Enhanced Geothermal SystemsJASON The MITRE Corporation 7515 Colshire Drive McLean, Virginia 22102-7508 (703) 983-6997JSR-13-320December 2013Approved for public release; distribution unlimited.Contact: Dan McMorrow dmcmorrowmitre.orgREPORT DOCUMENTATION PAGE Form Approved OMB No. 0704-0188 Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing this collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) December 2013 2. REPORT TYPE Technical 3. DATES COVERED (From - To) 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Enhanced Geothermal Systems 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 13139022 R. Jeanloz, H. Stone et al. 5e. TASK NUMBER PS 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER The MITRE Corporation JASON Program Office 7515 Colshire Drive McLean, Virginia 22102 JSR-13-320 9. SPONSORING / MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITORS ACRONYM(S) US Department of Energy Energy Efficiency and Renewable Energy 1000 Independence Ave, SW 11. SPONSOR/MONITORS REPORT Washington, DC 20585 NUMBER(S) 12. DISTRIBUTION / AVAILABILITY STATEMENT Approved for public release 13. SUPPLEMENTARY NOTES 14. ABSTRACT DOE, through the Geothermal Technologies Office (GTO) within the Office of Energy Efficiency and Renewable Energy, requested this study, identifying a focus on: i) assessment of technologies and approaches for subsurface imaging and characterization so as to be able to validate EGS opportunities, and ii) assessment of approaches toward creating sites for EGS, including science and engineering to enhance permeability and increase the recovery factor. Two days of briefings provided in-depth discussion of a wide range of themes and challenges in EGS, and represented perspectives from industry, government laboratories and university researchers. JASON also contacted colleagues from universities, government labs and industry in further conversations to learn the state of the field and potential technologies relevant to EGS. 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON Mr. Douglas Hollett a. REPORT Unclassfied b. ABSTRACT Unclassified c. THIS PAGE Unclassified UL 19b. TELEPHONE NUMBER (include area code) 703-746-1453 Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. Z39.18 Contents1EXECUTIVE SUMMARY12INTRODUCTION5 2.1Study Charge and Process . . . . . . . . . . . . . . . . . . . .93ESTIMATES OF U.S. GEOTHERMAL RESOURCE11 3.1Geological Setting . . . . . . . . . . . . . . . . . . . . . . . . .11 3.2Resource Estimates . . . . . . . . . . . . . . . . . . . . . . . .12 3.3Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .194IMAGING AND CHARACTERIZATION23 4.1Ambient-Field Seismic Imaging. . . . . . . . . . . . . . . . .24 4.2Nonlinear Elastic Response . . . . . . . . . . . . . . . . . . . .27 4.3Drilling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31 4.3.1Conventional holes . . . . . . . . . . . . . . . . . . . .31 4.3.2“Microholes”. . . . . . . . . . . . . . . . . . . . . . .32 4.3.3Resonant drilling . . . . . . . . . . . . . . . . . . . . .34 4.3.4Fluid injection drilling . . . . . . . . . . . . . . . . . .35 4.3.5High-speed dual string drilling . . . . . . . . . . . . . .36 4.3.6Summary. . . . . . . . . . . . . . . . . . . . . . . . .37 4.4Physical Description and Time Evolution of an EGS Reservoir37 4.4.1Some characteristic scales of the crack network for flow and heat transfer . . . . . . . . . . . . . . . . . . . . .39 4.5Tracer Experiments and Models . . . . . . . . . . . . . . . . .42 4.5.1Breakthrough curves from tracer studies . . . . . . . .43 4.5.2Order-of-magnitude estimates for the breakthrough curves 47 4.5.3Analyzing tracer breakthrough curves with a one-dimensional model. . . . . . . . . . . . . . . . . . . . . . . . . . .48 4.5.4The dispersion produced by a network of cracks . . . .51 4.6Electromagnetic Imaging of Permeability . . . . . . . . . . . .51 4.7Enhanced Subsurface Validation Made Possible by Micro Drilling 535EGS CR