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1. Geothermal
Alternative Energy for the Future?

2. 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

3. four main layers
heat of the Earth radiates outward
mantle melts at 300° F- 700°F

4. 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…

5. 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

6. 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

7. 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

8. 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

9. 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

10. 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

11. 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!

12. 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