# Presentation: 546937

## DOE Geothermal Research

***Geoscience and Related Technology***
***Exploration and Drilling***
***Energy Systems Research & Testing***

## Programmatic Objectives

***Decrease the cost of power***
***Increase geothermal use - electrical and direct use***
***Increase states with electrical generation***
***  ***

## DOE Geoscience

***Research to reduce cost of electricity and expand geothermal use***
***Improved exploration***
***Better engineering***
***Technology transfer/Industry collaboration****** ***

## DOE Geoscience

***Resource Enhancement***
***Exploration Technology Development***
***Geothermal Resource Exploration and Definition (GRED)***
*** ***

## Resource Enhancement

***Develop an adequate understanding of geothermal systems in order to find (in conjunction with the Exploration program element), enhance, and engineer geothermal systems***
***Provide updated estimates of the geothermal resources available for development in the United States in conjunction with USGS****** ***

## Resource Enhancement

***Improve the efficiency and sustainability of energy recovery from geothermal systems by engineering of natural and stimulated natural geothermal systems***
***Carry out a cost-effective research and development program so that industry can make decisions about using EGS systems.***

## Exploration

*** ***
***Develop and test innovative techniques for exploring for geothermal resources***
*** ***
***Reduce the cost of drilling through improved well-siting by applying new exploration and characterization techniques  ***

## Geothermal Resource Exploration and Definition (GRED) 

***Industry cost-shared exploration projects***
***	******To find, evaluate, and define additional geothermal resources throughout the western United States***

## Research Team

***National Laboratories - INEEL, LBNL, LLNL***
***Universities***
***Industry partners - EGS and GRED***** **

## Research topics

***Geochemistry***
***Geology***
***Exploration Models***
***Geophysical Tools for Resource Characterization, Exploration and Monitoring***
***Resource Analysis****** ***
***Reservoir Engineering****** ***
***Reservoir Characterization & Management***
***Production and Injection Strategies***
***Rock Mechanics ***
***Thermoelastic Hydraulic Fracture Design***
***Tracers***

## Slide 11

## INEEL Geoscience Activities

**J.L. Renner**

## INEEL Geoscience

- Research supporting resource enhancement and exploration
- Objectives:
- Develop reservoir engineering tools
- Hydrothermal systems
- Engineered systems (EGS)
- Investigate improved exploration methods

## EGS &Hydrothermal Characterization 

**Objective:  Develop methods to identify permeability structure, anisotropy, and flow volume for engineered and fluid-starved systems.**
**Approach:  **
**Extend Tracer Test Analysis to fractured media**
**Develop tracer selection criteria.**

## Existing Tracer Test Interpretation Problems (from Maxfield et al., 2003)

**Tracer is retarded (adsorbed) as moisture content of sandpack decreases.  Cannot interpret tracer test results correctly if superheated conditions prevail.  We need better tracer selection criteria.**

## Injection into Fluid-Starved Environments

**Objective:  Determine optimal use of injectate by studying relative influence of:**
**	****- Liquid saturation**
**	****- NCG concentration**
**	****- Power generation efficiency.**
**Approach:  Extend work of Truesdell and Shook (1997), Stark (2001) by numerically simulating injection into HTR vs. NVDR in NW Geysers. **

## Example:  Effect of Injection Location on NCG Production

**Injection just above the HTR results in complete boiling of injectate without high concentrations of NCG.**

**Injection within the HTR doesn’t add to production rate, but does create a NCG bank.  Higher NCG production reduces generation efficiency by 7%.**

## Improved Numerical Tools

**Objective:  Develop improved numerical tools.**
**Approach:  **
**	****- New Wellbore flow correlation (SAIC)**
**	****- Inverse Model for Tetrad – Tet****-1**** (INEEL)**
**	****- Integrated Reservoir and Geophysics models –**
**TetGeo (collaborative project, RFP outstanding)**
**	****- TetGeo****-1**** in FY04.**

## Multi-phase Flow Correlation

**Developing new steam-water correlations for high, medium, and low enthalpy well data provided by Unocal, CalEnergy, SAIC.  **
**Available for ALL wellbore simulators in FY04.**

## Automatic History Matching (Inverse Modeling) 	– Tet-1

**Public Domain Inverse Model PEST Coupled to Tetrad**
**Tet****-1**** executes multiple commands; easy to extend to (TETRAD + Geophysics) model**
**Strong Industry Support (Caithness, CalEnergy, Unocal, SAIC, Stanford U, etc.)**
**Available for beta-test April 2003.**

## Coupled Reservoir Plus Geophysics	TetGeo and TetGeo-1

**Integrating models increases observations**
** ****more data reduces uncertainty**
**Field Management AND Exploration Tool**
**Extend TetGeo to TetGeo****-1**** in FY04.**

## New Exploration Strategies in the B&R

**Aeromag surveys as an exploration tool**
**Demonstrated utility in locating faults at DV**
**Inexpensive, rapid means of regional analysis**
**Combined with heat flow, geologic mapping gives more precise description of resource.**

## Dixie Valley Aeromag and Mapped Faults

**Faults inferred from Maximum Horizontal Gradient in gravity (shaded relief) correlate with mapped faults (yellow lines).  From Smith, 2003.**

## Soda Lake

**Occurs in Carson Sink where active resurfacing obscures surface evidence of faults**
**Recent (~10ka) volcanism**
**Potential dike and/or other basalt intrusion**
**Relationship of geothermal system to faults and intrusions is not known**
**High-resolution aeromag particularly useful because of active deposition and young volcanism.**

## Applying ‘Lessons Learned’ from Dixie Valley – B&R data constructs

**Evaluating the importance of the DV studies:**
**Synthesis of available spatially referenced data for known B&R systems**
**Development of overlays (thematic layers) of geologic, geochemical, and geophysical data**
**Analysis to discover most important exploration criteria, most important surveys to perform**
**Selection of additional areas for future exploration.**

## Miscellaneous

- Prepare synthesis of Dixie Valley research
- Assist USGS with exploration data collection
- High temperature  probe
- Support geoscience program

## INEEL Accomplishments

- A suite of reservoir simulation methods
- To be used with existing simulators
- To better characterize geothermal fields
- Improved injection practices
- Cost effective exploration methods