Geothermal Resources ofCalifornia: Moving from Assessments towards DevelopmentColin F. Williams

USGS, Menlo Park, CA

U.S. Department of the InteriorU.S. Geological Survey

Geothermal Resources ofCalifornia: Moving from Assessments towards Development

Sean Hagerty, Bureau of Land ManagementSean Hagerty, Bureau of Land Management Jim Lovekin, GeothermExJim Lovekin, GeothermEx Marshall Reed, US Geological SurveyMarshall Reed, US Geological Survey

Idealized Geothermal Power PlantIdealized Geothermal Power Plant

Need: Heat (Temperature) and Fluid (Permeability)Need: Heat (Temperature) and Fluid (Permeability)

GEA 1999GEA 1999

Some Terminology

Geothermal Resources are characterized by the degree of Geothermal Resources are characterized by the degree of

knowledge (e.g., discovered vs. undiscovered) and knowledge (e.g., discovered vs. undiscovered) and economic/technological feasibility.economic/technological feasibility.

Resource – Resource – The portion of the resource base that can be The portion of the resource base that can be recovered as useful heat under current and potential recovered as useful heat under current and potential economic and technological conditions.economic and technological conditions.

Reserve - Reserve - The identified portion of the resource that can be The identified portion of the resource that can be recovered economically using existing technology. recovered economically using existing technology.

Status of California Geothermal

At one point approximately 2800 MWe installedAt one point approximately 2800 MWe installed Currently >2000 MWeCurrently >2000 MWe 1978 USGS Resource Assessment 1978 USGS Resource Assessment

12,000 MWe in identified systems12,000 MWe in identified systems >10,000 MWe in undiscovered systems>10,000 MWe in undiscovered systems

2004 Resource Assessment - Geothermex2004 Resource Assessment - Geothermex >5000 MWe in identified, conventional resources>5000 MWe in identified, conventional resources

Largest resource in U.S., both installed and in Largest resource in U.S., both installed and in potential developmentpotential development

Developments in Geothermal

1.1. Temperature >200Temperature >200ooF(95 F(95 ooC) and Depth >10,000ft (3 km) for C) and Depth >10,000ft (3 km) for

power productionpower production

2.2. New systems discoveredNew systems discovered

3.3. Improved techniques for characterizing reservoirsImproved techniques for characterizing reservoirs

4.4. Increasing use of injection to sustain productionIncreasing use of injection to sustain production

5.5. Development of Enhanced Geothermal Systems (EGS) Development of Enhanced Geothermal Systems (EGS) technologytechnology

6.6. Potential for more accurate estimates of undiscovered Potential for more accurate estimates of undiscovered resourcesresources

Future Directions

Comprehensive Resource AssessmentsComprehensive Resource Assessments Combine National, State and Local Information in a Single Combine National, State and Local Information in a Single

Coherent ProductCoherent Product

Confirmation of ResourceConfirmation of Resource Refined Land Use PlansRefined Land Use Plans ExplorationExploration Continuing Development of EGS TechnologyContinuing Development of EGS Technology New and Unconventional ApplicationsNew and Unconventional Applications

HydrogenHydrogen Local Use in Urban AreasLocal Use in Urban Areas

Geothermal Power Development in Western States with Estimated Resources Greater than 100 MW - Electrical

0

3000

6000

9000

12000

AK AZ CA HI ID NV NM OR UT

Installed (2001)

Estimated Resource(1978)