WorldCat Identities

United States Department of Energy Geothermal Division

Works: 2,099 works in 2,580 publications in 1 language and 10,800 library holdings
Genres: Conference papers and proceedings  Handbooks and manuals 
Roles: Researcher, Sponsor
Publication Timeline
Most widely held works by United States
Geothermal progress monitor( )

in English and held by 183 WorldCat member libraries worldwide

Chemical tracer test at the Dixie Valley geothermal field, Nevada by Michael C. C Adams( Book )

1 edition published in 1993 in English and held by 180 WorldCat member libraries worldwide

Geothermal energy and the utility market : the opportunities and challenges for expanding geothermal energy in a competititive supply market by Geothermal Program Review( Book )

1 edition published in 1992 in English and held by 97 WorldCat member libraries worldwide

Geothermal Program Review XI : proceedings : "Geothermal Energy - the environmentally responsible energy technology for the nineties," April 27-28, 1993, Berkeley, CA by Geothermal Program Review( Book )

1 edition published in 1993 in English and held by 97 WorldCat member libraries worldwide

Geothermal financing workbook by Liz Battocletti( Book )

2 editions published in 1998 in English and held by 1 WorldCat member library worldwide

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

10 editions published between 1976 and 1996 in English and held by 0 WorldCat member libraries worldwide

The Olkaria geothermal field has been under continuous development since 1970. A feasibility study, completed in 1976, after six wells had been drilled and tested, indicated that development of the Olkaria field was feasible. The feasibility study was followed by production drilling and the construction of three 15 MW generating units. The first unit was brought on stream in July 1981, the second in December, 1982, and the third is scheduled to be completed in early 1985. The current output of 19 productive wells is equivalent to 46 MWe. Distribution of fumaroles and resistivity surveys indicate an areal extent of some 80 km² for the Olkaria geothermal field. Gas chemistry of fumaroles indicates comparable underground temperatures over the whole field, 200-250°C. The capacity of the resource has been estimated to be 500-1000 MW electric for a production period of 25 years. Most of the drilling has been confined to a small part of the geothermal field. Here maximum recorded downhole temperature is 339°C and temperatures follow the boiling point curve with depth. A thin steam zone at 240°C is observed in the top of the reservoir at approximately 600-700 m depth. The reservoir fluid is dilute, of the sodium chloride type, contains chloride in the range of 200-700 ppm. The reservoir rocks consist of a sequence of near horizontal lavas and tuffs of trachytic composition, but basaltic andesites have also beenidentified. The drilled rocks at Olkaria are of relatively low permeability, the average yield of wells being equivalent to about 2.5 MWe. Exploratory drilling is presently in porgress in the Olkaria field, the aim being to locate new production areas withing the field. Three holes have been completed and the forth and last hole under the present plan is being drilled
The Bulalo geothermal reservoir Makiling-Banahao area, Philippines( )

20 editions published between 1976 and 1996 in English and held by 0 WorldCat member libraries worldwide

Regular chemical sampling and analysis of fluids produced from the hot-water geothermal system of Cerro Prieto, Mexico has provided early warning of reservoir processes. The changes in chloride concentration, sodium to potassium ratio and measured fluid enthalpy are shown in the figures for wells M-5, M-26, M-21A, and M-11 of the Cerro Prieto field. The concentration of chloride, a ''conservative'' constituent, is characteristic of different water masses and is affected by a change of water source, by mixing of waters and by boiling and steam loss but not by reaction with rock minerals. The ratio of sodium to potassium is a temperature-sensitive geothermal index resulting from rock-water reaction and is not affected by boiling and steam loss or by mixing of water masses provided these processes occur at constant temperature. The enthalpy is related to the fluid temperature and to boiling in the aquifer with ''excess'' steam entering the well. These indices provide a reasonably complete picture of major reservoir processes occurring in hot water system. Silica analyses have not been reliable from Cerro Prieto but should be used in addition to Na/K as a temperature indicator. Analysis of fluids from a producing geothermal field must of course include other constituents for study of environmental effects, scaling, corrosion, etc
Geothermal resources of the eastern United States by J. L Renner( )

11 editions published between 1976 and 1982 in English and held by 0 WorldCat member libraries worldwide

The types of geothermal resources and their energy contents and producibility are reviewed. The production method and costs, production rates, and prerequisites of development are discussed. (MHR)
Future Well Testing and Injection at the East Mesa Field( )

19 editions published between 1976 and 1996 in English and held by 0 WorldCat member libraries worldwide

Retention processes such as adsorption and diffusion into an immobile region can effect tracer movement through a fractured reservoir. This study has conducted experimental work and has developed a two-dimensional model to characterize retention processes. A method to directly determine some important flow parameters, such as the fracture aperture, from the analysis of tracer tests has been developed as a result of the new two-dimensional model. The experimental work consisted of batch experiments designed to both reproduce earlier work and to determine the magnitude of the retention effects. Negligible retention was observed from which it was concluded that the batch experiments were not sensitive enough and that more sensitive flowing tests were needed. A two-dimensional model that represents a fractured medium by a mobile region, in which convention, diffusion, and adsorption are allowed, and an immobile region in which only diffusion and adsorption are allowed has been developed. It was possible to demonstrate how each of the mass-transfer processes included in the model affect tracer return curves by producing return curves for any set of the defining variables. Field data from the New Zealand was numerically fit with the model. The optimum values of the parameters determined from curve fitting provided a direct estimate of the fracture width and could be used to estimate other important flow parameters if experimentally determinable values were known. 25 refs., 22 figs., 6 tabs
Laboratory measurement of sorption in porous media by Stanford University( )

49 editions published between 1976 and 1996 in English and held by 0 WorldCat member libraries worldwide

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

12 editions published between 1978 and 1996 in English and held by 0 WorldCat member libraries worldwide

Dimensionless flowrate type curves were applied to steam wells at The Geysers in an attempt to quantify reservoir properties and to predict flowrate decline. Although data scatter was a problem, the flowrate data was smoothed by a normalization routine based on the back-pressure equation and the wells were modeled by dimensionless functions for a radial system with a infinite or finite outer boundary and a constant pressure inner boundary (composite analytical-empirical type curve). The "match" resulted in a unique D{sub i} value for use in Arps' equation and a permeability-thickness product (kh) comparable to kh values obtained from pressure buildup analysis. Finally, it was shown that at least four years of data is required to obtain a unique b value. 2 tabs., 12 refs., 12 figs
The U.S. Hot Dry Rock Project( )

15 editions published between 1976 and 1995 in English and held by 0 WorldCat member libraries worldwide

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

13 editions published between 1976 and 1996 in English and held by 0 WorldCat member libraries worldwide

We conducted feasibility studies of gravity monitoring based upon reservoir simulation. At first, actual field data (although slightly modified) were used for constructing the conceptual model of a geothermal reservoir, particularly for shallow geothermal reservoir case study. Then the possibility of gravity monitoring was confirmed. Secondly, in order to study the possibility of this for deep geothermal reservoir, we constructed simplified models for deep reservoir. Three models were prepared for our feasibility studies. These simulations showed us that we could also get fairly positive results, if we apply a very sensitive and stable gravity monitoring system. As a next step, we will investigate gravity monitoring systems according to our feasibility studies
Future target for geothermal development -- Fractal Fracture Mechanics and its application to conceptual HDR reservoir design( )

28 editions published between 1976 and 1996 in English and held by 0 WorldCat member libraries worldwide

Well test analysis offers a rapid way to perform an initial assessment of geothermal systems. Well testing includes both pressure drawdown and buildup testing, and interference testing. Development of new well test analyses receives major emphasis in the Stanford Geothermal Program. During the year, quite a few studies were completed, and reports and papers presented on a variety of well test analysis methods. The paper summarizes some of the more important results
A New Derivative Type-Curve for Pressure Buildup Analysis with Boundary Effects( )

38 editions published between 1976 and 1996 in English and held by 0 WorldCat member libraries worldwide

White, Muffler, and Truesdell (1971) and Truesdell and White (1973) developed a conceptual model of transport in vapor-dominated geothermal zones. The main theme of the model is that coexisting liquid and vapor phases form a counterflowing convection system similar to that observed in a heat pipe (Dunn and Reay, 1976). It is hypothesized that water evaporates from a deep water table, passes upward through the formation, and condenses at an impermeable cap rock, effectively transferring the latent heat of boiling through the formation. The liquid water then percolates downward, completing the cycle. The physics involved in the flow system is illustrated in an analysis of an idealized one-dimensional, homogeneous, 2 km deep vapor-dominated zone which is bounded below by a water table which has a temperature of 236°C. Flow of water and steam in the system is assumed to be described by Darcy's law for unsaturated porous materials. The liquid water potential, defined as the Gibbs free energy per unit volume of water, is used in place of the liquid pressure in the equation for water because flow in a highly unsaturated medium is to be considered. Comparison of figures 2 and 4 illustrates that the liquid saturation in a two-phase convection system can be much higher than that predicted from a static pressure analysis. As a result, the "vapor pressure lowering" effect expected in a static system disappears. The decrease in P{sub V} at the top of figure 4 is caused by temperature decrease; the relative vapor pressure in the dynamic system is above 99%. However, the permeability used in this example is very low. At higher permeabilities the condensing steam drains out of the system much faster, and the saturation approaches the static profile. 5 refs., 4 figs
Geothermal resource assessment in Oklahoma : modification of a report prepared for U.S. Department of Energy, Division of Geothermal Energy, under contract no. DE-AS07-80ID12172, October 1981 by William E Harrison( )

52 editions published between 1971 and 1993 in English and held by 0 WorldCat member libraries worldwide

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

15 editions published between 1976 and 1996 in English and held by 0 WorldCat member libraries worldwide

We previously reported (Zais, 1979) that Arps's exponential equation works quite well on geothermal production data. The hyperbolic equation should probably not be used. In this paper we show the progress made i n using influence functions t o describe reservoir production behavior
Significant Silica Solubility in Geothermal Steam( )

16 editions published between 1976 and 1996 in English and held by 0 WorldCat member libraries worldwide

In this paper, Boundary Element (BEM) solutions were obtained for the transient flow of fluids through homogeneous, anisotropic porous media. The Green's function method with Euler method of forward time differencing and Laplace transform method have been used by previous authors. Unlike these methods, this paper uses the fundamental solution to the differential equation and the convolution behavior of the resulting integrals to obtain an implicit and stable solution. This allows large time steps to be taken without significant loss in accuracy. Comparison with the Laplace transform method and Green's function method with discrete time stepping, for two test cases, show that the method is very accurate. The computations however, become quite storage intensive owing to the dynamic increase in the number of stored matrices. It has been shown elsewhere that for certain problems with both Dirichlet and Neumann boundary conditions, asymptotic expression generated from exact solution is needed for starting the computational procedure. The present formulation alleviates this requirement. These solutions are developed for use in the analysis of pressure transients in complex reservoir problems
Reservoir and injection technology : Geothermal reservoir engineering research at Stanford by Henry J Ramey( )

19 editions published between 1976 and 1996 in English and held by 0 WorldCat member libraries worldwide

We report results of steam adsorption experiments conducted for rock samples from vapor-dominated geothermal reservoirs. We examine the effect of the temperature on the adsorption/desorption isotherms. We find that the temperature effect is only important on the desorption such that the hysteresis becomes more pronounced as the temperature increases. The scanning behavior within the steam sorption hysteresis loop is also studied to investigate the behavior during repressurization. Collection of sets of data on the sorption behavior of The Geysers geothermal field in California is presented
Current techniques in acid-chloride corrosion control and monitoring at The Geysers( )

19 editions published between 1977 and 1996 in English and held by 0 WorldCat member libraries worldwide

We have presented a preliminary analysis of permeability structure and fluid and heat flow conditions in the deeper horizons of the Larderello geothermal system. Our main observations and findings are: (1) Measurements in deep Larderello wells have indicated formation temperatures near 300 º C at 3000 m depth, and even higher temperatures at greater depth. (2) From an analysis of heat transfer mechanisms we suggest that a transition from vapor-dominated to liquid-dominated conditions must have been present in the natural state of the Larderello geothermal system. No reliable determination of the depth at which this transition occurred has yet been made, but a depth of approximately 2000 m or more appears most likely. (3) From temperature-depth data in two-phase reservoirs it is in principle possible to estimate vertical permeability. (4) For exploited reservoirs such as Larderello, reconstruction of permeability and temperature trends with depth can be made indirectly, using numerical simulation. Our preliminary results indicate that production of high-enthalpy fluids can be explained from two-phase flow effects in a fractured-porous medium. 18 refs., 2 tabs., 7 figs
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Alternative Names

controlled identityUnited States. Department of Energy. Geothermal Technology Division

controlled identityUnited States. Department of Energy. Office of Conservation and Renewable Energy

controlled identityUnited States. Department of Energy. Office of Energy Efficiency and Renewable Energy

controlled identityUnited States. Department of Energy. Office of Geothermal Technologies

United States. Department of Energy. Office of Conservation and Renewable Energy. Geothermal Division

United States. Department of Energy. Office of Energy Efficiency and Renewable Energy. Geothermal Division.

United States. Dept. of Energy. Geothermal Division

English (343)