Pilgrim Hot Springs Geothermal g p g Resource Exploration

Pilgrim Hot Springs Geothermal Pilgrim Hot Springs Geothermal g p gResource ExplorationResource Exploration

Presented by:

Gwen Holdmann

Alaska Center for Energy and Power University of Alaska, Fairbanks

Pilgrim Hot Springs Geothermal Exploration Project Overview

• Grant from Department of Energy is stillGrant from Department of Energy is still pending ($4.6M for 2-1/2 years)

P i t t t i ti th l• Purpose is to test an innovative geothermal exploration technique

• Partnership between Geophysical Institute and Alaska Center for Energy and Powerand Alaska Center for Energy and Power

• USGS assessment parallel but separately f d d ff t

Cosmos, August 2008

funded effort

Desired Outcomes for Project:Desired Outcomes for Project:• Develop an inexpensive exploration p p p

technique that can be applied to other low temperature systems in Alaskap y

• Make a determination whether the site will be economic to develop either forwill be economic to develop, either for power delivery to Nome or other local beneficial usebeneficial use

Cosmos, August 2008

ACEP Current ProjectsACEP Current Projects

Geothermal Resources QualityGeothermal Resources Quality

Generation capacity per unit cost depends on severalGeneration capacity per unit cost depends on severalGeneration capacity per unit cost depends on several Generation capacity per unit cost depends on several geologic and economic factors:geologic and economic factors:

Temperature Temperature (hotter is better)(hotter is better)

Flow rateFlow rate (higher flow rates are better)(higher flow rates are better)

Reservoir FrameworkReservoir Framework (uniform porosity better than fractures)(uniform porosity better than fractures) Reservoir FrameworkReservoir Framework (uniform porosity better than fractures)(uniform porosity better than fractures)

RechargeRecharge (partially natural better than all artificial)(partially natural better than all artificial)

DepthDepth (shallower is less expensive, thus better)(shallower is less expensive, thus better)

Location, location,…Location, location,… (relative to population, transmission(relative to population, transmissionsystem, development costs, etc.)system, development costs, etc.)

Production/Injection Well Flow DiagramHow Geothermal Power is Generated

Production Well Injection Well

© Geothermal Education Office 2000

Chena Geothermal Power PlantChena Geothermal Power Plant

Pilgrim Hot Springs

Pilgrim Hot Springs• Original resource assessment conducted

1979-1982 by University of Alaska1979 1982 by University of Alaska

• Included a variety of ground based surveys

• Resulted in 6 closely spaced holes drilledResulted in 6 closely spaced holes drilled at site (150ft to 1000ft depth), temps as high as ~200⁰Fhigh as 200 F

• ‘Best estimate’ of 500MWth from resource

• Did not identify source of geothermal fluid

Upflow vs. Outflow Zonep

PowerPower Generation

fromfrom Geothermal ResourcesResources Worldwide

Pilgrim

Things we have learned since 1979:• Power can be generated economically for

resources as low as 165⁰Fresources as low as 165 F

• Distance fluid can travel underground between upflow zone and surface expression

• Cost of energy increasing (again)• Cost of energy increasing (again)

• Preliminary feasibility assessment of Nome energy options (2007, AEA, NETL), suggests geothermal is an economically viable option

Cosmos, August 2008

New Geothermal Exploration Project• Grant from Department of Energy is still

pending ($4 6M for 2-1/2 years)pending ($4.6M for 2 1/2 years)

• Purpose is to test innovative geothermal exploration technique

• Partnership between Geophysical InstitutePartnership between Geophysical Institute and Alaska Center for Energy and Power

• USGS assessment parallel but separately funded effort

Cosmos, August 2008

Work Plan and TimelineThermal Infrared Mapping and Analysis (Anupma Prakash Geophysical Institute(Anupma Prakash, Geophysical Institute

beginning summer 2010)

Cosmos, August 2008

Work grows out of prior research in mapping high temperature surface and subsurface coal fires

Cosmos, August 2008

Work grows out of prior research in mapping high temperature surface and subsurface coal fires

Cosmos, August 2008

Work grows out of prior research in mapping high temperature surface and subsurface coal fires

Cosmos, August 2008

Work Plan and TimelineRepair and collect new data from existing wells (summer 2010)wells (summer 2010)

Well PS-3

Well PS-1

Cosmos, August 2008

Work Plan and TimelineAdditional Ground based geophysical surveys - CSAMT shallow temperature mappingCSAMT, shallow temperature mapping (summer 2010)

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Work Plan and TimelineConceptual modeling and economic analysis (winter 2010-2011)(winter 2010 2011)

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Work Plan and TimelineGradient hole drilling program (2010-2011)

• 2-4 holes

• Approx 500 ftApprox. 500 ft depth

• Planned to try and pinpoint upflow zone

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Work Plan and TimelineConfirmation hole drilling program (2011)

• 2 holes

• Approx 2500 ftApprox. 2500 ft depth

• Confirm resource and innovative exploration techniques

Cosmos, August 2008

Reservoir ModelingMake predictions related to long-term development of the resource (winter 2011)development of the resource (winter 2011)

Cosmos, August 2008

www.uaf.edu/acepFor more information contact:

Gwen HoldmannOrganizational DirectorAl k C t f E & PAlaska Center for Energy & PowerUniversity of AlaskaTel: (907) 474-5402Tel: (907) 474-5402E-mail: Gwen.Holdmann@uaf.edu