The Environmental Benefits of Geothermal Energy

1. The Environmental Benefits of Geothermal Energy

2. Benefits of Geothermal Power • Renewable and Sustainable • Generates Continuous, Reliable “Baseload” Power • Conserves Fossil Fuels and Contributes to Diversity in Energy Sources • Clean and Safe Energy – Uses Less Land Than Other Sources of Energy including renewables • Produces low to zero air emissions • Preserves freshwater supply • Enhances National Security by Reducing Dependence on Imported Fuels

3. Why Geothermal is Renewable

4. Geothermal Potential 3 kilometer depth (1.9 miles)

5. Geothermal Potential at 6 kilometer (3.8 mile) depth Source: US DOE

6. Capacity Factor Comparison Non-Combustion Renewable Energy 92% 32% 25%

7. Total Domestic Energy Use, 2003 Source: Renewable Energy Trends 2003, DOE. http://www.eia.doe.gov/cneaf/solar.renewables/page/trends/fig1.html.

8. 30 Year Land Use

9. Air Emissions Power Generation contributes: • 23% of national nitrogen oxide emissions. • 67% of national sulfur dioxide emissions. • 40% of man-made carbon dioxide emissions. • Source: U.S. EPA • Source: U.S. EPA

10. Effects of Air Emissions • Health Impacts • Water Quality Deterioration • Acid Rain • Global Warming

11. Coal reported as average existing system emissions, natural gas reported as average existing steam cycle, simple gas turbine, and combined cycle system emissions, from Platts Researching and Consulting, based on data from the EPA’s Continuous Emissions Monitoring Program, 20003. Average emissions rates in the United States from oil-fired generation from EPA Clean Energy Impacts (2005). Geothermal information from US DOE, 2000.

12. Sources: Natural gas, coal, and geothermal data from: Platts Researching and Consulting, based on data from the EPA’s Continuous Emissions Monitoring Program, 2003. Coal figure represent the average existing coal plant, natural gas figure includes the average existing steam cycle, simple gas turbine, and combined cycle natural gas plant; Average emissions rates in the United States from oil-fired generation from EPA Clean Energy Impacts (2005).

13. Source: Average emissions rates in the United States from oil-fired generation from EPA Clean Energy Impacts (2005); coal and natural gas: Platt’s Research and Consulting, based on data from EPA’s Continuous Monitoring System (2003); geothermal: DOE data (2000).

14. Geothermal versus Coal • 10,837 times more sulfur dioxide, • 3,865 times more nitrous oxide, • and 23 times more carbon dioxide per megawatt hour than a geothermal plant Source: Coal data from Cherokee plant (Colorado) provided by Xcel Energy; Geothermal from the average of 11 Sonoma County steam power plants at The Geysers provided by Calpine Corporation as submitted to the Northern Sonoma County Air Pollution Control District for 2003 emissions inventory.

15. Source, geothermal: Telephone Flat Environmental Impact Statement 3.2-32, 3.2-34, 3.2-35; natural gas: Calpine Corporation Sutter Power Plant Project, Application for Certification (AFC) (Dec 1997). Table 2.2-1, Estimated Average Daily Water Requirements.

16. KEYS TO SUSTAINABILITY • Improve Energy Conversion Efficiency • Drill for New Steam • Recharge the Reservoir • Reduce Operating Costs

18. Sonoma Overlook