Geothermal energy is a renewable energy resource, which is based on using the heat under the Earth's surface. http://www.cangea.ca/what-is-geothermal/ While there are different methods of using this heat, the basis lies in using hot water reserves, which are found up to 10,000 feet underground, to generate steam, which then in turn spins turbines to produce electricity. http://www.powerscorecard.org/tech_detail.cfm?resource_id=3 This is achieved through drilling a pipe underground and tapping into the reserve.

Geothermal energy accounts for about 0.4 percent of total energy consumption in the US, and 0.4 percent of the entire world. While these numbers seem minuscule, it is important to remember that geothermal energy is quite a new source of power, and has very far to go to reach its full potential.

• Produces very little greenhouse gases or pollutants, unlike traditional fossil fuel sources
• Geothermal power plants take up very little space
• No significant impact on environment http://www.eia.doe.gov/kids/energyfacts/sources/renewable/geothermal.html
• Cheaper to maintain than other sources of power
• Comparable in cost to other sources of electricity generation http://www1.eere.energy.gov/geothermal/faqs.html
• Renewable and sustainable http://www.bbc.co.uk/schools/gcsebitesize/geography/energy/energydemandrev6.shtml
• Practically free
• Does not suffer from price fluctuations, like oil and gas
• Not affected by weather like solar power or wind power

• Inability to build a plant in most places around the world http://www.cangea.ca/what-is-geothermal/
• Availability of steam/water reserves at a low enough depth
• Stable rock foundation, which at the same time can be easily drilled through
• Possibility of running out of steam/water reserves http://home.clara.net/darvill/altenerg/geothermal.htm
• Risk of hazardous gases coming up from underground http://home.clara.net/darvill/altenerg/geothermal.htm

While geothermal energy is not a very significant source of power in today's world, it's importance in the future should not be underestimated. Future advances in drilling technology can allow people to build geothermal power plants in more places, as well as improve the efficiency of the entire process. http://www.cangea.ca/what-is-geothermal/ As fossil fuel reserves continue to run out, geothermal energy can play a major role as a replacement.