the environmental benefits of geothermal energy. benefits of geothermal power renewable and...

The Environmental Benefits of Geothermal Energy

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

Why Geothermal is Renewable

Geothermal Potential 3 kilometer depth (1.9 miles)

Geothermal Potentialat 6 kilometer (3.8 mile) depth

Source: US DOE

Capacity Factor Comparison

Solar Wind Geothermal

25%32%

92%

Non-Combustion Renewable Energy

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

Total Domestic Energy Use, 2003

3642 3561

3237

1335

404

0

500

1000

1500

2000

2500

3000

3500

4000

sq meter / gigawatt-hour

Coal* Solar Thermal Photovoltaics Wind** Geothermal

power technology

30 Year Land Use

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. EPASource: U.S. EPA

Effects of Air Emissions

Health Impacts Water Quality Deterioration Acid Rain Global Warming

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

Nitrogen Oxide Comparison

Lbs/MWh 4.31 4 2.96 0

Coal Oil Natural Gas Geothermal

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.

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).

0

2

4

6

8

10

12

Sulfur Dioxide Comparison Equivalent

Lbs/MWh 10.39 10 0.22 0.35

Coal Oil Natural Gas Geothermal (Flash)

0

500

1000

1500

2000

2500

Carbon Dioxide Comparison

lbs/MWh 2191 1540 1212 60

Coal Oil Natural GasGeothermal

(flash)

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).

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.

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.

0

50

100

150

200

250

300

350

400

Average Operational Freshwater Use

gal/MW-hr 4.9 358

Geothermal Natural Gas

KEYS TO SUSTAINABILITY

Improve Energy Conversion Efficiency

Drill for New Steam

Recharge the Reservoir

Reduce Operating Costs

GEYSERS PRODUCTION AND INJECTION HISTORYCALPINE UNIT AREAS TOTAL

5,6

7,89,10

1112

13,14, 16 17

18Son

20WFFBC

Aid

0

50

100

150

200

250

1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003

BIL

LIO

N P

OU

ND

S

TOTAL PRODUCTION CONDENSATE CREEK SEGEP SRGRP

Cal

MASS REPLACEMENT FRACTION

020406080

100

1969 1971 1973 1975 1977 1979 1981 1983 1985 1987 1989 1991 1993 1995 1997 1999 2001 2003

%

SRGRPSEGEPCREEKCONDENSATE

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