also unknown, although clusters of warm-springs in the vicinity of two major shear zones are promising. Our paper discusses the approaches and strategies that IRETHERM has adopted to meet the challenges of exploring for unknown deep geothermal resources (either hydrothermal aquifers or hot, dry rock) starting from a limited knowledge-base. IRETHERM's objectives over a four-year period are to: (i) Develop multi-parameter geophysical modelling and interpretation software tools that will enhance our ability to explore for and assess deep aquifers and granitic intrusions. (ii) Model and understand temperature variations in the upper-crust. Firstly, by building a 3-D model of crustal heat-production based on geochemical analysis of surface, borehole and mid- to lower-crustal xenolith samples. Secondly, by modelling, using a fully self-consistent 3-D approach, observed surface heat-flow variation as a function of variation in the structure and thermal properties of the crust and lithosphere, additionally constrained by surface elevation, geoid, gravity, seismic and magnetotelluric (MT) data. (iii) Test a strategic set of eight "type

  12. The Efficacy and Potential of Renewable Energy from Carbon Dioxide that is Sequestered in Sedimentary Basin Geothermal Resources

    Science.gov (United States)

    Bielicki, J. M.; Adams, B. M.; Choi, H.; Saar, M. O.; Taff, S. J.; Jamiyansuren, B.; Buscheck, T. A.; Ogland-Hand, J.

    2015-12-01

    Mitigating climate change requires increasing the amount of electricity that is generated from renewable energy technologies and while simultaneously reducing the amount of carbon dioxide (CO2) that is emitted to the atmosphere from present energy and industrial facilities. We investigated the efficacy of generating electricity using renewable geothermal heat that is extracted by CO2 that is sequestered in sedimentary basins. To determine the efficacy of CO2-Geothermal power production in the United States, we conducted a geospatial resource assessment of the combination of subsurface CO2 storage capacity and heat flow in sedimentary basins and developed an integrated systems model that combines reservoir modeling with power plant modeling and economic costs. The geospatial resource assessment estimates the potential resource base for CO2-Geothermal power plants, and the integrated systems model estimates the physical (e.g., net power) and economic (e.g., levelized cost of electricity, capital cost) performance of an individual CO2-Geothermal power plant for a range of reservoir characteristics (permeability, depth, geothermal temperature gradient). Using coupled inverted five-spot injection patterns that are common in CO2-enhanced oil recovery operations, we determined the well pattern size that best leveraged physical and economic economies of scale for the integrated system. Our results indicate that CO2-Geothermal plants can be cost-effectively deployed in a much larger region of the United States than typical approaches to geothermal electricity production. These cost-effective CO2-Geothermal electricity facilities can also be capacity-competitive with many existing baseload and renewable energy technologies over a range of reservoir parameters. For example, our results suggest that, given the right combination of reservoir parameters, LCOEs can be as low as $25/MWh and capacities can be as high as a few hundred MW.

  13. Naturally occurring arsenic in terrestrial geothermal systems of western Anatolia, Turkey: potential role in contamination of freshwater resources.

    Science.gov (United States)

    Bundschuh, Jochen; Maity, Jyoti Prakash; Nath, Bibhash; Baba, Alper; Gunduz, Orhan; Kulp, Thomas R; Jean, Jiin-Shuh; Kar, Sandeep; Yang, Huai-Jen; Tseng, Yu-Jung; Bhattacharya, Prosun; Chen, Chien-Yen

    2013-11-15

    Arsenic (As) contamination in terrestrial geothermal systems has been identified in many countries worldwide. Concentrations higher than 0.01 mg/L are detrimental to human health. We examined potential consequences for As contamination of freshwater resources based on hydrogeochemical investigations of geothermal waters in deep wells and hot springs collected from western Anatolia, Turkey. We analyzed samples for major ions and trace element concentrations. Temperature of geothermal waters in deep wells showed extreme ranges (40 and 230 °C), while, temperature of hot spring fluids was up to 90 °C. The Piper plot illustrated two dominant water types: Na-HCO3(-) type for geothermal waters in deep wells and Ca-HCO3(-) type for hot spring fluids. Arsenic concentration ranged from 0.03 to 1.5mg/L. Dominance of reduced As species, i.e., As(III), was observed in our samples. The Eh value ranged between -250 and 119 mV, which suggests diverse geochemical conditions. Some of the measured trace elements were found above the World Health Organization guidelines and Turkish national safe drinking water limits. The variation in pH (range: 6.4-9.3) and As in geothermal waters suggest mixing with groundwater. Mixing of geothermal waters is primarily responsible for contamination of freshwater resources and making them unsuitable for drinking or irrigation. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Overview of Resources for Geothermal Absorption Cooling for Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiaobing [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gluesenkamp, Kyle R [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Mehdizadeh Momen, Ayyoub [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-06-01

    This report summarizes the results of a literature review in three areas: available low-temperature/coproduced geothermal resources in the United States, energy use for space conditioning in commercial buildings, and state of the art of geothermal absorption cooling.

  15. Potential effects of geothermal energy conversion on Imperial Valley ecosystems. [Seven workshop presentations

    Energy Technology Data Exchange (ETDEWEB)

    Shinn, J.H. (ed.)

    1976-12-17

    This workshop on potential effcts of geothermal energy conversion on the ecology of Imperial Valley brought together personnel of Lawrence Livermore Laboratory and many collaborators under the sponsorship of the ERDA Imperial Valley Environmental Project (IVEP). The LLL Integrated Assessment Team identified the electric power potential and its associated effluents, discharges, subsidence, water requirements, land use, and noise. The Working Groups addressed the ecological problems. Water resource management problems include forces on water use, irrigation methods and water use for crops, water production, and water allocation. Agricultural problems are the contamination of edible crops and the reclamation of soil. A strategy is discussed for predevelopment baseline data and for identification of source term tracers. Wildlife resources might be threatened by habitat destruction, powerline impacts, noise and disturbance effects, gas emissions, and secondary impacts such as population pressure. Aquatic ecosystems in both the Salton Sea and fresh waters have potential hazards of salinity and trace metal effects, as well as existing stresses; baseline and bioassay studies are discussed. Problems from air pollution resulting from geothermal resource development might occur, particularly to vegetation and pollinator insects. Conversion of injury data to predicted economic damage isneeded. Finally, Imperial Valley desert ecosystems might be threatened by destruction of habitat and the possible effects on community structure such as those resulting from brine spills.

  16. National Geothermal Data System: Case Studies on Exploration and Development of Potential Geothermal Sites Through Distributed Data Sharing

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Arlene [DOE Geothermal Technologies Office; Allison, Lee [Executive Office of the State of Arizona (Arizona Geological Survey); Richard, Steve [Executive Office of the State of Arizona (Arizona Geological Survey); Caudill-Daugherty, Christy [Executive Office of the State of Arizona (Arizona Geological Survey); Patten, Kim [Executive Office of the State of Arizona (Arizona Geological Survey)

    2014-09-29

    The NGDS released version 1 of the system on April 30, 2014 using the US Geoscience Information Network (USGIN) as its data integration platform. NGDS supports the 2013 Open Data Policy, and as such, the launch was featured at the 2014 Energy Datapalooza. Currently, the NGDS features a comprehensive user interface for searching and accessing nearly 41,000 documents and more than 9 million data points shared by scores of data providers across the U.S. The NGDS supports distributed data sharing, permitting the data owners to maintain the raw data that is made available to the consumer. Researchers and industry have been utilizing the NGDS as a mechanism for promoting geothermal development across the country, from hydrothermal to ground source heat pump applications. Case studies in geothermal research and exploration from across the country are highlighted.

  17. Identifying Seismic Risk in the Appalachian Basin Geothermal Play Fairway Analysis Project Using Potential Fields, Seismicity, and the World Stress Map

    Science.gov (United States)

    Horowitz, F. G.

    2015-12-01

    A collaborative effort between Cornell University, Southern Methodist University, and West Virginia University has been sponsored by the US Department Of Energy to perform a Geothermal Play Fairway Analysis of the low temperature direct use potential for portions of the Appalachian sedimentary basin in New York, Pennsylvania and West Virginia - abbreviated here as GPFA-AB. One risk factor - of several being analyzed for the GPFA-AB - is whether a candidate location is near an active fault, and thereby potentially susceptible to induced seismicity from geothermal operations. Existing fault maps do not share the GPFA-AB boundaries or scale. Hence, their use leads to problems of uneven coverage, varying interpretation of faults vs. lineaments, and different mapping scales. For more uniformity across the GPFA-AB region, we use an analysis of gravity and magnetic fields. Multiscale edge Poisson wavelet analyses of potential fields ("worms") have a physical interpretation as the locations of lateral boundaries in a source distribution that exactly generates the observed field. Not all worms are faults, and of faults, only a subset might be active. Also, worms are only sensitive to steeply dipping structures. To identify some active structures, we plot worms and intra-plate earthquakes from the ISC, NEIC, and EarthScope TA catalogs. Worms within a small distance of epicenters are tracked spatially. To within errors in location, this is a sufficient condition to identify structures that might be active faults - which we categorize with higher risk than other structures. Plotting worms within World Stress Map σ1 directions yields an alternative approach to identifying activatable structures. Here, we use worms to identify structures with strikes favorably oriented for failure by Byerlee's law. While this is a necessary criterion for fault activation it is not a sufficient one - because we lack detailed information about stress magnitudes throughout the GPFA-AB region

  18. Ammonia synthesis at low temperatures

    DEFF Research Database (Denmark)

    Rod, Thomas Holm; Logadottir, Ashildur; Nørskov, Jens Kehlet

    2000-01-01

    have been carried out to evaluate its feasibility. The calculations suggest that it might be possible to catalytically produce ammonia from molecular nitrogen at low temperatures and pressures, in particular if energy is fed into the process electrochemically. (C) 2000 American Institute of Physics........ In contrast to the biological process, the industrial process requires high temperatures and pressures to proceed, and an explanation of this important difference is discussed. The possibility of a metal surface catalyzed process running at low temperatures and pressures is addressed, and DFT calculations...

  19. GIS based geothermal potential assessment: A case study from Western Anatolia, Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Tuefekci, Nesrin; Luetfi Suezen, M.; Guelec, Nilguen [Geological Engineering, Middle East Technical University, 06531 Ankara (Turkey)

    2010-01-15

    Potential geothermal areas are identified through investigation of spatial relations between geothermal occurrences and their surrounding geological phenomena in western Anatolia, Turkey. The identification is based on only publicly available data. It is expected that the study will guide further preliminary investigations performed for large areas having limited information. Magnetic anomaly, Bouger gravity anomaly, earthquake epicenter and lineament datasets are used for the analysis. The first is used without any modification whereas the rest are utilized to extract three evidence maps; distance to major grabens, Gutenberg-Richter b-value and distance to lineaments, respectively. Predictor maps are produced from these evidence maps as well as from the unprocessed magnetic anomaly map by applying two different binarization procedures. From each binarization procedure a favorability map is produced separately using Index Overlay (IO) and Weights of Evidence (WofE) methods. The findings reveal that weighting predictor maps according to spatial association between evidence maps and training points lead to more accurate prediction in both WofE and IO methods. The potential areas in the final maps are Aydin, Denizli, Manisa, Balikesir and Kutahya of which first two have been explored and exploited, and thus found to be favorable, while the rest are nearly unexplored. (author)

  20. LOW TEMPERATURE CATHODE SUPPORTED ELECTROLYTES

    Energy Technology Data Exchange (ETDEWEB)

    Harlan U. Anderson

    2000-03-31

    . However, they have the potential of being useful as an interface on the anode side of the electrolyte. NexTech has focused much of its effort during the past few months on establishing tape casting methods for porous LSM substrates. This work, performed under a separate DOE-funded program, involved tape casting formulations comprising LSM powders with bi-modal particle size distributions and fugitive pore forming additives. Sintered LSM substrates with porosities in the 30 to 40 vol% range, and pore sizes of 10 {approx} 20 microns have been prepared. In addition, tape casting formulations involving composite mixtures of LSM and Sm-doped ceria (SDC) have been evaluated. The LSM/SDC cathode substrates are expected to provide better performance at low temperatures. Characterization of these materials is currently underway.

  1. Certification testing at low temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Noss, P.W. [Packaging Technology, Tacoma, WA (United States); Ammerman, D.J. [Sandia National Labs., Albuquerque, NM (United States)

    2004-07-01

    Regulations governing the transport of radioactive materials require that most hypothetical accident condition tests or analyses consider the effects of the environmental temperature that most challenges package performance. For many packages, the most challenging temperature environment is the cold condition (-29 C according to U.S. regulations), primarily because the low temperature causes the highest free drop impact forces due to the higher strength of many energy-absorbing materials at this temperature. If it is decided to perform low temperature testing, it is only necessary that the relevant parts of the package have the required temperature prior to the drop. However, the details of performing a drop at low temperature can have a large influence on testing cost and technical effectiveness. The selection of the test site, the chamber and type of chilling equipment, instrumentation, and even the time of year are all important. Control of seemingly minor details such as the effect on internal pressure, placement of monitoring thermocouples, the thermal time constant of the test article, and icing of equipment are necessary to ensure a successful low temperature test. This paper will discuss these issues and offer suggestions based on recent experience.

  2. Low temperature aluminum soldering analysis

    Energy Technology Data Exchange (ETDEWEB)

    Peterkort, W.G.

    1976-09-01

    The investigation of low temperature aluminum soldering included the collection of spread factor and dihedral angle data for several solder alloys and a study of flux effects on aluminum. Selected solders were subjected to environmental tests and evaluated on the basis of tensile strength, joint resistance, visual appearance, and metallurgical analysis. A production line method for determining adequate flux removal was developed.

  3. Low-temperature magnetic refrigerator

    Science.gov (United States)

    Barclay, John A.

    1985-01-01

    The disclosure is directed to a low temperature 4 to 20 K. refrigeration apparatus and method utilizing a ring of magnetic material moving through a magnetic field. Heat exchange is accomplished in and out of the magnetic field to appropriately utilize the device to execute Carnot and Stirling cycles.

  4. Geothermal Energy for New Mexico: Assessment of Potential and Exploratory Drilling

    Energy Technology Data Exchange (ETDEWEB)

    Mark Person, Lara Owens, James Witcher

    2010-02-17

    This report summarizes the drilling operations and subsequent interpretation of thermal and geochemical data from the New Mexico Tech NMT-2GT (OSE RG- 05276 POD) test well. This slim hole was drilled along an elongate heat-flow anomaly at the base of the Socorro Mountains to better assess the geothermal resource potential (Socorro Peak geothermal system) on the western side of the New Mexico Tech campus in Socorro, New Mexico. The reservoir depth, hydraulic properties, temperature and chemistry were unknown prior to drilling. The purpose of the NMT-2GT (OSE RG-05276 POD) well was to explore the feasibility of providing geothermal fluids for a proposed district space heating system on the New Mexico Tech campus. With DOE cost over runs funds we completed NMT-2GT to a depth of 1102 feet at the Woods Tunnel drill site. Temperatures were nearly constant (41 oC ) between a depth of 1102 feet. Above this isothermal zone, a strong temperature gradient was observed (210 oC /km) beneath the water table consistent with vertical convective heat transfer. The existence of a groundwater upflow zone was further supported by measured vertical hydraulic head measurements which varied between about 258 feet at the water table to 155 feet at a depth of 1102 feet yielding a vertical hydraulic a gradient of about 0.1. If the upflow zone is 1 km deep, then a vertical flow rate is about 0.6 m/yr could have produced the observed curvature in the thermal profile. This would suggest that the deep bedrock permeability is about 20 mD. This is much lower than the permeability measured in a specific capacity aquifer test completed in 2009 within fracture Paleozoic sandstones near the water table (3000 D). Flow rates measured during drilling were measured using a v-notch weir. Flow rates were consistently around 1000 gpm. While the temperatures are lower than we had anticipated, this geothermal resource can still be developed to heat the NM Tech campus using heat pump technology.

  5. Potential impacts of artificial intelligence expert systems on geothermal well drilling costs:

    Energy Technology Data Exchange (ETDEWEB)

    Satrape, J.V.

    1987-11-24

    The Geothermal research Program of the US Department of Energy (DOE) has as one of its goals to reduce the cost of drilling geothermal wells by 25 percent. To attain this goal, DOE continuously evaluates new technologies to determine their potential in contributing to the Program. One such technology is artifical intelligence (AI), a branch of computer science that, in recent years, has begun to impact the marketplace in a number of fields. Expert systems techniques can (and in some cases, already have) been applied to develop computer-based ''advisors'' to assist drilling personnel in areas such as designing mud systems, casing plans, and cement programs, optimizing drill bit selection and bottom hole asssembly (BHA) design, and alleviating lost circulation, stuck pipe, fishing, and cement problems. Intelligent machines with sensor and/or robotic directly linked to AI systems, have potential applications in areas of bit control, rig hydraulics, pipe handling, and pipe inspection. Using a well costing spreadsheet, the potential savings that could be attributed to each of these systems was calculated for three base cases: a dry steam well at The Geysers, a medium-depth Imerial Valley well, and a deep Imperial Valley well. Based on the average potential savings to be realized, expert systems for handling lost circulations problems and for BHA design are the most likely to produce significant results. Automated bit control and rig hydraulics also exhibit high potential savings, but these savings are extremely sensitive to the assumptions of improved drilling efficiency and the cost of these sytems at the rig. 50 refs., 19 figs., 17 tabs.

  6. Underworld-GT Applied to Guangdong, a Tool to Explore the Geothermal Potential of the Crust

    Institute of Scientific and Technical Information of China (English)

    Steve Quenette; Yufei Xi; John Mansour; Louis Moresi; David Abramson

    2015-01-01

    Geothermal energy potential is usually discussed in the context of conventional or engi-neered systems and at the scale of an individual reservoir. Whereas exploration for conventional reser-voirs has been relatively easy, with expressions of resource found close to or even at the surface, explora-tion for non-conventional systems relies on temperature inherently increasing with depth and searching for favourable geological environments that maximise this increase. To utilitise the information we do have, we often assimilate available exploration data with models that capture the physics of the domi-nant underlying processes. Here, we discuss computational modelling approaches to exploration at a re-gional or crust scale, with application to geothermal reservoirs within basins or systems of basins. Tar-get reservoirs have (at least) appropriate temperature, permeability and are at accessible depths. We discuss the software development approach that leads to effective use of the tool Underworld. We ex-plore its role in the process of modelling, understanding computational error, importing and exporting geological knowledge as applied to the geological system underpinning the Guangdong Province, China.

  7. Assessment and evaluation of geothermal potential in Switzerland; Atlas des ressources geothermiques suisses

    Energy Technology Data Exchange (ETDEWEB)

    Andenmatten-Berthoud, N. [Geowatt AG, Zuerich (Switzerland); Kohl, T. [Eidgenossische Technische Hochschule (ETH), Institut de Geophysique, Zuerich (Switzerland)

    2003-07-01

    This report for the Swiss Federal Office of Energy presents the first part of a project that aims at assessing the geothermal energy potential of Switzerland's underground. Due to the presence of the Alps the Swiss underground is highly heterogeneous with numerous geologic faults. Geothermal energy assessment has to be carried out region after region. The first steps consisted in collecting existing geological and hydrogeological data and finding out the best appropriate methodology. Analysis was restricted to the Northwest of Switzerland (Basle-Zurich area), which has a dense population - an important factor for future applications - and is better known than others, thanks to previous studies performed in conjunction with site pre-selection for future radioactive waste disposal facilities. In this area, sandstones and limestones are found on the crystalline bottom rock. Mathematical models and computer codes were developed for interpolation and extrapolation of local and regional data. Three dimensional finite-element techniques were used. The results are presented in diagrams and maps.

  8. Potential geothermal energy use at the Naval Air Rework Facilities, Norfolk, Virginia and Jacksonville, Florida, and at the naval shipyard, Charleston, South Carolina

    Energy Technology Data Exchange (ETDEWEB)

    Costain, J.K.; Glover, L. III; Newman, R.W.

    1984-05-01

    The feasibility of geothermal energy use at naval installations in Norfolk, VA, Jacksonville, FL, and Charleston, SC was assessed. Geophysical and geological studies of the above areas were performed. Engineering and economic factors, affecting potential energy use, were evaluated. The Norfolk and Jacksonville facilities are identified as candidates for geothermal systems. System costs are predicted. Economic benefits of the proposed geothermal systems are forecast, using the net present value method of predicting future income.

  9. Geothermal energy

    Directory of Open Access Journals (Sweden)

    Manzella A.

    2017-01-01

    Full Text Available 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 the thermal energy stored in the underground, including any contained fluid, which is available for extraction and conversion into energy products. Electricity generation, which nowadays produces 73.7 TWh (12.7 GW of capacity worldwide, 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. Produced geothermal heat in the world accounts to 164.6 TWh, with a capacity of 70.9 GW. Geothermal technology, which has focused for decades 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.

  10. Geothermal energy

    Science.gov (United States)

    Manzella, A.

    2017-07-01

    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 the thermal energy stored in the underground, including any contained fluid, which is available for extraction and conversion into energy products. Electricity generation, which nowadays produces 73.7 TWh (12.7 GW of capacity) worldwide, 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. Produced geothermal heat in the world accounts to 164.6 TWh, with a capacity of 70.9 GW. Geothermal technology, which has focused for decades 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.

  11. High-potential Working Fluids for Next Generation Binary Cycle Geothermal Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Zia, Jalal [GE Global Research; Sevincer, Edip; Chen, Huijuan; Hardy, Ajilli; Wickersham, Paul; Kalra, Chiranjeev; Laursen, Anna Lis; Vandeputte, Thomas

    2013-06-29

    new optimal configuration for low temperature geothermal power production in the form of a supe

  12. High-potential Working Fluids for Next Generation Binary Cycle Geothermal Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Zia, Jalal [GE Global Research; Sevincer, Edip; Chen, Huijuan; Hardy, Ajilli; Wickersham, Paul; Kalra, Chiranjeev; Laursen, Anna Lis; Vandeputte, Thomas

    2013-06-29

    new optimal configuration for low temperature geothermal power production in the form of a supercritical ORC cycle based on a new vendor fluid.

  13. Extracting geothermal heat from mines

    Energy Technology Data Exchange (ETDEWEB)

    Ednie, H.

    2007-03-15

    In response to environmental concerns, research is underway to find alternative methods of generating energy, including the use of low-temperature geothermal heat from mines. Geothermal energy is the energy produced internally by radiogenic heat production and long-term cooling of the planet. Various applications can be used from this energy, including direct use for heating and electricity generation. The Earth/Mine Energy Resource Group (EMERG) at McGill University has worked on the development of alternative energies from both active and abandoned surface and underground mines. Geothermal heat from mines was once regarded as a benign energy source, particularly when compared to nuclear, oil, and coal. However, there is high potential for ground heat to be used as a sustainable solution to some energy requirements. EMERG's objective is to integrate alternate energy during the life of the mine, as well as after mine closure. Geothermal heat from mines will enable local communities to use this inexpensive source of energy for district heating of buildings, for drying food products, or for mining applications, such as heating deep oil sands deposits. Active or abandoned mines are ideal locations for geothermal systems. The first 100 metres underground is well suited for supply and storage of thermal energy. Due to the steady temperatures deep underground, geothermal sources are excellent fuels for heating and cooling systems. This article presented an example of a geothermal heat pump system used in Springhill Nova Scotia where Rock Can Am Ltd. is using floodwater from abandoned mines to heat and cool the company's facility at the site. The system produces annual savings of 600,000 kWh or $45,000 compared to conventional systems, proving that geothermal energy from abandoned or existing mines is a viable alternative energy source. Further efforts could result in it becoming a more effective and attractive option for the reclamation of abandoned mines

  14. Investigation of geothermal potential in the Waianae Caldera Area, Western Oahu, Hawaii. Assessment of Geothermal Resources in Hawaii: Number 2

    Energy Technology Data Exchange (ETDEWEB)

    Cox, M.E.; Sinton, J.M.; Thomas, D.M.; Mattice, M.D.; Kauahikaua, J.P.; Helstern, D.M.; Fan, P.

    1979-09-01

    Studies of Lualualei Valley, Oahu have been conducted to determine whether a thermal anomaly exists in the area and, if so, to identify sites at which subsurface techniques should be utilized to characterize the resource. Geologic mapping identifies several caldera and rift zone structures in the Valley and provides a tentative outline of their boundaries. Clay mineralogy studies indicate that minor geothermal alteration of near-surface rocks has occurred at some period in the history of the area. Schlumberger resistivity soundings indicate the presence of a low resistivity layer beneath the valley floor, which has been tentatively attributed to warm water-saturated basalt. Soil and groundwater chemistry studies outline several geochemical anomalies around the perimeter and within the inferred caldera boundaries. The observed anomalies strongly suggest a subsurface heat source. Recommendations for further exploratory work to confirm the presence of a geothermal reservoir include more intensive surveys in a few selected areas of the valley as well as the drilling of at least three shallow (1000-m) holes for subsurface geochemical, geological and geophysical studies.

  15. Low Temperature Heat Source Utilization Current and Advanced Technology

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, James H. Jr.; Dambly, Benjamin W.

    1992-06-01

    Once a geothermal heat source has been identified as having the potential for development, and its thermal, physical, and chemical characteristics have been determined, a method of utilization must be decided upon. This compendium will touch upon some of these concerns, and hopefully will provide the reader with a better understanding of technologies being developed that will be applicable to geothermal development in East Africa, as well as other parts of the world. The appendices contain detailed reports on Down-the-Well Turbo Pump, The Vapor-Turbine Cycle for Geothermal Power Generation, Heat Exchanger Design for Geothermal Power Plants, and a Feasibility Study of Combined Power and Water Desalting Plant Using Hot Geothermal Water. [DJE-2005

  16. Low Temperature Emissivity Measurement System

    Directory of Open Access Journals (Sweden)

    Jignesh A. Patel

    2014-05-01

    Full Text Available The emissivity of a material is the relative ability of its surface to emit energy by radiation. It is the ratio of energy radiated by a particular material to energy radiated by a black body at the same temperature. Knowledge about the low temperature emissivity of materials and coatings can be essential to the design of fusion cryoplants and in the thermal modeling for space satellite missions. The emittance of materials at cryogenics temperatures often cannot be predicted from room temperature data, but for computing radiative loads and infrared backgrounds this cryogenic data is often required. Measurement of the cryogenic emissivity of a highly reflective surface is a significant challenge: little thermal power is radiated from the sample, and the background radiation. However some researchers have measured emissivity at various low temperature ranges. Present work reports, the various emissivity measurement setup and their considerations.

  17. Final Report and Strategic Plan on the Feasibility Study to Assess Geothermal Potential on Warm Springs Reservation Lands. Report No. DOE/GO/15177

    Energy Technology Data Exchange (ETDEWEB)

    James Manion, Warm Springs Power & Water Enterprises; David McClain, McClain & Associates

    2007-05-17

    In 2005 the Confederated Tribes of Warm Springs Tribal Council authorized an evaluation of the geothermal development potential on the Confederated Tribes of Warm Springs Reservation of Oregon. Warm Springs Power & Water Enterprises obtained a grant from the U.S. Department of Energy to conduct a geological assessment and development estimate. Warm Springs Power & Water Enterprises utilized a team of expert consultants to conduct the study and develop a strategic plan. The resource assessment work was completed in 2006 by GeothermEx Inc., a consulting company specializing in geothermal resource assessments worldwide. The GeothermEx report indicates there is a 90% probability that a commercial geothermal resource exists on tribal lands in the Mt. Jefferson area. The geothermal resource assessment and other cost, risk and constraints information has been incorporated into the strategic plan.

  18. Geothermal heating systems for greenhouses

    Energy Technology Data Exchange (ETDEWEB)

    Silva, J.F.; Johnson, W.C.

    1980-08-12

    Ways to utilize low-temperature geothermally heated water for a flow-through system are presented. The geothermal energy used for this system is the waste heat discharged from space heating 500,000 square feet of floor space at Oregon Institute of Technology with geothermal water pumped directly from the campus wells. The information collected and analyzed is from data developed from operating a greenhouse on the Oregon Institute of Technology campus from December 1979 to April 1980. Methods for calculating heating requirements of greenhouses using geothermal energy were developed from the analyses of the data obtained. (MHR)

  19. Marine and land active-source seismic investigation of geothermal potential, tectonic structure, and earthquake hazards in Pyramid Lake, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Eisses, A.; Kell, A.; Kent, G. [UNR; Driscoll, N. [UCSD; Karlin, R.; Baskin, R. [USGS; Louie, J.; Pullammanappallil, S. [Optim

    2016-08-01

    Amy Eisses, Annie M. Kell, Graham Kent, Neal W. Driscoll, Robert E. Karlin, Robert L. Baskin, John N. Louie, Kenneth D. Smith, Sathish Pullammanappallil, 2011, Marine and land active-source seismic investigation of geothermal potential, tectonic structure, and earthquake hazards in Pyramid Lake, Nevada: presented at American Geophysical Union Fall Meeting, San Francisco, Dec. 5-9, abstract NS14A-08.

  20. Marine and land active-source seismic investigation of geothermal potential, tectonic structure, and earthquake hazards in Pyramid Lake, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Eisses, A.; Kell, A.; Kent, G. [UNR; Driscoll, N. [UCSD; Karlin, R.; Baskin, R. [USGS; Louie, J. [UNR; Pullammanappallil, S. [Optim

    2016-08-01

    Amy Eisses, Annie M. Kell, Graham Kent, Neal W. Driscoll, Robert E. Karlin, Robert L. Baskin, John N. Louie, Kenneth D. Smith, Sathish Pullammanappallil, 2011, Marine and land active-source seismic investigation of geothermal potential, tectonic structure, and earthquake hazards in Pyramid Lake, Nevada: presented at American Geophysical Union Fall Meeting, San Francisco, Dec. 5-9, abstract NS14A-08.

  1. Potential for by-product recovery in geothermal energy operations issue paper

    Energy Technology Data Exchange (ETDEWEB)

    None

    1982-07-01

    This document identifies and discusses the significant issues raised by the idea of recovering useful by-products from wastes (primarily spent brine) generated during geothermal power production. The physical availability of numerous valuable materials in geothermal brines has captured the interest of geothermal resource developers and other parties ever since their presence was known. The prospects for utilizing huge volumes of highly-saline geothermal brines for electricity generation in the Imperial Valley of California have served to maintain this interest in both private sector and government circles.

  2. Enhanced Geothermal System Potential for Sites on the Eastern Snake River Plain, Idaho

    Energy Technology Data Exchange (ETDEWEB)

    Robert K Podgorney; Thomas R. Wood; Travis L McLing; Gregory Mines; Mitchell A Plummer; Michael McCurry; Ahmad Ghassemi; John Welhan; Joseph Moore; Jerry Fairley; Rachel Wood

    2013-09-01

    The Snake River volcanic province overlies a thermal anomaly that extends deep into the mantle and represents one of the highest heat flow provinces in North America (Blackwell and Richards, 2004). This makes the Snake River Plain (SRP) one of the most under-developed and potentially highest producing geothermal districts in the United States. Elevated heat flow is typically highest along the margins of the topographic SRP and lowest along the axis of the plain, where thermal gradients are suppressed by the Snake River aquifer. Beneath this aquifer, however, thermal gradients rise again and may tap even higher heat flows associated with the intrusion of mafic magmas into the mid-crustal sill complex (e.g., Blackwell, 1989).

  3. Evaluation of geothermal potential of the basin and range province of New Mexico. Technical report

    Energy Technology Data Exchange (ETDEWEB)

    Landis, G.P.; Callender, J.F.; Elston, W.E.; Jiracek, G.R.; Kudo, A.M.; Woodward, L.A.; Swanberg, C.A.

    1976-06-01

    This continuing research is designed to provide an integrated geological, geophysical, and geochemical study of the geothermal energy potential of promising thermal anomalies in the Rio Grande rift, Basin and Range province, the Mogollon--Datil volcanic field of New Mexico. Specific objectives undertaken in this study include the following: (a) reconnaissance and detailed geologic mapping (Animas Valley, Radium Springs, Alum Mountain, Truth or Consequences, Ojo Caliente, Albuquerque---Belene basin, and San Ysidro); (b) geochemical studies including reconnaissance water sampling (Animas Valley, Radium Springs and Alum Mountain); and (c) geophysical surveys using deep electric-resistivity, gravity, and magnetic techniques (Radium Springs, Animas Valley and Truth or Consequences). The results of one and one-half summer field seasons and approximately two years of analytical work, laboratory research, and development of research equipment and facilities are covered. Publications, communications, and public service resulting from the first years of U.S.G.S. and State funding are listed in Appendix A.

  4. Survey of Potential Geothermal Exploration Sites at Newberry Volcano Deschutes County, Oregon.

    Energy Technology Data Exchange (ETDEWEB)

    Priest, George R.; Vogt, Beverly F.; Black, Gerald L.

    1983-01-01

    The study summarizes the current data, generates some new data, and recommends further steps which should be taken to investigate the electrical power production potential of Newberry volcano. The objective was to concentrate on data from the developable flanks of the volcano. All previous data on the geology, hydrology, and geophysics were summarized. A soil-mercury survey focused on the flanks of the volcano was conducted. Samples from 1000 km/sup 2/ of the volcano were analyzed for mercury content. All this information was utilized to evaluate (1) the likelihood of future discovery of electrical-quality geothermal fluids on the flanks, and (2) the most cost-effective means of improving the quality of available power generation estimates for the volcano. 37 figures.

  5. Mayer and virial series at low temperature

    CERN Document Server

    Jansen, Sabine

    2011-01-01

    We analyze the Mayer pressure-activity and virial pressure-density series for a classical system of particles in continuous configuration space at low temperature. Particles interact via a finite range potential with an attractive tail. We propose physical interpretations of the Mayer and virial series' radius of convergence, valid independently of the question of phase transition: the Mayer radius corresponds to a fast increase from very small to finite density, and the virial radius corresponds to a cross-over from monatomic to polyatomic gas. Our results have consequences for the search of a low density, low temperature solid-gas phase transition, consistent with the Lee-Yang theorem for lattice gases and with the continuum Widom-Rowlinson model.

  6. Technical geothermal potential of urban subsurface influenced by land surface effects

    Science.gov (United States)

    Rivera, Jaime A.; Blum, Philipp; Bayer, Peter

    2016-04-01

    Changes in land use are probably one of the most notorious anthropogenic perturbations in urban environments. They significantly change the coupled thermal regime at the ground surface leading in most cases to increased ground surface temperatures (GST). The associated elevated vertical heat fluxes act at different scales and can influence the thermal conditions in several tens of meters in the subsurface. Urban subsurface thus often stores a higher amount of heat than less affected rural surroundings. The stored heat is regarded as a potential source of low-enthalpy geothermal energy to supply the heating energy demands in urban areas. In this work, we explore the technical geothermal potential of urban subsurface via ground coupled heat pumps with borehole heat exchangers (BHE). This is tackled by semi-analytical line-source equations. The commonly used response factors or g-functions are modified to include transient land surface effects. By including this additional source of heat, the new formulation allows to analyse the effect of pre-existing urban warming as well as different exploitation schemes fulfilling standard renewable and sustainable criteria. In our generalized reference scenario, it is demonstrated that energy gains for a single BHE may be up to 40 % when compared to non-urbanized conditions. For a scenario including the interaction of multiple BHEs, results indicate that it would be possible to supply between 6 % and 27 % of the heating demands in Central European urban settlements in a renewable way. The methodology is also applied to a study case of the city of Zurich, Switzerland, where the detailed evolution of land use is available.

  7. IRETHERM: Magnetotelluric studies of Irish radiothermal granites and their geothermal energy potential

    Science.gov (United States)

    Farrell, T. F.; Jones, A. G.; Muller, M. R.; Feely, M.

    2013-12-01

    The IRETHERM project seeks to develop a strategic understanding of Ireland's deep geothermal energy potential through integrated modeling 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), heat-flow (HF) and subsurface temperatures. An understanding of the contribution of granites to the thermal field of Ireland is of key importance in assessing the geothermal energy potential of this low-enthalpy setting. This study focuses on the Leinster granite, the Galway granite and the buried Kentstown granite. Shallow (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. In the Galway granite batholith, the Costelloe-Murvey granite returned HP = 7 μWm-3 and HF = 77 mWm-2, measured at the Ros a Mhil borehole. The lower heat-flow encountered at the Ros a Mhil borehole suggests that the associated high heat production does not extend to great depth. The buried Kentstown granite has associated with it a significant negative Bouguer anomaly and was intersected by two mineral exploration boreholes at depths of 660 m and 485 m. Heat production has been measured at 2.4 μWm-3 in core samples taken from the weathered top 30m of the granite. The core of this study consists of an ambitious program of magnetotelluric (MT) and audio-magnetotelluric (AMT) data acquisition across the three granite bodies, extending 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 extend to depths of 2-5 km. Over the Galway granite, MT and AMT data have been collected at a total of 29 sites, with a further 46 sites to be collected in August 2013 (of these 75 sites, 33 will consist of AMT-only data

  8. Hydrogen Peroxide Cycling in Acidic Geothermal Environments and Potential Implications for Oxidative Stress

    Science.gov (United States)

    Mesle, M.; Beam, J.; Jay, Z.; Bodle, B.; Bogenschutz, E.; Inskeep, W.

    2014-12-01

    Hydrogen peroxide (H2O2) may be produced in natural waters via photochemical reactions between dissolved oxygen, organic carbon and light. Other reactive oxygen species (ROS) such as superoxide and hydroxyl radicals are potentially formed in environments with high concentrations of ferrous iron (Fe(II), ~10-100 μM) by reaction between H2O2 and Fe(II) (i.e., Fenton chemistry). Thermophilic archaea and bacteria inhabiting acidic iron-oxide mats have defense mechanisms against both extracellular and intracellular peroxide, such as peroxiredoxins (which can degrade H2O2) and against other ROS, such as superoxide dismutases. Biological cycling of H2O2 is not well understood in geothermal ecosystems, and geochemical measurements combined with molecular investigations will contribute to our understanding of microbial response to oxidative stress. We measured H2O2 and other dissolved compounds (Fe(II), Fe(III), H2S, O2), as well as photon flux, pH and temperature, over time in surface geothermal waters of several acidic springs in Norris Geyser Basin, Yellowstone National Park, WY (Beowulf Spring and One Hundred Spring Plain). Iron-oxide mats were sampled in Beowulf Spring for on-going analysis of metatranscriptomes and RT-qPCR assays of specific stress-response gene transcription (e.g., superoxide dismutases, peroxiredoxins, thioredoxins, and peroxidases). In situ analyses show that H2O2 concentrations are lowest in the source waters of sulfidic systems (ca. 1 μM), and increase by two-fold in oxygenated waters corresponding to Fe(III)-oxide mat formation (ca. 2 - 3 μM). Channel transects confirm increases in H2O2 as a function of oxygenation (distance). The temporal dynamics of H2O2, O2, Fe(II), and H2S in Beowulf geothermal waters were also measured during a diel cycle, and increases in H2O2 were observed during peak photon flux. These results suggest that photochemical reactions may contribute to changes in H2O2. We hypothesize that increases in H2O2 and O2

  9. Exploration of the enhanced geothermal system (EGS) potential of crystalline rocks for district heating (Elbe Zone, Saxony, Germany)

    Science.gov (United States)

    Förster, Andrea; Förster, Hans-Jürgen; Krentz, Ottomar

    2016-12-01

    This paper addresses aspects of a baseline geothermal exploration of the thermally quiescent Elbe Zone (hosting the cities of Meissen and Dresden) for a potential deployment of geothermal heat in municipal heating systems. Low-permeable to impermeable igneous and metamorphic rocks constitute the major rock types at depth, implying that an enhanced geothermal system needs to be developed by creating artificial flow paths for fluids to enhance the heat extraction from the subsurface. The study includes the development of geological models for two areas on the basis of which temperature models are generated at upper crustal scale. The models are parameterized with laboratory-measured rock thermal properties (thermal conductivity k, radiogenic heat production H). The uncertainties of modelled temperature caused by observed variations of k and H and inferred mantle heat flow are assessed. The study delineates highest temperatures within the intermediate (monzonite/syenite unit) and mafic rocks (diorite/monzodiorite unit) forming the deeper portions of the Meissen Massif and, specifically for the Dresden area, also within the low-metamorphic rocks (slates/phyllites/quartzites) of the Elbtalschiefergebirge. Boreholes 3-4 km deep need to be drilled to reach the envisioned economically favourable temperatures of 120 °C. The metamorphic and mafic rocks exhibit low concentrations of U and Th, thus being advantageous for a geothermal use. For the monzonite/syenite unit of high heat production ( 6 µW m-3) in the Meissen Massif, the mobilization of Th and U into the geothermal working fluid is assumed to be minor, although their various radioactive decay products will be omnipresent during geothermal use.

  10. Final Report Low-temperature Resource Assessment Program

    Energy Technology Data Exchange (ETDEWEB)

    Lienau, P.J. [Geo-Heat Center, Oregon Institute of Technology, Klamath Falls, OR (US); Ross, H. [Earth Sciences and Resources Institute, University of Utah

    1996-02-01

    The U.S. Department of Energy - Geothermal Division (DOE/GD) recently sponsored the Low-Temperature Resource Assessment project to update the inventory of the nation's low- and moderate-temperature geothermal resources and to encourage development of these resources. A database of 8,977 thermal wells and springs that are in the temperature range of 20 degrees Celsius to 150 degrees Celsius has been compiled for ten western states, an impressive increase of 82% compared to the previous assessments. The database includes location, descriptive data, physical parameters, water chemistry and references for sources of data. Computer-generated maps are also available for each state. State Teams have identified 48 high-priority areas for near-term comprehensive resource studies and development. Resources with temperatures greater than 50 degrees Celsius located within 8 km of a population center were identified for 271 collocated cities. Geothermal energy costevaluation software has been developed to quickly identify the cost of geothermally supplied heat to these areas in a fashion similar to that used for conventionally fueled heat sources.

  11. Low-temperature resource assessment program. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Lienau, P.J. [Oregon Inst. of Tech., Klamath Falls, OR (United States). Geo-Heat Center; Ross, H. [Utah Univ., Salt Lake City, UT (United States). Earth Sciences and Resources Inst.

    1996-02-01

    The US Department of Energy - Geothermal Division (DOE/GD) recently sponsored the Low-Temperature Resource Assessment project to update the inventory of the nation`s low- and moderate-temperature geothermal resources and to encourage development of these resources. A database of 8,977 thermal wells and springs that are in the temperature range of 20{degrees}C to 150{degrees}C has been compiled for ten western states, an impressive increase of 82% compared to the previous assessments. The database includes location, descriptive data, physical parameters, water chemistry and references for sources of data. Computer-generated maps are also available for each state. State Teams have identified 48 high-priority areas for near-term comprehensive resource studies and development. Resources with temperatures greater than 50{degrees}C located within 8 km of a population center were identified for 271 collocated cities. Geothermal energy cost evaluation software has been developed to quickly identify the cost of geothermally supplied heat to these areas in a fashion similar to that used for conventionally fueled heat sources.

  12. Mapping the geothermal potential of fault zones in the Belgium-Netherlands border region

    NARCIS (Netherlands)

    Loveless, S.; Pluymaekers, M.P.D.; Lagrou, D.; Boever, E. de; Doornenbal, H.; Laenen, B.

    2014-01-01

    Faults can determine the success or failure of low enthalpy geothermal projects. This is due to their capacity to behave as pathways or baffles to geothermal water (or both simultaneously) and their prevalence throughout the subsurface. Here we present an initial assessment of the possibility for fa

  13. Mapping the geothermal potential of fault zones in the Belgium-Netherlands border region

    NARCIS (Netherlands)

    Loveless, S.; Pluymaekers, M.P.D.; Lagrou, D.; Boever, E. de; Doornenbal, H.; Laenen, B.

    2014-01-01

    Faults can determine the success or failure of low enthalpy geothermal projects. This is due to their capacity to behave as pathways or baffles to geothermal water (or both simultaneously) and their prevalence throughout the subsurface. Here we present an initial assessment of the possibility for

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1986-07-01

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

  15. Low temperature-pressure batch experiments and field push-pull tests: Assessing potential effects of an unintended CO2 release from CCUS projects on groundwater chemistry

    Science.gov (United States)

    Mickler, P. J.; Yang, C.; Lu, J.; Reedy, R. C.; Scanlon, B. R.

    2012-12-01

    primarily through carbonate dissolution which releases Ca and elements that substitute for Ca in crystal lattices. Silicate weathering releases primarily Si and K at lower rates. Chemical changes with the addition of CO2 may initially mobilize As, Mo, V, Zn, Se and Cd but these elements become immobile in the lowered pH water and sorb onto aquifer minerals. A combined laboratory batch experiment and field push-pull test in fresh water aquifers overlying CCUS projects will best characterize the response of the aquifer to increased pCO2. The long experimental duration of the batch experiments may allow reactions to reach equilibrium however; reaction rates may be artificially high due to increased mineral surface areas. Field based push-pull tests offer a more realistic water rock ratio and test a much larger volume of aquifer material but the test must be shorter in duration because the high pCO2 water is subject to mixing with low pCO2 background water and migration away from the test well with groundwater flow. A comparison of the two methods best characterizes the potential effects on groundwater chemistry

  16. Geothermal energy

    Directory of Open Access Journals (Sweden)

    Manzella A.

    2015-01-01

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

  17. Geothermal energy

    Science.gov (United States)

    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.

  18. The geothermal potential of the Campania volcanic district and new heat exchanger technologies for exploitation of highly urbanised areas.

    Science.gov (United States)

    Carlino, S.; Somma, R.; Troiano, A.; Di Giuseppe, M. G.; Troise, C.; De Natale, G.

    2012-04-01

    The geothermal research in Campania region (Italy), started since the 1930, and continued until the '80 by the SAFEN, ENEL and AGIP companies. Such exploration activity highlighted that most of the volcanic districts of the Campania Region have a very high geothermal gradient and heat flow. In particular, inside the Campi Flegrei caldera and at Ischia island the geothermal gradient measured inside the deep wells reaches temperatures above 100° C between few tens and few hundreds of metres of depth, while the heat flow varies between 120-160 mWm-2 at Agnano and Mofete (Campi Flegrei main drill sites) to more than 500 mWm-2 at Ischia island (south-western sector). A general review of the available literature data (temperature at depth, stratigraphic sections, logs etc.) of the deep wells (down to 3 km b.s.l.) allowed us to quantify the geothermal potential (thermal and electric) of such district. The geothermal potential is about 6 GWy for the Campi Flegrei (Mofete and S. Vito sectors) and 11 GWy for the Ischia island (south-western sector) showing a geothermal reservoir with water and vapour dominant respectively. This results in strong potential interest for economic exploitation of the geothermal resource, both in the range of low-medium enthalpy at few hundreds of meters depth and of high enthalpy at depths of 1-2 km. In this study we try to model the effectiveness of new technologies of boreholes heat exchangers, which would allow to avoid fluid withdrawal, then strongly decreasing the environmental impact. The proposed technology consists of a double-pipe placed in a borehole heat exchange that can work coupled with an ORC. The two pipes, one inside the other, are located in the well in order to transfer the thermal energy to the working fluid during the descent in the external pipe and then go back through the internal pipe properly isolated. We propose a complete design of the borehole heat exchangers. The design activity is performed on a theoretical basis

  19. Use of geothermal heat for crop drying and related agricultural applications. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, T.J.; Wright, T.C.; Fein, E.; Munson, T.R.; Richmond, R.C.

    1978-03-01

    Observations led to the selection of the alfalfa dehydration industry for in-depth analysis of the application of moderate-temperature geothermal heat. Six geothermal heat exchanger/dryer configurations were examined. A low-temperature conveyor dryer using geothermal water to supply all required heat was chosen for site-specific analysis, the retrofitting of a large alfalfa dehydration plant within the Heber KGRA in the Imperial Valley, California. Even in the most favorable scenario--sharing a geothermal pipeline with the neighboring fertilizer plant--geothermal retrofitting would increase the price of the alfalfa ''dehy'' about 40 percent. The geothermal brine is estimated to cost $2.58/million Btu's compared with a 1977 natural gas cost of $1.15. Capital cost for heat exchangers and the new dryers is estimated at $3.3 million. The Heber plant appeared to offer the only good opportunity for geothermal retrofitting of an existing alfalfa dehydration plant. Construction of new plants at geothermal resource sites cannot be justified due to the uncertain state of the ''dehy'' industry. Use of geothermal heat for drying other crops may be much more promising. The potato dehydration industry, which is concentrated in the geothermal-rich Snake River Valley of Idaho, appears to offer good potential for geothermal retrofitting; about 4.7 x 10{sup 12}Btu's are used annually by plants within 50 miles of resources. Drying together at the geothermal wellhead several crops that have interlocking processing seasons and drying-temperature requirements may be quite attractive. The best ''multicrop drying center'' site identified was at Power Ranch Wells, Arizona; 34 other sites were defined. Agricultural processing applications other than drying were investigated briefly.

  20. Geothermal handbook

    Science.gov (United States)

    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

  1. Database on the geothermal resources of Algeria

    Energy Technology Data Exchange (ETDEWEB)

    Kedaid, Fatima Zohra [Centre de Developpement des Energies Renouvelables, B.P. 62, route de l' Observatoire, Bouzareah, Alger (Algeria)

    2007-06-15

    The paper describes a database on the low-temperature geothermal resources of Algeria that includes information on thermal springs and wells, a description of hot water resources, and thematic maps. (author)

  2. Internal structure of fault zones in geothermal reservoirs: Examples from palaeogeothermal fields and potential host rocks

    Science.gov (United States)

    Leonie Philipp, Sonja; Reyer, Dorothea; Meier, Silke; Bauer, Johanna F.; Afşar, Filiz

    2014-05-01

    Fault zones commonly have great effects on fluid transport in geothermal reservoirs. During fault slip all the pores and small fractures that meet with the slip plane become interconnected so that the inner part of the fault, the fault core, consisting of breccia or gouge, may suddenly develop a very high permeability. This is evidenced, for example by networks of mineral veins in deeply eroded fault zones in palaeogeothermal fields. Inactive faults, however, may have low permeabilities and even act as flow barriers. In natural and man-made geothermal reservoirs, the orientation of fault zones in relation to the current stress field and their internal structure needs be known as accurately as possible. One reason is that the activity of the fault zone depends on its angle to the principal stress directions. Another reason is that the outer part of a fault zone, the damage zone, comprises numerous fractures of various sizes. Here we present field examples of faults, and associated joints and mineral veins, in palaeogeothermal fields, and potential host rocks for man-made geothermal reservoirs, respectively. We studied several localities of different stratigraphies, lithologies and tectonic settings: (1) 58 fault zones in 22 outcrops from Upper Carboniferous to Upper Cretaceous in the Northwest German Basin (siliciclastic, carbonate and volcanic rocks); (2) 16 fault zones in 9 outcrops in Lower Permian to Middle Triassic (mainly sandstone, limestone and granite) in the Upper Rhine Graben; and (3) 74 fault zones in two coastal sections of Upper Triassic and Lower Jurassic age (mudstones and limestone-marl alternations) in the Bristol Channel Basin, UK. (1) and (2) are outcrop analogues of geothermal reservoir horizons, (3) represent palaeogeothermal fields with mineral veins. The field studies in the Northwest German Basin (1) show pronounced differences between normal-fault zones in carbonate and clastic rocks. In carbonate rocks clear damage zones occur that are

  3. Research status of geothermal resources in China

    Science.gov (United States)

    Zhang, Lincheng; Li, Guang

    2017-08-01

    As the representative of the new green energy, geothermal resources are characterized by large reserve, wide distribution, cleanness and environmental protection, good stability, high utilization factor and other advantages. According to the characteristics of exploitation and utilization, they can be divided into high-temperature, medium-temperature and low-temperature geothermal resources. The abundant and widely distributed geothermal resources in China have a broad prospect for development. The medium and low temperature geothermal resources are broadly distributed in the continental crustal uplift and subsidence areas inside the plate, represented by the geothermal belt on the southeast coast, while the high temperature geothermal resources concentrate on Southern Tibet-Western Sichuan-Western Yunnan Geothermal Belt and Taiwan Geothermal Belt. Currently, the geothermal resources in China are mainly used for bathing, recuperation, heating and power generation. It is a country that directly makes maximum use of geothermal energy in the world. However, China’s geothermal power generation, including installed generating capacity and power generation capacity, are far behind those of Western European countries and the USA. Studies on exploitation and development of geothermal resources are still weak.

  4. Potential use of geothermal resources in the Snake River Basin: an environmental overview. Volume I

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, S.G.; Russell, B.F.; Sullivan, J.F. (eds.)

    1979-09-01

    Environmental baseline data for the Snake River Plain known geothermal resource areas (KGRAs) are evaluated for geothermal development. The objective is to achieve a sound data base prior to geothermal development. These KGRAs are: Vulcan Hot Springs, Crane Creek, Castle Creek, Bruneau, Mountain Home, Raft River, Island Park, and Yellowstone. Air quality, meteorology, hydrology, water quality, soils, land use, geology, subsidence, seismicity, terrestrial and aquatic ecology, demography, socioeconomics, and heritage resources are analyzed. This program includes a summary of environmental concerns related to geothermal development in each of the KGRAs, an annotated bibliography of reference materials (Volume II), detailed reports on the various program elements for each of the KGRAs, a program plan identifying future research needs, and a comprehensive data file.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1993-05-01

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

  6. The Low Temperature Microgravity Physics Facility Project

    Science.gov (United States)

    Chui, T.; Holmes, W.; Lai, A.; Croonquist, A.; Eraker, J.; Abbott, R.; Mills, G.; Mohl, J.; Craig, J.; Balachandra, B.; hide

    2000-01-01

    We describe the design and development of the Low Temperature Microgravity Physics Facility, which is intended to provide a unique environment of low temperature and microgravity for the scientists to perform breakthrough investigations on board the International Space Station.

  7. The Low Temperature Microgravity Physics Facility

    Science.gov (United States)

    Pensinger, J. F.; Chui, T.; Croonquist, A.; Larson, M.; Liu, F.

    2002-01-01

    The Low Temperature Microgravity Physics Facility currently in the design phase is a multiple user and multiple flight facility intended to provide a long duration low temperature environment onboard the International Space Station.

  8. Evaluation of state taxes and tax incentives and their impact on the development of geothermal energy in western states

    Energy Technology Data Exchange (ETDEWEB)

    Bronder, L.D.; Meyer, R.T.

    1981-01-01

    The economic impact of existing and prospective state taxes and tax incentives on direct thermal applications of geothermal energy are evaluated. Study area is twelve western states which have existing and potential geothermal activities. Economic models representing the geothermal producer and business enterprise phases of four industrial/commercial uses of geothermal energy are synthesized and then placed in the existing tax structures of each state for evaluation. The four enterprises are a commercial greenhouse (low temperature process heat), apartment complex (low temperature space heat), food processor (moderate temperature process heat), and small scale energy system (electrical and direct thermal energy for a small industrial park). The effects of the state taxations on net profits and tax revenues are determined. Tax incentives to accelerate geothermal development are also examined. The magnitudes of total state and local tax collections vary considerably from state to state, which implies that geothermal producers and energy-using businesses may be selective in expanding or locating their geothermal operations.

  9. Geothermal potential for commercial and industrial direct heat applications in Salida, Colorado. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Coe, B.A.; Dick, J.D.; Galloway, M.J.; Gross, J.T.; Meyer, R.T.; Raskin, R.; Zocholl, J.R.

    1982-10-01

    The Salida Geothermal Prospect (Poncha Hot Springs) was evaluated for industrial and commercial direct heat applications at Salida, Colorado, which is located approximately five miles east of Poncha Hot Springs. Chaffee Geothermal, Ltd., holds the geothermal leases on the prospect and the right-of-way for the main pipeline to Salida. The Poncha Hot Springs are located at the intersection of two major structural trends, immediately between the Upper Arkansas graben and the Sangre de Cristo uplift. Prominent east-west faulting occurs at the actual location of the hot springs. Preliminary exploration indicates that 1600 gpm of geothermal fluid as hot as 250/sup 0/F is likely to be found at around 1500 feet in depth. The prospective existing endusers were estimated to require 5.02 x 10/sup 10/ Btu per year, but the total annual amount of geothermal energy available for existing and future endusers is 28.14 x 10/sup 10/ Btu. The engineering design for the study assumed that the 1600 gpm would be fully utilized. Some users would be cascaded and the spent fluid would be cooled and discharged to nearby rivers. The economic analysis assumes that two separate businesses, the energy producer and the energy distributor, are participants in the geothermal project. The producer would be an existing limited partnership, with Chaffee Geothermal, Ltd. as one of the partners; the distributor would be a new Colorado corporation without additional income sources. Economic evaluations were performed in full for four cases: the Base Case and three alternate scenarios. Alternate 1 assumes a three-year delay in realizing full production relative to the Base Case; Alternate 2 assumes that the geothermal reservoir is of a higher quality than is assumed for the Base Case; and Alternate 3 assumes a lower quality reservoir. 11 refs., 34 figs., 40 tabs.

  10. Possibilities of using carbon dioxide as fillers for heat pipe to obtain low-potential geothermal energy

    Directory of Open Access Journals (Sweden)

    Malcho M.

    2013-04-01

    Full Text Available The use of low-potential heat is now possible especially in systems using heat pumps. There is a presumption that the trend will continue. Therefore, there is a need to find ways to be systems with a heat pump efficiencies. The usage of heat pipes seems to be an appropriate alternative to the establishedtechnology of obtaining heat through in-debt probes. This article describes a series of experiments on simulator for obtaining low-potential geothermal energy, in order to find the optimal amount of carbon dioxide per meter length of the heat pipe. For orientation and understanding of the conclusions of theexperiment, the article has also a detailed description of the device which simulates the transport of heat through geothermal heat pipes.

  11. Coupling geophysical investigation with hydrothermal modeling to constrain the enthalpy classification of a potential geothermal resource.

    Science.gov (United States)

    White, Jeremy T.; Karakhanian, Arkadi; Connor, Chuck; Connor, Laura; Hughes, Joseph D.; Malservisi, Rocco; Wetmore, Paul

    2015-01-01

    An appreciable challenge in volcanology and geothermal resource development is to understand the relationships between volcanic systems and low-enthalpy geothermal resources. The enthalpy of an undeveloped geothermal resource in the Karckar region of Armenia is investigated by coupling geophysical and hydrothermal modeling. The results of 3-dimensional inversion of gravity data provide key inputs into a hydrothermal circulation model of the system and associated hot springs, which is used to evaluate possible geothermal system configurations. Hydraulic and thermal properties are specified using maximum a priori estimates. Limited constraints provided by temperature data collected from an existing down-gradient borehole indicate that the geothermal system can most likely be classified as low-enthalpy and liquid dominated. We find the heat source for the system is likely cooling quartz monzonite intrusions in the shallow subsurface and that meteoric recharge in the pull-apart basin circulates to depth, rises along basin-bounding faults and discharges at the hot springs. While other combinations of subsurface properties and geothermal system configurations may fit the temperature distribution equally well, we demonstrate that the low-enthalpy system is reasonably explained based largely on interpretation of surface geophysical data and relatively simple models.

  12. Use of low-quality geothermal heat in grain drying and related agricultural applications. Quarterly report, January 4, 1977-April 4, 1977

    Energy Technology Data Exchange (ETDEWEB)

    Gordon, T.J.; Wright, T.C.; Fein, E.; Munson, T.R.; Richmond, R.C.

    1977-04-01

    State profiles of geothermal area crop acreage, production, dollar value, and drying energy were begun. Technical feasibility analyses were done for four geothermally augmented, natural gas alfalfa dryers, a steam-tube predryer design, and an all-geothermal conveyor dryer; costing is underway. Details of a geothermal conveyor-type alfalfa dryer in New Zealand were obtained. A computer simulation of rotary drum dehydration was acquired and extensively modified for use in determining operating parameters and performance for low-temperature geothermal alfalfa dryers. The most important nutrients in alfalfa from a market standpoint were determined and experimental results assessed showing the changes nutrients undergo in conventional drying; indications are that low-temperature drying will yield an acceptable product. Innovative techniques for alfalfa processing were identified for potential geothermal application. Markets, institutional characteristics, and the outlook for growth in the dehydrated alfalfa industry were examined, and a list of existing plants near geothermal resources was compiled. Only three plants were close enough to permit geothermal retrofitting; two plants, at El Centro, California, and Twin Falls, Idaho, are the subject of site-specific studies in which detailed costs and siting options are to be analyzed.

  13. An inventory of Geothermal Resources in Nebraska: State-Coupled Program between US Department of Energy and The University of Nebraska. Final report, June 30, 1983

    Energy Technology Data Exchange (ETDEWEB)

    Gosnold, William D.; Eversoll, Duane, A.; Messenger, Karen A.; Carlson, Marvin P.

    1983-06-30

    The goal of the State Coupled Resource Assessment Program is to identify and evaluate geothermal resources in the state, particularly low-temperature potential. Eight tasks were identified and documented in this report as follows: (1) Bottom-hole Temperature Survey; (2) Heat Flow and Temperature Gradient Survey; (3) Data Translation studies; (4) Gravity Data; (5) Substate Regions; (6) Information Dissemination; (7) State Geothermal Map; (8) Reports. The project had three major products: (1) a map ''Geothermal Resources of Nebraska''; (2) a significant amount of thermal data collected and documented within the state; and (3) a series of publications, presentations and meetings.

  14. An inventory of Geothermal Resources in Nebraska: State-Coupled Program between US Department of Energy and The University of Nebraska. Final report, June 30, 1983

    Energy Technology Data Exchange (ETDEWEB)

    Gosnold, William D.; Eversoll, Duane, A.; Messenger, Karen A.; Carlson, Marvin P.

    1983-06-30

    The goal of the State Coupled Resource Assessment Program is to identify and evaluate geothermal resources in the state, particularly low-temperature potential. Eight tasks were identified and documented in this report as follows: (1) Bottom-hole Temperature Survey; (2) Heat Flow and Temperature Gradient Survey; (3) Data Translation studies; (4) Gravity Data; (5) Substate Regions; (6) Information Dissemination; (7) State Geothermal Map; (8) Reports. The project had three major products: (1) a map ''Geothermal Resources of Nebraska''; (2) a significant amount of thermal data collected and documented within the state; and (3) a series of publications, presentations and meetings.

  15. Volcanology and volcanic activity with a primary focus on potential hazard impacts for the Hawaii geothermal project

    Energy Technology Data Exchange (ETDEWEB)

    Moore, R.B. [Federal Center, Denver, CO (United States); Delaney, P.T. [2255 North Gemini Drive, Flagstaff, AZ (United States); Kauahikaua, J.P. [Geological Survey, Hawaii National Park, HI (United States). Hawaiian Volcano Observatory

    1993-10-01

    This annotated bibliography reviews published references about potential volcanic hazards on the Island of Hawaii that are pertinent to drilling and operating geothermal wells. The first two sections of this annotated bibliography list the most important publications that describe eruptions of Kilauea volcano, with special emphasis on activity in and near the designated geothermal subzones. References about historic eruptions from Mauna Loa`s northeast rift zone, as well as the most recent activity on the southern flank of dormant Mauna Kea, adjacent to the Humu`ula Saddle are described. The last section of this annotated bibliography lists the most important publications that describe and analyze deformations of the surface of Kilauea and Mauna Loa volcanoes.

  16. Accelerating Geothermal Research (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    2014-05-01

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

  17. Mineral and geothermal resource potential of the Mount Hood Wilderness, Clackamas and Hood River Counties, Oregon. Summary report and map

    Energy Technology Data Exchange (ETDEWEB)

    Keith, T.E.C.; Causey, J.D.

    1982-01-01

    The potential for near-surface mineral resources in the Mount Hood Wilderness is low. Geochemical data suggest two areas of weak epithermal mineralization in the Zigzag Mountain part of the wilderness: (1) the Lost Creek-Burnt Lake-Cast Creek-Short Creek area on the north side of Zigzag Mountain where vein-type lead-zinc-silver mineralization occurs; and (2) the Lady Creek-Laurel Hill area on the south side of Zigzag Mountain where the upper part of a quartz diorite pluton has associated propylitic alteration resulting in some porphyry-type copper, gold, silver, lead, and zinc mineralization. Geothermal-resource potential for low- to intermediate-temperature (less than 248/sup 0/F, 120/sup 0/C) hot-water systems in the wilderness is moderate to high. Part of the wilderness is classified as a Known Geothermal Resources Area (KGRA) and two parts have been included in geothermal lease areas. Rock and gravel sources are present within the wilderness; however, quantities of similar and more accessible deposits are available outside the wilderness. Deposits outside the wilderness are large enough to supply local demand in the foreseeable future.

  18. Wellbore and groundwater temperature distribution eastern Snake River Plain, Idaho: Implications for groundwater flow and geothermal potential

    Science.gov (United States)

    McLing, Travis L.; Smith, Richard P.; Smith, Robert W.; Blackwell, David D.; Roback, Robert C.; Sondrup, Andrus J.

    2016-06-01

    A map of groundwater temperatures from the Eastern Snake River Plain (ESRP) regional aquifer can be used to identify and interpret important features of the aquifer, including aquifer flow direction, aquifer thickness, and potential geothermal anomalies. The ESRP is an area of high heat flow, yet most of this thermal energy fails to reach the surface, due to the heat being swept downgradient by the aquifer to the major spring complexes near Thousand Springs, ID, a distance of 300 km. Nine deep boreholes that fully penetrate the regional aquifer display three common features: (1) high thermal gradients beneath the aquifer, corresponding to high conductive heat flow in low-permeability hydrothermally-altered rocks; (2) isothermal temperature profiles within the aquifer, characteristic of an actively flowing groundwater; and (3) moderate thermal gradients in the vadose zone with values that indicate that over half of the geothermal heat flow is removed by advective transport in the regional aquifer system. This study utilized temperature data from 250 ESRP aquifer wells to evaluate regional aquifer flow direction, aquifer thickness, and potential geothermal anomalies. Because the thermal gradients are typically low in the aquifer, any measurement of groundwater temperature is a reasonable estimate of temperature throughout the aquifer thickness, allowing the construction of a regional aquifer temperature map for the ESRP. Mapped temperatures are used to identify cold thermal plumes associated with recharge from tributary valleys and adjacent uplands, and warm zones associated with geothermal input to the aquifer. Warm zones in the aquifer can have various causes, including local circulation of groundwater through the deep conductively dominated region, slow groundwater movement in low-permeability regions, or localized heat flow from deeper thermal features.

  19. A new classification scheme for deep geothermal systems based on geologic controls

    Science.gov (United States)

    Moeck, I.

    2012-04-01

    A key element in the characterization, assessment and development of geothermal energy systems is the resource classification. Throughout the past 30 years many classifications and definitions were published mainly based on temperature and thermodynamic properties. In the past classification systems, temperature has been the essential measure of the quality of the resource and geothermal systems have been divided into three different temperature (or enthalpy) classes: low-temperature, moderate-temperature and high-temperature. There are, however, no uniform temperature ranges for these classes. It is still a key requirement of a geothermal classification that resource assessment provides logical and consistent frameworks simplified enough to communicate important aspects of geothermal energy potential to both non-experts and general public. One possible solution may be to avoid classifying geothermal resources by temperature and simply state the range of temperatures at the individual site. Due to technological development, in particular in EGS (Enhanced Geothermal Systems or Engineered Geothermal Systems; both terms are considered synonymously in this thesis) technology, currently there are more geothermal systems potentially economic than 30 years ago. An alternative possibility is to classify geothermal energy systems by their geologic setting. Understanding and characterizing the geologic controls on geothermal systems has been an ongoing focus on different scales from plate tectonics to local tectonics/structural geology. In fact, the geologic setting has a fundamental influence on the potential temperature, on the fluid composition, the reservoir characteristics and whether the system is a predominantly convective or conductive system. The key element in this new classification for geothermal systems is the recognition that a geothermal system is part of a geological system. The structural geological and plate tectonic setting has a fundamental influence on

  20. Geothermal energy - Energy potential under our feet; Geothermie - Energiepotenzial unter unseren Fuessen. Neue Ansaetze zur Nutzungsoptimierung

    Energy Technology Data Exchange (ETDEWEB)

    Heinzelmann, E. [CST Communication, Science and Technology GmbH, Bern (Switzerland)

    2010-07-01

    This article reviews new approaches to optimising the use of geothermal energy resources. Switzerland is quoted as being world leader in research into the use of geothermal resources. Work being done at the Swiss Federal Institutes of Technology in Zurich and Lausanne is reviewed. This includes research into the better use of energy-relevant geological structures. This work includes the simulation of thermo-mechanical behaviour and work done on reducing the costs involved in the construction of boreholes for geothermal installations. Uncertainties encountered are discussed and a pilot installation in Lausanne is described which used heat-exchanger piles for foundations. The results obtained are discussed. Also, various tests carried out in the rest of Europe are discussed. A method for the splintering of bedrock is described.

  1. Agribusiness geothermal energy utilization potential of Klamath and Western Snake River Basins, Oregon. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Lienau, P.J.

    1978-03-01

    Resource assessment and methods of direct utilization for existing and prospective food processing plants have been determined in two geothermal resource areas in Oregon. Ore-Ida Foods, Inc. and Amalgamated Sugar Company in the Snake River Basin; Western Polymer Corporation (potato starch extraction) and three prospective industries--vegetable dehydration, alfalfa drying and greenhouses--in the Klamath Basin have been analyzed for direct utilization of geothermal fluids. Existing geologic knowledge has been integrated to indicate locations, depth, quality, and estimated productivity of the geothermal reservoirs. Energy-economic needs and balances, along with cost and energy savings associated with field development, delivery systems, in-plant applications and fluid disposal have been calculated for interested industrial representatives.

  2. Potential of hybrid geothermal/coal fired power plants in Arizona

    Energy Technology Data Exchange (ETDEWEB)

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

    1982-08-01

    The City of Burbank and the Ralph M. Parsons Company studies showed several advantages for hybrid geothermal/coal fired power plants, as follows: (1) the estimated cost of producing electricity in hybrid plant is about 18.3 mills/kWh, compared to 19.3 mills/kWh in an all-coal fired power plant; (2) the coal requirements for a given plant can be reduced about 12 to 17%; and (3) the geothermal brines can be used for power plant cooling water, and in some cases, as boiler feedwater. The pertinent results of the City of Burbank studies are summarized and applied to the geothermal and coal resources of Arizona for possible future utilization.

  3. Potential interest areas for the development of geothermal energy in La Reunion Island

    OpenAIRE

    Dezayes, Chrystel; BALTASSAT, Jean-Michel; Famin, Vincent; Bès de Berc, Séverine

    2016-01-01

    International audience; La Réunion Island was always considered as a high interest for the geothermal exploitation and several exploration surveys were performed since the 70's. However, at the present day, no geothermal exploitation has been built. Nevertheless, the French environmental law, Grenelle de l'Environnement, has set ambitious goals for the French overseas territories and La Réunion must be self-powered by 2030. In this framework, BRGM and the Geoscience Laboratory of La Réunion U...

  4. GEOTHERMAL GREENHOUSING IN TURKEY

    Directory of Open Access Journals (Sweden)

    Sedat Karaman

    2016-07-01

    Full Text Available Use of renewable energy resources should be brought forward to reduce heating costs of greenhouses and to minimize the use of ever-depleting fossil fuels. Geothermal energy not only provides the heat required throughout plant growth, but also allow a year-long production. Geothermal resources with several other benefits therefore play significant role in agricultural activities. With regard to geothermal potential and implementation, Turkey has the 7th place in the world and the 1st place in Europe. Majority of country geothermal resources is used in greenhouse heating. The size of geothermal greenhouses increased 5 folds during the last decade and reached to 2500 decare. In this study, current status of geothermal greenhousing of Turkey was presented; problems and possible solutions were discussed.

  5. The geothermal power organization

    Energy Technology Data Exchange (ETDEWEB)

    Scholl, K.L. [National Renewable Energy Lab., Golden, CO (United States)

    1997-12-31

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

  6. Assessment of the origin and geothermal potential of the thermal waters by hydro-isotope geochemistry: Eskisehir province, Turkey.

    Science.gov (United States)

    Yuce, Galip; Italiano, Francesco; Yasin, Didem; Taskiran, Lutfi; Gulbay, Ahmet Hilmi

    2017-05-01

    The thermal fluids vented over Eskisehir province have been investigated for their origin and to estimate the geothermal potential of the area. Thermal waters as well as bubbling and dissolved gases were collected and analysed for their chemical and isotopic features. Their isotopic composition varies in the range from -11.5 to -7.7 ‰ for δ(18)O, -84 and -57 ‰ for δ(2)H, and 0-7.2 TU for tritium. The gases (bubbling and dissolved) are mostly N2-dominated with a significant amount of CO2. The helium isotopic ratios are in the range of 0.2-0.66 R/Rac, indicate remarkable mantle-He contribution ranging between 2 and 10 % in the whole study area. Considering the estimated geothermal gradient about three times higher than the normal gradient, and the reservoir temperatures estimated to be between 50 and 100 °C using quartz and chalcedony geothermometers, a circulation model was built where possible mixing with shallow waters cool down the uprising geothermal fluids.

  7. Deep Geothermal energy potential in Madrid basin; Potencial de la Geotermia profunda en la Cuenca de Madrid

    Energy Technology Data Exchange (ETDEWEB)

    Hidalgo, R.; Sanchez, J.; Ungemach, P.

    2009-07-01

    The Madrid Basin geothermal potential was evidenced in 1980 thanks to an oil exploration well drilled by Shell-Campsa which showed temperatures of 88 degree centigrade and 150 degree centigrade at 1,700 mts and 3,400 mts depth respectively. The low enthalpy geothermal reservoir could be further assessed by four exploratory wells the first one, Pradillo (originals Shell-Campsa oil well), two drilled by ADARO and IGME (Geological survey of Spain) in San Sebastian de los Reyes and Tres Cantos respectively. The latest well, Geomadrid 1, was drilled in 1990 by the Madrid Regional government. The afore mentioned wells have identified a dependable geothermal resource, hosted in a tertiary, clastic, consolidated sandstone reservoir consisting of a thick multilayered sequence (200-800m), with temperatures ranging from 70 degree centigrade to 90 degree centigrade and depths of 1,500 to 2,150 m., overlying a Mesozoic sequence, suitable to be exploited for thermal uses in several district heating grids around Madrid in areas displaying adequate heat loads. A medium temperature reservoir was also identified at the contact between Mesozoic Cretaceous limestones and fractured basement granites at 3,400mts depth, with measured temperatures of 156 degree centigrade, that could be developed and exploited in view of a combined power and heat production (CPH) within the Madrid suburban areas. (Author) 7 refs.

  8. Matter and Methods at Low Temperatures

    CERN Document Server

    Pobell, F

    2007-01-01

    Matter and Methods at Low Temperatures contains a wealth of information essential for successful experiments at low temperatures, which makes it suitable as a reference and textbook. The first chapters describe the low-temperature properties of liquid and solid matter, including liquid helium. The major part of the book is devoted to refrigeration techniques and the physics on which they rely, the definition of temperature, thermometry, and a variety of design and construction techniques. The lively style and practical basis of this text make it easy to read and particularly useful to anyone beginning research in low-temperature physics. Low-temperature scientists will find it of great value due to its extensive compilation of materials data and relevant new results on refrigeration, thermometry, and materials properties. Problems are included as well. Furthermore, this third edition also describes newly developed low-temperature experimentation techniques and new materials properties; it also contains many a...

  9. Preparation of silver nanoparticles at low temperature

    Science.gov (United States)

    Mishra, Mini; Chauhan, Pratima

    2016-04-01

    Silver from ancient time is used as antimicrobial agent in the bulk form but now with the advancement in nanotechnology silver in the form of nanoparticles shown potential effect against microbes which make us easy to fight with many diseases plants and animals. In this work silver nanoparticles were synthesized by chemical routes using sodium borohydride as reducing agent at low temperature. The particles were characterized through UV-Visible spectroscopy as well as X-Ray Diffraction. The UV-visible spectra of silver nanoparticles exhibited absorption at 425 cm; the crystallite size of the particles is between 19nm to 39nm. EDAX graph shows two peaks of silver and oxygen. Water absorbed by silver nanoparticles was removed by the calcinations.

  10. Preparation of silver nanoparticles at low temperature

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, Mini, E-mail: mishramini5@gmail.com [Centre of Environmental Science, Department of Botany, University of Allahabad, Allahabad, U.P. (India); Chauhan, Pratima, E-mail: mangu167@yahoo.co.in [Department of Physics, University of Allahabad, Allahabad U.P. (India)

    2016-04-13

    Silver from ancient time is used as antimicrobial agent in the bulk form but now with the advancement in nanotechnology silver in the form of nanoparticles shown potential effect against microbes which make us easy to fight with many diseases plants and animals. In this work silver nanoparticles were synthesized by chemical routes using sodium borohydride as reducing agent at low temperature. The particles were characterized through UV-Visible spectroscopy as well as X-Ray Diffraction. The UV-visible spectra of silver nanoparticles exhibited absorption at 425 cm; the crystallite size of the particles is between 19nm to 39nm. EDAX graph shows two peaks of silver and oxygen. Water absorbed by silver nanoparticles was removed by the calcinations.

  11. Reappraisal of the geothermal potential at Colli Albani volcano (Italy): a new approach to the volume method

    Science.gov (United States)

    Giordano, G.; De Benedetti, A. A.; Ramazzotti, P.; Bonamico, A.; Mattei, M.

    2012-04-01

    High enthalpy geothermal reservoirs are usually associated with fractured rocks. Secondary permeability is however difficult to be predicted thus making it difficult to locate the most productive volumes of the reservoirs. The calculation of the energetic potential in geothermal areas suffers of the large uncertainties associated with secondary permeability issues, facing the task of the interplay between stratification and fracturing on the anisotropic distribution of secondary permeability. The object of this work is the research and informatization of available data for the Colli Albani (Latium, Central Italy) geothermal system, in order to propose a qualitative approach and quantitative identification and description of geothermal systems, applied to the Colli Albani area as a case history. The identification of the rock volumes most promising in terms of industrial exploitation needs the definition of an evaluation matrix. The considered data can be placed in a three dimensional matrix with A axis that accounts for the modeling of the depth of the top of the reservoirs based on geophysical and direct data, and a B axis that accounts for the thermal modeling of the crust (i.e. T with depth) based on measured thermal gradients. Both A and B data are strongly influenced by the geological model therefore, as for the case of Colli Albani, there is certainly a lot of scope into revising existing geological reconstructions of the reservoirs in Central Italy and accordingly reconsidering the interpolation and modeling of both thermal and geophysical data. For the scope of this work, we have taken into account the maps descriptive the thermal structure and the deep distribution of the top of the geothermal reservoirs produced by ENEL and AGIP between the 1970s and 1990s for Cental Italy, and we have detailed the internal structure of the substrate, considering more recent direct and indirect data on the nature of the substratum. Finally, we discuss the implementation

  12. Electricity from geothermal energy: Costs and cost reduction potentials; Strom aus Geothermie. Kosten und Kostensenkungspotenziale

    Energy Technology Data Exchange (ETDEWEB)

    Koelbel, Thomas; Eggeling, Lena [EnBW Energie Baden-Wuerttemberg AG, Karlsruhe (Germany). Forschung und Innovation; Kruck, Christoph [Stuttgart Univ. (DE). Inst. fuer Energiewirtschaft und Rationelle Energieanwendung (IER); Weimann, Thorsten [gec-co Global Engineering and Consulting-Company GmbH, Augsburg (Germany)

    2012-07-01

    The use of geothermal energy for power generation in low-enthalpy devices is a young technology. The first German plant was taken in operation in 2004 at Neustadt-Glewe (Federal Republic of Germany). Three more plants came up by the end of 2009. Although the demonstration stage just was left, investigations provided prime costs similar to those of other renewable energies.

  13. Potential Distribution of Geothermal Resource in Western Region of Daqing Placanticline%大庆长垣西部地区地热资源潜力分布

    Institute of Scientific and Technical Information of China (English)

    翟志伟; 施尚明; 朱焕来

    2011-01-01

    Geothermal resource is a clean and renewable new energy. The western region of Daqing Placantieline is located the high geothermal gradient region in Songliao Basin, and belong typical medium-low temperature geothermal resource of sedimentary basin. As affected with shallow depth of Moho surface and developmental deep fault rupture in this region, the temperature of middle oil and gas-bearing reservoirs is great higher. By composite evaluation of each reservoir petrophysical and geotemperature field properties, three types geothermal reservoirs are divided and their control reserves are estimated, which guides reasonable exploitation and utilization of geothermal resource effectively, and then acquires obvious economic and social benefits.%地热资源是一种清洁的、可再生的新能源.大庆长垣西部地区地处松辽盆地地温梯度的高值构造带,属于典型的沉积盆地型中低温地热资源.该区地温场受到莫霍面埋深浅、深大断裂发育等因素的影响,中部含油气组合等热储层温度较高,通过对各个热储的物性特征以及地温特征进行综合评价,将研究区划分为了三类热储,并估算了控制资源量,有效地指导地热资源的合理开发利用,取得了明显的经济效益和社会效益.

  14. Geothermal potential of northern Bavaria: Analysis of geothermal resources by evaluation of geophysical temperature logs in drinking water wells and deep wells; Geothermisches Potential Nordbayerns - Untersuchungen der geothermischen Verhaeltnisse durch Auswertung geophysikalischer Temperaturmessungen in Trinkwasser- und Tiefbohrungen

    Energy Technology Data Exchange (ETDEWEB)

    Bauer, W.; Udluft, P. [Lehr- und Forschungsbereich Hydrogeologie und Umwelt, Inst. fuer Geologie, Wuerzburg Univ. (Germany)

    1997-12-01

    The geothermal potential of northern Bavaria was investigated. Thermal water in the lower heat range may be used, e.g., for space heating, bath heating and agricultural purposes. Geophysical data were obtained from a number of drinking water wells with a depth of less than 150 m and a few deep wells of more than 150 m. The data are to serve as a decision aid for potential users of geothermal energy and reduce the exploration risk. (orig.) [Deutsch] Zielsetzung des Forschungsvorhabens ist die Bewertung des geothermischen Potentials Nordbayerns im Hinblick auf die Nutzung von Tiefenwasser zur Gewinnung von hydrothermaler Energie. Niedrigthermale Tiefenwaesser bieten sich z.B. als Energietraeger fuer Raumwaerme, Baederheizung and landwirtschaftliche Nutzung an. Die geothermischen Daten liegen in Form von geophysikalischen Temperaturmessungen aus zahlreichen Trinkwasserbohrungen mit weniger als 150 m Bohrtiefe und einigen Tiefbohrungen mit mehr als 150 m Bohrtiefe vor. Die Bewertung des geothermischen Potentials Nordbayerns soll als Planungsgrundlage fuer potentialle Erdwaermenutzer dienen und zu einer Minimierung des Explorationsrisikos beitragen. (orig.)

  15. Low temperature rate coefficients of the H + CH{sup +} → C{sup +} + H{sub 2} reaction: New potential energy surface and time-independent quantum scattering

    Energy Technology Data Exchange (ETDEWEB)

    Werfelli, Ghofran [Université de Bordeaux, Institut des Sciences Moléculaires, CNRS UMR 5255, 33405 Talence Cedex (France); Faculté des Sciences de Tunis, Université de Tunis El-Manar, Laboratoire de Physique de la Matière Condensée, 2092 Tunis (Tunisia); Halvick, Philippe; Stoecklin, Thierry [Université de Bordeaux, Institut des Sciences Moléculaires, CNRS UMR 5255, 33405 Talence Cedex (France); Honvault, Pascal [Université de Bourgogne Franche-Comté, Laboratoire Interdisciplinaire Carnot de Bourgogne, CNRS UMR 6303, 21078 Dijon Cedex (France); Université de Franche-Comté, UFR ST, 25030 Besançon Cedex (France); Kerkeni, Boutheïna [Faculté des Sciences de Tunis, Université de Tunis El-Manar, Laboratoire de Physique de la Matière Condensée, 2092 Tunis (Tunisia); Institut Supérieur des Arts Multimédia de la Manouba, Université de la Manouba, 2010 la Manouba (Tunisia)

    2015-09-21

    The observed abundances of the methylidyne cation, CH{sup +}, in diffuse molecular clouds can be two orders of magnitude higher than the prediction of the standard gas-phase models which, in turn, predict rather well the abundances of neutral CH. It is therefore necessary to investigate all the possible formation and destruction processes of CH{sup +} in the interstellar medium with the most abundant species H, H{sub 2}, and e{sup −}. In this work, we address the destruction process of CH{sup +} by hydrogen abstraction. We report a new calculation of the low temperature rate coefficients for the abstraction reaction, using accurate time-independent quantum scattering and a new high-level ab initio global potential energy surface including a realistic model of the long-range interaction between the reactants H and CH{sup +}. The calculated thermal rate coefficient is in good agreement with the experimental data in the range 50 K–800 K. However, at lower temperatures, the experimental rate coefficient takes exceedingly small values which are not reproduced by the calculated rate coefficient. Instead, the latter rate coefficient is close to the one given by the Langevin capture model, as expected for a reaction involving an ion and a neutral species. Several recent theoretical works have reported a seemingly good agreement with the experiment below 50 K, but an analysis of these works show that they are based on potential energy surfaces with incorrect long-range behavior. The experimental results were explained by a loss of reactivity of the lowest rotational states of the reactant; however, the quantum scattering calculations show the opposite, namely, a reactivity enhancement with rotational excitation.

  16. Revision, calibration, and application of the volume method to evaluate the geothermal potential of some recent volcanic areas of Latium, Italy

    Energy Technology Data Exchange (ETDEWEB)

    Doveri, Marco; Lelli, Matteo; Raco, Brunella [Institute of Geosciences and Georesources, CNR, Area della Ricerca, Via G. Moruzzi 1, I-56124 Pisa (Italy); Marini, Luigi [Laboratory of Geochemistry, Dip.Te.Ris., University of Genova, Corso Europa 26, I-16132 Genova (Italy); Institute of Geosciences and Georesources, CNR, Area della Ricerca, Via G. Moruzzi 1, I-56124 Pisa (Italy)

    2010-09-15

    The volume method is used to evaluate the productive potential of unexploited and minimally exploited geothermal fields. The distribution of P{sub CO2} in shallow groundwaters delimits the geothermal fields. This approach is substantiated by the good correspondence between zones of high CO{sub 2} flux, and the areal extension of explored geothermal systems of high enthalpy (Monte Amiata and Latera), medium enthalpy (Torre Alfina) and low enthalpy (Viterbo). Based on the data available for geothermal fields either under exploitation or investigated by long-term production tests, a specific productivity of 40 t h{sup -1} km{sup -3} is assumed. The total potential productivity for the recent volcanic areas of Latium is about 28 x 10{sup 3} t h{sup -1}, with 75% from low-enthalpy geothermal fields, 17% from medium-enthalpy systems, and 8% from high-enthalpy reservoirs. The total extractable thermal power is estimated to be 2220-2920 MW, 49-53% from low-enthalpy geothermal fields, 28-32% from medium-enthalpy systems, and 19-20% from high-enthalpy reservoirs. (author)

  17. Geothermal direct-heat utilization assistance. Quarterly project progress report, July 1995--September 1995

    Energy Technology Data Exchange (ETDEWEB)

    Lienau, P.

    1995-12-01

    The report summarizes geothermal technical assistance, R&D and technology transfer activities of the Geo-Heat Center at Oregon Institute of Technology for the fourth quarter of FY-95. It describes 80 contacts with parties during this period related to technical assistance with geothermal direct heat projects. Areas dealt with include geothermal heat pumps, space heating, greenhouses, aquaculture, equipment and resources. Research activities are summarized on low-temperature resource assessment, geothermal energy cost evaluation and marketing strategy for geothermal district heating. Outreach activities include the publication of a geothermal direct use Bulletin, dissemination of information, geothermal library, technical papers and seminars, and progress monitor reports on geothermal resources and utilization.

  18. Geothermal resource evaluation of the Yuma area

    Energy Technology Data Exchange (ETDEWEB)

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

    1985-11-29

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

  19. Utilization of low temperature heat for environmentally friendly electricity production

    DEFF Research Database (Denmark)

    Andreasen, Jesper Graa; Elmegaard, Brian; Haglind, Fredrik

    2014-01-01

    The focus on reduction of fossil fuelled electricity generation has increased the attention on exploitation of low grade heat as the energy source for electricity producing power plants. Low grade heat is heat, which isavailable at a low temperature, e.g. from waste heat from marine diesel engines...... and industrial processes orfrom geothermal and solar heat sources. Utilization of such heat sources makes it possible to produce electricity with no additional burning of fossil fuel, and does therefore represent an environmentally friendly alternative to fossil fuel based electricity production. Utilization...... of low grade heat is not feasible with conventional steam Rankine cycles (steam engines) due to undesirable properties of steam. Instead the organic Rankine cycle is typically used, since it enables thechoice of a working fluid, e.g. hydrocarbons or refrigerants, with desirable properties. One of the key...

  20. Low Temperature District Heating for Future Energy Systems

    DEFF Research Database (Denmark)

    Schmidt, Dietrich; Kallert, Anna; Blesl, Markus

    2017-01-01

    of the building stock. Low temperature district heating (LTDH) can contribute significantly to a more efficient use of energy resources as well as better integration of renewable energy (e.g. geothermal or solar heat), and surplus heat (e.g. industrial waste heat) into the heating sector. LTDH offers prospects......, such as combustible fuels, and minimising energy losses and irreversible dissipation. The paper presents the international co-operative work in the framework of the International Energy Agency (IEA), the Technology Cooperation Programme on District Heating and Cooling including Combined Heat and Power (DHC|CHP) Annex......The building sector is responsible for more than one third of the final energy consumption of societies and produces the largest amount of greenhouse gas emissions of all sectors. This is due to the utilisation of combustion processes of mainly fossil fuels to satisfy the heating demand...

  1. Low Temperature Induced Conformation Changes of Aminoacylase

    Institute of Scientific and Technical Information of China (English)

    谢强; 孟凡国; 周海梦

    2004-01-01

    Control of aggregation, by lowering temperature and protein concentrations, can enhance the extent of successful refolding. The low temperature has been used in protein folding studies, as undesired aggregations often occur at higher temperatures. Therefore, it is very important to study the effects of low temperature on the native enzyme to help understand the factors that affect the structure of the proteins. In this paper, aminoacylase was studied at different temperatures by measuring enzyme activity, fluorescence emission spectra, and ultraviolet difference spectra. The results show that aminoacylase conformation changes as the temperature changes, becoming more compact at low temperatures, and having more secondary structural content. However, the activity is very low at low temperature, and totally diminishes at 4℃. Aminoacylase tends therefore to be more condense, with less residues exposed and low enzyme activities at low temperature. This observation might explain the self-protection of organisms under conditions of extreme temperature.

  2. Hydrochemical and isotopic (2H, 18O and 37Cl) constraints on evolution of geothermal water in coastal plain of Southwestern Guangdong Province, China

    Science.gov (United States)

    Chen, Liuzhu; Ma, Teng; Du, Yao; Xiao, Cong; Chen, Xinming; Liu, Cunfu; Wang, Yanxin

    2016-05-01

    dissolved Cl- in geothermal water. Estimated reservoir temperatures show that geothermal reservoirs in study area are mid-low temperature geothermal reservoirs.

  3. Geophysical Investigations to Assess Geothermal Energy Potential, Socorro Peak, New Mexico

    Science.gov (United States)

    Tobin, H. J.; Baars, R. M.; Norman, D.; Owens, L.; Cumming, W.

    2005-12-01

    The Socorro Peak uplift in central New Mexico has long been known to host a strongly localized heat flow anomaly. Shallow thermal gradient wells show heat flows as high as 490 mW/m2 at depths to ~100 m, superimposed on background values of 60-80 mW/m2. Warm springs at the south end of the mountain block produce water of ~ 35 C, and show chemical evidence of thermal water highly diluted by shallow groundwater. Recently, interest has grown in assessing the potential for direct use of these thermal waters for space heating of buildings on the New Mexico Institute of Mining and Technology campus. We have therefore undertaken multidisciplinary exploration efforts in order to better understand the structure and hydrogeology of the hydrothermal system, and to site a planned 1000 m exploratory well. In particular, we have collected high-resolution magnetotelluric profile data at 100 m station spacing to characterize the near surface distribution of conductivity across the range bounding fault on the east side of the Socorro Peak uplift, where the geothermal gradients are highest. Two dimensional inversions of the data, constrained by known local geology, show that a single fault, corresponding to the mapped main fault, is the locus of major displacement for at least the upper 1000 m, juxtaposing footwall preCambrian and Paleozoic rocks and Tertiary volcaniclastics against hanging wall alluvial sediments of the Rio Grande Rift. We tentatively identify an imaged conductive zone at depths of 400 m or more below surface east of the fault as a regional aquitard separating the shallow groundwater from underlying possible hydrothermal systems, structurally juxtaposed with a moderately resistive block in the footwall. A synthesis of geophysical and geologic evidence for the architecture of this hydrothermal system places these units in fault contact at a strongly fractured intersection of the Socorro Canyon fault with the older ring fracture of the Socorro caldera, accompanied by

  4. Outdoor recreational use of the Salton Sea with reference to potential impacts of geothermal development

    Energy Technology Data Exchange (ETDEWEB)

    Twiss, R.; Sidener, J.; Bingham, G.; Burke, J.E.

    1978-04-01

    The objectives of this study were to describe the types, levels, and locations of outdoor recreation uses in the Salton Sea area, the number and principal activities of visitors, and to estimate the consequences upon outdoor recreation of geothermal development and other activities that might affect the Salton Sea. It is concluded that since the Salton Sea is considered legally to be a sump for agricultural, municipal, and presumably geothermal waste waters, recreational use of the Sea for fishing and boating (from present marinas) will undoubtedly continue to decline, unless there is a major policy change. Use of the shoreline for camping, the surrounding roads and lands for scenic viewing, ORV events, and retirement or recreation communities will not decline, and will probably increase, assuming control of hydrogen sulfide odors. Two ways in which the fishing and present boating facilities could be returned to a wholly usable steady state are discussed. One is by construction of a diked evaporation pond system at the south end of the Sea. This would allow a means of control over both water level and salinity. Another means, less costly but more difficult to effectively control, would be to budget geothermal plant use of, and disposal of wastes in, Salton Sea water. (JGB)

  5. Reservoir stratum characterstics and geothermal resources potential of Rongcheng uplift geothermal field in Baoding, Hebei%河北保定容城凸起地热田储层属性与资源潜力

    Institute of Scientific and Technical Information of China (English)

    郭世炎; 李小军

    2013-01-01

    21世纪人类将面临资源、环境与灾害的严重挑战.地热资源作为绿色新型能源,可减少传统燃料的消耗,实现CO2减排,日益受到人们的青睐.河北保定市容城凸起地热田为我国东部代表性中低温地热田,其热储类型为基岩岩溶裂隙热储(主要为蓟县系雾迷山组及长城系高于庄组),具有储量大,可回灌等特点.根据现有数据和地质资料进行的地热资源潜力评估表明:容城凸起(56 km2研究区范围)基岩(3000 m以浅)热储地热资源量为416×1016J,相当于标准煤239×106t,折合热能1320 MW;可采地热资源量为62×1016 J,相当于标准煤36×106 t,折合热能198 MW.%The severe challenges for mankind in the 21st century are resource,environment,and disaster.Geothermal resource,as a green new energy,which could reduce the consumption of traditional fuels and implement the emission reduction of CO2,are becoming increasingly popular.Rongcheng Uplift geothermal field in Baoding,Hebei province is a typical low-medium temperature geothermal field in eastern China,and its geothermal reservoir is bedrock karstfissure of Middle Proterozoic Wumishan group Jxw and Gaoyuzhuang group Chg,and characterized by large water reserves and rechargeable reservior.Evaluation of the geothermal resource potential based on the existing data and geological information indicates:the geothermal reservoir of Rongcheng uplift (56 km2 in the study area) bedrock (shallower than 3000 m)has a total of 416×1016 J geothermal resource,equivalent to 239×106 t standard coal,which can convert to 1320 MW of heat.The estimated exploitable geothermal resource is 62×1016 J,equivalent to 36×106 t standard coal,or 198 MW heat.

  6. IRETHERM: Magnetotelluric Assessment of Geothermal Energy Potential of Hydrothermal Aquifer, Radiothermal Granite and Warm Spring Targets in Ireland

    Science.gov (United States)

    Jones, Alan G.; Muller, Mark; Fullea, Javier; Vozar, Jan; Blake, Sarah; Delhaye, Robert; Farrell, Thomas

    2013-04-01

    IRETHERM (www.iretherm.ie) is an academic-government-industry, collaborative research project, funded by Science Foundation Ireland, with the overarching objective of developing a holistic understanding of Ireland's low-enthalpy geothermal energy potential through integrated modelling of new and existing geophysical and geological data. With the exception of Permo-Triassic basins in Northern Ireland, hosting geothermal aquifers of promising but currently poorly-defined potential, rocks with high primary porosity have not been identified elsewhere. Whether any major Irish shear zones/faults might host a geothermal aquifer at depth is also unknown, although clusters of warm-springs in the vicinity of two major shear zones are promising. IRETHERM's objectives over a four-year period are to: (i) Develop multi-parameter geophysical modelling and interpretation software tools that will enhance our ability to explore for and assess deep aquifers and granitic intrusions. (ii) Model and understand temperature variations in the upper-crust. Firstly, by building a 3-D model of crustal heat-production based on geochemical analysis of surface, borehole and mid- to lower-crustal xenolith samples. Secondly, by modelling, using a fully self-consistent 3-D approach, observed surface heat-flow variation as a function of variation in the structure and thermal properties of the crust and lithosphere, additionally constrained by surface elevation, geoid, gravity, seismic and magnetotelluric (MT) data. (iii) Test a strategic set of eight "type" geothermal targets with a systematic program of electromagnetic surveys (MT, CSEM) across ten target areas. During 2012, IRETHERM collected over 220 MT/AMT sites in the investigation of a range of different geothermal target types. Here we present preliminary electrical resistivity modelling results for each target investigated and discuss the implications of the models for geothermal energy potential: 1. Rathlin Basin The only sedimentary strata

  7. Modeling self-potential data in the Abraham and Meadow-Hatton geothermal systems: The search for upflow zones

    Energy Technology Data Exchange (ETDEWEB)

    Schima, S.; Wilt, M. [Lawrence Livermore National Lab., CA (United States); Ross, H. [Utah Univ. Research Inst., Salt Lake City, UT (United States)

    1995-07-01

    Computer code SPXCL is a finite difference modeling algorithm that calculates the response of embedded point sources within a rectangular, two-dimensional medium. The code calculates the electrical potential anywhere in the medium from thermal or pressure sources. This code is useful in calculating self-potential measurements that may be used to locate upflow zones in geothermal systems. Beginning in 1991 data on self-potential was collected at Abraham and Meadow-Hatton Hot Springs, two of the largest thermal spring systems in Utah. In this paper, these data were modeled to determine upflow zones and source characteristics using the SPXCL code. The forward solution for fluid and heat flow models and the resulting self-potential anomalies were calculated.

  8. Low-Temperature Power Electronics Program

    Science.gov (United States)

    Patterson, Richard L.; Dickman, John E.; Hammoud, Ahmad; Gerber, Scott

    1997-01-01

    Many space and some terrestrial applications would benefit from the availability of low-temperature electronics. Exploration missions to the outer planets, Earth-orbiting and deep-space probes, and communications satellites are examples of space applications which operate in low-temperature environments. Space probes deployed near Pluto must operate in temperatures as low as -229 C. Figure 1 depicts the average temperature of a space probe warmed by the sun for various locations throughout the solar system. Terrestrial applications where components and systems must operate in low-temperature environments include cryogenic instrumentation, superconducting magnetic energy storage, magnetic levitation transportation system, and arctic exploration. The development of electrical power systems capable of extremely low-temperature operation represents a key element of some advanced space power systems. The Low-Temperature Power Electronics Program at NASA Lewis Research Center focuses on the design, fabrication, and characterization of low-temperature power systems and the development of supporting technologies for low-temperature operations such as dielectric and insulating materials, power components, optoelectronic components, and packaging and integration of devices, components, and systems.

  9. [Low temperature plasma technology for biomass refinery].

    Science.gov (United States)

    Fu, Xiaoguo; Chen, Hongzhang

    2014-05-01

    Biorefinery that utilizes renewable biomass for production of fuels, chemicals and bio-materials has become more and more important in chemical industry. Recently, steam explosion technology, acid and alkali treatment are the main biorefinery treatment technologies. Meanwhile, low temperature plasma technology has attracted extensive attention in biomass refining process due to its unique chemical activity and high energy. We systemically summarize the research progress of low temperature plasma technology for pretreatment, sugar platflow, selective modification, liquefaction and gasification in biomass refinery. Moreover, the mechanism of low temperature plasma in biorefinery and its further development were also discussed.

  10. Low temperature nitrogen chemistry. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Glarborg, P.; Dam-Johansen, K.; Kristensen, P.G.; Alzueta, M.; Roejel, H.

    1997-04-01

    The results of a two tasks program on Natural Gas Reburning are reported. The work involved an experimental and theoretical study of the reburning and hybrid reburning/SNCR chemistry in the 1000-1500 K range. The interactions between hydrocarbon and nitrogen chemistry under fuel-rich conditions were investigated in order to assess the NO{sub x} reduction potential of low temperature reburning. The effect of reburn fuel(carbon monoxide, methane, acetylene, ethylene, ethane, and methane/ethane mixture), temperature, stoichiometry, reactant dilution, reaction time, and inlet NO level were studied. The results indicate a significant NO reduction potential even below 1400 K, but extrapolation to practical conditions are complicated by inadequate knowledge of the detailed chemistry as well as of the effect of mixing. The possibilities of enhancing the conversion to N{sub 2} instead of NO by adding selective reducing agents (hybrid reburning/SNCR) were evaluated. Our results indicate little synergistic effect between reburn and SNCR. The most simple configuration, where the selective reducing agent is injected together with the burnout air, is not expected to be effective, unless the N-agent is injected in form of an aqueous solution. A chemical kinetic model for reburning and reburn/SNCR is listed and can be obtained by e-mail from pgl(commerical at)kt.dtu.dk.(au) 145 refs.

  11. Geothermal direct heat use: market potential/penetration analysis for Federal Region IX (Arizona, California, Hawaii, Nevada)

    Energy Technology Data Exchange (ETDEWEB)

    Powell, W.; Tang, K. (eds.)

    1980-05-01

    A preliminary study was made of the potential for geothermal direct heat use in Arizona, California, Hawaii, and Nevada (Federal Region IX). The analysis for each state was performed by a different team, located in that state. For each state, the study team was asked to: (1) define the resource, based on the latest available data; (2) assess the potential market growth for geothermal energy; and (3) estimate the market penetration, projected to 2020. Each of the four states of interest in this study is unique in its own way. Rather than impose the same assumptions as to growth rates, capture rates, etc. on all of the study teams, each team was asked to use the most appropriate set of assumptions for its state. The results, therefore, should reflect the currently accepted views within each state. The four state reports comprise the main portion of this document. A brief regional overview section was prepared by the Jet Propulsion Laboratory, following completion of the state reports.

  12. Reservoir Maintenance and Development Task Report for the DOE Geothermal Technologies Office GeoVision Study.

    Energy Technology Data Exchange (ETDEWEB)

    Lowry, Thomas Stephen; Finger, John T.; Carrigan, Charles R.; Foris, Adam; Kennedy, Mack B.; Corbet, Thomas F.,; Doughty, Christine A.; Pye, Steven; Sonnenthal, Eric L.

    2017-09-01

    This report documents the key findings from the Reservoir Maintenance and Development (RM&D) Task of the U.S. Department of Energy's (DOE), Geothermal Technologies Office (GTO) Geothermal Vision Study (GeoVision Study). The GeoVision Study had the objective of conducting analyses of future geothermal growth based on sets of current and future geothermal technology developments. The RM&D Task is one of seven tasks within the GeoVision Study with the others being, Exploration and Confirmation, Potential to Penetration, Institutional Market Barriers, Environmental and Social Impacts, Thermal Applications, and Hybrid Systems. The full set of findings and the details of the GeoVision Study can be found in the final GeoVision Study report on the DOE-GTO website. As applied here, RM&D refers to the activities associated with developing, exploiting, and maintaining a known geothermal resource. It assumes that the site has already been vetted and that the resource has been evaluated to be of sufficient quality to move towards full-scale development. It also assumes that the resource is to be developed for power generation, as opposed to low-temperature or direct use applications. This document presents the key factors influencing RM&D from both a technological and operational standpoint and provides a baseline of its current state. It also looks forward to describe areas of research and development that must be pursued if the development geothermal energy is to reach its full potential.

  13. GEOTHERMICS GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    <正>20091762 Guo Wancheng(Xining Jiulong Engineering Investigation Ltd.,Xining 810700,China);Shi Xingmei Development and Utilization of Guide Basin’s Geothermal Resources of Qinghai Province(Hydrogeology and Engineering Geology,ISSN1000-3665,CN11-2202/P,35(3),2008,p.79-80,92,2 illus.,2 tables,2 refs.)Key words:geothermal resources,QinghaiThis paper introduced the background of geothermal conditions and the many years of geothermal exploration data in Guide Basin.Then,the authors discussed the geothermal resources feature of Guide basin and raised some opinions on the reasonable development and utilization of geothermal resources.

  14. Idaho Geothermal Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Hammer, Gay Davis; Esposito, Louis; Montgomery, Martin

    1979-07-01

    Idaho's energy problems have increased at alarming rates due to their dependency on imports of gas and oil. The large hydroelectric base developed in Idaho has for years kept the electric rates relatively low and supplied them with energy on a consumer demand basis. However, this resource cannot be 4expected to meet their growing demands in the years to come. Energy alternatives, in whatever form, are extremely important to the future welfare of the State of Idaho. This handbook addresses the implications, uses, requirements and regulations governing one of Idaho's most abundant resources, geothermal energy. The intent of the Idaho Geothermal Handbook is to familiarize the lay person with the basis of geothermal energy in Idaho. The potential for geothermal development in the State of Idaho is tremendous. The authors hope this handbook will both increase your knowledge of geothermal energy and speed you on your way to utilizing this renewable resource.

  15. Low temperature synthesis of porous silicate ceramics

    OpenAIRE

    Méndez Enríquez Y.; Vlasova M.; Leon I.; Kakazey M.G.; Dominguez-Patiño M.; Isaeva L.; Tomila T.

    2007-01-01

    Impregnation of a polyurethane sponge with kaolin, feldspar, silica, fusible glass slurry followed by temperature treatment in air in the temperature range 800-1000 0 C leads to the formation of aluminosilicate ceramics with a set pore size. The low-temperature synthesis of porous ceramics is based on the stage-by-stage formation of low-temperature eutectics and thermodestruction of polyurethane sponge.

  16. Low temperature synthesis of porous silicate ceramics

    Directory of Open Access Journals (Sweden)

    Méndez Enríquez Y.

    2007-01-01

    Full Text Available Impregnation of a polyurethane sponge with kaolin, feldspar, silica, fusible glass slurry followed by temperature treatment in air in the temperature range 800-1000 0 C leads to the formation of aluminosilicate ceramics with a set pore size. The low-temperature synthesis of porous ceramics is based on the stage-by-stage formation of low-temperature eutectics and thermodestruction of polyurethane sponge.

  17. Low temperature plasma technology methods and applications

    CERN Document Server

    Chu, Paul K

    2013-01-01

    Written by a team of pioneering scientists from around the world, Low Temperature Plasma Technology: Methods and Applications brings together recent technological advances and research in the rapidly growing field of low temperature plasmas. The book provides a comprehensive overview of related phenomena such as plasma bullets, plasma penetration into biofilms, discharge-mode transition of atmospheric pressure plasmas, and self-organization of microdischarges. It describes relevant technology and diagnostics, including nanosecond pulsed discharge, cavity ringdown spectroscopy, and laser-induce

  18. Cold-active and NaCl-tolerant exo-inulinase from a cold-adapted Arthrobacter sp. MN8 and its potential for use in the production of fructose at low temperatures.

    Science.gov (United States)

    Zhou, Junpei; Lu, Qian; Peng, Mozhen; Zhang, Rui; Mo, Minghe; Tang, Xianghua; Li, Junjun; Xu, Bo; Ding, Junmei; Huang, Zunxi

    2015-03-01

    An exo-inulinase gene was cloned from Arthrobacter sp. MN8, a cold-adapted bacterium isolated from lead-zinc-rich soil. The gene was expressed in Escherichia coli BL21(DE3). The resultant 505-residue polypeptide (InuAMN8) showed the highest identity (81.1%) with the putative levanase from Arthrobacter phenanthrenivorans Sphe3 (ADX73279) and shared 57.8% identity with the exo-inulinase from Bacillus sp. snu-7 (AAK00768). The purified recombinant InuAMN8 (rInuAMN8) showed an apparently optimal activity at 35°C, and 75.3%, 39.4%, and 15.8% of its maximum activity at 20°C, 10°C, and 0°C, respectively. After pre-incubation for 60 min at 50°C and 55°C, the rInuAMN8 exhibited 69.8% and 17.7% of its initial activity, respectively. The apparent Km values of rInuAMN8 towards inulin were 2.8, 1.5, 1.2, 5.3, and 8.2 mM at 0°C, 10°C, 20°C, 30°C, and 35°C, respectively. Inulin and Jerusalem artichoke tubers were effectively hydrolyzed to release fructose by rInuAMN8 at 0°C, 10°C, and 35°C. Compared with its hyperthermophilic and thermophilic counterparts, the exo-inulinase had less aromatic amino acid F and more hydrophobic amino acid A. In addition, the purified rInuAMN8 retained 127.9%-88.4% inulinase activity at 3.5%-15.0% (w/v) NaCl concentrations. Zn(2+) and Pb(2+) at 10 mM exhibited little or no effect on the enzyme activity. This paper is the first to report a cold-active and/or NaCl-tolerant exo-inulinase from the genus Arthrobacter. The exo-inulinase rInuAMN8 shows a potential for use in the production of fructose at low temperatures. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  19. Development of geothermal field following the 2000 eruption of Usu volcano as revealed by ground temperature, resistivity and self-potential variations

    Directory of Open Access Journals (Sweden)

    T. Mogi

    2007-06-01

    Full Text Available The 2000 eruption of Usu volcano, NE Japan, took place on the foot of the somma, and formed a cryptodome of 65 m high accompanying numerous faults. We made repeated measurements of ground temperature, Self-Potential (SP and electrical resistivity, in order to clarify the mechanism of development of the newly formed geothermal field on the fault zone. Prior to the expansion of the geothermal field, we detected a resistive zone at the center of the geothermal zone and it supposed to evidence that the zone involving dry steam phase had been formed beneath the fault zone. A rapid expansion of the geothermal field followed along the fault zone away from the craters. The place of maximum amplitude of the SP field also migrated following the expansion of the high ground temperature zone. The high resistive part has shrunk as a consequence of the progress of condensation to warm the surroundings. Based on the observations, we delineated the process of the hydrothermal circulation. Considering the topographic effect of the SP field observed on the highly permeable zone in the Usu somma, the potential flow along the slope of the soma was expected to play an important role to promote the rapid expansion of the geothermal field and the migration of the most active part.

  20. Earthquake, strong tide and global low temperature

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    "La Madre" is a kind of upper atmospheric air current, and occurs as "warm phase" and "cold phase" in the sky of Pacific Ocean alternately. There exists this phenomenon, called "Oscillation Decade in the Pacific" (ODP), for 20~30years. It is concerned with 60 year cycle of the tides. Lunar oscillations explain an intriguing 60-year cycle in the world's temperature. Strong tides increase the vertical mixing of water in the oceans, drawing cold ocean water from the depths to surface, where it cools the atmosphere above. The first strong seismic episode in China was from 1897 to 1912; the second to the fifth was the in1920-1937, 1946-1957, 1966-1980, 1991-2002, tsrectruely. The alternative boundaries of"La Madre" warm phase and cold phase were in 1890, 1924, 1946 and 2000, which were near the boundaries of four strong earthquakes. It indicated the strong earthquakes closedly related with the substances' motion of atmosphere, hydrosphere and lithosphere, the change of gravity potential, and the exchange of angular momentum. The strong earthquakes in the ocean bottom can bring the cool waters at the deep ocean up to the ocean surface and make the global climate cold. the earthquake, strong tide and global low temperature are close inrelntion for each othen.

  1. Geothermal Power Technologies

    DEFF Research Database (Denmark)

    Montagud, Maria E. Mondejar; Chamorro, C.R.

    2016-01-01

    Although geothermal energy has been widely deployed for direct use in locations with especial geologic manifestations, its potential for power generation has been traditionally underestimated. Recent technology developments in drilling techniques and power conversion technologies from low...

  2. Geothermal Energy

    Energy Technology Data Exchange (ETDEWEB)

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

    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.

  3. Preliminary assessment of the geothermal resource potential of the Yuma area, Arizona

    Energy Technology Data Exchange (ETDEWEB)

    Stone, C.

    1981-01-01

    The Yuma area has had a long and complex tectonic history. The most southwesterly corner of the area presently comprises a small segment of the Salton Trough, a deep sediment-filled structural depression. Known geothermal anomalies in the Salton Trough make the Yuma area a favorable exploration target even though spreading-center heat sources are not expected to occur there. Geological and geophysical investigations reveal that the area is made up of low, rugged northwest-trending mountains separated by deep sediment-filled basins. Relief is a result of both erosional and structural activity. Northwest-trending en-echelon faults bound the range fronts and the basins, and have created several horst blocks (basement highs) that crop out at or near the surface. The Algodonnes fault is inferred to represent the northeast margin of the Salton Trough and apparently an inactive extension of the San Andreas fault system. Extensive well-pumping and applications of irrigation waters in recent years have created an unnatural state of flux in the hydrologic regime in the Yuma area. Gravity and aeromagnetic anomalies trend strongly northwest through the region as do lineaments derived from Landsat and Skylab photos. Electrical resistivity values in the Bouse Formation are exceptionally low, about 3 ohn-m. Heat flow appears to be normal for the Basin and Range province. Ground-water temperatures indicate zones of rising warm water, with one such warm anomaly confirmed by sparse geothermal-gradient data.

  4. Geothermal energy

    OpenAIRE

    Manzella A.

    2015-01-01

    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 p...

  5. Human Resources in Geothermal Development

    Energy Technology Data Exchange (ETDEWEB)

    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.

  6. 2008 Geothermal Technologies Market Report

    Energy Technology Data Exchange (ETDEWEB)

    Cross, J.; Freeman, J.

    2009-07-01

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

  7. Electronics Demonstrated for Low- Temperature Operation

    Science.gov (United States)

    Patterson, Richard L.; Hammond, Ahmad; Gerber, Scott S.

    2000-01-01

    The operation of electronic systems at cryogenic temperatures is anticipated for many NASA spacecraft, such as planetary explorers and deep space probes. For example, an unheated interplanetary probe launched to explore the rings of Saturn would experience an average temperature near Saturn of about 183 C. Electronics capable of low-temperature operation in the harsh deep space environment also would help improve circuit performance, increase system efficiency, and reduce payload development and launch costs. An ongoing research and development program on low-temperature electronics at the NASA Glenn Research Center at Lewis Field is focusing on the design of efficient power systems that can survive and exploit the advantages of low-temperature environments. The targeted systems, which are mission driven, include converters, inverters, controls, digital circuits, and special-purpose circuits. Initial development efforts successfully demonstrated the low-temperature operation and cold-restart of several direct-current/direct-current (dc/dc) converters based on different types of circuit design, some with superconducting inductors. The table lists some of these dc/dc converters with their properties, and the photograph shows a high-voltage, high-power dc/dc converter designed for an ion propulsion system for low-temperature operation. The development efforts of advanced electronic systems and the supporting technologies for low-temperature operation are being carried out in-house and through collaboration with other Government agencies, industry, and academia. The Low Temperature Electronics Program supports missions and development programs at NASA s Jet Propulsion Laboratory and Goddard Space Flight Center. The developed technologies will be transferred to commercial end users for applications such as satellite infrared sensors and medical diagnostic equipment.

  8. Idaho Geothermal Commercialization Program. Idaho geothermal handbook

    Energy Technology Data Exchange (ETDEWEB)

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

    1980-03-01

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

  9. Geothermal direct-heat utilization assistance: Quarterly project progress report, January--March 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    The report summarizes geothermal activities of the Geo-Heat Center at Oregon Institute of Technology for the second quarter of FY-95. It describes 92 contacts with parties during this period related to technical assistance with geothermal direct heat projects. Areas dealt with include geothermal heat pumps, space heating, greenhouses, aquaculture, resources and equipment. Research activities are summarized on geothermal energy cost evaluation, low temperature resource assessment and ground-source heat pump case studies and utility programs. Outreach activities include the publication of a geothermal direct heat Bulletin, dissemination of information, geothermal library, and progress monitor reports on geothermal resources and utilization.

  10. Advanced Geothermal Turbodrill

    Energy Technology Data Exchange (ETDEWEB)

    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.

  11. Advanced Geothermal Turbodrill

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Honggang [Rutgers University; Liu, Xiaobing [ORNL

    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.

  13. Joint Geophysical Assessments of Geothermal Potential from a Deep Borehole in the Canadian Shield Rocks of NE Alberta

    Science.gov (United States)

    Chan, J.; Schmitt, D. R.; Kueck, J.; Moeck, I. S.

    2012-12-01

    Part of the feasibility study for geothermal development in Northern Alberta consists of investigating the presence of subsurface fluid pathways in the crystalline basement rocks. The deepest borehole drilled in Northeastern Alberta has a depth of 2350 m and offers substantial depth coverage to study the basement rocks. Due to the limited cores available for this deep borehole, a comprehensive suite of geophysical logs and borehole seismic methods are used to provide subsurface characterization of the basement in addition to the existing surface seismic reflection data. Interpretation of the geophysical logs indicate potential fracture zones at different depths that could serve as zones with enhanced fluid potential - a necessary component for any geothermal systems to be viable. Fractures within the subsurface tend to be aligned by the deviatoric stress in the subsurface and their orientations can be imaged using the Formation MicroImager (FMI) log. Two sets of vertical seismic profiles (VSP) were acquired in the deep borehole in July 2011. First, a high resolution zero-offset VSP was acquired to measure the seismic responses at the borehole. Upgoing tube waves can be identified and attributed to fracture zones interpreted from the geophysical logs. Since VSP data contains higher frequency content, the final corridor stack from the zero-offset VSP offers greater resolution in correlating seismic reflections with the primary reflectors and multiples interpreted from the surface seismic reflection data. The second set of VSP data is a multi-azimuth, multi-depth walk-away VSP acquired using three-component receivers placed at depths of 800 and 1780 m. The degree of seismic anisotropy in the crystalline basement can be revealed by analyzing the first arrivals at different geophone depths. Using an assumption that the presence of fractures causes P-wave reflection anisotropy, interpretation from the walk-away VSP can be used as a method for gross fracture detection

  14. Geothermal investigations in Slovenia

    Directory of Open Access Journals (Sweden)

    Danilo Ravnik

    1991-12-01

    Full Text Available The paper presents the methodology and the results of geothermal investigations, based on seventy-two boreholes in the territory of the Republic of Slovenia.The data of fundamental geothermal quantities: formation temperature, thermal conductivity, and radiogenic heat production of rocks as well as surface heat flow density are stored in a computerized data base. Their synthesis is given in the map of formation temperatures at 1000 m depth and in the map of surface heat flow density. In both maps the thermal difference between the Pannonian basin in theeastern and the Dinarides in the western part of Slovenia is clearly expressed.However, in the boundary area between these two tectonic units, for a distance of about 100 km in SW-NE direction, elevated horizontal gradients of formation temperature as well as heat flow density are evident. A small positive thermal anomaly in the Ljubljana depression is conspicuous.The low-temperature geothermal resources in Slovenia such as thermalsprings and thermal water from boreholes, are estimated to have a flow rate of 1120 kg/s, corresponding to the ideal total heat production of 144 MWt. In the geothermally promising areas amounting to 3200 km2 the rate of accessible resource base (ARB down to the depth of 3 km has been assessed to about 8.5 x lO 20» J.

  15. QTL analysis of rice low temperature germinability

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A double haploid population, derived from anther culture of F1 hybrid between a typical indica and a japonica (ZYQ8/JX17), has been used to investigate the low temperature germinability (LTG) at 15C. The low temperature germinability of two parents was significantly different.In 6-11 d, the germination percentage of ZYQ8 was higher than that of JX17. In 12-16 d, the germination percentage of JX17 was higher than that of ZYQ8. The quantitative trait loci (QTLs) of every day for low temperature germinability have been mapped based on a molecular linkage map constructed from this population. In 8-11 d, qLTG-9 was identiffed in C397B-RZ617B on chromosome 9, the additive effect was positive, showing that the allele from JX17 could increase low temperature germinability. In 12-16 d, qLTG4 was mapped between RG908 and CT563 on chromosome 4,the additive effect was negative, showing that the allele from ZYQ8 could increase low temperature germinability. These two QTLs were detected at different stages, showing the complexity of the mechanism of iow temperature germinability.

  16. World Geothermal Congress WGC-2015

    Science.gov (United States)

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

    2016-08-01

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

  17. Geothermal Potential of Marine Corps Air Station, Yuma, Arizona, and the Western Portion of Luke-Williams Gunnery Range

    Science.gov (United States)

    1988-01-01

    Domes in the Northern Part of the Gulf of California," in Symposia on the Cerro Prieto Geothermal Field, Baja California, Mexico, Comision Federal de...3) consider the proximity of the Yuma area to the many known geothermal anomalies in the Salton Trough area, as well as the similarities in structure...report), Stone and Witcher note A the zones of anomalously warm ground water in the area and a geothermal -gradient anomaly along the northwest-trending

  18. Navy Geothermal Plan

    Energy Technology Data Exchange (ETDEWEB)

    1984-12-01

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

  19. Geothermal power generation in United States

    Science.gov (United States)

    Braun, Gerald W.; McCluer, H. K.

    1993-03-01

    Geothermal energy is an indigenous environmentally benign heat source with the potential for 5000-10,000 GWe of power generation in the United States. Approximately 2535 MWe of installed capacity is currently operating in the U.S. with contracted power costs down to 4.6 cents/kWh. This paper summarizes: 1) types of geothermal resources; 2) power conversion systems used for geothermal power generation; 3) environmental aspects; 4) geothermal resource locations, potential, and current power plant development; 5) hurdles, bottlenecks, and risks of geothermal power production; 6) lessons learned; and 7) ongoing and future geothermal research programs.

  20. Multidisciplinary research of geothermal modeling

    Science.gov (United States)

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

    2010-05-01

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

  1. An evaluation of the geothermal potential of the Tecuamburro Volcano area of Guatemala

    Energy Technology Data Exchange (ETDEWEB)

    Heiken, G.; Duffield, W. (eds.)

    1990-09-01

    Radiometric ages indicate that the Tecuamburro Volcano and three adjacent lava domes grew during the last 38,300 years, and that a 360-m-wide phreatic crater, Laguna Ixpaco, was formed near the base of these domes about 2900 years ago. Laguna Ixpaco is located within the Chupadero crater, from which pyroxene pumice deposits were erupted 38,300 years ago. Thus, the likelihood is great for a partly molten or solid-but-still-hot near-surface intrusion beneath the area. Fumaroles and hot springs issue locally from the Tecuamburro volcanic complex and near Laguna Ixpaco. Analyses of gas and fluid samples from these and other nearby thermal manifestations yield chemical-geothermometer temperatures of about 150{degree} to 300{degree}C, with the highest temperatures at Ixpaco. The existence of a commercial-grade geothermal reservoir beneath the Ixpaco area seems likely. 84 refs., 70 figs., 12 tabs.

  2. Geothermal source potential and utilization for methane generation and alcohol production

    Energy Technology Data Exchange (ETDEWEB)

    Austin, J.C.

    1981-11-01

    A study was conducted to assess the technical and economic feasibility of integrating a geothermally heated anaerobic digester with a fuel alcohol plant and cattle feedlot. Thin stillage produced from the alcohol production process and manure collected from the cattle feedlot would be digested in anaerobic digesters to produce biogas, a mixture of methane and carbon dioxide, and residue. The energy requirements to maintain proper digester temperatures would be provided by geothermal water. The biogas produced in the digesters would be burned in a boiler to produce low-pressure steam which would be used in the alcohol production process. The alcohol plant would be sized so that the distiller's grains byproduct resulting from the alcohol production would be adequate to supply the daily cattle feed requirements. A portion of the digester residue would substitute for alfalfa hay in the cattle feedlot ration. The major design criterion for the integrated facilty was the production of adequate distiller's grain to supply the daily requirements of 1700 head of cattle. It was determined that, for a ration of 7 pounds of distiller's grain per head per day, a 1 million gpy alcohol facility would be required. An order-of-magnitude cost estimate was prepared for the proposed project, operating costs were calculated for a facility based on a corn feedstock, the economic feasibility of the proposed project was examined by calculating its simple payback, and an analysis was performed to examine the sensitivity of the project's economic viability to variations in feedstock costs and alcohol and distiller's grain prices.

  3. Kinetics and spectroscopy of low temperature plasmas

    CERN Document Server

    Loureiro, Jorge

    2016-01-01

    This is a comprehensive textbook designed for graduate and advanced undergraduate students. Both authors rely on more than 20 years of teaching experience in renowned Physics Engineering courses to write this book addressing the students’ needs. Kinetics and Spectroscopy of Low Temperature Plasmas derives in a full self-consistent way the electron kinetic theory used to describe low temperature plasmas created in the laboratory with an electrical discharge, and presents the main optical spectroscopic diagnostics used to characterize such plasmas. The chapters with the theoretical contents make use of a deductive approach in which the electron kinetic theory applied to plasmas with basis on the electron Boltzmann equation is derived from the basic concepts of Statistical and Plasma Physics. On the other hand, the main optical spectroscopy diagnostics used to characterize experimentally such plasmas are presented and justified from the point of view of the Atomic and Molecular Physics. Low temperature plasmas...

  4. Basics of Low-temperature Refrigeration

    CERN Document Server

    Alekseev, A

    2014-01-01

    This chapter gives an overview of the principles of low temperature refrigeration and the thermodynamics behind it. Basic cryogenic processes - Joule-Thomoson process, Brayton process as well as Claude process - are described and compared. A typical helium laboratory refrigerator based on Claude process is used as a typical example of a low-temperature refrigeration system. A description of the hardware components for helium liquefaction is an important part of this paper, because the design of the main hardware components (compressors, turbines, heat exchangers, pumps, adsorbers, etc.) provides the input for cost calculation, as well as enables to estimate the reliability of the plant and the maintenance expenses. All these numbers are necessary to calculate the economics of a low temperature application.

  5. Radioluminescence and thermoluminescence of albite at low temperature

    Energy Technology Data Exchange (ETDEWEB)

    Can, N., E-mail: cannurdogan@yahoo.com [Physics Department, Faculty of Arts and Sciences, Celal Bayar University, 45140 Muradiye-Manisa (Turkey); Garcia-Guinea, J. [Museo Nacional Ciencias Naturales, Jose Gutierrez Abascal 2, Madrid 28006 (Spain); Kibar, R.; Cetin, A.; Ayvacikli, M. [Physics Department, Faculty of Arts and Sciences, Celal Bayar University, 45140 Muradiye-Manisa (Turkey); Townsend, P.D. [Science and Technology, University of Sussex, Brighton BN1 9QH, England (United Kingdom)

    2011-08-15

    Feldspar as an archaeological and geological natural material for dating and retrospective dosimetry is receiving more and more attention because of its useful luminescence properties. In this study, the 25-280 K thermoluminescence (TL) and radioluminescence (RL) spectra in albite, which is a component of the two main feldspar series, the alkali feldspar (Na, K)AlSi{sub 3}O{sub 8} and the plagioclases (NaAlSi{sub 3}O{sub 8}-CaAl{sub 2}Si{sub 2}O{sub 8}) have been presented for aliquots along (001) and (010) crystallographic orientations. There are four main emission bands that are considered to arise from complexes of intrinsic defects linked in larger complexes with impurities such as Na{sup +}, Mn{sup 2+} or Fe{sup 3+} ions. The consequence of their association is to produce different luminescence efficiencies that produce wavelength sensitive TL curves. Radioluminescence data at low temperature for albites is distorted by contributions from the TL sites, even when the RL is run in a cooling cycle. This indicates the potential for a far more general problem for analysis of low temperature RL in insulating materials. - Highlights: > TL and RL spectra in albite were presented for different orientations. > There are 4 emission bands that are considered to arise from complexes of intrinsic. > RL data at low temperature for albite is distorted by contributions from TL sites. > This indicates the potential problem for analysis of low temperature RL.

  6. An Estimation of Potentials for the Hatchobaru Geothermal Area, Northern Kyushu, Japan and Geo-Electrical Indications at the Otake Geothermal Field in the Western Part of the Kujyu Volcano Group, Kyushu, Japan

    Energy Technology Data Exchange (ETDEWEB)

    Onodera, S.

    1974-01-01

    In the estimation of the output in kW/h produced by the geothermal power generation, it is required to know the well characteristics, the heat cycle in the power plant, the output characteristics and the efficiency. Of these three in the latter are seemed to be constant in the present power plant, while only the well characteristics varies in the wide range. One of great importance in the measurement of well characteristics is the determination of the steam flow rate from a well at a given well head pressure. it is, at present, well-known that the corresponding output in kW based on the steam flow rate is defined as the potential for the geothermal area involved. Specifically, in the case of hydrothermal systems the separate system must be equipped in order to know the steam flow rate.

  7. Low temperature monitoring system for subsurface barriers

    Science.gov (United States)

    Vinegar, Harold J.; McKinzie, II. Billy John

    2009-08-18

    A system for monitoring temperature of a subsurface low temperature zone is described. The system includes a plurality of freeze wells configured to form the low temperature zone, one or more lasers, and a fiber optic cable coupled to at least one laser. A portion of the fiber optic cable is positioned in at least one freeze well. At least one laser is configured to transmit light pulses into a first end of the fiber optic cable. An analyzer is coupled to the fiber optic cable. The analyzer is configured to receive return signals from the light pulses.

  8. Materials for low-temperature fuel cells

    CERN Document Server

    Ladewig, Bradley; Yan, Yushan; Lu, Max

    2014-01-01

    There are a large number of books available on fuel cells; however, the majority are on specific types of fuel cells such as solid oxide fuel cells, proton exchange membrane fuel cells, or on specific technical aspects of fuel cells, e.g., the system or stack engineering. Thus, there is a need for a book focused on materials requirements in fuel cells. Key Materials in Low-Temperature Fuel Cells is a concise source of the most important and key materials and catalysts in low-temperature fuel cells. A related book will cover key materials in high-temperature fuel cells. The two books form part

  9. Systemic low temperature signaling in Arabidopsis.

    Science.gov (United States)

    Gorsuch, Peter A; Sargeant, Alexander W; Penfield, Steven D; Quick, W Paul; Atkin, Owen K

    2010-09-01

    When leaves are exposed to low temperature, sugars accumulate and transcription factors in the C-repeat binding factor (CBF) family are expressed, which, together with CBF-independent pathways, are known to contribute to the cold acclimation process and an increase in freezing tolerance. What is not known, however, is whether expression of these cold-regulated genes can be induced systemically in response to a localized cold treatment. To address this, pre-existing, mature leaves of warm-grown Arabidopsis thaliana were exposed to a localized cold treatment (near 10 °C) whilst conjoined newly developing leaves continued only to experience warmer temperatures. In initial experiments on wild-type A. thaliana (Col-0) using real-time reverse transcription--PCR (RT-PCR) we observed that some genes--including CBF genes, certain downstream cold-responsive (COR) targets and CBF-independent transcription factors--respond to a direct 9 °C treatment of whole plants. In subsequent experiments, we found that the treatment of expanded leaves with temperatures near 10 °C can induce cold-associated genes in conjoined warm-maintained tissues. CBF1 showed a particularly strong systemic response, although CBF-independent transcription factors also responded. Moreover, the localized cold treatment of A. thaliana (C24) plants with a luciferase reporter fused to the promoter region of KIN2 indicated that in warm-maintained leaves, KIN2 might respond to a systemic signal from remote, directly cold-treated leaves. Collectively, our study provides strong evidence that the processes involved in cold acclimation are partially mediated by a signal that acts systemically. This has the potential to act as an early-warning system to enable developing leaves to cope better with the cold environment in which they are growing.

  10. Nevada low-temperaure geothermal resource assessment: 1994. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Garside, L.J.

    1994-12-31

    Data compilation for the low-temperature program is being done by State Teams in two western states. Final products of the study include: a geothermal database, in hardcopy and as digital data (diskette) listing information on all known low- and moderate- temperature springs and wells in Nevada; a 1:1,000,000-scale map displaying these geothermal localities, and a bibliography of references on Nevada geothermal resources.

  11. Using Geothermal Energy for Raffine Heating in Copper Production

    OpenAIRE

    Arnar Freyr Sigmundsson 1985

    2012-01-01

    The aim of this work was to study the feasibility of using geothermal energy for heating raffine (raffinate) solution in the process of copper production. Small-scale experiments have indicated that copper extraction levels can be improved significantly by adding heat to the solution. Two thermal energy sources were considered, namely the cooling water sourced from an adjacent geothermal power plant and low-temperature geothermal brine produced in the vicinity of the mine. These two alternati...

  12. IRETHERM: Developing a Strategic and Holistic Understanding of Ireland's Geothermal Energy Potential through Integrated Modelling of New and Existing Geophysical, Geochemical and Geological Data

    Science.gov (United States)

    Jones, Alan G.; Daly, Stephen; Vozar, Jan; Rath, Volker; Campanya, Joan; Blake, Sarah; Delhaye, Robert; Fritschle, Tobias; Willmot Noller, Nicola; Long, Mike; Waters, Tim

    2015-04-01

    The Science Foundation Ireland funded academia-government-industry collaborative IRETHERM project (www.iretherm.ie), initiated in 2011, is developing a strategic understanding of Ireland's (all-island) deep geothermal energy potential through integrated modelling of new and existing geophysical, geochemical and geological data. Potential applications include both low enthalpy district space heating of large urban centres and electricity generation from intermediate-temperature waters. IRETHERM comprises three broad geothermal target types; 1) Assessment of the geothermal energy potential of Ireland's radiogenic granites (EGS), (2) Assessment of the geothermal energy potential of Ireland's deep sedimentary basins (HSA), and, (3) Assessment of the geothermal energy potential of warm springs. The geophysical subsurface imaging techniques of choice are controlled-source (CSEM) and natural-source (magnetotellurics, MT) electromagnetic methods. Electrical conductivity, being a transport property, is a proxy for permeability, and appropriate porosity-permeability relations are being developed. To date, MT measurements have been made at 466 sites over sedimentary basins (190 sites), granites (156 sites) and warm springs (120 sites), with CSEM across one warm spring. An ongoing continuous geochemical (temperature and electrical conductivity every 15 mins) and time-lapse seasonal hydrochemical sampling programmes are in progress at six warm spring sites. A database on heat production in Irish rocks has been compiled, of more than 3,300 geochemical sample measurements, with 3,000 retrieved from various archives and over 300 new analyses. Geochemistry, geochronology and isotopic analyses have been conducted on subsurface granites and exposed analogues astride the Iapetus Suture Zone in order to understand the underlying reasons for their radiogenic heat production. Finally, thermal conductivity measurements have been made on borehole samples from representative lithologies

  13. Isotopic and chemical assessment of geothermal potential of the Colli Albani area, Latium region, Italy

    Energy Technology Data Exchange (ETDEWEB)

    Giggenbach, W.F.; Minissale, A.A.; Scandiffio, G.

    The chemical and isotopic compositions of low-temperature mineral waters discharged over the Colli Albani region (south of Rome, Italy) are those of highly immature waters of essentially meteoric origin formed through absorption of gases emanating from greater depth, followed by cation leaching of country rock at shallow levels. The composition of the gases discharged points to the presence, at depth, of a CO/sub 2/-producing high temperature system in its waning stage. Low H/sub 2/ and unsaturated hydrocarbon contents, as well as relative He, Ar and N/sub 2/ contents indicate long residence time for the rising gas phase of the order of 1 Ma. On the basis of these findings, temperatures higher than 120/sup 0/C appear unlikely to exist at shallow depth.

  14. Infrastructure and mechanical properties of a fault zone in sandstone as an outcrop analogue of a potential geothermal reservoir

    Science.gov (United States)

    Bauer, J. F.; Meier, S.; Philipp, S. L.

    2013-12-01

    Due to high drilling costs of geothermal projects, it is economically sensible to assess the potential suitability of a reservoir prior to drilling. Fault zones are of particular importance, because they may enhance fluid flow, or be flow barriers, respectively, depending on their particular infrastructure. Outcrop analogue studies are useful to analyze the fault zone infrastructure and thereby increase the predictability of fluid flow behavior across fault zones in the corresponding deep reservoir. The main aims of the present study are to 1) analyze the infrastructure and the differences of fracture system parameters in fault zones and 2) determine the mechanical properties of the faulted rocks. We measure fracture frequencies as well as orientations, lengths and apertures and take representative rock samples for each facies to obtain Young's modulus, compressive and tensile strengths in the laboratory. Since fractures reduce the stiffnesses of in situ rock masses we use an inverse correlation of the number of discontinuities to calculate effective (in situ) Young's moduli to investigate the variation of mechanical properties in fault zones. In addition we determine the rebound hardness, which correlates with the compressive strength measured in the laboratory, with a 'Schmidt-Hammer' in the field because this allows detailed maps of mechanical property variations within fault zones. Here we present the first results for a fault zone in the Triassic Lower Bunter of the Upper Rhine Graben in France. The outcrop at Cleebourg exposes the damage zone of the footwall and a clear developed fault core of a NNW-SSE-striking normal fault. The approximately 15 m wide fault core consists of fault gouge, slip zones, deformation bands and host rock lenses. Intensive deformation close to the core led to the formation of a distal fault core, a 5 m wide zone with disturbed layering and high fracture frequency. The damage zone also contains more fractures than the host rock

  15. Low Temperature Surface Carburization of Stainless Steels

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Sunniva R; Heuer, Arthur H; Sikka, Vinod K

    2007-12-07

    Low-temperature colossal supersaturation (LTCSS) is a novel surface hardening method for carburization of austenitic stainless steels (SS) without the precipitation of carbides. The formation of carbides is kinetically suppressed, enabling extremely high or colossal carbon supersaturation. As a result, surface carbon concentrations in excess of 12 at. % are routinely achieved. This treatment increases the surface hardness by a factor of four to five, improving resistance to wear, corrosion, and fatigue, with significant retained ductility. LTCSS is a diffusional surface hardening process that provides a uniform and conformal hardened gradient surface with no risk of delamination or peeling. The treatment retains the austenitic phase and is completely non-magnetic. In addition, because parts are treated at low temperature, they do not distort or change dimensions. During this treatment, carbon diffusion proceeds into the metal at temperatures that constrain substitutional diffusion or mobility between the metal alloy elements. Though immobilized and unable to assemble to form carbides, chromium and similar alloying elements nonetheless draw enormous amounts of carbon into their interstitial spaces. The carbon in the interstitial spaces of the alloy crystals makes the surface harder than ever achieved before by more conventional heat treating or diffusion process. The carbon solid solution manifests a Vickers hardness often exceeding 1000 HV (equivalent to 70 HRC). This project objective was to extend the LTCSS treatment to other austenitic alloys, and to quantify improvements in fatigue, corrosion, and wear resistance. Highlights from the research include the following: • Extension of the applicability of the LTCSS process to a broad range of austenitic and duplex grades of steels • Demonstration of LTCSS ability for a variety of different component shapes and sizes • Detailed microstructural characterization of LTCSS-treated samples of 316L and other alloys

  16. Geothermal development plan: Maricopa county

    Energy Technology Data Exchange (ETDEWEB)

    White, D.H.

    1981-01-01

    Maricopa county is the area of Arizona receiving top priority since it contains over half of the state's population. The county is located entirely within the Basin and Range physiographic region in which geothermal resources are known to occur. Several approaches were taken to match potential users to geothermal resources. One approach involved matching some of the largest facilities in the county to nearby geothermal resources. Other approaches involved identifying industrial processes whose heat requirements are less than the average assessed geothermal reservoir temperature of 110/sup 0/C (230/sup 0/F). Since many of the industries are located on or near geothermal resources, geothermal energy potentially could be adapted to many industrial processes.

  17. Geothermal development plan: Maricopa county

    Energy Technology Data Exchange (ETDEWEB)

    White, D.H.

    1981-01-01

    Maricopa county is the area of Arizona receiving top priority since it contains over half of the state's population. The county is located entirely within the Basin and Range physiographic region in which geothermal resources are known to occur. Several approaches were taken to match potential users to geothermal resources. One approach involved matching some of the largest facilities in the county to nearby geothermal resources. Other approaches involved identifying industrial processes whose heat requirements are less than the average assessed geothermal reservoir temperature of 110/sup 0/C (230/sup 0/F). Since many of the industries are located on or near geothermal resources, geothermal energy potentially could be adapted to many industrial processes.

  18. Low temperature anodic bonding to silicon nitride

    DEFF Research Database (Denmark)

    Weichel, Steen; Reus, Roger De; Bouaidat, Salim;

    2000-01-01

    Low-temperature anodic bonding to stoichiometric silicon nitride surfaces has been performed in the temperature range from 3508C to 4008C. It is shown that the bonding is improved considerably if the nitride surfaces are either oxidized or exposed to an oxygen plasma prior to the bonding. Both bulk...

  19. Design trends in low temperature gas processing

    Energy Technology Data Exchange (ETDEWEB)

    White, W.E.; Battershell, D.D.

    1966-01-01

    The following basic trends reflected in recent design of low-temperature gas processing are discussed: (1) higher recovery levels of light hydrocarbon products; (2) lower process temperatures and lighter absorption oils; (3) increased thermodynamic efficiencies; (4) automation; (5) single rather than multiple units; and (6) prefabrication and preassembly of the operating unit.

  20. Induction methods used in low temperature physics

    NARCIS (Netherlands)

    van de Klundert, L.J.M.; de Rooij, C.; Caspari, M.; van der Marel, L.C.

    1975-01-01

    A study has been made of induction bridges used in low temperature physics. In Part 1 the design of a mutual inductance bridge of the Hartshorn type is discussed. This design is based on a critical analysis of impurity effects of the different parts of the Hartshorn bridge. With this equipment

  1. Industrial Applications of Low Temperature Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Bardsley, J N

    2001-03-15

    The use of low temperature plasmas in industry is illustrated by the discussion of four applications, to lighting, displays, semiconductor manufacturing and pollution control. The type of plasma required for each application is described and typical materials are identified. The need to understand radical formation, ionization and metastable excitation within the discharge and the importance of surface reactions are stressed.

  2. Fuzzy Logic Controller for Low Temperature Application

    Science.gov (United States)

    Hahn, Inseob; Gonzalez, A.; Barmatz, M.

    1996-01-01

    The most common temperature controller used in low temperature experiments is the proportional-integral-derivative (PID) controller due to its simplicity and robustness. However, the performance of temperature regulation using the PID controller depends on initial parameter setup, which often requires operator's expert knowledge on the system. In this paper, we present a computer-assisted temperature controller based on the well known.

  3. The holographic screen at low temperatures

    CERN Document Server

    Kiselev, V V

    2010-01-01

    A permissible spectrum of transverse vibrations for the holographic screen modifies both a distribution of thermal energy over bits at low temperatures and the law of gravitation at small accelerations of free fall in agreement with observations of flat rotation curves in spiral galaxies. This modification relates holographic screen parameters in de Sitter space-time with the Milgrom acceleration in MOND.

  4. Wood preservation of low-temperature carbonisation

    NARCIS (Netherlands)

    Gosselink, R.J.A.; Krosse, A.M.A.; Putten, van der J.C.; Kolk, van der J.C.; Klerk-Engels, de B.; Dam, van J.E.G.

    2004-01-01

    Pine (Pinus sylvestris L.) wood with dimensions (100 x 10 x 10mm) was thermally treated at 275degreesC in a muffle oven to impart resistance to microbial degradation. Low-temperature carbonised pine resulted in a visually homogeneously treated product with a substantial (about 70% w/w) reduced non-c

  5. Analyzing the Potential for Unmanned Aerial Systems (UAS) Photogrammetry in Estimating Surface Deformations at a Geothermal Fiel

    Science.gov (United States)

    Pai, H.; Burnett, J.; Sladek, C.; Wing, M.; Feigl, K. L.; Selker, J. S.; Tyler, S.; Team, P.

    2016-12-01

    UAS systems equipped with a variety of spectral imaging devices are increasingly incorporated in spatial environmental assessments of continental surfaces (e.g., digital elevation maps, vegetative coverage classifications, surface temperatures). This presented work performed by the UAS team at the Center for Transformative Environmental Monitoring Programs (AirCTEMPS) examines the potential to measure small (sub-cm) deformation from a geothermal injection experiment at Brady's geothermal field in western Nevada (USA). Areal mapping of the 700 x 270 m area of interest was conducted with a nadir pointing Sony A5100 digital camera onboard an autopiloted quadcopter. A total of 16 ground control points were installed using a TopCon GR3 GPS receiver. Two such mapping campaigns were conducted with one before and one after an anticipated surface deformation event. A digital elevation map (DEM) for each time period was created from over 1500 images having 80% overlap/sidelap by using structure from motion (SfM) via Agisoft Photoscan software. The resulting DEM resolution was 8 mm/pixel with residual aerial triangulation errors was differential DEM heights between campaigns at the cm-scale which is broader than the maximum expected deformation. Despite the disconnect between error and deformation severity, this study presents a unique application of sub-cm UAS-based DEMs and further distinguishes itself by comparing results to concurrent Interferometric Synthetic Radar (InSAR). The intent of our study and presentation of results is to streamline, cross-validate, and share methods to encourage further adoption of UAS imagery into the standard toolkit for environmental surface sensing across spatial scales.

  6. Water Desalination Using Geothermal Energy

    OpenAIRE

    Noreddine Ghaffour; , Hacene Mahmoudi; Mattheus Goosen

    2010-01-01

    The paper provides a critical overview of water desalination using geothermal resources. Specific case studies are presented, as well as an assessment of environmental risks and market potential and barriers to growth. The availability and suitability of low and high temperature geothermal energy in comparison to other renewable energy resources for desalination is also discussed. Analysis will show, for example, that the use of geothermal energy for thermal desalination can be justified only...

  7. Modern geothermal power: GeoPP with geothermal steam turbines

    Science.gov (United States)

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

    2017-03-01

    The first part of the review presents information on the scale and specific features of geothermal energy development in various countries. The classification of geothermal power plant (GeoPP) process flow diagrams by a phase state of the primary heat source (a geothermal fluid), thermodynamic cycle, and applicable turbines is proposed. Features of geothermal plants using methods of flashing and steam separation in the process loop and a flowsheet and thermodynamic process of a geothermal fluid heat-to-power conversion in a GeoPP of the most widespread type using a double-flash separation are considered. It is shown that, for combined cycle power units, the specific power-to-consumption geothermal fluid ratio is 20-25% higher than that for traditional single-loop GeoPP. Information about basic chemical components and their concentration range for geothermal fluids of various formations around the world is presented. Three historic stages of improving geothermal energy technologies are determined, such as development of high-temperature geothermal resources (dry, superheated steam) and application of a two-phase wet-steam geothermal fluid in GeoPP power units with one or two expansion pressures and development of binary cycle GeoPPs. A current trend of more active use of binary power plants in GeoPP technological processes is noted. Design features of GeoPP's steam turbines and steam separating devices, determined by the use of low-potential geothermal saturated steam as a working medium, which is characterized by corrosion aggressiveness and a tendency to form deposits, are considered. Most promising Russian geothermal energy projects are determined. A list of today's most advanced geothermal turbine performance technologies is presented. By an example of a 25 MW steam turbine design, made by JSC Kaluga Turbine Works, advantages of the internal moisture separation with a special turbine-separator stage are shown.

  8. Three-dimensional inversion of self-potential data used to constrain the pattern of groundwater flow in geothermal fields

    Science.gov (United States)

    Jardani, A.; Revil, A.; BolèVe, A.; Dupont, J. P.

    2008-09-01

    We propose an algorithm to invert self-potential signals measured at the ground surface of the Earth to localize hydromechanical disturbances or to the pattern of groundwater flow in geothermal systems. The self-potential signals result from the divergence of the streaming current density. Groundwater flow can be either driven by topography of the water table, free convection, or deformation of the medium. The algorithm includes the electrical resistivity distribution of the medium obtained independently by DC resistance tomography or electromagnetic methods or by coding the assumed geology in terms of distribution of the electrical resistivity accounting for the effect of the temperature and salinity distributions and possibly constraints from borehole measurements. Inversion of the distribution of the source current density from ground surface and borehole self-potential measurements is achieved by solving the inverse problem using Tikhonov regularization solutions that are compatible with the physics of the primary flow problem. By introducing assumptions regarding the smoothness or the compactness of the source and the three-dimensional distribution of the electrical resistivity of the system, the inverse problem can be solved in obtaining the three-dimensional distribution of the current source density in the ground. However, an annihilator can be added to the inverted source geometry without affecting the measured self-potential field. Annihilators can be obtained from boundary conditions. Synthetic models and a sandbox experiment are discussed to demonstrate the validity of the algorithm. An application is presented to the geothermal field of Cerro Prieto, Baja California, Mexico, using literature data. Inversion of the self-potential and resistivity data allows observing a plume of hot groundwater rising to the ground surface in the central part of the investigated area and discharging to the ground surface in the southwest part. The temperature anomaly

  9. GEOTHERMICS GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    <正>20122531 Hu Lingzhi ( Institute of Geological Engineering Design & Research of Beijing,Miyun 101500,China );Wang Jiankang Discussion on the Feasibility of Geothermal Resources Development and Utilization in Miyun District,Beijing ( City Geology,ISSN1007-1903,CN11-5519 / P,6 ( 3 ), 2011,p.34-35,59 ,) Key words:geothermal resources,Beijing Geothermal,as a new type of clean energy with the integrated trinity of " heat energy-mineral resource-water resource ",

  10. GEOTHERMICS GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    20150342Guan Yu(Geo-Environment Monitoring Station of Anhui Province,Hefei230001,China);Chen Xun On Shallow Geothermal Energy Investigation in Urban Planning Zone of Bengbu in Anhui Province(Journal of Geology,ISSN1674-3636,CN32-1796/P,38(1),2014,p.88-93,2illus.,4tables,6refs.)Key words:geothermal energy,Anhui Province The authors conducted studies on shallow geothermal energy in urban planning zone in Bengbu of Anhui Province,depicted the geological settings of shallow geothermal energy,analyzed the natural features,heat exchange

  11. Geothermal Handbook

    Energy Technology Data Exchange (ETDEWEB)

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

    1977-06-01

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

  12. Geothermal direct-heat utilization assistance. Quarterly project progress report, April--June 1993

    Energy Technology Data Exchange (ETDEWEB)

    Lienau, P.

    1993-06-01

    Technical assistance was provided to 60 requests from 19 states. R&D progress is reported on: evaluation of lineshaft turbine pump problems, geothermal district heating marketing strategy, and greenhouse peaking analysis. Two presentations and one tour were conducted, and three technical papers were prepared. The Geothermal Progress Monitor reported: USGS Forum on Mineral Resources, Renewable Energy Tax Credits Not Working as Congress Intended, Geothermal Industry Tells House Panel, Newberry Pilot Project, and Low-Temperature Geothermal Resources in Nevada.

  13. Direct application of geothermal energy

    Energy Technology Data Exchange (ETDEWEB)

    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)

  14. Water Desalination Using Geothermal Energy

    Directory of Open Access Journals (Sweden)

    Noreddine Ghaffour

    2010-08-01

    Full Text Available The paper provides a critical overview of water desalination using geothermal resources. Specific case studies are presented, as well as an assessment of environmental risks and market potential and barriers to growth. The availability and suitability of low and high temperature geothermal energy in comparison to other renewable energy resources for desalination is also discussed. Analysis will show, for example, that the use of geothermal energy for thermal desalination can be justified only in the presence of cheap geothermal reservoirs or in decentralized applications focusing on small-scale water supplies in coastal regions, provided that society is able and willing to pay for desalting.

  15. Water Desalination using geothermal energy

    KAUST Repository

    Goosen, M.

    2010-08-03

    The paper provides a critical overview of water desalination using geothermal resources. Specific case studies are presented, as well as an assessment of environmental risks and market potential and barriers to growth. The availability and suitability of low and high temperature geothermal energy in comparison to other renewable energy resources for desalination is also discussed. Analysis will show, for example, that the use of geothermal energy for thermal desalination can be justified only in the presence of cheap geothermal reservoirs or in decentralized applications focusing on small-scale water supplies in coastal regions, provided that society is able and willing to pay for desalting. 2010 by the authors; licensee MDPI, Basel, Switzerland.

  16. Manufacturing Demonstration Facility: Low Temperature Materials Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Graham, David E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Moon, Ji-Won [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Armstrong, Beth L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Datskos, Panos G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Duty, Chad E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gresback, Ryan [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ivanov, Ilia N. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jacobs, Christopher B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jellison, Gerald Earle [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jang, Gyoung Gug [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Joshi, Pooran C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jung, Hyunsung [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Meyer, III, Harry M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Phelps, Tommy [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-06-30

    The Manufacturing Demonstration Facility (MDF) low temperature materials synthesis project was established to demonstrate a scalable and sustainable process to produce nanoparticles (NPs) for advanced manufacturing. Previous methods to chemically synthesize NPs typically required expensive, high-purity inorganic chemical reagents, organic solvents and high temperatures. These processes were typically applied at small laboratory scales at yields sufficient for NP characterization, but insufficient to support roll-to-roll processing efforts or device fabrication. The new NanoFermentation processes described here operated at a low temperature (~60 C) in low-cost, aqueous media using bacteria that produce extracellular NPs with controlled size and elemental stoichiometry. Up-scaling activities successfully demonstrated high NP yields and quality in a 900-L pilot-scale reactor, establishing this NanoFermentation process as a competitive biomanufacturing strategy to produce NPs for advanced manufacturing of power electronics, solid-state lighting and sensors.

  17. Low-temperature sterilization and new technologies.

    Science.gov (United States)

    Goveia, Vania Regina; Pinheiro, Silma Maria Cunha; Graziano, Kazuko Uchikawa

    2007-01-01

    The new low-temperature sterilization technologies are presented as an alternative to the use of ethylene oxide. This review was performed in order to identify evidences of the antimicrobial activity, toxicity, adverse events and the applicability of these technologies. The research was carried through the electronic databases MEDLINE and LILACS up to 2005. The authors analyzed 10 articles in this survey. The studies about the efficacy of these sterilization methods constitute experimental and comparative research that showed the influence of the extension and diameter of the lumen, besides the presence of crystal salts. Thus, choosing the correct equipment is essential, as well as the assurance of the cleansing of the devices, which interfere with the effectiveness of the low-temperature sterilization. These technologies present limitations regarding the sterilization of graft bone and affect the materials properties.

  18. Peltier effect for producing low temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Hamerak, K.

    1981-01-01

    In connection with the technically extremely difficult and exacting problems of space travel, years ago in the United States the urgent demand for extremely space-saving and at the same time extremely reliable systems for producing continuously variable low temperatures came up. Neither then nor today the set task could be satisfactorily solved using the usual procedures of low-temperature-technology. Looking for a suitable heat pump the engineers came across a physical phenomenon known for more than 130 years: the Peltier effect. In contrast to conventional thermodynamic heat pumps, cooling or heating can be achieved by means of thermoelectric arrangeemnts based on the Peltier effect and depending on the direction of current. The Peltier cells combine a high reliability of functions with small dimensions since they have no system components in motion.

  19. Stratigraphy, sedimentology, and geothermal reservoir potential of the volcaniclastic Cura-Mallín succession at Lonquimay, Chile

    Science.gov (United States)

    Pedroza, Viviana; Le Roux, Jacobus P.; Gutiérrez, Néstor M.; Vicencio, Vladimir E.

    2017-08-01

    The Tolhuaca Volcano near Lonquimay in south-central Chile has been the subject of several studies due to its geothermal manifestations, but little is known about the stratigraphy and reservoir potential of the Cura-Mallín Formation forming its basement. Field work and U-Pb dating of detrital zircons allow us to redefine this succession as the Cura-Mallín Group, consisting of the volcano-sedimentary Guapitrío Formation, sedimentary Río Pedregoso Formation, and volcano-sedimentary Mitrauquén Formation. The Río Pedregoso Formation can be subdivided into three formal units, namely the Quilmahue Member, Rucañanco Member, and Bío-Bío Member. The base of the Quilmahue Member interfingers laterally with the base of the Guapitrío Formation, for which a previous K/Ar date of 22.0 ± 0.9 Ma was apparently discarded by the original authors. However, this date is consistent with the stratigraphic position of the Quilmahue Member and new zircon dates from the overlying units, also coinciding with the initiation of an extensional phase in the Bíobío-Aluminé Basin. Deposition of the Quilmahue Member continued throughout the early Miocene, as confirmed by dates of 17.5 Ma reported by previous authors and 16.5 Ma obtained in this study. The Rucañanco Member was deposited during the Serravalian around 12.6 Ma, whereas the Bío-Bío Member was dated at the Serravalian-Tortonian limit (11.6 Ma). Although all three members were deposited in a fluvio-lacustrine environment, they were dominated respectively by flood plains with crevasse splays, lake margins with distributary mouth bars and Gilbert-type deltas, and distal braided and meandering rivers. Whereas the Quilmahue Member was deposited during basin extension, the Rucañanco Member was formed during a period of basin inversion and compression. Temporary tectonic quiescence during deposition of the Bío-Bío Member allowed denudation of the landscape, but around 9.5 Ma tectonism was renewed again during deposition of

  20. Low-temperature heat transfer in nanowires

    OpenAIRE

    Glavin, B. A.

    2000-01-01

    The new regime of low-temperature heat transfer in suspended nanowires is predicted. It takes place when (i) only ``acoustic'' phonon modes of the wire are thermally populated and (ii) phonons are subject to the effective elastic scattering. Qualitatively, the main peculiarities of heat transfer originate due to appearance of the flexural modes with high density of states in the wire phonon spectrum. They give rise to the $T^{1/2}$ temperature dependence of the wire thermal conductance. The e...

  1. Low-Temperature Spacecraft: Challenges/Opportunities

    Science.gov (United States)

    Dickman, J. E.; Patterson, R. L.; Overton, E.; Hammoud, A. N.; Gerber, S. S.

    2001-01-01

    Imagine sending a spacecraft into deep space that operates at the ambient temperature of its environment rather than hundreds of degrees Kelvin warmer. The average temperature of a spacecraft warmed only by the sun drops from 279 K near the Earth's orbit to 90 K near the orbit of Saturn, and to 44 K near Pluto's orbit. At present, deep space probes struggle to maintain an operating temperature near 300 K for the onboard electronics. To warm the electronics without consuming vast amounts of electrical energy, radioisotope heater units (RHUs) are used in vast numbers. Unfortunately, since RHU are always 'on', an active thermal management system is required to reject the excess heat. A spacecraft designed to operate at cryogenic temperatures and shielded from the sun by a large communication dish or solar cell array could be less complex, lighter, and cheaper than current deep space probes. Before a complete low-temperature spacecraft becomes a reality, there are several challenges to be met. Reliable cryogenic power electronics is one of the major challenges. The Low-Temperature Power Electronics Research Group at NASA Glenn Research Center (GRC) has demonstrated the ability of some commercial off the shelf power electronic components to operate at temperatures approaching that of liquid nitrogen (77 K). Below 77 K, there exists an opportunity for the development of reliable semiconductor power switching technologies other than bulk silicon CMOS. This paper will report on the results of NASA GRC's Low-Temperature Power Electronics Program and discuss the challenges to (opportunities for) the creation of a low-temperature spacecraft.

  2. Minimizing material damage using low temperature irradiation

    Science.gov (United States)

    Craven, E.; Hasanain, F.; Winters, M.

    2012-08-01

    Scientific advancements in healthcare driven both by technological breakthroughs and an aging and increasingly obese population have lead to a changing medical device market. Complex products and devices are being developed to meet the demands of leading edge medical procedures. Specialized materials in these medical devices, including pharmaceuticals and biologics as well as exotic polymers present a challenge for radiation sterilization as many of these components cannot withstand conventional irradiation methods. The irradiation of materials at dry ice temperatures has emerged as a technique that can be used to decrease the radiation sensitivity of materials. The purpose of this study is to examine the effect of low temperature irradiation on a variety of polymer materials, and over a range of temperatures from 0 °C down to -80 °C. The effectiveness of microbial kill is also investigated under each of these conditions. The results of the study show that the effect of low temperature irradiation is material dependent and can alter the balance between crosslinking and chain scission of the polymer. Low temperatures also increase the dose required to achieve an equivalent microbiological kill, therefore dose setting exercises must be performed under the environmental conditions of use.

  3. Computational Chemistry of Cyclopentane Low Temperature Oxidation

    KAUST Repository

    El Rachidi, Mariam

    2015-03-30

    Cycloalkanes are significant constituents of conventional fossil fuels, but little is known concerning their combustion chemistry and kinetics, particularly at low temperatures. This study investigates the pressure dependent kinetics of several reactions occurring during low-temperature cyclopentane combustion using theoretical chemical kinetics. The reaction pathways of the cyclopentyl + O2 adduct is traced to alkylhydroperoxide, cyclic ether, β-scission and HO2 elimination products. The calculations are carried out at the UCCSD(T)-F12b/cc-pVTZ-F12//M06-2X/6-311++G(d,p) level of theory. The barrierless entrance channel is treated using variable-reaction-coordinate transition state theory (VRC-TST) at the CASPT2(7e,6o) level of theory, including basis set, geometry relaxation and ZPE corrections. 1-D time-dependent multiwell master equation analysis is used to determine pressure-and temperature-dependent rate parameters of all investigated reactions. Tunneling corrections are included using Eckart barriers. Comparison with cyclohexane is used to elucidate the effect of ring size on the low temperature reactivity of naphthenes. The rate coefficients reported herein are suitable for use in cyclopentane and methylcyclopentane combustion models, even below ~900 K, where ignition is particularly sensitive to these pressure-dependent values.

  4. Thermal expansion of glasses at low temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Lyon, K.G.

    1979-01-01

    The linear thermal expansion coefficient (..cap alpha.. = (par. deltalnL/par. deltaT)/sub p/) was measured at temperatures to 1.2K for two amorphous solids, fused silica and PMMA (polymethylmethacrylate, plexiglas), using a parallel plate capacitor differential dilatometer. The low temperature expansion coefficients for these solids have the same temperature dependences as the specific heats, and show a contribution which is linear in the temperature and which can be associated with the postulate of a broad distribution of two level states. The Grueneisen parameters which are associated with this contribution are comparable for the two solids (Y approx. = -16), and suggest a further indication of common behavior for amorphous solids at low temperature. Large magnitudes for Grueneisen parameters (/..gamma../ > 5) generally are associated with tunneling models. A symmetric double harmonic oscillator tunneling model can be used to understand the sign and magnitude of ..gamma.. for these solids. This model is inconsistent with other thermal and thermodynamic data for fused silica. The existence of similar negative and large magnitude Grueneisen parameters for these two amorphous solids places an additional constraint on theories for the low temperature properties of glasses.

  5. Engineering and economic evaluation of direct hot-water geothermal energy applications on the University of New Mexico campus. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Kauffman, D.; Houghton, A.V.

    1980-12-31

    The potential engineering and economic feasibility of low-temperature geothermal energy applications on the campus of the University of New Mexico is studied in detail. This report includes three phases of work: data acquisition and evaluation, system synthesis, and system refinement and implementation. Detailed process designs are presented for a system using 190/sup 0/F geothermal water to substitute for the use of 135 x 10/sup 9/ Btu/y (141 TJ/y) of fossil fuels to provide space and domestic hot water heating for approximately 23% of the campus. Specific areas covered in the report include economic evaluation, environmental impact and program implementation plans.

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

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Arlene [United States Department of Energy; Blackwell, David [Southern Methodist University; Chickering, Cathy [Southern Methodist University; Boyd, Toni [Oregon Institute of Technology; Horne, Roland [Stanford University; MacKenzie, Matthew [Uberity Technology Corporation; Moore, Joseph [University of Utah; Nickull, Duane [Uberity Technology Corporation; Richard, Stephen [Arizona Geological survey; Shevenell, Lisa A. [University of Nevada, Reno

    2013-01-01

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

  7. Low Temperature Surface Carburization of Stainless Steels

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Sunniva R; Heuer, Arthur H; Sikka, Vinod K

    2007-12-07

    Low-temperature colossal supersaturation (LTCSS) is a novel surface hardening method for carburization of austenitic stainless steels (SS) without the precipitation of carbides. The formation of carbides is kinetically suppressed, enabling extremely high or colossal carbon supersaturation. As a result, surface carbon concentrations in excess of 12 at. % are routinely achieved. This treatment increases the surface hardness by a factor of four to five, improving resistance to wear, corrosion, and fatigue, with significant retained ductility. LTCSS is a diffusional surface hardening process that provides a uniform and conformal hardened gradient surface with no risk of delamination or peeling. The treatment retains the austenitic phase and is completely non-magnetic. In addition, because parts are treated at low temperature, they do not distort or change dimensions. During this treatment, carbon diffusion proceeds into the metal at temperatures that constrain substitutional diffusion or mobility between the metal alloy elements. Though immobilized and unable to assemble to form carbides, chromium and similar alloying elements nonetheless draw enormous amounts of carbon into their interstitial spaces. The carbon in the interstitial spaces of the alloy crystals makes the surface harder than ever achieved before by more conventional heat treating or diffusion process. The carbon solid solution manifests a Vickers hardness often exceeding 1000 HV (equivalent to 70 HRC). This project objective was to extend the LTCSS treatment to other austenitic alloys, and to quantify improvements in fatigue, corrosion, and wear resistance. Highlights from the research include the following: • Extension of the applicability of the LTCSS process to a broad range of austenitic and duplex grades of steels • Demonstration of LTCSS ability for a variety of different component shapes and sizes • Detailed microstructural characterization of LTCSS-treated samples of 316L and other alloys

  8. 2016 Geothermal Technologies Office Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2017-03-01

    This report highlights project successes and continued efforts in all of our program areas – EGS, Hydrothermal, Low-Temperature, and Systems Analysis – which are flanked by useful tools and resources and links to more information. Such highlights include FORGE and EGS successes, projects reducing geothermal costs and risks, and advancements in technology research and development.

  9. The Future of Geothermal Energy

    Energy Technology Data Exchange (ETDEWEB)

    Kubik, Michelle [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    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.

  10. GEOTHERMICS GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    <正>20131088 Fan Difu (Geological Survey of Jiangsu Province , Nanjing 210018 , China ); Xu Xueqiu Origin Study of Geothermal Field in Xiaoyangkou of Rudong County in Jiangsu (Journal of Geology , ISSN1674-3636 , CN32-1796/P , 36 (2), 2012 , p.192-197 , 3illus. , 9refs.) Key words : geothermal fields , Jiangsu Province

  11. Geothermal Energy

    Energy Technology Data Exchange (ETDEWEB)

    Steele, B.C.; Pichiarella, L.S. [eds.; 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.

  12. Choice of optimal working fluid for binary power plants at extremely low temperature brine

    Science.gov (United States)

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

    2016-12-01

    The geothermal energy development problems based on using binary power plants utilizing lowpotential geothermal resources are considered. It is shown that one of the possible ways of increasing the efficiency of heat utilization of geothermal brine in a wide temperature range is the use of multistage power systems with series-connected binary power plants based on incremental primary energy conversion. Some practically significant results of design-analytical investigations of physicochemical properties of various organic substances and their influence on the main parameters of the flowsheet and the technical and operational characteristics of heat-mechanical and heat-exchange equipment for binary power plant operating on extremely-low temperature geothermal brine (70°C) are presented. The calculation results of geothermal brine specific flow rate, capacity (net), and other operation characteristics of binary power plants with the capacity of 2.5 MW at using various organic substances are a practical interest. It is shown that the working fluid selection significantly influences on the parameters of the flowsheet and the operational characteristics of the binary power plant, and the problem of selection of working fluid is in the search for compromise based on the priorities in the field of efficiency, safety, and ecology criteria of a binary power plant. It is proposed in the investigations on the working fluid selection of the binary plant to use the plotting method of multiaxis complex diagrams of relative parameters and characteristic of binary power plants. Some examples of plotting and analyzing these diagrams intended to choose the working fluid provided that the efficiency of geothermal brine is taken as main priority.

  13. Experiments on Quantum Hall Topological Phases in Ultra Low Temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Du, Rui-Rui [Rice Univ., Houston, TX (United States). Dept. of Physics and Astronomy

    2015-02-14

    This project is to cool electrons in semiconductors to extremely low temperatures and to study new states of matter formed by low-dimensional electrons (or holes). At such low temperatures (and with an intense magnetic field), electronic behavior differs completely from ordinary ones observed at room temperatures or regular low temperature. Studies of electrons at such low temperatures would open the door for fundamental discoveries in condensed matter physics. Present studies have been focus on topological phases in the fractional quantum Hall effect in GaAs/AlGaAs semiconductor heterostructures, and the newly discovered (by this group) quantum spin Hall effect in InAs/GaSb materials. This project consists of the following components: 1) Development of efficient sample cooling techniques and electron thermometry: Our goal is to reach 1 mK electron temperature and reasonable determination of electron temperature; 2) Experiments at ultra-low temperatures: Our goal is to understand the energy scale of competing quantum phases, by measuring the temperature-dependence of transport features. Focus will be placed on such issues as the energy gap of the 5/2 state, and those of 12/5 (and possible 13/5); resistive signature of instability near 1/2 at ultra-low temperatures; 3) Measurement of the 5/2 gaps in the limit of small or large Zeeman energies: Our goal is to gain physics insight of 5/2 state at limiting experimental parameters, especially those properties concerning the spin polarization; 4) Experiments on tuning the electron-electron interaction in a screened quantum Hall system: Our goal is to gain understanding of the formation of paired fractional quantum Hall state as the interaction pseudo-potential is being modified by a nearby screening electron layer; 5) Experiments on the quantized helical edge states under a strong magnetic field and ultralow temperatures: our goal is to investigate both the bulk and edge states in a quantum spin Hall insulator under time

  14. Outstanding issues for new geothermal resource assessments

    Science.gov (United States)

    Williams, C.F.; Reed, M.J.

    2005-01-01

    A critical question for the future energy policy of the United States is the extent to which geothermal resources can contribute to an ever-increasing demand for electricity. Electric power production from geothermal sources exceeds that from wind and solar combined, yet the installed capacity falls far short of the geothermal resource base characterized in past assessments, even though the estimated size of the resource in six assessments completed in the past 35 years varies by thousands of Megawatts-electrical (MWe). The U. S. Geological Survey (USGS) is working closely with the Department of Energy's (DOE) Geothermal Research Program and other geothermal organizations on a three-year effort to produce an updated assessment of available geothermal resources. The new assessment will introduce significant changes in the models for geothermal energy recovery factors, estimates of reservoir permeability, limits to temperatures and depths for electric power production, and include the potential impact of evolving Enhanced (or Engineered) Geothermal Systems (EGS) technology.

  15. Imperial County geothermal development annual meeting: summary

    Energy Technology Data Exchange (ETDEWEB)

    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)

  16. Geothermal Potential of the Siǧacik Gulf (Seferihisar) and Preliminary investigations with Seismic and Magnetic Surveys

    Science.gov (United States)

    Bakak, Özde; Özel, Erdeniz; Ergün, Mustafa

    2015-04-01

    The Aegean region, including both W. Turkey and Central Greece, is one of the world's most rapidly-deforming regions of continental crust and has a seismic rate is exceptional on a world scale. SW Turkey is one of the most rapidly extending regions in the world where the extension appears to have commenced in middle or late Miocene time. Paleomagnetic work in W Turkey and Aegean islands has revealed the horizontal rotation of some crustal blocks. In W Turkey clockwise rotation on Karaburun peninsula west of Izmir by 44° in the last few Ma is detected, and anticlockwise rotation of 37° for the Seferihisar region. The area of W Turkey and the Aegean islands has very strong geothermal gradient in the world scale. Sığacık Gulf is located on south of Karaburun Peninsula, and it is restricted by two important ridges as Karaburun and Seferihisar Ridges. Recent geological and geophysical studies suggested that this area is both E-W trending normal and NE-SW trending strike-slip faulting caused deformation. The Seferihisar earthquake series were occurred here during 17-20 October 2005. For investigation of geothermal potential and hot water outlets on the seafloor, shallow seismic and magnetic surveys are preferred, which were carried out onboard Dokuz Eylül-1 vessel belongs to Dokuz Eylül University, in 2011. Approximately 250km seismic reflection data was collected along 27 lines. During seismic method used Sparker system which has 1 channel and 12 hydrophone with 17 m long streamer, as a seismic source used SIG Seismic Marine ELC 80 (4 kV & 3.2 KV DC). Seismic data processing (band pass filter, bottom mute, top mute, true amplitude recovery, time migration) was made using Promax program in the Seismic Laboratory in the Institute of Marine Science and Technology. The basement topography map was prepared using Kingdom Suite program drawing seabed line on these sections. Sea floor topography changes between 30-120 m, and this increases towards Ikaria Basin

  17. Low temperature photoresponse of monolayer tungsten disulphide

    Directory of Open Access Journals (Sweden)

    Bingchen Cao

    2014-11-01

    Full Text Available High photoresponse can be achieved in monolayers of transition metal dichalcogenides. However, the response times are inconveniently limited by defects. Here, we report low temperature photoresponse of monolayer tungsten disulphide prepared by exfoliation and chemical vapour deposition (CVD method. The exfoliated device exhibits n-type behaviour; while the CVD device exhibits intrinsic behaviour. In off state, the CVD device has four times larger ratio of photoresponse for laser on/off and photoresponse decay–rise times are 0.1 s (limited by our setup, while the exfoliated device has few seconds. These findings are discussed in terms of charge trapping and localization.

  18. Mechanism of bacterial adaptation to low temperature

    Indian Academy of Sciences (India)

    M K Chattopadhyay

    2006-03-01

    Survival of bacteria at low temperatures provokes scientific interest because of several reasons. Investigations in this area promise insight into one of the mysteries of life science – namely, how the machinery of life operates at extreme environments. Knowledge obtained from these studies is likely to be useful in controlling pathogenic bacteria, which survive and thrive in cold-stored food materials. The outcome of these studies may also help us to explore the possibilities of existence of life in distant frozen planets and their satellites.

  19. Low-temperature heat transfer in nanowires.

    Science.gov (United States)

    Glavin, B A

    2001-05-07

    A new regime of low-temperature heat transfer in suspended nanowires is predicted. It takes place when (i) only "acoustic" phonon modes of the wire are thermally populated and (ii) phonons are subject to the effective elastic scattering. Qualitatively, the main peculiarities of heat transfer originate due to the appearance of the flexural modes with high density of states in the wire phonon spectrum. They give rise to the T(1/2) temperature dependence of the wire thermal conductance. Experimental situations where the new regime is likely to be detected are discussed.

  20. Low temperature waste form process intensification

    Energy Technology Data Exchange (ETDEWEB)

    Fox, K. M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Cozzi, A. D. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hansen, E. K. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hill, K. A. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-09-30

    This study successfully demonstrated process intensification of low temperature waste form production. Modifications were made to the dry blend composition to enable a 50% increase in waste concentration, thus allowing for a significant reduction in disposal volume and associated costs. Properties measurements showed that the advanced waste form can be produced using existing equipment and processes. Performance of the waste form was equivalent or better than the current baseline, with approximately double the amount of waste incorporation. The results demonstrate the feasibility of significantly accelerating low level waste immobilization missions across the DOE complex and at environmental remediation sites worldwide.

  1. Investigations of Low Temperature Time Dependent Cracking

    Energy Technology Data Exchange (ETDEWEB)

    Van der Sluys, W A; Robitz, E S; Young, B A; Bloom, J

    2002-09-30

    The objective of this project was to investigate metallurgical and mechanical phenomena associated with time dependent cracking of cold bent carbon steel piping at temperatures between 327 C and 360 C. Boiler piping failures have demonstrated that understanding the fundamental metallurgical and mechanical parameters controlling these failures is insufficient to eliminate it from the field. The results of the project consisted of the development of a testing methodology to reproduce low temperature time dependent cracking in laboratory specimens. This methodology was used to evaluate the cracking resistance of candidate heats in order to identify the factors that enhance cracking sensitivity. The resultant data was integrated into current available life prediction tools.

  2. Low temperature vibrational spectroscopy. I. Hexachlorotellurates

    DEFF Research Database (Denmark)

    Berg, Rolf W.; Poulsen, Finn Willy; Bjerrum, Niels

    1977-01-01

    frequency lattice modes were observed and interpreted in terms of a phase transition near 165 K, similar to transitions in other K2[MX6] salts. The cubic tetramethylammonium hexachlorotellurate salt undergoes a phase transition of supposed first order at a temperature near 110 K, corresponding...... to transitions known in analogous uranium and tin compounds. Possible reasons for the transitions are discussed. In the low temperature phases the nu4 and nu6 bendings of [TeCl6]2− have been identified with bands near ~130 and ~110 cm−1. No evidence seemed to favor any stereochemical distortion due to the lone...

  3. Mineralogical-chemical composition and environmental risk potential of pond sediments at the geothermal field of Los Azufres, Mexico

    Science.gov (United States)

    Birkle, P.; Merkel, B.

    2002-01-01

    Since 1982, estimated amounts of 9,400 t, 15,000 kg, 720 kg and 105 kg of Si, Fe, As and Cs respectively have accumulated at the bottom of 18 evaporation ponds as part of the geothermal production cycle at Los Azufres. This accumulation is caused by precipitation of brine solutes during the evaporation of 10% of the total pond water volume before its re-injection into the reservoir. Extraction experiments with pond precipitates and geochemical simulations with the PHREEQC program indicate the high solubility of most precipitates under natural environmental conditions. The comparisons with the primary brine composition indicate that less than 1% of most dissolved brine solutes, except for Co, Cu, Mn, Pb, Ag, Fe and Si, are accumulated at the pond bottom. Arsenic has maximum values of 160 mg/kg in the pond sediments, and Mo, Hg and Tl also exceed international environmental standards for contaminated soils. Elevated concentrations and the mobility potential of several metals and non-metals require the application of remediation techniques for the final disposal of the sediments in the future.

  4. Geothermal progress monitor report No. 6

    Energy Technology Data Exchange (ETDEWEB)

    1982-06-01

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

  5. Evaluation of geothermal potential of Rio Grande rift and Basin and Range province, New Mexico. Final technical report, January 1, 1977-May 31, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Callender, J.F.

    1985-04-01

    A study was made of the geological, geochemical and geophysical characteristics of potential geothermal areas in the Rio Grande rift and Basin and Range province of New Mexico. Both regional and site-specific information is presented. Data was collected by: (1) reconnaissance and detailed geologic mapping, emphasizing Neogene stratigraphy and structure; (2) petrologic studies of Neogene igneous rocks; (3) radiometric age-dating; (4) geochemical surveying, including regional and site-specific water chemistry, stable isotopic analyses of thermal waters, whole-rock and mineral isotopic studies, and whole-rock chemical analyses; and (5) detailed geophysical surveys, using electrical, gravity and magnetic techniques, with electrical resistivity playing a major role. Regional geochemical water studies were conducted for the whole state. Integrated site-specific studies included the Animas Valley, Las Cruces area (Radium Springs and Las Alturas Estates), Truth or Consequences region, the Albuquerque basin, the San Ysidro area, and the Abiquiu-Ojo Caliente region. The Animas Valley and Las Cruces areas have the most significant geothermal potential of the areas studied. The Truth or Consequences and Albuquerque areas need further study. The San Ysidro and Abiquiu-Ojo Caliente regions have less significant geothermal potential. 78 figs., 16 tabs.

  6. Inert Anode Life in Low Temperature Reduction Process

    Energy Technology Data Exchange (ETDEWEB)

    Bradford, Donald R.

    2005-06-30

    The production of aluminum metal by low temperature electrolysis utilizing metal non-consumable anodes and ceramic cathodes was extensively investigated. Tests were performed with traditional sodium fluoride--aluminum fluoride composition electrolytes, potassium fluoride-- aluminum fluoride electrolytes, and potassium fluoride--sodium fluoride--aluminum fluoride electrolytes. All of the Essential First-Tier Requirements of the joint DOE-Aluminum Industry Inert Anode Road Map were achieved and those items yet to be resolved for commercialization of this technology were identified. Methods for the fabrication and welding of metal alloy anodes were developed and tested. The potential savings of energy and energy costs were determined and potential environmental benefits verified.

  7. The 2017 Plasma Roadmap: Low temperature plasma science and technology

    Science.gov (United States)

    Adamovich, I.; Baalrud, S. D.; Bogaerts, A.; Bruggeman, P. J.; Cappelli, M.; Colombo, V.; Czarnetzki, U.; Ebert, U.; Eden, J. G.; Favia, P.; Graves, D. B.; Hamaguchi, S.; Hieftje, G.; Hori, M.; Kaganovich, I. D.; Kortshagen, U.; Kushner, M. J.; Mason, N. J.; Mazouffre, S.; Mededovic Thagard, S.; Metelmann, H.-R.; Mizuno, A.; Moreau, E.; Murphy, A. B.; Niemira, B. A.; Oehrlein, G. S.; Petrovic, Z. Lj; Pitchford, L. C.; Pu, Y.-K.; Rauf, S.; Sakai, O.; Samukawa, S.; Starikovskaia, S.; Tennyson, J.; Terashima, K.; Turner, M. M.; van de Sanden, M. C. M.; Vardelle, A.

    2017-08-01

    Journal of Physics D: Applied Physics published the first Plasma Roadmap in 2012 consisting of the individual perspectives of 16 leading experts in the various sub-fields of low temperature plasma science and technology. The 2017 Plasma Roadmap is the first update of a planned series of periodic updates of the Plasma Roadmap. The continuously growing interdisciplinary nature of the low temperature plasma field and its equally broad range of applications are making it increasingly difficult to identify major challenges that encompass all of the many sub-fields and applications. This intellectual diversity is ultimately a strength of the field. The current state of the art for the 19 sub-fields addressed in this roadmap demonstrates the enviable track record of the low temperature plasma field in the development of plasmas as an enabling technology for a vast range of technologies that underpin our modern society. At the same time, the many important scientific and technological challenges shared in this roadmap show that the path forward is not only scientifically rich but has the potential to make wide and far reaching contributions to many societal challenges.

  8. Theoretical kinetic study of the low temperature oxidation of ethanol

    CERN Document Server

    Fournet, René; Bounaceur, Roda; Molière, Michel

    2009-01-01

    In order to improve the understanding of the low temperature combustion of ethanol, high-level ab initio calculations were performed for elementary reactions involving hydroxyethylperoxy radicals. These radicals come from the addition of hydroxethyl radicals (?CH3CHOH and ?CH2CH2OH) on oxygen molecule. Unimolecular reactions involving hydroxyethylperoxy radicals and their radical products were studied at the CBS-QB3 level of theory. The results allowed to highlight the principal ways of decomposition of these radicals. Calculations of potential energy surfaces showed that the principal channels lead to the formation of HO2 radicals which can be considered, at low temperature, as slightly reactive. However, in the case of CH3CH(OOH)O? radicals, a route of decomposition yields H atom and formic peracid, which is a branching agent that can strongly enhance the reactivity of ethanol in low temperature oxidation. In addition to these analyses, high-pressure limit rate constants were derived in the temperature rang...

  9. Low-temperature photoluminescence in self-assembled diphenylalanine microtubes

    Energy Technology Data Exchange (ETDEWEB)

    Nikitin, T. [Institute of Natural Sciences, Ural Federal University, 620000 Ekaterinburg (Russian Federation); Kopyl, S. [Physics Department & CICECO – Materials Institute of Aveiro, University of Aveiro, 3810-193 Aveiro (Portugal); Shur, V.Ya. [Institute of Natural Sciences, Ural Federal University, 620000 Ekaterinburg (Russian Federation); Kopelevich, Y.V., E-mail: kopel@ifi.unicamp.br [Instituto de Fisica, UNICAMP, Campinas, São Paulo 13083-859 (Brazil); Kholkin, A.L., E-mail: kholkin@gmail.com [Institute of Natural Sciences, Ural Federal University, 620000 Ekaterinburg (Russian Federation); Physics Department & CICECO – Materials Institute of Aveiro, University of Aveiro, 3810-193 Aveiro (Portugal)

    2016-04-22

    Bioinspired self-assembled structures are increasingly important for a variety of applications ranging from drug delivery to electronic and energy harvesting devices. An important class of these structures is diphenylalanine microtubes which are potentially important for optical applications including light emitting diodes and optical biomarkers. In this work we present the data on their photoluminescent properties at low temperatures (down to 12 K) and discuss the origin of the emission in the near ultraviolet (UV) range seen earlier in a number of reports. UV luminescence increases with decreasing temperature and exhibits several equidistant lines that are assigned to zero-phonon exciton emission line and its phonon replicas. We infer that the exciton is localized on the defect sites and significant luminescence decay is due to thermal quenching arising from the carrier excitation from these defects and non-radiative recombination. - Highlights: • Low-temperature luminescence is studied in bioinspired self-assembled FF peptide microtubes. • The mechanism of the optical emission is assigned to the luminescence of excitonic states localized at defects. • Luminescence in FF microtubes can be used as an absolute temperature probe at low temperature.

  10. Antimisting kerosene: Low temperature degradation and blending

    Science.gov (United States)

    Yavrouian, A.; Parikh, P.; Sarohia, V.

    1988-01-01

    The inline filtration characteristics of freshly blended and degraded antimisting fuels (AMK) at low temperature are examined. A needle valve degrader was modified to include partial recirculation of degraded fuel and heat addition in the bypass loop. A pressure drop across the needle valve of up to 4,000 psi was used. The pressure drop across a 325 mesh filter screen placed inline with the degrader and directly downstream of the needle valve was measured as a function of time for different values of pressure drop across the needle valve. A volume flux of 1 gpm/sq in was employed based on the frontal area of the screen. It was found that, at ambient temperatures, freshly blended AMK fuel could be degraded using a single pass degradation at 4,000 psi pressure drop across the needle valve to give acceptable filterability performance. At fuel temperatures below -20 C, degradation becomes increasingly difficult and a single pass technique results in unacceptable filtration performance. Recirculation of a fraction of the degraded fuel and heat addition in the bypass loop improved low temperature degradation performance. The problem is addressed of blending the AMK additive with Jet A at various base fuel temperatures.

  11. Low temperature operation and exhaust emission

    Energy Technology Data Exchange (ETDEWEB)

    Laurikko, J.

    1987-01-01

    Ambient temperature has the greatest effect on the exhaust emissions of internal combustion engines during the initial cold star and before the engine is fully warmed-up. Fuel evaporation is poor in a cold engine and the fuel-air mixture must be made richer to ensure that the engine weill start and be driveable. However, the combustion of a rich fuel-air mixture is incomplete because of the lack of oxygen, and the exhaust gases will contain an excessive amount of carbon monoxide (CO). The formation of nitrogen oxides (NO/sub x/) in a combustion engine is tied to high temperatures and oxygen concentrations. The conditions in a non-warmed engine using a rich fuel-air mixture are unfavourable for the formation of NO/sub x/ and the emission of NO/sub x/ may even diminish with falling ambient temperature. When the engine has reached its normal operating temperature the exhaust emissions are usually independent of the ambient temperature if the engine is equipped with intake air preheating that is sufficiently powerful. The reduction efficiency of a catalytic converter mainly depends on its operation temperature. Continuous operation at low temperatures may cause rapid poisoning of the converter. At low temperatures, carbon and other particles that do not burn collect on the active surface of the converter reducing its effectiveness.

  12. Low Temperature Spin Structure of Gadolinium Titanate

    Science.gov (United States)

    Javanparast, Behnam; McClarty, Paul; Gingras, Michel

    2012-02-01

    Many rare earth pyrochlore oxides exhibit exotic spin configurations at low temperatures due to frustration. The nearest neighbor coupling between spins on the corner-sharing tetrahedral network generate geometrical magnetic frustration. Among these materials, gadolinium titanate (Gd2Ti2O7) is of particular interest. Its low temperature ordered phases are not yet understood theoretically. Bulk thermal measurements such as specific heat and magnetic susceptibility measurements find two phase transitions in zero external field, in agreement with simple mean field calculations. However, recent neutron scattering experiments suggest a so-called 4-k spin structure for intermediate phase and a so called canted 4-k structure for lower temperature phase that does not agree with either mean-field theory or Monte Carlo simulation which find the 1-k state and Palmer-Chalker state respectively as the lowest free energy configuration for those phases. In our work, we study the 4-k structure in detail and present a new phase diagram for dipolar Heisenberg spins on a pyrochlore lattice, certain portions of which describe gadolinium titanate.

  13. Extreme low temperature tolerance in woody plants

    Directory of Open Access Journals (Sweden)

    George Richard Strimbeck

    2015-10-01

    Full Text Available Woody plants in boreal to arctic environments and high mountains survive prolonged exposure to temperatures below -40˚C and minimum temperatures below -60˚C, and laboratory tests show that many of these species can also survive immersion in liquid nitrogen at -196˚C. Studies of biochemical changes that occur during acclimation, including recent proteomic and metabolomic studies, have identified changes in carbohydrate and compatible solute concentrations, membrane lipid composition, and proteins, notably dehydrins, that may have important roles in survival at extreme low temperature. Consideration of the biophysical mechanisms of membrane stress and strain lead to the following hypotheses for cellular and molecular mechanisms of survival at extreme low temperature: 1. Changes in lipid composition stabilize membranes at temperatures above the lipid phase transition temperature (-20 to 30˚C, preventing phase changes that result in irreversible injury. 2. High concentrations of oligosaccharides promote vitrification or high viscosity in the cytoplasm in freeze-dehydrated cells, which would prevent deleterious interactions between membranes. 3. Dehydrins bind membranes and further promote vitrification or act stearically to prevent membrane-membrane interactions.

  14. Low-temperature ashing of Bulgarian lignites

    Energy Technology Data Exchange (ETDEWEB)

    Douchanov, D.; Minkova, V.; Martinez-Alonso, A.; Palacios, J.M.; Tascon, J.M.D. [Bulgarian Academy of Sciences, Sofia (Bulgaria). Inst. of Organic Chemistry

    1993-12-01

    The characterization of mineral components of coals requires their isolation from organic matter, which would otherwise interfere with phase identification by means of physico-chemical techniques. Low-temperature ashing (LTA) using a cool oxygen plasma is a prospective method to oxidise coal organic matter at low temperatures while keeping the mineral constituents unaltered. In this work the authors used a microwave-excited plasma apparatus for the LTA treatment of lignite samples from the Maritza-Iztok (M-1-1; M-1-2) and Elhovo basins. Minerals were characterised in the LTA residues using FT-IR spectroscopy, X-ray diffraction and scanning electron microscopy combined with energy-dispersive X-ray microanalysis. The advantages and disadvantages of the LTA method are discussed. Results indicate that LTA performs well for the isolation of mineral matter, the ensuing methodology being adequate for the characterisation of Bulgarian lignites. The same mineral constituents (principally clay minerals, quartz, pyrite and carbonates) were identified in all the three studied samples, differences being mainly in their particle size, degree of crystallinity and distribution in the organic matter of coals. 43 refs., 5 figs., 3 tabs.

  15. The Low Temperature Microgravity Physics Experiments Project

    Science.gov (United States)

    Holmes, Warren; Lai, Anthony; Croonquist, Arvid; Chui, Talso; Eraker, J. H.; Abbott, Randy; Mills, Gary; Mohl, James; Craig, James; Balachandra, Balu; hide

    2000-01-01

    The Low Temperature Microgravity Physics Facility (LTMPF) is being developed by NASA to provide long duration low temperature and microgravity environment on the International Space Station (ISS) for performing fundamental physics investigations. Currently, six experiments have been selected for flight definition studies. More will be selected in a two-year cycle, through NASA Research Announcement. This program is managed under the Low Temperature Microgravity Physics Experiments Project Office at the Jet Propulsion Laboratory. The facility is being designed to launch and returned to earth on a variety of vehicles including the HII-A and the space shuttle. On orbit, the facility will be connected to the Exposed Facility on the Japanese Experiment Module, Kibo. Features of the facility include a cryostat capable of maintaining super-fluid helium at a temperature of 1.4 K for 5 months, resistance thermometer bridges, multi-stage thermal isolation system, thermometers capable of pico-Kelvin resolution, DC SQUID magnetometers, passive vibration isolation, and magnetic shields with a shielding factor of 80dB. The electronics and software architecture incorporates two VME buses run using the VxWorks operating system. Technically challenging areas in the design effort include the following: 1) A long cryogen life that survives several launch and test cycles without the need to replace support straps for the helium tank. 2) The minimization of heat generation in the sample stage caused by launch vibration 3) The design of compact and lightweight DC SQUID electronics. 4) The minimization of RF interference for the measurement of heat at pico-Watt level. 5) Light weighting of the magnetic shields. 6) Implementation of a modular and flexible electronics and software architecture. The first launch is scheduled for mid-2003, on an H-IIA Rocket Transfer Vehicle, out of the Tanegashima Space Center of Japan. Two identical facilities will be built. While one facility is onboard

  16. 低温包埋渗铝及其在石油管材防腐蚀应用中的研究进展%Research Progress of Low-temperature Pack Aluminizing and Its Potential Application on Oil-casing Steel and Pipeline Steel

    Institute of Scientific and Technical Information of China (English)

    黄敏; 王宇

    2012-01-01

    慨述了钢基表面低温包埋渗铝的原理,分析了通过添加稀土元素、调整活性剂种类、在渗剂中添加合金、表面机械能助渗、基材表面自身纳米化预处理等实现低温渗铝的研究现状和优缺点.同时,针对高力学性能石油管材,提出了将表面自身纳米化技术与含锌的低温渗剂相结合的石油管材表面低温复合包埋渗铝技术,并对该技术在石油管材耐腐蚀保护方面的应用进行了展望,认为复合低温包埋渗铝技术在石油管材耐腐蚀处理中的应用具有广阔前景.%The main principle of low-temperature pack aluminizing of carbon steel was described. The present research situation and different characteristics of low-temperature pack aluminizing processing were analyzed by the addition of rare earth element, the adjustment of active agent type, the addition of alloy dement, the assistance of surface mechanical energy and the surface selmanocrystallization treatment of steel substrate. For oil-casing steel and pipeline steel with high mechanical properties, a combined low-temperature pack aluminizing for oil-casing steel and pipeline steel with surface nano-crystallization structure packed by powdeT with the addition of zinc was proposed. On the basis pf the potential corrosion resistance improvement of aluminized oil-casing steel and pipeline steel by combined low-temperature pack aluminizing, it can be concluded that the as-mentioned combined low-temperature pack aluminizing is hopeful for the wide application of aluminizing for the corrosion protection of oil-casing steel and pipeline steel.

  17. Low Temperature Waste Immobilization Testing Vol. I

    Energy Technology Data Exchange (ETDEWEB)

    Russell, Renee L.; Schweiger, Michael J.; Westsik, Joseph H.; Hrma, Pavel R.; Smith, D. E.; Gallegos, Autumn B.; Telander, Monty R.; Pitman, Stan G.

    2006-09-14

    The Pacific Northwest National Laboratory (PNNL) is evaluating low-temperature technologies to immobilize mixed radioactive and hazardous waste. Three waste forms—alkali-aluminosilicate hydroceramic cement, “Ceramicrete” phosphate-bonded ceramic, and “DuraLith” alkali-aluminosilicate geopolymer—were selected through a competitive solicitation for fabrication and characterization of waste-form properties. The three contractors prepared their respective waste forms using simulants of a Hanford secondary waste and Idaho sodium bearing waste provided by PNNL and characterized their waste forms with respect to the Toxicity Characteristic Leaching Procedure (TCLP) and compressive strength. The contractors sent specimens to PNNL, and PNNL then conducted durability (American National Standards Institute/American Nuclear Society [ANSI/ANS] 16.1 Leachability Index [LI] and modified Product Consistency Test [PCT]) and compressive strength testing (both irradiated and as-received samples). This report presents the results of these characterization tests.

  18. Low temperature thermal-energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Segaser, C.S.; Christian, J.E.

    1979-03-01

    This report evaluates currently available techniques and estimated costs of low temperature thermal energy storage (TES) devices applicable to Integrated Community Energy Systems (ICES) installations serving communities ranging in size from approximately 3000 (characterized by an electrical load requirement of 2 MWe) to about 100,000 population (characterized by an electrical load requirement of 100 MWe). Thermal energy in the form of either hotness or coldness can be stored in a variety of media as sensible heat by virtue of a change in temperature of the material, or as latent heat of fusion in which the material changes from the liquid phase to the solid phase at essentially a constant temperature. Both types of material are considered for TES in ICES applications.

  19. Performance of MPPC at low temperature

    Institute of Scientific and Technical Information of China (English)

    AN Zheng-Hua; XUE Zhen; SUN Xi-Lei; L(ü) QI-Wen; ZHANG Ai-Wu; NING Fei-Peng; ZHOU Li; SUN Li-Jun; GE Yong-Shuai; LIU Ying-Biao; WU Chong; L(U) Jun-Guang; SHI Feng; HU Tao; CAI Xiao; YU Bo-Xiang; FANG Jian; XIE Yu-Guang; WANG Zhi-Gang

    2012-01-01

    The performance of a MultiPixel Photon Counter (MPPC) from room to liquid nitrogen temperatures were studied.The gain,the noise rate and bias voltage of the MPPC as a function of temperature were obtained.The experimental results show that the MPPC can work at low temperatures.At nearly liquid nitrogen temperatures,the gain of the MPPC drops obviously to 35% and the bias voltage drops about 9 V compared with that at room temperature.The thermal noise rate from 106 Hz/mm at room temperature drops abruptly to 0 Hz/mm at -100 ℃.The optimized operation point can be acquired by the experiment.

  20. Low temperature properties of erbium in gold

    Energy Technology Data Exchange (ETDEWEB)

    Fleischmann, A.; Schoenefeld, J.; Sollner, J.; Enss, C.; Adams, J.S.; Bandler, S.R.; Kim, Y.H.; Seidel, G.M.

    2000-01-01

    The properties of dilute alloys of Er in Au have been studied, principally below 100 mK, in connection with the use of this system in thermometry and in microcalorimetry for particle detection. Measurements are reported of (1) the magnetization at high temperatures and high field, (2) the magnetization in low fields with temperatures extending down to 0.1 mK, and (3) the heat capacity as a function of temperature and field at low temperatures. These measurements are analyzed to provide information of several properties of the Er{sup 3+} ion in the Au lattice, in particular, the crystal field parameters, the exchange interaction of the 4f electrons with the conduction electrons, and the spin glass freezing temperature.

  1. GEOTHERMICS GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    <正>20101802 Fang Bin (China University of Geosciences,Beijing 100083,China);Yang Yunjun Characteristics and Resource Evaluation of the Jiwa Geothermal Field in Central Qiangtang,Northern Tibet,China (Geological Bulletin of China,ISSN1671-

  2. GEOTHERMICS GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>20112453 Li Qing (First Design and Research Institute,Ministry of Mechanical Industry, Bengbu 233000, China); Li Yixiang Application of Shallow Geothermal Energy Resources in the Hefei Area(Geology

  3. Geothermal Websites

    Energy Technology Data Exchange (ETDEWEB)

    Boyd, Tonya

    2005-03-01

    The Internet has become such an important part of our every day life. It can be used to correspond with people across the world, a lot faster than to send a letter in the mail. The Internet has a wealth of information that is available to anybody just by searching for it. Sometimes you get more information than you ever wanted to know and sometimes you can’t find any information. This paper will only cover a small portion of the websites and their links that have geothermal information concerning reservoir engineering, enhanced geothermal systems, hot dry rock and other aspects of geothermal. Some of the websites below are located in the US others international, such as, geothermal associations, and websites where you can access publications. Most of the websites listed below also have links to other websites for even more information.

  4. Ultra-low temperature MAS-DNP

    Science.gov (United States)

    Lee, Daniel; Bouleau, Eric; Saint-Bonnet, Pierre; Hediger, Sabine; De Paëpe, Gaël

    2016-03-01

    Since the infancy of NMR spectroscopy, sensitivity and resolution have been the limiting factors of the technique. Regular essential developments on this front have led to the widely applicable, versatile, and powerful spectroscopy that we know today. However, the Holy Grail of ultimate sensitivity and resolution is not yet reached, and technical improvements are still ongoing. Hence, high-field dynamic nuclear polarization (DNP) making use of high-frequency, high-power microwave irradiation of electron spins has become very promising in combination with magic angle sample spinning (MAS) solid-state NMR experiments. This is because it leads to a transfer of the much larger polarization of these electron spins under suitable irradiation to surrounding nuclei, greatly increasing NMR sensitivity. Currently, this boom in MAS-DNP is mainly performed at minimum sample temperatures of about 100 K, using cold nitrogen gas to pneumatically spin and cool the sample. This Perspective deals with the desire to improve further the sensitivity and resolution by providing "ultra"-low temperatures for MAS-DNP, using cryogenic helium gas. Different designs on how this technological challenge has been overcome are described. It is shown that stable and fast spinning can be attained for sample temperatures down to 30 K using a large cryostat developed in our laboratory. Using this cryostat to cool a closed-loop of helium gas brings the additional advantage of sample spinning frequencies that can greatly surpass those achievable with nitrogen gas, due to the differing fluidic properties of these two gases. It is shown that using ultra-low temperatures for MAS-DNP results in substantial experimental sensitivity enhancements and according time-savings. Access to this temperature range is demonstrated to be both viable and highly pertinent.

  5. Low-temperature gas from marine shales

    Directory of Open Access Journals (Sweden)

    Jarvie Daniel M

    2009-02-01

    Full Text Available Abstract Thermal cracking of kerogens and bitumens is widely accepted as the major source of natural gas (thermal gas. Decomposition is believed to occur at high temperatures, between 100 and 200°C in the subsurface and generally above 300°C in the laboratory. Although there are examples of gas deposits possibly generated at lower temperatures, and reports of gas generation over long periods of time at 100°C, robust gas generation below 100°C under ordinary laboratory conditions is unprecedented. Here we report gas generation under anoxic helium flow at temperatures 300° below thermal cracking temperatures. Gas is generated discontinuously, in distinct aperiodic episodes of near equal intensity. In one three-hour episode at 50°C, six percent of the hydrocarbons (kerogen & bitumen in a Mississippian marine shale decomposed to gas (C1–C5. The same shale generated 72% less gas with helium flow containing 10 ppm O2 and the two gases were compositionally distinct. In sequential isothermal heating cycles (~1 hour, nearly five times more gas was generated at 50°C (57.4 μg C1–C5/g rock than at 350°C by thermal cracking (12 μg C1–C5/g rock. The position that natural gas forms only at high temperatures over geologic time is based largely on pyrolysis experiments under oxic conditions and temperatures where low-temperature gas generation could be suppressed. Our results indicate two paths to gas, a high-temperature thermal path, and a low-temperature catalytic path proceeding 300° below the thermal path. It redefines the time-temperature dimensions of gas habitats and opens the possibility of gas generation at subsurface temperatures previously thought impossible.

  6. Geothermal Energy in China: Status and Problems

    Institute of Scientific and Technical Information of China (English)

    Hu Ke; Yang Deming

    2000-01-01

    The application of geothermal energy in China has a long history. From the 70's last century, the research and development of geothermal in the world has been greatly advanced, and the Chinese geologists have finished the fundmental work for geothermal prospecting. The application technology is much behind in china. With the fast growing of national economy, the public, as well as the government recognizes the importance of clean and renewable energy, large scale development of geothermal energy is on the gate in China. This paper gives an outline of the geothermal potentials in china, and points out the problems and technical needs in the research and development in the near future.

  7. Protecting geothermal operations with rupture disks

    Energy Technology Data Exchange (ETDEWEB)

    Porter, D.W.

    1983-02-01

    Potential rupture disk applications in geothermal operations are reviewed. Several wells manifolded together, to form the geothermal feed, cause erratic pressure. Rupture disks are used for relief. Flash tanks are equipped with rupture disks. Brine separators, heat exchanger shells, and turbine casings are protected by rupture disks. An analysis of geothermal steam will determine the rupture disk metal. Reverse Buckling disks are recommended over tension loaded disks for dealing with geothermal pressure cycling. Erratic temperature suggests that metals which retain tensile strength with temperature be used (Inconel is mentioned). In summary, geothermal projects represent an excellent rupture disk market.

  8. The low-temperature method for study of coniferous tissues in the environmental scanning electron microscope.

    Science.gov (United States)

    Neděla, Vilém; Tihlaříková, Eva; Hřib, Jiří

    2015-01-01

    The use of non-standard low-temperature conditions in environmental scanning electron microscopy might be promising for the observation of coniferous tissues in their native state. This study is aimed to analyse and evaluate the method based on the principle of low-temperature sample stabilization. We demonstrate that the upper mucous layer is sublimed and a microstructure of the sample surface can be observed with higher resolution at lower gas pressure conditions, thanks to a low-temperature method. An influence of the low-temperature method on sample stability was also studied. The results indicate that high-moisture conditions are not suitable for this method and often cause the collapse of samples. The potential improvement of stability to beam damage has been demonstrated by long-time observation at different operation parameters. We finally show high applicability of the low-temperature method on different types of conifers and Oxalis acetosella. © 2014 Wiley Periodicals, Inc.

  9. Mapping of low temperature heat sources in Denmark

    DEFF Research Database (Denmark)

    Bühler, Fabian; Holm, Fridolin Müller; Huang, Baijia

    2015-01-01

    of those heat sources feasible. In this work a mapping of those heat sources is performed to gain an overview of the potential amount of waste heat and natural heat sources in Denmark. The energy potentials are mapped together with the temperature ranges at which the heat is available and the exergy...... content of the heat. The mapping is based on data and literature primarily published by Statistics Denmark and the Danish Energy Agency, as well as interviews with specialists and engineering estimates. The results indicate that up to 13 % of the energy input to the analysed sectors is available as waste...... and deep geothermal energy. The theoretical solar thermal potential alone would be above 500 PJ per year. For the development of advanced thermodynamic cycles for the integration of heat sources in the Danish energy system, several areas of interest are determined. In the maritime transport sector a high...

  10. GEOTHERMICS GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    20151782 Ding Zhaoqin(Institute of Geophysical Exploration of Jilin Province,Changchun130012,China);Xu Zhihe The Possibility of Structure and Occurrence Geothermal Resources in Dunhua-Mishan Fault Zone(Huinan Section)(Jilin Geology,ISSN1001-2427,CN22-1099/P,33(2),2014,p.98-102,5illus.,1table,4refs.)Key words:geothermal resources,fracture

  11. 2008 Geothermal Technologies Market Report

    Energy Technology Data Exchange (ETDEWEB)

    Jonathan Cross

    2009-07-01

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

  12. Combination of Well-Logging Temperature and Thermal Remote Sensing for Characterization of Geothermal Resources in Hokkaido, Northern Japan

    Directory of Open Access Journals (Sweden)

    Bingwei Tian

    2015-03-01

    Full Text Available Geothermal resources have become an increasingly important source of renewable energy for electrical power generation worldwide. Combined Three Dimension (3D Subsurface Temperature (SST and Land Surface Temperature (LST measurements are essential for accurate assessment of geothermal resources. In this study, subsurface and surface temperature distributions were combined using a dataset comprised of well logs and Thermal Infrared Remote sensing (TIR images from Hokkaido island, northern Japan. Using 28,476 temperature data points from 433 boreholes sites and a method of Kriging with External Drift or trend (KED, SST distribution model from depths of 100 to 1500 m was produced. Regional LST was estimated from 13 scenes of Landsat 8 images. Resultant SST ranged from around 50 °C to 300 °C at a depth of 1500 m. Most of western and part of the eastern Hokkaido are characterized by high temperature gradients, while low temperatures were found in the central region. Higher temperatures in shallower crust imply the western region and part of the eastern region have high geothermal potential. Moreover, several LST zones considered to have high geothermal potential were identified upon clarification of the underground heat distribution according to 3D SST. LST in these zones showed the anomalies, 3 to 9 °C higher than the surrounding areas. These results demonstrate that our combination of TIR and 3D temperature modeling using well logging and geostatistics is an efficient and promising approach to geothermal resource exploration.

  13. A Low Temperature Analysis of the Boundary Driven Kawasaki Process

    Science.gov (United States)

    Maes, Christian; O'Kelly de Galway, Winny

    2013-12-01

    Low temperature analysis of nonequilibrium systems requires finding the states with the longest lifetime and that are most accessible from other states. We determine these dominant states for a one-dimensional diffusive lattice gas subject to exclusion and with nearest neighbor interaction. They do not correspond to lowest energy configurations even though the particle current tends to zero as the temperature reaches zero. That is because the dynamical activity that sets the effective time scale, also goes to zero with temperature. The result is a non-trivial asymptotic phase diagram, which crucially depends on the interaction coupling and the relative chemical potentials of the reservoirs.

  14. Low temperature inhibits root growth by reducing auxin accumulation via ARR1/12.

    Science.gov (United States)

    Zhu, Jiang; Zhang, Kun-Xiao; Wang, Wen-Shu; Gong, Wen; Liu, Wen-Cheng; Chen, Hong-Guo; Xu, Heng-Hao; Lu, Ying-Tang

    2015-04-01

    Plants exhibit reduced root growth when exposed to low temperature; however, how low temperature modulates root growth remains to be understood. Our study demonstrated that low temperature reduces both meristem size and cell number, repressing the division potential of meristematic cells by reducing auxin accumulation, possibly through the repressed expression of PIN1/3/7 and auxin biosynthesis-related genes, although the experiments with exogenous auxin application also suggest the involvement of other factor(s). In addition, we verified that ARABIDOPSIS RESPONSE REGULATOR 1 (ARR1) and ARR12 are involved in low temperature-mediated inhibition of root growth by showing that the roots of arr1-3 arr12-1 seedlings were less sensitive than wild-type roots to low temperature, in terms of changes in root length and meristem cell number. Furthermore, low temperature reduced the levels of PIN1/3 transcripts and the auxin level to a lesser extent in arr1-3 arr12-1 roots than in wild-type roots, suggesting that cytokinin signaling is involved in the low-temperature-mediated reduction of auxin accumulation. Taken together, our data suggest that low temperature inhibits root growth by reducing auxin accumulation via ARR1/12.

  15. New Mexico geothermal commercialization planning. Semi-annual progress report, January 1, 1979-June 30, 1979

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, P.; Scudella, G.; Fedor, D.

    1979-06-01

    The market potential for geothermal energy development in New Mexico is estimated. Barriers to market penetration and geothermal development initiatives were identified. Statutes and regulations affecting geothermal development are appended.

  16. Treatment of the early-stage glottic cancer using low-temperature radiofrequency coblation

    Directory of Open Access Journals (Sweden)

    Bing Liu

    2016-01-01

    Conclusions: Although the current probe design has limitations for the resection of certain tumors, low-temperature RF coblation appears to be a potentially effective method for the endoscopic resection of selected glottic cancers.

  17. Assessment of geothermal resources of the United States, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Muffler, L.J.P. (ed.)

    1979-01-01

    The geothermal resource assessment presented is a refinement and updating of USGS Circular 726. Nonproprietary information available in June 1978 is used to assess geothermal energy in the ground and, when possible, to evaluate the fraction that might be recovered at the surface. Five categories of geothermal energy are discussed: conduction-dominated regimes, igneous-related geothermal systems, high-temperature (> 150/sup 0/C) and intermediate-temperature (90 to 150/sup 0/C) hydrothermal convection systems, low-temperature (< 90/sup 0/C) geothermal waters, and geopressured-geothermal energy (both thermal energy and energy from dissolved methane). Assessment data are presented on three colored maps prepared in cooperation with the National Oceanic and Atmospheric Administration. Separate abstracts were prepared for papers on these five categories.

  18. Geothermal resources of California sedimentary basins

    Science.gov (United States)

    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 (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.

  19. Heat driven refrigeration cycle at low temperatures

    Institute of Scientific and Technical Information of China (English)

    HE Yijian; HONG Ronghua; CHEN Guangming

    2005-01-01

    Absorption refrigeration cycle can be driven by low-grade thermal energy, such as solar energy, geothermal energy and waste heat. It is beneficial to save energy and protect environment. However, the applications of traditional absorption refrigeration cycle are greatly restricted because they cannot achieve low refrigeration temperature. A new absorption refrigeration cycle is investigated in this paper, which is driven by low-grade energy and can get deep low refrigeration temperature. The mixture refrigerant R23+R134a and an absorbent DMF are used as its working fluid. The theoretical results indicate that the new cycle can achieve -62℃ refrigeration temperature when the generation temperature is only 160℃. This refrigeration temperature is much lower than that obtained by traditional absorption refrigeration cycle. Refrigeration temperature of -47.3℃ has been successfully achieved by experiment for this new cycle at the generation temperature of 157℃, which is the lowest temperature obtained by absorption refrigeration system reported in the literature up to now. The theoretical and experimental results prove that new cycle can achieve rather low refrigeration temperature.

  20. The science capability of the Low Temperature Microgravity Physics Facility

    Science.gov (United States)

    Larson, M.; Croonquist, A.; Dick, G. J.; Liu, Y.

    2002-01-01

    The Low Temperature Microgravity Physics Facility (LTMPF) is a multiple user and multiple-flight NASA facility that will provide a low temperature environment for about 4. 5 months on board the International Space Station (ISS).

  1. HTPro: Low-temperature Surface Hardening of Stainless Steel

    DEFF Research Database (Denmark)

    Christiansen, Thomas Lundin; Somers, Marcel A. J.

    2013-01-01

    Low-temperature surface hardening of stainless steel provides the required performance properties without affecting corrosion resistance.......Low-temperature surface hardening of stainless steel provides the required performance properties without affecting corrosion resistance....

  2. Investigation of geothermal resources in Korea (Geothermal Resources Maps)

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Jeong Ung; Lee, Seung Gu; Yum, Byoung Woo; Kim, Hyoung Chan [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

    1996-12-01

    The Korean Peninsula forms a part of the stable foreland of Far East Asia and is a part of Sino-Korean Craton, where, hence, is not associated with high potential geothermal resources. Nevertheless, there are several geothermal springs, of which water temperature ranges from 23 to 76 deg. C. This study was aimed to draw various geothermal base maps in the Korean Peninsula, such as thermal conductivity map, heat flow map, geothermal gradient map, depth contour map of 25 deg. C and various geochemical figures of geothermal waters. In this study, the thermal springs was surveyed for well inventory, the determination of thermal conductivities of rocks, and chemical analyses of geothermal waters. Hydrogen and oxygen isotope values ({delta}D and {delta}{sup 18}O) of geothermal waters were also calculated, which would be useful to evaluate the origin of water. Map of geothermal gradient distribution illustrates geothermally anomalous areas - such as Deoksan, Dogo, Onyang and Yusong areas in ChungNam district, Jungwon area in Chungbuk district, Pocheon area in Gyeonggi district, Gosung area in Gwangwon district, Deokgu, Baekam, and Pohang areas in Gyeongbuk district and Busan, Mageumsan and Bugok area in Gyeongnam district. Heat flow map also shows similar features to geothermal anomalies. Most of thermal waters form the Korean Peninsula are alkaline and belongs to Na-HCO{sub 3} type. Their contents are characterized of low total dissolved solids and high contents of fluoride and sodium, of which results are same as those of the researches which was conducted before. (author). 21 refs., tabs., figs.

  3. Washington: a guide to geothermal energy development

    Energy Technology Data Exchange (ETDEWEB)

    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)

  4. Modeling Low-temperature Geochemical Processes

    Science.gov (United States)

    Nordstrom, D. K.

    2003-12-01

    Geochemical modeling has become a popular and useful tool for a wide number of applications from research on the fundamental processes of water-rock interactions to regulatory requirements and decisions regarding permits for industrial and hazardous wastes. In low-temperature environments, generally thought of as those in the temperature range of 0-100 °C and close to atmospheric pressure (1 atm=1.01325 bar=101,325 Pa), complex hydrobiogeochemical reactions participate in an array of interconnected processes that affect us, and that, in turn, we affect. Understanding these complex processes often requires tools that are sufficiently sophisticated to portray multicomponent, multiphase chemical reactions yet transparent enough to reveal the main driving forces. Geochemical models are such tools. The major processes that they are required to model include mineral dissolution and precipitation; aqueous inorganic speciation and complexation; solute adsorption and desorption; ion exchange; oxidation-reduction; or redox; transformations; gas uptake or production; organic matter speciation and complexation; evaporation; dilution; water mixing; reaction during fluid flow; reaction involving biotic interactions; and photoreaction. These processes occur in rain, snow, fog, dry atmosphere, soils, bedrock weathering, streams, rivers, lakes, groundwaters, estuaries, brines, and diagenetic environments. Geochemical modeling attempts to understand the redistribution of elements and compounds, through anthropogenic and natural means, for a large range of scale from nanometer to global. "Aqueous geochemistry" and "environmental geochemistry" are often used interchangeably with "low-temperature geochemistry" to emphasize hydrologic or environmental objectives.Recognition of the strategy or philosophy behind the use of geochemical modeling is not often discussed or explicitly described. Plummer (1984, 1992) and Parkhurst and Plummer (1993) compare and contrast two approaches for

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

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Arlene [United States Department of Energy; Blackwell, David [Southern Methodist University; Chickering, Cathy [Southern Methodist University; Boyd, Toni [Oregon Institute of Technology; Horne, Roland [Stanford University; MacKenzie, Matthew [Uberity Technology Corporation; Moore, Joseph [University of Utah; Nickull, Duane [Uberity Technology Corporation; Richard, Stephen [Arizona Geological survey; Shevenell, Lisa A. [University of Nevada, Reno

    2013-10-01

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

  6. Monitoring of Acoustic Emissions Within Geothermal Areas in Iceland: A new Tool for Geothermal Exploration.

    Science.gov (United States)

    Brandsdóttir, B.; Gudmundsson, O.

    2007-12-01

    With increased emphasis on geothermal development new exploration methods are needed in order to improve general understanding of geothermal reservoirs, characterize their extent and assess the potential for sustainable power production. Monitoring of acoustic emissions within geothermal areas may provide a new tool to evaluate the spatial extent of geothermal fields and model rock-fluid interactions. Three-dimensional seismic data have been used to assess the spatial and temporal distribution of noise within several high-temperature geothermal fields in Iceland. Seismic noise in the 4-6 Hz range within the Svartsengi field can be attributed to steam hydraulics and pressure oscillations within the geothermal reservoirs. Seismic noise surveys compliment electrical resistivity soundings and TEM-surveys by providing information pertinent to the current geothermal activity and extent of steam fields within the uppermost crust of the geothermal reservoir. Information related to acoustic emissions can thus help define targets for future wells.

  7. Risk assessment of the Groningen geothermal potential : From seismic to reservoir uncertainty using a discrete parameter analysis

    NARCIS (Netherlands)

    Daniilidis, Alexandros; Doddema, Leon; Herber, Rien

    2016-01-01

    Geothermal exploitation is subject to several uncertainties, even in settings with high data availability, adding to project risk. Uncertainty can stem from the reservoir's initial state, as well as from the geological and operational parameters. The interplay between these aspects entails

  8. Risk assessment of the Groningen geothermal potential : From seismic to reservoir uncertainty using a discrete parameter analysis

    NARCIS (Netherlands)

    Daniilidis, Alexandros; Doddema, Leon; Herber, Rien

    2016-01-01

    Geothermal exploitation is subject to several uncertainties, even in settings with high data availability, adding to project risk. Uncertainty can stem from the reservoir's initial state, as well as from the geological and operational parameters. The interplay between these aspects entails irreducib

  9. Risk assessment of the Groningen geothermal potential : From seismic to reservoir uncertainty using a discrete parameter analysis

    NARCIS (Netherlands)

    Daniilidis, Alexandros; Doddema, Leon; Herber, Rien

    2016-01-01

    Geothermal exploitation is subject to several uncertainties, even in settings with high data availability, adding to project risk. Uncertainty can stem from the reservoir's initial state, as well as from the geological and operational parameters. The interplay between these aspects entails irreducib

  10. 7{sup th} international geothermal conference

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Jochen; Brian, Marcus; Dittmann, Elena (eds.)

    2011-05-10

    Within the 7th International Geothermal Conference from 10th to 12th May, 2011 in Freiburg (Federal Republic of Germany) the following lectures and posters were presented: (1) Global Geothermal Energy - Status and Challenges (L. Rybach); (2) The development of deep geothermal energy in Switzerland - Facts and perspectives (R. Wyss); (3) The importance of geothermal energy in the energy mix of the future (W. Muench); (4) Living with induced seismicity: Lessons from Basel and a roadmap ahead (S. Wiemer); (5) The seismic event in Landau, August 2009: Expert Group and research projects as follow-up (C. Boennemann); (6) Microseismicity (S. Baisch); (7) EU Research project GEISER for investigation of induced seismicity (T. Kohl); (8) Seismic hazard related to geothermal projects - expert view (H. Rueter); (9) Geological investigation (U. Schanz); (10) Drill design (W. Mueller-Ruhe); (11) Reducing costs for pumping geothermal water (H. Schroeder); (12) Optimisation of cycle processes - Best exergy point for ORC (S. Schuller); (13) High-potential working fluids for next-generation binary ORC (A.L. Laursen); (14) Geothermal energy - An essential part of future electricity production (C. Lohse); (15) Revision of the renewable Enrgy Sources Act (EEG) in 2011 (C. Viertl); (16) Amendment to the Renewable Energy Sources Act - Further development for the deep geothermal industry (E, Knapek); (17) Geothermal energy as an opportunity for energy supplies (J. Uhde); (18) Project financing - Democracy as a success factor (F. Fritsch); (19) Fund financing of geothermal projects (C. Deneke); (20) Geothermal Energy - requirements and perspectives from a utility point of view (M. Voss); (21) Hurdles for financing geothermal projects in Germany (M. Wiendieck); (22) Licenses for exploration of geothermal energy in Baden-Wuerttemberg (A. Brasse); (23) New reflections on the exploration strategy concerning the malm of the melasse basin (K. Dorsch); (24) Situation of the mining law in

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

    Energy Technology Data Exchange (ETDEWEB)

    Arney, B.H.; Goff, F.

    1982-05-01

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

  12. Geothermal hot water potential at Parangwedang, Parangtritis, Bantul, Yogyakarta as main support of Geotourism

    Directory of Open Access Journals (Sweden)

    Suhascaryo KRT. Nur

    2017-01-01

    Full Text Available The paper aims to determine the condition of Parangwedang as hot spring source in Parangtritis, Bantul, Yogyakarta and provide a guidance to develop Parangwedang as one of tourism destinations by controlling geological factor. The study is limited to examining the physical condition in the form of color, turbidity, odor, temperature and chemical condition (pH, compositions of calcium (Ca, sodium (Na, silica (SiO2, magnesium (Mg, bicarbonate (HCO3, sulfate (SO4 and chloride (Cl and water source debits of Parangwedang hot springs as part of geohydrology research. The methodology used in the paper is divided into three steps. Firstly, the methodology was based on orientation and survey location. Then, it examined mapping the hot water temperature distribution. Lastly, it was implementing laboratory analysis of rocks and water. As a result, the paper portrays that there are potential water of hot of spring which meets the standards as clean water and the heat capacity can be utilized to support as geological tourism at Parangwedang, Bantul, Yogyakarta, Indonesia.

  13. Magnetic structure at low temperatures in FeGe2

    Science.gov (United States)

    Babu, P. D.; Mishra, P. K.; Dube, V.; Mishra, R.; Sastry, P. U.; Ravikumar, G.

    2014-04-01

    Magnetic phase of FeGe2 intermetallic is studied using low-temperature neutron diffraction and DC magnetization. Zero-magnetic-field neutron scattering data shows the presence of an antiferromagnetic phase in the low temperature range. We find the evidence of the presence of a ferromagnetic order overriding on the predominantly antiferromagnetic phase at low temperatures.

  14. Low temperature surface conductivity of hydrogenated diamond

    Energy Technology Data Exchange (ETDEWEB)

    Sauerer, C.; Ertl, F.; Nebel, C.E.; Stutzmann, M. [Technische Univ. Muenchen, Garching (Germany). Walter-Schottky-Inst. fuer Physikalische Grundlagen der Halbleiterelektronik; Bergonzo, P. [LIST(CEA-Recherche Technology)/DIMIR/SIAR/Saclay, Gif-sur-Yvette (France); Williams, O.A.; Jackman, R.A. [University Coll., London (United Kingdom). Dept. of Electrical and Electronic Engineering

    2001-07-23

    Conductivity and Hall experiments are performed on hydrogenated poly-CVD, atomically flat homoepitaxially grown Ib and natural type IIa diamond layers in the regime 0.34 to 400 K. For all experiments hole transport is detected with sheet resistivities at room temperature in the range 10{sup 4} to 10{sup 5} {omega}/{radical}. We introduce a transport model where a disorder induced tail of localized states traps holes at very low temperatures (T < 70 K). The characteristic energy of the tail is in the range of 6 meV. Towards higher temperatures (T > 70 K) the hole density is approximately constant and the hole mobility {mu} is increasing two orders of magnitude. In the regime 70 K < T < 200 K, {mu} is exponentially activated with 22 meV, above it follows a {proportional_to}T{sup 3/2} law. The activation energy of the hole density at T < 70 K is governed by the energy gap between holes trapped in the tail and the mobility edge which they can propagate. In the temperature regime T < 25 K an increasing hole mobility is detected which is attributed to transport in delocalized states at the surface. (orig.)

  15. a Low Temperature Regenerator Test Facility

    Science.gov (United States)

    Kashani, A.; Helvensteijn, B. P. M.; Feller, J. R.; Salerno, L. J.; Kittel, P.

    2008-03-01

    Testing regenerators presents an interesting challenge. When incorporated into a cryocooler, a regenerator is intimately coupled to the other components: expander, heat exchangers, and compressor. It is difficult to isolate the performance of any single component. We have developed a low temperature test facility that will allow us to separate the performance of the regenerator from the rest of the cryocooler. The purpose of the facility is the characterization of test regenerators using novel materials and/or geometries in temperature ranges down to 15 K. It consists of the following elements: The test column has two regenerators stacked in series. The coldest stage regenerator is the device under test. The warmer stage regenerator contains a stack of stainless steel screen, a well-characterized material. A commercial cryocooler is used to fix the temperatures at both ends of the test regenerator, cooling both heat exchangers flanging the regenerator stack. Heaters allow varying the temperatures and allow measurement of the remaining cooling power, and thus, regenerator effectiveness. A linear compressor delivers an oscillating pressure to the regenerator assembly. An inertance tube and reservoir provide the proper phase difference between mass flow and pressure. This phase shift, along with the imposed temperature differential, simulates the conditions of the test regenerator when used in an actual pulse tube cryocooler. This paper presents development details of the regenerator test facility, and test results on a second stage, stainless steel screen test regenerator.

  16. The potential for biocontrol in stored products in general, with specific attention to application of parasitoids against Sitophilus granarius in grains stores at low temperatures

    DEFF Research Database (Denmark)

    Hansen, Lise Stengård

    : This presentation will give an overview of the current state of biocontrol in stored products. An EU-funded COST Action Working Group, active during 2000-2006. evaluated the possibilities in different sectors: grain stores, mills and bakeries, pasta factories, stored nuts and dried fruit, etc. Three situations were...... identified with the greatest potential for widespread application: (1) empty room treatment against mites, beetles and moths, (2) treatment of bulk commodities against Sitophilus spp. and mites, and (3) application of egg-parasitoids against moths in packaged products. As an example, results of research...

  17. GEOTHERMICS GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>20111059 Gao Jinghong(Engineering Group Co.Ltd.of the Second Institute of China Railway,Chengdu 610031,China);Tong Tiegang A Magnetotelluric Study of Geothermal Resources in Kaifeng Depression,Henan Province(Geophysical and Geochemical Exploration,ISSN1000-8918,CN11-1906/P,34(4),2010,p.440-443,6 illus.,12 refs.)Key words:geothermal resources,telluric electromagnetic sounding,Henan Province Kaifeng Depression,located in the southeast corner of the Jiyuan-Kaifeng Depression,is enriched with deep-seated groundwater sources.The rich geothermal water rock(thermal reservoir)commonly has lower resistivity than the in-situ rock,and the reduction degree of its resistivity is related to the extent of water content,water temperature and mineralization.Based on geo-electrical anomaly,the authors inferred the distribution of the thermal reservoirs.A study of the magnetotelluric sounding method(MT)shows that the resistivity values of the basement are lowest in most surveying points north of F1 fault,implying the existence of the relationship with the geothermal water in the strata.According to the distribution of geo-electrical anomalies in the survey area,the authors locate the relatively enriched area of geothermal water in the basement of this area,thus providing an important basis

  18. Feasibility of geothermal heat use in the San Bernardino Municipal Wastewater Treatment Plant. Final report, September 1980-June 1981

    Energy Technology Data Exchange (ETDEWEB)

    Racine, W.C.; Larson, T.C.; Stewart, C.A.; Wessel, H.B.

    1981-06-01

    A system was developed for utilizing nearby low temperature geothermal energy to heat two high-rate primary anaerobic digesters at the San Bernardino Wastewater Treatment Plant. The geothermal fluid would replace the methane currently burned to fuel the digesters. A summary of the work accomplished on the feasibility study is presented. The design and operation of the facility are examined and potentially viable applications selected for additional study. Results of these investigations and system descriptions and equipment specifications for utilizing geothermal energy in the selected processes are presented. The economic analyses conducted on the six engineering design cases are discussed. The environmental setting of the project and an analysis of the environmental impacts that will result from construction and operation of the geothermal heating system are discussed. A Resource Development Plan describes the steps that the San Bernardino Municipal Water Department could follow in order to utilize the resource. A preliminary well program and rough cost estimates for the production and injection wells also are included. The Water Department is provided with a program and schedule for implementing a geothermal system to serve the wastewater treatment plant. Regulatory, financial, and legal issues that will impact the project are presented in the Appendix. An outline of a Public Awareness Program is included.

  19. Feasibility of geothermal heat use in the San Bernardino Municipal Wastewater Treatment Plant. Final report, September 1980-June 1981

    Energy Technology Data Exchange (ETDEWEB)

    Racine, W.C.; Larson, T.C.; Stewart, C.A.; Wessel, H.B.

    1981-06-01

    A system was developed for utilizing nearby low temperature geothermal energy to heat two high-rate primary anaerobic digesters at the San Bernardino Wastewater Treatment Plant. The geothermal fluid would replace the methane currently burned to fuel the digesters. A summary of the work accomplished on the feasibility study is presented. The design and operation of the facility are examined and potentially viable applications selected for additional study. Results of these investigations and system descriptions and equipment specifications for utilizing geothermal energy in the selected processes are presented. The economic analyses conducted on the six engineering design cases are discussed. The environmental setting of the project and an analysis of the environmental impacts that will result from construction and operation of the geothermal heating system are discussed. A Resource Development Plan describes the steps that the San Bernardino Municipal Water Department could follow in order to utilize the resource. A preliminary well program and rough cost estimates for the production and injection wells also are included. The Water Department is provided with a program and schedule for implementing a geothermal system to serve the wastewater treatment plant. Regulatory, financial, and legal issues that will impact the project are presented in the Appendix. An outline of a Public Awareness Program is included.

  20. Study deep geothermal energy; Studie dypgeotermisk energi

    Energy Technology Data Exchange (ETDEWEB)

    Havellen, Vidar; Eri, Lars Sigurd; Andersen, Andreas; Tuttle, Kevin J.; Ruden, Dorottya Bartucz; Ruden, Fridtjof; Rigler, Balazs; Pascal, Christophe; Larsen, Bjoern Tore

    2012-07-01

    The study aims to analyze the potential energy with current technology, challenges, issues and opportunities for deep geothermal energy using quantitative analysis. It should especially be made to identify and investigate critical connections between geothermal potential, the size of the heating requirements and technical solutions. Examples of critical relationships may be acceptable cost of technology in relation to heating, local geothermal gradient / drilling depth / temperature levels and profitability. (eb)

  1. Hot dry rock geothermal energy

    Science.gov (United States)

    Heiken, G.; Murphy, H.; Nunz, G.; Potter, R.

    1981-08-01

    Man-made geothermal systems are discussed which make it possible to extract heat from hot rocks in areas where natural fluids are insufficient for the development of hydrothermal energy. The location and magnitude of high- and low-temperature geothermal resources in the USA for such hot dry rock (HDR) systems are examined. An HDR concept is described in which water is injected into one of two nearly parallel wells connected at depth by man-made fractures; the injected water circulates through the fracture system, where it is heated by conduction from the hot rock, and hot fluid, which can be used for heating or for electric power generation, rises through the second well. Some heat-extraction experiments using the described concept are reviewed which are being conducted in a complex volcanic field in New Mexico. The economics of HDR energy is evaluated.

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

    Energy Technology Data Exchange (ETDEWEB)

    Elizabeth Battocletti

    2003-05-01

    --the geothermal entrepreneur, small company, or project developer--step-by-step through the process needed to structure a business and financing plan for a small geothermal project; and Help you develop a financing plan that can be adapted and taken to potential financing sources. The Workbook will not: Substitute for financial advice; Overcome the high exploration, development, and financing costs associated with smaller geothermal projects; Remedy the lack of financing for the exploration stage of a geothermal project; or Solve financing problems that are not related to the economic soundness of your project or are caused by things outside of your control.

  3. [On Atomic Nuclear Fusion Processes at Low-Temperatures. An Enhancement of the Probability of Transition through a Potential Barrier Due to the So-Called Barrier Anti-Zeno Effect].

    Science.gov (United States)

    Namiot, V A

    2016-01-01

    It is known that in quantum mechanics the act of observing the experiment can affect the experimental findings in some cases. In particular, it happens under the so-called Zeno effect. In this work it is shown that in contrast to the "standard" Zeno-effect where the act of observing a process reduces the probability of its reality, an inverse situation when a particle transmits through a potential barrier (a so-called barrier anti-Zeno effect) can be observed, the observation of the particle essentially increases the probability of its transmission through the barrier. The possibility of using the barrier anti-Zeno effect is discussed to explain paradoxical results of experiments on "cold nuclear fusion" observed in various systems including biological ones. (According to the observers who performed the observations, the energy generation, which could not be explained by any chemical processes, as well as the change in the isotope and even element composition of the studied object may occur in these systems.

  4. Vertical distribution of potentially toxic elements in sediments impacted by intertidal geothermal hot springs (Bahia Concepcion, Gulf of California)

    Science.gov (United States)

    Leal-Acosta, M. L.; Shumilin, E.

    2016-12-01

    The intertidal geothermal hot springs (GHS) in Bahia Concepcion, Gulf of California are the source of potentially toxic elements to the adjacent marine environment surrounded by mangroves trees. The anoxic sediments enriched in organic carbon accumulate As, Hg and other heavy metals that can be bioavailable for the biota. To know the vertical distribution of these elements the geochemistry of a short sediment core was carried out. It was collected in June, 2010 in the mangrove area near to GHS (1 m) during a low tide, pushing manually a polypropylene tube into the sediments. The extracted sediment core was cut with plastic knife on 1 cm thick sub-samples, stored in plastic bags and transported on ice to the laboratory. The major and trace elements contents were determinate by ICP-MS after total digestion with stronger acids (HClO4-HNO3-HCl-HF). Certificate reference materials were used for the quality control of the method obtaining good recoveries for most of the elements (80-105%). The sediment core had high maximum contents of CaCO3 (70%) and total organic carbon (12%). The concentration of Hg along the core ranges from 650 to 74300 mg kg-1 and had more than three orders of magnitude above the reference values of 40 mg kg-1 for the Upper Continental Crust (UCC)1. In contrast, As ranges from 12 to 258 mg kg-1 resulting in more than one order of magnitude respect to UCC1 (1.7 mg kg-1). Similar pattern result for Mn, Cu, Pb, and Zn with the maximum values of 3200 mg kg-1, 42 mg kg-1, 12.4 mg kg-1, 71 mg kg-1 respectively that coincide with the maximum for As at the same core depth (4 cm). The Ca, Li, Co, Sb, U, and Mg also show high contents in comparison with the UCC1reference values. The maximum contents of Mo and Cd coincide with maximum concentration of sulfur (2%) at 6 to 8 cm. The enrichment factor calculated using Al as normalizing element showed Cd (7-280), As (26-329) and Hg (23-1196) as highly enriched mainly in the first centimeters of the sediment core

  5. Sustainable renewable energy seawater desalination using combined-cycle solar and geothermal heat sources

    KAUST Repository

    Missimer, Thomas M.

    2013-01-01

    Key goals in the improvement of desalination technology are to reduce overall energy consumption, make the process "greener," and reduce the cost of the delivered water. Adsorption desalination (AD) is a promising new technology that has great potential to reduce the need for conventional power, to use solely renewable energy sources, and to reduce the overall cost of water treatment. This technology can desalt seawater or water of even higher salinity using waste heat, solar heat, or geothermal heat. An AD system can operate effectively at temperatures ranging from 55 to 80 °C with perhaps an optimal temperature of 80 °C. The generally low temperature requirement for the feedwater allows the system to operate quite efficiently using an alternative energy source, such as solar power. Solar power, particularly in warm dry regions, can generate a consistent water temperature of about 90 °C. Although this temperature is more than adequate to run the system, solar energy collection only can occur during daylight hours, thereby necessitating the use of heat storage during nighttime or very cloudy days. With increasing capacity, the need for extensive thermal storage may be problematic and could add substantial cost to the development of an AD system. However, in many parts of the world, there are subsurface geothermal energy sources that have not been extensively used. Combining a low to moderate geothermal energy recovery system to an AD system would provide a solution to the thermal storage issue. However, geothermal energy development from particularly Hot Dry Rock is limited by the magnitude of the heat flow required for the process and the thermal conductivity of the rock material forming the heat reservoir. Combining solar and geothermal energy using an alternating 12-h cycle would reduce the probability of depleting the heat source within the geothermal reservoir and provide the most effective use of renewable energy. © 2013 Desalination Publications.

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

    Science.gov (United States)

    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

  7. GEOTHERMICS GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>20111836 Gao Jian(Sichuan Institute of Geological Survey for Nuclear Industry,Chengdu 610061,China);Shi Yuzhen Feasibility Study of Exploitation of Geothermal Resource in the Lugu Lake Region,Yanyuan,Sichuan Province(Acta Geologica Sichuan,ISSN1006-0995,CN51-1273/P,30(3),2010,p.291-294,1 illus.,1 table,1 ref.,with English abstract)Key words:geothermal water,Sichuan Province20111837 He Jianhua(Geological Brigade 102,Bureau of Geolog

  8. GEOTHERMICS GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    <正>20140332 Jiang Lin(School of Earth and Space Sciences,Peking University,Beijing100871,China);Ji Jianqing Geologic Analysis on the Prospects of the Enhanced Geothermal System(EGS)in the Bohaiwan Basin(Geology and Prospecting,ISSN0495-5331,CN11-2043/P,49(1),2013,p.167-178,5illus.,4tables,41refs.)Key words:geothermal systems,Bohaiwan Basin Great amounts of thermal energy is stored ubiquitously in rocks with high tempera-

  9. Room and low temperature synthesis of carbon nanofibres

    CERN Document Server

    Boskovic, B O

    2002-01-01

    Carbon nanotubes and nanofibres have attracted attention in recent years as new materials with a number of very promising potential applications. Carbon nanotubes are potential candidates for field emitters in flat panel displays. Carbon nanofibres could also be used as a hydrogen storage material and as a filling material in polymer composites. Carbon nanotubes are already used as tips in scanning probe microscopy due to their remarkable mechanical and electrical properties, and could be soon used as nanotweezers. Use of carbon nanotubes in nanoelectronics will open further miniaturisation prospects. Temperatures ranging from 450 to 1000 deg C have been a required for catalytic growth of carbon nanotubes and nanofibres. Researchers have been trying to reduce the growth temperatures for decades. Low temperature growth conditions will allow the growth of carbon nanotubes on different substrates, such glass (below 650 deg C) and as plastics (below 150 deg C) over relatively large areas, which is especially suit...

  10. Anodes for Solid Oxide Fuel Cells Operating at Low Temperatures

    DEFF Research Database (Denmark)

    Abdul Jabbar, Mohammed Hussain

    An important issue that has limited the potential of Solid Oxide Fuel Cells (SOFCs) for portable applications is its high operating temperatures (800-1000 ºC). Lowering the operating temperature of SOFCs to 400-600 ºC enable a wider material selection, reduced degradation and increased lifetime....... On the other hand, low-temperature operation poses serious challenges to the electrode performance. Effective catalysts, redox stable electrodes with improved microstructures are the prime requisite for the development of efficient SOFC anodes. The performance of Nb-doped SrT iO3 (STN) ceramic anodes...... at 400ºC. The potential of using WO3 ceramic as an alternative anode materials has been explored. The relatively high electrode polarization resistance obtained, 11 Ohm cm2 at 600 ºC, proved the inadequate catalytic activity of this system for hydrogen oxidation. At the end of this thesis...

  11. Potential use of geothermal resources in the Snake River Basin: an environmental overview. Volume II. Annotated bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, S.G.; Russell, B.F.; Sullivan, J.F. (eds.)

    1979-09-01

    This volume is a partially annotated bibliography of reference materials pertaining to the seven KGRA's. The bibliography is divided into sections by program element as follows: terrestrial ecology, aquatic ecology, heritage resources, socioeconomics and demography, geology, geothermal, soils, hydrology and water quality, seismicity, and subsidence. Cross-referencing is available for those references which are applicable to specific KGRA's. (MHR)

  12. Geothermal resources and energy complex use in Russia

    Science.gov (United States)

    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

  13. Geothermal energy for American Samoa

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. A survey of endangered waterbirds on Maui and Oahu and assessment of potential impacts to waterbirds from the proposed Hawaii Geothermal Project transmission corridor. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Evans, K.; Woodside, D.; Bruegmann, M. [Fish and Wildlife Service, Honolulu, HI (United States). Pacific Islands Office

    1994-08-01

    A survey of endangered waterbirds on Maui and Oahu was conducted during August and September 1993 to identify potential waterbird habitats within the general area of the proposed Hawaii Geothermal Project transmission corridor and to assess the potential impacts to endangered waterbird of installing and operating a high voltage transmission line from the Island of Hawaii to the islands of Oahu and Maui. Annual waterbird survey information and other literature containing information on specific wetland sites were summarized. Literature describing impacts of overhead transmission lines on birds was used to evaluate potential impacts of the proposed project on endangered waterbirds, resident wading birds, and migratory shorebirds and waterfowl. On Oahu, five wetland habitats supporting endangered Hawaiian waterbirds were identified within 2.5 miles of the proposed transmission line corridor. On Maui, three wetland habitats supporting endangered Hawaiian waterbirds were identified within the general area of the proposed transmission line corridor. Several of the wetlands identified on Oahu and Maui also supported resident wading birds and migratory shorebirds and waterfowl. Endangered waterbirds, resident wading birds, and migratory birds may collide with the proposed transmission lines wires. The frequency and numbers of bird collisions is expected to be greater on Oahu than on Maui because more wetland habitat exists and greater numbers of birds occur in the project area on Oahu. In addition, the endangered Hawaiian goose and the endangered Hawaiian petrel may be impacted by the proposed segment of the Hawaii Geothermal Project transmission line on Maui.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  16. Economic assessment of geothermal direct heat technology: A review of five DOE demonstration projects

    Energy Technology Data Exchange (ETDEWEB)

    Hederman, William F. Jr.; Cohen, Laura A.

    1981-06-01

    In this report the cost of using low temperature geothermal energy resources for direct heating applications is compared to the costs associated with conventional heating fuels. The projects compared all involved replacing conventional fuels (e.g., natural gas and fuel oils) with geothermal energy in existing heating systems. The cost of using geothermal energy in existing systems was also compared with the cost of new coal-fired equipment.

  17. Thermoeconomic Analysis of Hybrid Power Plant Concepts for Geothermal Combined Heat and Power Generation

    OpenAIRE

    Florian Heberle; Dieter Brüggemann

    2014-01-01

    We present a thermo-economic analysis for a low-temperature Organic Rankine Cycle (ORC) in a combined heat and power generation (CHP) case. For the hybrid power plant, thermal energy input is provided by a geothermal resource coupled with the exhaust gases of a biogas engine. A comparison to alternative geothermal CHP concepts is performed by considering variable parameters like ORC working fluid, supply temperature of the heating network or geothermal water temperature. Second law efficiency...

  18. Composite Materials for Low-Temperature Applications

    Science.gov (United States)

    2008-01-01

    Composite materials with improved thermal conductivity and good mechanical strength properties should allow for the design and construction of more thermally efficient components (such as pipes and valves) for use in fluid-processing systems. These materials should have wide application in any number of systems, including ground support equipment (GSE), lunar systems, and flight hardware that need reduced heat transfer. Researchers from the Polymer Science and Technology Laboratory and the Cryogenics Laboratory at Kennedy Space Center were able to develop a new series of composite materials that can meet NASA's needs for lightweight materials/composites for use in fluid systems and also expand the plastic-additive markets. With respect to thermal conductivity and physical properties, these materials are excellent alternatives to prior composite materials and can be used in the aerospace, automotive, military, electronics, food-packaging, and textile markets. One specific application of the polymeric composition is for use in tanks, pipes, valves, structural supports, and components for hot or cold fluid-processing systems where heat flow through materials is a problem to be avoided. These materials can also substitute for metals in cryogenic and other low-temperature applications. These organic/inorganic polymeric composite materials were invented with significant reduction in heat transfer properties. Decreases of 20 to 50 percent in thermal conductivity versus that of the unmodified polymer matrix were measured. These novel composite materials also maintain mechanical properties of the unmodified polymer matrix. These composite materials consist of an inorganic additive combined with a thermoplastic polymer material. The intrinsic, low thermal conductivity of the additive is imparted into the thermoplastic, resulting in a significant reduction in heat transfer over that of the base polymer itself, yet maintaining most of the polymer's original properties. Normal

  19. Reno Industrial Park geothermal district heating system

    Energy Technology Data Exchange (ETDEWEB)

    Lienau, P.J.

    1997-04-01

    Ten miles south of Reno, on U.S. 395 near the junction of the road to historic Virginia City, is Steamboat Hot Springs, a popular stop for travelers since the mid-1800s. Legend has it that Mark Twain named the geothermal area because it looked and sounded like a chugging Mississippi River paddle-wheeler. It is said when he first saw the steam rising from the ground he exclaimed, {open_quotes}Behold! A Steamboat in the desert.{close_quotes} Over the years, the area has been used for its relaxing and curative qualities by Indians, settlers, and geothermal experts. Since the mid-1980s five geothermal power plants have been built at Steamboat Springs and in December 1996 it was announced that the proposed largest geothermal district heating system in the U.S. would supply an industrial park in the area. The active geothermal area is located within the north-south trending graben like trough between the Carson and Virginia Ranges at the southern end of Truckee Meadows. Hot springs and other geothermal features occur over an area of about one square mile. The mid-basin location is controlled by faulting more or less parallel to the major mountain-front faults. It is believed that the heat source for the system is a cooling magmatic body at depth. The Steamboat geothermal area consists of a deep, high-temperature (215{degrees}C to 240{degrees} C) geothermal system, a shallower, moderate-temperature (160{degrees}C to 18{degrees} C) system, and a number of shallow low-temperature (30{degrees}C to 80{degrees}C) subsystems. The higher temperature systems are used for electric-power generation. It is proposed that the exit fluids from the electric power plants be used for the geothermal district heating system.

  20. Doubling Geothermal Generation Capacity by 2020. A Strategic Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Wall, Anna [National Renewable Energy Lab. (NREL), Golden, CO (United States); Young, Katherine [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-01-01

    This report identifies the potential of U.S. geothermal resource and the current market to add an additional 3 GW of geothermal by 2020, in order to meet the goal set forth in the Climate Action Plan.

  1. Calorimetric low temperature detectors for heavy ion physics

    Energy Technology Data Exchange (ETDEWEB)

    Egelhof, P.; Kraft-Bermuth, S. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)]|[Mainz Univ. (Germany). Inst. fuer Physik

    2005-05-01

    Calorimetric low temperature detectors have the potential to become powerful tools for applications in many fields of heavy ion physics. A brief overview of heavy ion physics at present and at the next generation heavy ion facilities is given with a special emphasis on the conditions for heavy ion detection and the potential advantage of cryogenic detectors for applications in heavy ion physics. Two types of calorimetric low temperature detectors for the detection of energetic heavy ions have been developed and their response to the impact of heavy ions was investigated systematically for a wide range of energies (E=0.1-360 MeV/amu) and ion species ({sup 4}He.. {sup 238}U). Excellent results with respect to energy resolution, {delta}E/E ranging from 1 to 5 x 10{sup -3} even for the heaviest ions, and other basic detector properties such as energy linearity with no indication of a pulse height defect, energy threshold, detection efficiency and radiation hardness have been obtained, representing a considerable improvement as compared to conventional heavy ion detectors based on ionization. With the achieved performance, calorimetric low temperature detectors bear a large potential for applications in various fields of basic and applied heavy ion research. A brief overview of a few prominent examples, such as high resolution nuclear spectroscopy, high resolution nuclear mass determination, which may be favourably used for identification of superheavy elements or in direct reaction experiments with radioactive beams, as well as background discrimination in accelerator mass spectrometry, is given, and first results are presented. For instance, the use of cryogenic detectors allowed to improve the sensitivity in trace analysis of {sup 236}U by one order of magnitude and to determine the up to date smallest isotope ratio of {sup 236}U/{sup 238}U = 6.1 x 10{sup -12} in a sample of natural uranium. Besides the detection of heavy ions, the concept of cryogenic detectors also

  2. GEOTHERMICS GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    20151090 Bian Huiying(School of Environmental Sciences and Engineering,Chang’an University,Xi’an 10054,China);Wang Shuangming Hydrodynamic Conditions of Geothermal Water in Gushi Depression of Guanzhong Basin(Coal Geology&Exploration;,ISSN1001-1986,CN61-1155/P,42(3),2014,p.50-54,60,9illus.,11refs.,

  3. GEOTHERMICS GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    <正>20140958 Mei Huicheng(No.915GeologicalBrigade,Jiangxi Bureau of Geology and Mineral Resources,Nanchang 330002,China);Li Zhongshe Geological Features and Causes of the Huihuang Geotherm in Xiushui,Jiangxi Province(Journal of Geological Hazards and

  4. Geothermal Energy

    Science.gov (United States)

    1975-11-15

    kaolinization . Deposition of silica can easily be observed in the Geysers field, where fractures of one-inch width, completely filled and sealed...by silica and calcite, are common features. Kaolinization , associated with other more complicated hydrothermal rock alteration, is also...techniques. Surface corrosion may be extremely severe in geothermal fluids containing free hydrochloric, sulphuric or hydrofluoric acid

  5. GEOTHERMICS GEOLOGY

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>20070403 Deng Xiaoying (Zhengzhou Geo-Engineering Exploration Institute, Zhengzhou 450053, China); Yang Guoping Features and Origin of Geothermal Fluid in the New District of Hebi, Henan Provionce (Hydrogeology & Engineering Geology, ISSN1000-3665, CN11-2202/P, 32(2), 2005, p.111-114, 4 illus., 1 table, 7 refs.) Key words: thermal waters, Henan Province

  6. Geothermal development plan: Maricopa County

    Energy Technology Data Exchange (ETDEWEB)

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

    1982-08-01

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

  7. Monitoring the hydrologic system for potential effects of geothermal and ground-water development in the Long Valley caldera, Mono County, California, U.S.A.

    Science.gov (United States)

    Farrar, C.D.; Lyster, D. L.

    1990-01-01

    In the early 1980's, renewed interest in the geothermal potential of the Long Valley caldera, California, highlighted the need to balance the benefits of energy development with the established recreational activities of the area. The Long Valley Hydrologic Advisory Committee, formed in 1987, instituted a monitoring program to collect data during the early stages of resource utilization to evaluate potential effects on the hydrologic system. Early data show declines in streamflow, spring flow, and ground-water levels caused by 6 years of below-average precipitation. Springs in the Hot Creek State Fish Hatchery area discharge water that is a mixture of nonthermal and hydrothermal components. Possible sources of nonthermal water have been identified by comparing deuterium concentrations in streams and springs. The equivalent amount of undiluted thermal water discharged from the springs was calculated on the basis of boron and chloride concentrations. Quantifying the thermal and nonthermal fractions of the total flow may allow researchers to assess changes in flow volume or temperature of the springs caused by groundwater or geothermal development.

  8. Geothermal areas as analogues to chemical processes in the near-field and altered zone of the potential Yucca Mountain, Nevada repository

    Energy Technology Data Exchange (ETDEWEB)

    Bruton, C.J.; Glassley, W.E.; Meike, A.

    1995-02-01

    The need to bound system performance of the potential Yucca Mountain repository for thousands of years after emplacement of high-level nuclear waste requires the use of computer codes. The use of such codes to produce reliable bounds over such long time periods must be tested using long-lived natural and historical systems as analogues. The geothermal systems of the Taupo Volcanic Zone (TVZ) in New Zealand were selected as the site most amenable to study. The rocks of the TVZ are silicic volcanics that are similar in composition to Yucca Mountain. The area has been subjected to temperatures of 25 to 300 C which have produced a variety of secondary minerals similar to those anticipated at Yucca Mountain. The availability of rocks, fluids and fabricated materials for sampling is excellent because of widespread exploitation of the systems for geothermal power. Current work has focused on testing the ability of the EQ3/6 code and thermodynamic data base to describe mineral-fluid relations at elevated temperatures. Welfare starting long-term dissolution/corrosion tests of rocks, minerals and manufactured materials in natural thermal features in order to compare laboratory rates with field-derived rates. Available field data on rates of silica precipitation from heated fluids have been analyzed and compared to laboratory rates. New sets of precipitation experiments are being planned. The microbially influenced degradation of concrete in the Broadlands-Ohaaki geothermal field is being characterized. The authors will continue to work on these projects in FY 1996 and expand to include the study of naturally occurring uranium and thorium series radionuclides, as a prelude to studying radionuclide migration in heated silicic volcanic rocks. 32 refs.

  9. Geothermal areas as analogues to chemical processes in the near-field and altered zone of the potential Yucca Mountain, Nevada repository

    Energy Technology Data Exchange (ETDEWEB)

    Bruton, C.J.; Glassley, W.E.; Meike, A.

    1995-02-01

    The need to bound system performance of the potential Yucca Mountain repository for thousands of years after emplacement of high-level nuclear waste requires the use of computer codes. The use of such codes to produce reliable bounds over such long time periods must be tested using long-lived natural and historical systems as analogues. The geothermal systems of the Taupo Volcanic Zone (TVZ) in New Zealand were selected as the site most amenable to study. The rocks of the TVZ are silicic volcanics that are similar in composition to Yucca Mountain. The area has been subjected to temperatures of 25 to 300 C which have produced a variety of secondary minerals similar to those anticipated at Yucca Mountain. The availability of rocks, fluids and fabricated materials for sampling is excellent because of widespread exploitation of the systems for geothermal power. Current work has focused on testing the ability of the EQ3/6 code and thermodynamic data base to describe mineral-fluid relations at elevated temperatures. Welfare starting long-term dissolution/corrosion tests of rocks, minerals and manufactured materials in natural thermal features in order to compare laboratory rates with field-derived rates. Available field data on rates of silica precipitation from heated fluids have been analyzed and compared to laboratory rates. New sets of precipitation experiments are being planned. The microbially influenced degradation of concrete in the Broadlands-Ohaaki geothermal field is being characterized. The authors will continue to work on these projects in FY 1996 and expand to include the study of naturally occurring uranium and thorium series radionuclides, as a prelude to studying radionuclide migration in heated silicic volcanic rocks. 32 refs.

  10. Low temperature environmental degradation of zirconia ceramics

    Science.gov (United States)

    Zhao, Zhenbo

    2005-11-01

    The low temperature environmental degradation (LTED) of yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) has been prevented, or at least retarded, by using both bulk doping and surface doping methods with either cation, or anion, stabilizers. The introduction of both mullite and alumina into 3Y-TZP by a bulk-doping method was found to be effective in suppressing the tetragonal-->monoclinic transformation induced by water during hydrothermal treatment thus giving rise to better mechanical properties. The beneficial effects of alumina on the phase stability of the 3Y-TZP ceramic are considered to be due to the increase in the elastic modulus of the constraining matrix, as well as to the segregation of A12O3 at grain boundaries. The LTED transformation kinetics as determined by x-ray diffraction (XRD) and White Light Interferometer (WLI) analysis showed that the isothermal tetragonal-to-monoclinic transformation starts from the surface and has an incubation-nucleation-growth mechanism which can be described by the Johnson-Mehl-Avrami equation. The degradation of Y-TZP ceramic after hydrothermal treatment can be effectively overcome by surface doping by a solid diffusion method with tetravalent dopants: CeO2 and GeO2; with trivalent dopants: La2O 3 and Fe2O3; and with divalent dopants: CuO and MgO. For surface CeO2-, GeO2- and Fe2O 3-doping, this degradation inhibition behaviour is attributed to a localized increase in cation stabilizer content which satisfies the requirements for stabilization of the tetragonal phase. However, in each case, the stability mechanisms are different. For surface La2O3doping, surface doping overcomes the formation of La2O3 and La 2Zr2O7 since the extra La2O3 can further diffuse to the center of the 3Y-TZP ceramic. For CuO-doping, small amounts of CuO form a liquid that can act as a conduit for the re-distribution of yttria. In the case of surface MgO modification, the stabilization results from the isolated nature of the

  11. The Oregon Geothermal Planning Conference

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-10-02

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

  12. Geothermal tomorrow 2008

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2009-01-18

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

  13. Geothermal power development in Hawaii. Volume I. Review and analysis

    Energy Technology Data Exchange (ETDEWEB)

    1982-06-01

    The history of geothermal exploration in Hawaii is reviewed briefly. The nature and occurrences of geothermal resources are presented island by island. An overview of geothermal markets is presented. Other topies covered are: potential markets of the identified geothermal areas, well drilling technology, hydrothermal fluid transport, overland and submarine electrical transmission, community aspects of geothermal development, legal and policy issues associated with mineral and land ownership, logistics and infrastructure, legislation and permitting, land use controls, Regulation 8, Public Utilities Commission, political climate and environment, state plans, county plans, geothermal development risks, and business planning guidelines.

  14. Li-Ion Cell Development for Low Temperature Applications

    Science.gov (United States)

    Huang, C.-K.; Sakamoto, J. S.; Surampudi, S.; Wolfenstine, J.

    2000-01-01

    JPL is involved in the development of rechargeable Li-ion cells for future Mars Exploration Missions. The specific objectives are to improve the Li-ion cell cycle life performance and rate capability at low temperature (Li-ion rate capability at low temperature has been attributed to: (1) the electrolytes becoming viscous or freezing and/or (2) reduced electrode capacity that results from decreased Li diffusivity. Our efforts focus on increasing the rate capability at low temperature for Li-ion cells. In order to improve the rate capability we evaluated the following: (1) cathode performance at low temperatures, (2) electrode active material particle size on low temperature performance and (3) Li diffusivity at room temperature and low temperatures. In this paper, we will discuss the results of our study.

  15. Effectiveness of Low Temperature Additives for Biodiesel Blends

    Science.gov (United States)

    2012-06-30

    UNCLASSIFIED EFFECTIVENESS OF LOW TEMPERATURE ADDITIVES FOR BIODIESEL BLENDS INTERIM REPORT TFLRF No. 428 by Steven R...Do not return it to the originator. UNCLASSIFIED UNCLASSIFIED EFFECTIVENESS OF LOW TEMPERATURE ADDITIVES FOR BIODIESEL BLENDS...17-2010 – 06-30-2012 4. TITLE AND SUBTITLE Effectiveness of Low Temperature Additives for Biodiesel Blends 5a. CONTRACT NUMBER W56HZV-09-C-0100

  16. Geologic setting of the Central Alaskan Hot Springs Belt: Implications for geothermal resource capacity and sustainable energy production

    Science.gov (United States)

    Kolker, Amanda M.

    The Central Alaskan Hot Springs Belt (CAHSB) is a vast stretch of low-temperature hydrothermal systems that has the potential to be a geothermal energy resource for remote communities in Alaska. Little exploration has occurred in the CAHSB and the resource is poorly understood. A geothermal power plant was installed in 2006 at Chena Hot Springs (CHS), one of the 30-plus hot springs in the CAHSB. This, in addition to the multiple direct use projects at CHS, could serve as a model for geothermal development elsewhere in the CAHSB. This dissertation evaluates the geologic setting of the CAHSB and explores the implications for resource capacity and sustainable energy production. The local geology and geochemical characteristics of CHS are characterized, with a focus on identifying ultimate heat source responsible for the hot springs. A radiogenic heat source model is proposed and tested for the entire CAHSB, wherein the anomalously radioactive plutons that are associated with nearly every hot spring are providing the source of heat driving the geothermal activity. This model appears to be feasible mechanism for the observed heat transfer. This implies that CAHSB "reservoir" fluids are probably low-temperature. It also suggests that individual hydrothermal systems are small-scale and localized features, unlike the types of hydrothermal systems that are conventionally exploited for energy (i.e., those that derive their heat from magmatic or deep crustal sources, which have higher reservoir temperatures and larger spatial extent). In this context, the individual capacity of several CAHSB resources close to communities is assessed, and a preliminary evaluation of the sustainability of the power production scheme at CHS is given. As another approach to the question of sustainability, this dissertation explores the ways in which external benefits of geothermal energy can influence the economics of a project. In sum, producing geothermal energy from CAHSB resources is

  17. Low-Temperature Solution Processable Electrodes for Piezoelectric Sensors Applications

    Science.gov (United States)

    Tuukkanen, Sampo; Julin, Tuomas; Rantanen, Ville; Zakrzewski, Mari; Moilanen, Pasi; Lupo, Donald

    2013-05-01

    Piezoelectric thin-film sensors are suitable for a wide range of applications from physiological measurements to industrial monitoring systems. The use of flexible materials in combination with high-throughput printing technologies enables cost-effective manufacturing of custom-designed, highly integratable piezoelectric sensors. This type of sensor can, for instance, improve industrial process control or enable the embedding of ubiquitous sensors in our living environment to improve quality of life. Here, we discuss the benefits, challenges and potential applications of piezoelectric thin-film sensors. The piezoelectric sensor elements are fabricated by printing electrodes on both sides of unmetallized poly(vinylidene fluoride) film. We show that materials which are solution processable in low temperatures, biocompatible and environmental friendly are suitable for use as electrode materials in piezoelectric sensors.

  18. PbO-free glasses for low temperature packaging

    Energy Technology Data Exchange (ETDEWEB)

    Brow, R.K.; Bencoe, D.N.; Tallant, D.R. [and others

    1997-10-01

    Zinc polyphosphate glasses were examined as potential candidates for low temperature sealing applications. Glass-formation and properties were determined for the ZnO-P{sub 2}O{sub 5}, ZnO-B{sub 2}O{sub 3}-P{sub 2}O{sub 5} and ZnO-SnO-P{sub 2}O{sub 5} systems, and information about the short-range structures of these glasses was obtained by Raman and solid state nuclear magnetic resonance spectroscopies. In general, the most durable polyphosphate glasses have structures based on relatively short pyrophosphate chain lengths (i.e., 2 P-tetrahedra). Modified phosphate compositions are given, including compositions used to seal float glass substrates at temperatures as low as 500{degrees}C.

  19. Low temperature conversion of plastic waste into light hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Shah, Sajid Hussain; Khan, Zahid Mahmood; Raja, Iftikhar Ahmad; Mahmood, Qaisar; Bhatti, Zulfiqar Ahmad; Khan, Jamil; Farooq, Ather; Rashid, Naim [Department of Environmental Sciences, COMSATS Institute of Information Technology, Abbottabad 22060 (Pakistan); Wu, Donglei, E-mail: wudl@zju.edu.cn [Department of Environmental Engineering, Zhejiang University, Hangzhou 310029 (China)

    2010-07-15

    Advance recycling through pyrolytic technology has the potential of being applied to the management of plastic waste (PW). For this purpose 1 l volume, energy efficient batch reactor was manufactured locally and tested for pyrolysis of waste plastic. The feedstock for reactor was 50 g waste polyethylene. The average yield of the pyrolytic oil, wax, pyrogas and char from pyrolysis of PW were 48.6, 40.7, 10.1 and 0.6%, respectively, at 275 deg. C with non-catalytic process. Using catalyst the average yields of pyrolytic oil, pyrogas, wax and residue (char) of 50 g of PW was 47.98, 35.43, 16.09 and 0.50%, respectively, at operating temperature of 250 deg. C. The designed reactor could work at low temperature in the absence of a catalyst to obtain similar products as for a catalytic process.

  20. Conductive thermal modeling of Wyoming geothermal systems

    Energy Technology Data Exchange (ETDEWEB)

    Heasler, H.P.; Ruscetta, C.A.; Foley, D. (eds.)

    1981-05-01

    A summary of techniques used by the Wyoming Geothermal Resource Assessment Group in defining low-temperature hydrothermal resource areas is presented. Emphasis is placed on thermal modeling techniques appropriate to Wyoming's geologic setting. Thermal parameters discussed include oil-well bottom hole temperatures, heat flow, thermal conductivity, and measured temperature-depth profiles. Examples of the use of these techniques are from the regional study of the Bighorn Basin and two site specific studies within the Basin.