3-4. GEOTHERMAL ENERGY

3-4-1. Generals

• Thermal (heat) energy from the crust (un-derground or Earth)

• One of the renewable energies (others in-clude wind, solar, tidal, etc)

• Cost effective, reliable, sustainable, and environmentally friendly

• Mostly used for electricity generation

The Nesjavellir Geothermal Power Plant in Þingvellir, Iceland

http://en.wikipedia.org/wiki/Geothermal_energy

http://www.carbonneutral.com/carbon-offsets/geothermal-energy

3-4-2. Soureces

• Heat from the original formation energy (20%)

• Radioactive decay (80%)

3-4-3. World Production (of geothermal electricity)

Total of 10,959.7 MW in 2010

CountryCapacity (MW)

2007Capacity (MW)

2010% of national

electricity prod.% of global

geothermal prod.

United States 2687 3086 0.3 29

Philippines 1969.7 1904 27 18

Indonesia 992 1197 3.7 11

Mexico 953 958 3 9

Italy 810.5 843 1.5 8

New Zealand 471.6 628 10 6

Iceland 421.2 575 30 5

Japan 535.2 536 0.1 5

Iran 250 250

El Salvador 204.2 204 25

http://www.smartplanet.com/blog/smart-takes/geothermal-energy-potential-underutilized-report-says/

3-4-4. Environmental Effects

• Reduces greenhouse gases

• May release a small amount of green house gases & other toxic elements (CO2, H2S, CH4, NH3, Hg, As, B, Sb)

• Can affect the land stability (typically subsidence) and ecosystem near surface