GeothermalAlternative Energy for the Future?

Geo what?Geothermal!

from the Greek roots geo, meaning earth, and thermos, meaning heat

thermal energy (heat) stored in Earth

geothermal gradient of temperatures through the crust is 25–30 °C per kilometer of depth

four main layers

heat of the Earth radiates outward

mantle melts at 300° F- 700°F

Is it done yet?The Earth hasn't cooled yet

The center is extremely hot (6000 C) due to a combination of radioactivity and residual heat from the formation of the Earth

melted mantle makes molten magma…

magma reaches surface of crust and is called lava

magma reaches crust and heats nearby rocks and water

heated water can reach the surface and form hot springs

So, how does it work?Geothermal Gradient

The difference in temperature between the core of the planet and its surface

Continuous exchange of thermal energy from core to surface

Yeah, but how?Geothermal energy is produced by drilling a well into the ground where thermal activity is

occurring

Once a well has been identified and a well head attached, the steam is separated from the water, the water is diverted through a turbine engine which turns a generator

The water is injected back into the ground to resupply the geothermal source

The Bad News First:Direct geothermal heating systems contain

pumps and compressors, which consume energy

Construction of plants can affect land stability

Professional installation: $25,000

Contrary to Native Worldview

Then the Good News:Recycling the Earth’s energy

No heating bill (but small electricity cost)

One time investment

Geothermal energy is clean, no fuel is burned and therefore no by product present

Native Worldview: A Case from Hawaii

Conflict Opposing views of environment

Native opposition to geothermal energy development

Native Hawaiians protested against geothermal development

Wao Kele O Puna rainforest development

Summary:Geothermal energy uses the Earth’s thermal

gradient for heat and power

“Green” energy with few byproducts

Expensive

Contrary to native worldview

Personal preference

Questions?

Thank you for your attention!

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

http://www.helium.com/items/324657-what-causes-a-volcano-to-erupt

http://academic.evergreen.edu/g/grossmaz/heidtken.html

http://climateprogress.org/2007/09/07/geothermal-an-underrated-climate-solution/

http://www.odec.ca/projects/2007/truo7j2/geo.htm

http://www.txucorp.com/responsibility/education/generation/geothermal.aspx

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

http://www.canada.com/reginaleaderpost/news/business_agriculture/story.html?id=f7f67b8f-42e2-4105-ad10-bc4cd1d72cfa

http://www.culturalsurvival.org/ourpublications/csq/article/hawaiis-rainforest-crunch-land-people-and-geothermal-development

http://www.informaworld.com/smpp/content~db=all~content=a905843913

http://www.eia.doe.gov/cneaf/solar.renewables/page/geothermal/geothermal.html