Geothermal EnergyMichael R. BarrNational University

Geothermal Energy

Thermal energy generated and stored in the Earth 80% radioactive decay of minerals 20% original formation of the planet

First uses Paleolithic Age – hot springs bathing 3rd Century BC – oldest known spa 1st Century AD – public baths and under-floor

heating 14th Century – oldest district geothermal heating

system 1827 – earliest industrial exploitation

The Technology Behind Geothermal Energy

Electricity Generation Dry Steam Flash Steam - 360◦F or higher Binary Cycle – 225◦F to 360◦F

Enhanced Geothermal Systems (EGS)

Low Temperature or Co-Produced Resources

Heating and Cooling Agricultural Applications Direct Heating Heat Pumps

Current and Potential Usage

Electricity generating potential Estimates vary from 35 to 2,000 GW worldwide Doesn’t include non-electric heat recovered by

co-generation, geothermal heat pumps and other direct use.

Current worldwide installed capacity 10,900 MW (2011 est.)

2006 MIT Report | U.S. $1 Billion R&D investment over 15 years 100 GW electrical generating capacity by 2050.

Current and Potential Usage 2011 Earth Policy Institute Report

Geothermal source energy projected to double by 2015

Top 10 Geothermal Energy Locations (2010)

Rank Country Installed Capacity (MW)

National Energy Production (%)

1 United States 3,086 0.3

2 Philippines 1,904 27

3 Indonesia 1,197 3.7

4 Mexico 958 3

5 Italy 843 10

6 New Zealand 700 10

7 Iceland 575 30

8 Japan 536 0.3

9 El Salvador 204 14

10 Kenya 167 11.2

Source: Energy Digital (2012)

Leading Geothermal Energy Producers

Conclusions Geothermal energy…

Cost effective, cleaner, reliable, sustainable, and environmentally friendly.

Historically limited to tectonic plate boundaries. Technological advances open potential for widespread

exploitation. Geothermal Energy can help mitigate global warming if

widely deployed in place of fossil fuels. Resources theoretically more than adequate to supply

worldwide energy needs. Future forecasts depend on assumptions about

technology, energy prices, subsidies, and interest rates. Only a very small fraction can be sustainably exploited.

ReferencesEnergy Digital (2012). Top Ten: Geothermal Energy Locations.

Retrieved March 19, 2013 from http://www.energydigital.com/top_ten/top-10-business/top-ten-geothermal-energy-locations.

Geothermal Education Office (2005). Retrieved March 19,2013 from http://geothermal.marin.org/.

Massachusetts Institute of Technology (2006). The Future ofGeothermal Energy - Impact of Enhanced Geothermal Systems (EGS) on the United States in the 21st Century. Retrieved March 19, 2013 from http://geothermal.inel.gov/publications/future_of_geothermal_energy.pdf

National Renewable Energy Laboratory (2012). Retrieved March 19, 2013 from http://www.nrel.gov/learning/re_geo_elec_production.html

Roney, J. (2011). Geothermal Power Heating Up Worldwide.

Earth Policy Institute. Retrieved March 19, 2013 from http://www.earth-policy.org/plan_b_updates/2011/update98

Wikipedia (2013). Geothermal energy. Retrieved March 19,2013 from http://en.wikipedia.org/wiki/Geothermal_energy.