Jay NathwaniU.S. Department of EnergyIdaho Operations OfficeMarch 20, 2003

DOE Financial Assistance Programs

GrantsUniversity Research Area

Kansas State University – Daniel Swenson EGS

New Mexico Technology Institute – James C. Witcher Exploration

Pennsylvania State University – Peter Heaney ESR&T

Southern Methodist University – David Blackwell Exploration

Stanford University – Roland Horne Reservoir Engineering

University of California – San Diego – Nancy Moller Fundamental Research

University of Nevada – Reno – Lisa Shevenell EX & EGS

University of North Carolina – Jose Rial EGS & Reservoir Engineering

University of North Dakota – Ahmad Ghassemi EGS

University of Utah – Energy and Geoscience Institute

Task 1 – Jeff Hulen

Task 2 – Joe Moore

Task 3 – Greg Nash

Task 4 – Phil Wanamaker

Task 5 – Mike Adams

Task 6 – Pete Rose

Fundamental Science

Fundamental Science

Exploration Technology

Exploration Technology

Tracer R&D

EGS

University of Wisconsin – David L. Alumbaugh Exploration

Type of Research

• Reservoir Characterization & Management• Remote Sensing and Imaging Tools• Exploration Models• Resource Analysis• Thermoelastic Hydraulic Fracture Design• Production and Injection Strategies• Permeability• Tracers• Gas Analysis of Geothermal Fluid Inclusions

Status

• 27 current research projects – 15 in a process of closeout

• Last solicitation was announced in July 2002– 22 proposals received – 4 new projects selected for funding– 5 projects selected for possible future funding

• FY2003 commitments– $3,565K for current research proposed– $0K for new research– $2,600K Earmark by congress

• Future Solicitation in FY2004

Field Studies of Geothermal Reservoirs Rio Grande Rift, NM

James C. WitcherNew Mexico State University

AchievementsIdentified Common Structural Settings of Rift Reservoirs

• Structurally-high bedrock uplifts at low surface elevation• Regional aquitards removed by erosion or faulting• Pre-rifting basement control (Mesozoic compressional and

transpressional structures)• Transfer zones at fault, graben, and rift scales• Post mid-Miocene structural inversion

Benefits and Use• First-order hydrogeologic exploration model• Framework for blind reservoir discovery• Locate best drill targets at known reservoirs

A Geochemical and Microanalytical Study of Silica Scale Deposition in Geothermal Brines

Peter HeaneyPenn State

Achievements• Examined the rates of silica condensation and precipitation in

supersaturated solutions using brine chemistries suggested by the Geothermal Power and Operations section of Unocal.

• Relationships between silica concentration, pH, and ionic strength have been incorporated into computer models used by engineers at Unocal for assessing brine behaviors in new systems.

• Explored the nature of the silica complexes formed with simple alcohol-rich molecules using molecular dynamical simulation methods with the program Cerius2.

• Compared the rates of silica condensation and precipitation in solutions with and without dissolved sulfite, a potential silica scale inhibitor.

• Investigate the growth and stability of colloidal silica using gel filtration chromatography, ultrafiltration, atomic force microscopy, transmission electron microscopy, and light scattering analysis.

Benefits and Use• Publications

Application of Thermal Techniques for Exploration and Assessment of Basin and Range Geothermal Resources

David BlackwellSMU

Achievements

• Thermal and drilling data from the Dixie Valley Geothermal Field

• Geophysical surveys of Dixie Valley including gravity and aeromagnetics and integrated the geophysical, seismic, geological and drilling data at Dixie Valley into local and regional geologic models

• Natural state mass and energy transport fluid flow models of generic Basin and Range systems based on Dixie Valley data

• Relation between natural heat loss for geothermal and electrical power production potential and determined heat flow for 27 different geothermal systems

• Developed web based data base including information from over 5,900 geothermal exploration wells

Benefits and Use

• Publications

Laboratory Measurements of Properties for Steam/Water Flow in Geothermal Rocks

Roland HorneStanford

Achievements

• Measurement of multiphase flow properties of geothermal rocks under boiling conditions.

• Fundamental study of flow in fractures, in support of the development of techniques to optimize production and reinjection design.

• Development of methods to determine reservoir saturation from surface measurements.

Benefits and Use

• Improved resource recovery and effectiveness.

• Methodology to reduce the uncertainty of reservoir performance calculations

• Clearer predictions of the remaining life of the reservoir for planning purposes

• Stanford Workshop

• Publications

Technology for Increasing Geothermal Energy Productivity

Nancy Moller-Weare an John WeareUCSD

Achievements• TEQUIL: Comprehensive models of solid-liquid-gas equilibria

in the H-Na-K-Ca-OH-Cl-HSO4-SO4-HCO3-CO3-H4SiO4o-H3SiO4--H2O-CO2(g)-SiO2 system to high brine concentration and temperature (< 300°C).

• GEOFLUIDS: New equation of state models for supercritical applications that can accurately predict multiple phase conditions, critical behavior and PVTX properties of compressible fluids in the system, salt--CO2-CH4-H2O.

• GEOHEAT: Enthalpy models of NaCl-H2O brines (T < 300°C) and H2O-CO2-CH4 gas phases.

Benefits and Use• Interactive web site, GEOTHERM.UCSD.edu, and user

interface software. • Publications

Great Basin Center for Geothermal Energy

Lisa ShevenellUNR

Achievements

• Predicted the spatial trends of known high temperatures using GPS

• Enhanced understanding of the subsurface geologic framework of the Hot Springs Mountains, including depth to basement and geometry of faults

• A regional geophysical database supporting the exploration for new, hidden geothermal fields has been initiated with a resolution of 8 km, which was supplemented by a successful deep seismic sounding experiment

Benefits and Use

• In 2002, the funded projects led to 14 technical publications, and nine presentations at the annual GRC meeting plus five additional presentations in other venues.

• Collaborations with industry partners

• Publications

Characterization of Fracture Patterns in the Geysers Geothermal Field

Jose RialUNC

Achievements

• Compiled the largest and most complete data set on shear-wave splitting parameters (fast shear-wave polarization and differential time delay pairs) in the world, from micro-earthquake seismic records recorded at The Geysers and Coso geothermal fields.

• Constructed 3D maps showing fracture patterns and crack densities under all the array stations at The Geysers and Coso.

• Developed and implemented a Matlab-based, interactive, graphics-oriented inversion computer code for shear-wave splitting data processing, measurement of split parameters, forward modeling and inversion of crack-induced anisotropy.

• Inverted shear-wave splitting parameter data sets to obtain subsurface crack geometry and crack densities in NW and SE Geysers and in selected stations at Coso.

Benefits and Use

• Publications

Thermoelastic Hydraulic Fracture Design Tool

Ahmad GhassemiUND

Achievements

• Analysis of fracture initiation from a wellbore

• Development of a two-dimensional boundary element code for modeling fracture propagation;

• Theoretical study of fluid flow and heat exchange in induced fractures and related stresses (2D and 3D)

• Integration of the analytic and numerical algorithms into a user-friendly software package

Benefits and Use

• Quantitatively consider fracture propagation for development of EGS, including the influence of faults on fracture direction

• Study influence of cooling on stress distribution and fracture slip/propagation

• Guide drilling strategies

• Publications

Improved Conceptual Modeling of High-Temperature, Western U.S. Geothermal Systems

Jeff HulenUniversity of Utah - EGI

Achievements• Refine and develop new conceptual geological,

geochemical, and numerical models for magmatically-heated and “deep circulation” systems

• Discovered and mapped a huge region of pervasive, mineralized but interconnected and permeable natural hydraulic fractures in the proposed 185 MWe “Unit 6” development area at the Salton Sea field.

• Discovered that much of the shallow “quartzite” at the Dixie Valley field is actually silicified, gold-bearing alluvium

Benefits and Use• Industry partners• 26 Publications

Improving Exploration Models of Andesite-Hosted Geothermal Systems

Joe MoreUniversity of Utah - EGI

Achievements• Showed how and why volcanic-hosted vapor-dominated systems form • Characterized permeability evolution and controls on permeability in a

volcanic-hosted system

Benefits and Use• 3 industry partners• 20 Publications

Improved Technologies for Geothermal Resource Evaluation

Greg NashUniversity of Utah - EGI

Achievements• Dixie Valley, NV: Hyperspectral

mineralogy/soil mineral anomaly study completed

• Cove Fort-Sulphurdale, UT: Vegetal-spectral anomaly/structure correlation study completed

• Dixie Valley, NV: Thermal infrared study completed

• The Geysers, CA: Three high-precision gravity and GPS field campaigns completed

• Great Basin: Code developed to facilitate semi-automated extensional-tectonic geomorphometric calculations

• Web-based GIS setup for technology transfer and data distribution

Benefits and Use• 12 Publications

Enhanced TIR image - thermal anomalies appear as light areas. TIR data is useful in exploration, hydrologic studies, and field monitoring.

EM Geophysics

P. WannamakerUniversity of Utah - EGI

Achievements• Development, testing and

use of MT and DC inverse algorithms

• Monitoring of production-induced changes; 3-D algorithm development with industry

• Implementation of 2-D and 3-D codes on clusters

• New-generation MT field system

Benefits and Use• 14 Publications

Thermal Stability of Naphthalene Sulfonate Tracers

Tracing Geothermal Fluids

Mike AdamsUniversity of Utah - EGI

Achievements• Developed HFC vapor-

phase tracers

Benefits and Use• Publications and one

special volume of Geothermics resulting from this task

• Throughout The Geysers

THE DEVELOPMENT OF TOOLS FOR MANAGING INJECTION IN GEOTHERMAL RESERVOIRS

Pete RoseUniversity of Utah - EGI

Achievements• Developed 8 very

detectable naphthalene sulfonate tracers for tracing flow in liquid dominated reservoirs to temperatures > 340oC.

Benefits and Use• 16 Publications

Thermal Stability of Naphthalene Sulfonate Tracers

Jay NathwaniU.S. Department of EnergyIdaho Operations OfficeMarch 20, 2003

Geothermal Technologies

Program

Enhanced Geothermal

Systems (EGS)

Enhanced Geothermal Systems

• Engineered Geothermal Reservoir– Improves circulation and productivity

– Improves permeability

– Extends reservoir life

EGS Portfolio

I. Existing geothermal plant with additional generating capability

II. Separate generating facility adjacent to a known Geothermal Resource Area

III. Stand alone in an area with no existing geothermal development

EGS Status

• Solicitation I (April 2002)– Coso/EGI project downselected from 13 proposals

• China Lake Naval Air Weapon Station, CA• Additional 20 MW(e) production• $12M project with $4.5M DOE share (38-62)

• Solicitation II (July 2002)– Calpine

• Glass Mountain, CA• New 49 MW(e) plant• $425K for Phase II (60-40)

– ORMAT• Desert Peak East, NV• New 3-5 MW(e) plant• $464K for Phase I (80-20)

• Solicitation III (FY2005)

EGS I – Solicitation 2000

Coso/EGI project downselected from 13 proposals•China Lake Naval Air Weapon Station, CA•Additional 20 MW(e) production•$12M project with $4.5M DOE share

EGS II – Solicitation 2002

Calpine•Site selection not made•New 49 MW(e) plant•$425K for Phase II

ORMAT•Desert Peak East, NV•New 3-5 MW(e) plant•$360K for Phase I

Other EGS related Projects

• Injection Projects

•Geyser Basin Recharge Project

•Santa Rosa Pipe Line

The Coso EGS Study Area

The Coso EGS Concept

Description: Create and test an EGS through thermal and hydraulic stimulation. Understand the creative process of thermal and hydraulic stimulation.

Ultimately enhance the current geothermal power production by 20MWe.

Partners: Coso Operating Company (COC)United States Geological Survey (USGS)Geomechanics International (GMI)Kansas State University (KSU)Halliburton Energy SystemsTerraTekQuantecQ-con

The Coso Status

• Completed a preliminary analysis of the stress state of the EGS study area (This is needed in order to develop a predictive model about the likelihood of success of a stimulation experiment.)

• Completed an injection study including a microseismics analysis of a candidate EGS injection well (This is a first step in an EGS task to determine the relative importance of thermal and chemical effects on injectivity.)

• Completed a detailed petrographic, petrologic and fluid-inclusion analysis of drill cuttings from several Coso/EGS study wells (This is important for recognizing the geologic conditions that will result in a successful stimulation experiment.)

ORMAT Concept

Description: Define important technical and economical parameters crucial to cost-effective commercial development of EGS Geothermal Power Plant.Create and test an EGS reservoir at Desert Peak East that is capable of sustaining the operation of a power plant power, delivering up to 10 MWe to a utility or other power consumer.

Partners: GeothermEx

ORMAT Status

• Petrologic work has confirmed the correlation between the

cuttings and core from two wells within the EGS area

separated by approximately a mile.

• Thin section and XRD work has defined multiple intervals of

granitic intrusion in the area and is developing an geologic

history for the area.

• This information will be used in refining the target fracture

simulation zones in Phase II of the project.

Calpine Concept

Description: Apply known and new well permeability enhancement techniques to reduce the number of wells needed and demonstrate the applicability of the techniques to other undeveloped or under-developed fields.

Develop a reservoir that is capable of producing up to 49MW EGS geothermal electrical power.

Partners: Calpine and Halliburton

Calpine Status

• Identified production wells at the Geysers and Glass Mountain

that may be suitable for stimulation by acidizing and/or high-

rate injection.

• Updating Glass Mountain exploration and development

permits to include acidizing operations.

Geysers Production and Injection History

Calpine Unit Areas Total

Lake County Basin Geothermal Project

Description: Expansion of an existing pipeline to provide additional treated municipal wastewater to The Geysers

DOE 2002 Funds: $1,873,000 (earmark of $2 million with Congressionally-approved reductions)

Partners: Calpine, NCPA, Lake County

Santa Rosa Geysers Project

Description: Construction of a 40-mile pipeline to provide treated municipal wastewater to northern part of The Geysers

DOE 2002 Funds: $1,873,000

Partners: City of Santa Rosa and Calpine