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Geothermal Basics: Q&A September 2012 Are You a GEA Member?

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Geothermal Basics: Q&A September 2012 Are You a GEA Member? Geothermal Basics: Q&A September 2012 Are you a GEA member? What is GEA?: The Geothermal Energy Association (GEA) is a trade association composed of U.S. companies who support the expanded use of geothermal energy and are developing geothermal resources worldwide for electrical power generation and direct-heat uses. Our members have offices or operations in many states and in numerous countries throughout the world. GEA advocates for public policies that will promote the development and utilization of geothermal resources, provides a forum for the industry to discuss issues and problems, encourages research and development to improve geothermal technologies, presents industry views to governmental organizations, provides assistance for the export of geothermal goods and services, compiles statistical data about the geothermal industry, and conducts education and outreach projects. Why Join GEA?: The Geothermal Energy Association is the definitive voice of the geothermal industry and works adamantly on your behalf to (1) support long-term industry growth through education, information, outreach and advocacy and (2) increase public awareness of geothermal energy and understanding of its near- and long- term potential. Membership dues provide the bulk of financial support for GEA and directly facilitate our efforts to engage policy makers on critical industry issues, organize events, produce geothermal industry data, reports, and publications, engage the press in an aggressive public relations effort, publish the most widely-circulated geothermal newsletter, and more. We provide our members with the most up-to-date information on what is going on in the geothermal industry today and the factors that are shaping the industry for tomorrow. GEA’s role has never been more vital and your participation is critical as we endeavor to expand the use of this clean, renewable, sustainable energy source and continue our work advocating for the industry. GEA membership offers a range of material benefits as well, including listing in GEA’s member database with a link to your company Web site, discounts on all event registrations, a special exhibit fee at the GEA Geothermal Energy Expo, and access to exclusive members-only meetings and workshops. www.geo-energy.org Geothermal Basics: Q&A © 2012 Geothermal Energy Association Acknowledgments The Geothermal Energy Association (GEA) acknowledges all those who have contributed to this report. Special thanks to Tonya (Toni) Boyd (Oregon Institute of Technology), William Glassley (University of California, Davis), Elizabeth Littlefield (University of Nevada, Reno), and Joel Renner for reviewing the content herein. Continuing thanks is also due to those who provided valuable input to a 2009 version of this document: Dan Fleischmann (Ormat Technologies), Roy Mink, Marilyn Nemzer (Geothermal Education Office), John Pritchett (Science Applications International Corporation), and Jeff Tester and his then-graduate students at Massachusetts Institute of Technology. Previous GEA reports and other GEA resources make up a large bulk of this content. Principal authors of those reports include: Diana Bates, Leslie Blodgett, Karl Gawell, Nathanael Hance, Alison Holm, Daniel Jennejohn, Alyssa Kagel, and Mark Taylor. Collectively, GEA’s past reports, available at www.geo-energy.org, have benefitted from input by scores of individuals in the geothermal community; despite being unable to provide an exhaustive list, we wish to thank all those individuals. Cover photo sources: Terra-Gen (Coso), Calpine Corp. (The Geysers), Ormat (Puna), Enel Green Power (Stillwater) Geothermal Basics: Q&A Table of Contents ACKNOWLEDGMENTS ................................................................................. 1 TABLE OF CONTENTS ................................................................................... 2 1. TECHNOLOGY BASICS............................................................................... 5 1.1. What is geothermal energy? ....................................................... 5 FIGURE 1: TEMPERATURES IN THE EARTH ............................................................... 5 FIGURE 2: GEOTHERMAL RESERVOIR ..................................................................... 6 FIGURE 3: FIRST GEOTHERMAL PLANT, 1904, LARDERELLO, ITALY .............................. 7 1.2. What is a baseload resource? ........................................................... 8 1.3. How does a conventional geothermal power plant work? ................ 9 FIGURE 4: TOTAL U.S. GEOTHERMAL INSTALLED CAPACITY BY TECHNOLOGY (MW) 1975–2012 .................................................................................................... 9 FIGURE 5: FLASH POWER PLANT ........................................................................ 10 FIGURE 6: DRY STEAM POWER PLANT ................................................................. 11 FIGURE 7: BINARY POWER PLANT ....................................................................... 12 FIGURE 8: FLASH/BINARY POWER PLANT ............................................................. 13 1.4. How do geothermal heat pumps work? .......................................... 13 FIGURE 9: GEOTHERMAL HEAT PUMPS ................................................................ 14 1.5. How do direct use applications work? ............................................. 15 FIGURE 10: DIRECT USE GEOTHERMAL HEATING SYSTEM ....................................... 16 2. CURRENT USE ........................................................................................ 17 2.1. How much geothermal energy is used in the U.S.? ......................... 17 2.2. What non-conventional technologies are used for geothermal production? ............................................................................................ 18 FIGURE 11: CALIFORNIA RENEWABLE ENERGY GENERATION BY FUEL TYPE, 1983-2010 .................................................................................................................... 19 2.3. How much geothermal energy is used internationally? .................. 20 TABLE 1. COUNTRIES GENERATING GEOTHERMAL POWER AS OF MAY 2012 .............. 21 FIGURE 12: TOP COUNTRIES FOR GEOTHERMAL CAPACITY GROWTH, 2008-2012 ...... 22 3. POTENTIAL USE ...................................................................................... 24 2 Table of Contents 3.1. What is the potential of using geothermal resources in the U.S.? .. 24 TABLE 2. GEOTHERMAL RESOURCE POTENTIAL IN WESTERN STATES ......................... 25 FIGURE 13: UNITED STATES HEAT FLOW MAP ...................................................... 26 3.2. What technologies will expand geothermal energy uses in the short term? ...................................................................................................... 27 TABLE 3. DOE-FUNDED EGS DEMONSTRATION PROJECTS ...................................... 29 FIGURE 14: SMU ESTIMATED CO-PRODUCED GEOTHERMAL POTENTIAL ................... 31 FIGURE 15: GEOPRESSURED BASINS IN THE UNITED STATES ..................................... 32 3.3. What is the international potential of geothermal energy? ........... 34 TABLE 4. WORLD CONTINENTAL GEOTHERMAL RESOURCES ..................................... 34 4. SUPPORTING POLICIES ........................................................................... 35 4.1. Are U.S. laws driving new growth in geothermal development today? .................................................................................................... 35 4.2. What laws govern geothermal energy on U.S. public lands? .......... 36 4.3. What state laws govern geothermal energy in the U.S.? ................ 37 5. ENVIRONMENTAL BENEFITS .................................................................. 38 5.1. How effectively does geothermal help in improving air quality and decreasing greenhouse gas emissions? .................................................. 39 FIGURE 16. COMPARISON OF COAL, NATURAL GAS, AND GEOTHERMAL CO2 EMISSIONS .................................................................................................................... 39 5.2. How much land does geothermal energy use? ............................... 41 FIGURE 17. TYPICAL DISTURBANCES BY PHASE OF GEOTHERMAL RESOURCE DEVELOPMENT ................................................................................................ 42 5.3. How noisy are geothermal plants? .................................................. 43 5.4. How do geothermal developers use water? .................................... 44 5.5. Does seismic activity affect geothermal applications (and vice versa)? .................................................................................................... 46 FIGURE 18. AGGREGATED WATER CONSUMPTION FOR ELECTRIC POWER GENERATION, LIFETIME ENERGY OUTPUT ................................................................................ 47 6. ECONOMIC BENEFITS ............................................................................. 48 6.1. How does geothermal energy benefit the U.S. economy? .............. 48 3 Geothermal Basics: Q&A 6.2. Is geothermal market investment growing? ................................... 49 TABLE 5. NEAR-TERM GEOTHERMAL POTENTIAL & RESULTING ECONOMIC CONTRIBUTION ............................................................................................... 51 6.3. How does geothermal energy benefit local economies? ................. 51 6.4. How does geothermal energy benefit developing countries? ......... 53 7. POWER PLANT
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