Geothermal Energy

Blake Crowe
November 22, 2012

Submitted as coursework for PH240, Stanford University, Fall 2012


Fig. 1: A cross section of the Earth Source: Wikimedia Commons

Geothermal energy has proven to be cheaper to install and cheaper to produce energy per kilowatt-hour then any other type of renewable energy. [1] The benefits over other renewable are obvious. The energy that exists in the earth is not depended on weather or nearly as many factors as solar, hydro, and wind energy technologies are. Iceland is the case study drawing 49% of its energy from geothermal energy while using only "8% of the geothermal potential." [1,2] California is also an impressive geothermal producer with almost 12740 GWh produce in 2010. [3] With costs at 2 cents per Kilowatt-hour in some of hottest regions it is currently the cheapest renewable energy to produce. [1,4] The use of geothermal energy in the United States is primarily in personal geothermal pumps used for space heating with a small amount used for electricity production. The requirements to produce electricity from geothermal sites are temperature in excess of 200 degrees Celsius and pressure in excess of 30 bars. [1] With all of this information it is clear that geothermal energy is something worth investing in. According to T. J. Hammonds the effective avenues of research include "Increased resources information, increased knowledge of potential uses," and other economic barriers. [1] While all of these may contribute to the problem the real issue with geothermal energy is the advertising and public perception.


In the last election green energy advertising carried a $152 million price tag, and McCain spent millions on advertisements supporting wind and solar. [5] Geothermal energy was tapped in the last election by Chevron but the focus of the advertisement is what really matters. [5] The advertisement is only concerned with the people and the technologies surrounding geothermal energy. With the cost of drilling a 2000-meter hole costing only $1 million what are they buying with all of this add space? [1] It appears obvious, the green energy sector is still supported by the government and with an unhelpful President they have their business lives at stake. Struggling companies are paying millions to get the message to you that the answer is in technologies but in reality the energy that they are producing are not competitive with coal and oil. The cost per kilowatt is more and the cost of installation is higher yet we still spend millions. [6] Geothermal should be brought up to a similar level of pubic attention,


The use of geothermal energy is not new with the use of hot springs dating back to 11,000 BCE. [4] These dependable energy sources have been in use continually in bathing and healing through out our history. We now exploit these energy sources for heating, fish farming and in rare cases electricity. [6] Geology has lead to a better understanding of the deposits of geothermal energy. As geology progress the technologies to measure and capacity to understand what is going on miles below the earth improve. [7] The existence and explicit knowledge of the tectonic plates might as well be a treasure map of where to find trapped energy in the crust. As information becomes more readily available and geothermal plants continue to make a large dent in the carbon industry.


Geothermal energy is in a unique position as it can only be seen in rare cases such as Yellowstone and when it is it is more of a novelty then a serious display of energy, or a volcano/earthquake that produces a massive explosion of energy. According to the Department of Energy (DOE) The Geysers, a geothermal plant in northwest California, wastewater is pumped in from nearby cities in the amount of millions of gallons a day. The plant takes the wastewater and depending on the plant, turns it to steam, which eventually spin a turbine. This plant produces 725 MW of power with minimal carbon output. [8] The problem here is the lack of pubic knowledge. Solar, wind and hydropower technologies are well understood by the public because both they are visually understandable with little to no science. Geothermal energy relies on some less intuitive ideas. The value of geothermal energy lies in the consistency of the temperature change as you travel downward. The steady increase in temperature as you travel downward makes it available to all landowners. The ignorance of the general public lead to solar and wind technologies becoming the face of clean energy. Unfortunately for the green energy sector these are, expensive to produce, expensive to develop, and space intensive. These are the projects that get the funding and public exposure because they are the ones building next to the freeway and on roofs. Geothermal runs into problems when it comes to location of energy production and its transmission of that power to the customer. Unfortunately other green technologies suffer from similar problems. In fact, if the water is transported instead of the electricity it is possible to see a temperature change of around 1 degree C over a 10km well insulated pipe.

© Blake Crowe. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.


[1] T. J. Hammons, "Geothermal Power Generation: Global Perspectives; USA and Iceland; Technology, Direct Uses, Plants, and Drilling," Int. J. Power Energy Sys. 27, No. 2, 157 (2007).

[2] J. W. Lund and D. H. Freeston, "World-Wide Direct Uses of Geothermal Energy 2000," Geothermics 30, 29 (2001).

[3] D. Jennejohn et al., "Energizing Southern California's Economy: The Economic Benefits and Potential for Geothermal Energy in Southern California," Geothermal Energy Association, October 2011.

[4] I. B. Fridleifsson, "Geothermal Energy For the Benefit of the People," Renew. Sustain. Energy Rev. 5, 299 (2001).

[5] E. Lipton and C. Krauss, "Fossil Fuel Industry Ads Dominate TV Campaign," New York Times, 13 Sep 12.

[6] I. B. Fridleifsson, "Status of Geothermal Energy Amongst the World's Energy Sources," Geothermics 32, 379 (2003).

[7] M. H. Dickson and M. Fanelli, Geothermal Energy (Routledge, 2005).

[8] E. Douglass, "Calpine to Pump up Its Geothermal Power Source" Los Angeles Times, 31 May 07.