EPIBuilding a Sustainable Future
Lester R. Brown

Chapter 5. Stabilizing Climate: Shifting to Renewable Energy: Energy from the Earth

The heat in the upper six miles of the earth’s crust contains 50,000 times as much energy as found in all the world’s oil and gas reserves combined—a startling statistic that few people are aware of. Despite this abundance, only 10,500 megawatts of geo¬thermal generating capacity have been harnessed worldwide. 64

Partly because of the dominance of the oil, gas, and coal industries, which have been providing cheap fuel by omitting the costs of climate change and air pollution from fuel prices, relatively little has been invested in developing the earth’s geothermal heat resources. Over the last decade, geothermal energy has been growing at scarcely 3 percent a year. 65

Half the world’s existing generating capacity is in the United States and the Philippines. Mexico, Indonesia, Italy, and Japan account for most of the remainder. Altogether some 24 countries now convert geothermal energy into electricity. Iceland, the Philippines, and El Salvador respectively get 27, 26, and 23 percent of their electricity from geothermal power plants. 66

The potential of geothermal energy to provide electricity, to heat homes, and to supply process heat for industry is vast. Among the countries rich in geothermal energy are those bordering the Pacific in the so-called Ring of Fire, including Chile, Peru, Colombia, Mexico, the United States, Canada, Russia, China, Japan, the Philippines, Indonesia, and Australia. Other geothermally rich countries include those along the Great Rift Valley of Africa, such as Kenya and Ethiopia, and those around the Eastern Mediterranean. 67

Beyond geothermal electrical generation, an estimated 100,000 thermal megawatts of geothermal energy are used directly—without conversion into electricity—to heat homes and greenhouses and as process heat in industry. This includes, for example, the energy used in hot baths in Japan and to heat homes in Iceland and greenhouses in Russia.68

An interdisciplinary team of 13 scientists and engineers assembled by the Massachusetts Institute of Technology (MIT) in 2006 assessed U.S. geothermal electrical generating potential. Drawing on the latest technologies, including those used by oil and gas companies in drilling and in enhanced oil recovery, the team estimated that enhanced geothermal systems could be used to massively develop geothermal energy. This technology involves drilling down to the hot rock layer, fracturing the rock and pumping water into the cracked rock, then extracting the superheated water to drive a steam turbine. The MIT team notes that with this technology the United States has enough geothermal energy to meet its energy needs 2,000 times over. 69

Though it is still costly, this technology can be used almost anywhere to convert geothermal heat into electricity. Australia is currently the leader in developing pilot plants using this technology, followed by Germany and France. To fully realize this potential for the United States, the MIT team estimated that the government would need to invest $1 billion in geothermal research and development in the years immediately ahead, roughly the cost of one coal-fired power plant. 70

Even before this exciting new technology is widely deployed, investors are moving ahead with existing technologies. For many years, U.S. geothermal energy was confined largely to the Geysers project north of San Francisco, easily the world’s largest geothermal generating complex, with 850 megawatts of generating capacity. Now the United States, which has more than 3,000 megawatts of geothermal generation, is experiencing a geothermal renaissance. Some 126 power plants under development in 12 states are expected to nearly triple U.S. geothermal generating capacity. With California, Nevada, Oregon, Idaho, and Utah leading the way, and with many new companies in the field, the stage is set for massive U.S. geothermal development. 71

Indonesia, richly endowed with geothermal energy, stole the spotlight in 2008 when it announced a plan to develop 6,900 megawatts of geothermal generating capacity. The Philippines, currently the world’s number two generator of electricity from geothermal sources, is planning a number of new projects. 72

Among the Great Rift countries in Africa—including Tanzania, Kenya, Uganda, Eritrea, Ethiopia, and Djibouti—Kenya is the early leader. It now has over 100 megawatts of geothermal generating capacity and is planning 1,200 more megawatts by 2015. This would double its current electrical generating capacity of 1,200 megawatts from all sources. 73

Japan, which has 18 geothermal power plants with a total of 535 megawatts of generating capacity, was an early leader in this field. Now, following nearly two decades of inactivity, this geo¬thermally rich country—long known for its thousands of hot baths—is again beginning to build geothermal power plants. 74

In Europe, Germany has 4 small geothermal power plants in operation and some 180 plants in the pipeline. Werner Bussmann, head of the German Geothermal Association, says, “Geothermal sources could supply Germany’s electricity needs 600 times over.” Monique Barbut, head of the Global Environment Facility, expects the number of countries tapping geothermal energy for electricity to rise from roughly 20 when the century began to close to 50 by 2010. 75

 Beyond geothermal power plants, geothermal (ground source) heat pumps are now being widely used for both heating and cooling. These take advantage of the remarkable stability of the earth’s temperature near the surface and then use that as a source of heat in the winter when the air temperature is low and a source of cooling in the summer when the temperature is high. The great attraction of this technology is that it can provide both heating and cooling and do so with 25–50 percent less electricity than would be needed with conventional systems. In Germany, for example, there are now 130,000 geothermal heat pumps operating in residential or commercial buildings. This base is growing steadily, as at least 25,000 new pumps are installed each year. 76

In the direct use of geothermal heat, Iceland and France are among the leaders. Iceland’s use of geothermal energy to heat almost 90 percent of its homes has largely eliminated coal for this use. Geothermal energy accounts for more than one third of Iceland’s total energy use. Following the two oil price hikes in the 1970s, some 70 geothermal heating facilities were constructed in France, providing both heat and hot water for an estimated 200,000 residences. In the United States, individual homes are supplied directly with geothermal heat in Reno, Nevada, and in Klamath Falls, Oregon. Other countries that have extensive geothermally based district-heating systems include China, Japan, and Turkey. 77

Geothermal heat is ideal for greenhouses in northern countries. Russia, Hungary, Iceland, and the United States are among the many countries that use it to produce fresh vegetables in the winter. With rising oil prices boosting fresh produce transport costs, this practice will likely become far more common in the years ahead. 78

Among the 16 countries using geothermal energy for aquaculture are China, Israel, and the United States. In California, for example, 15 fish farms annually produce some 10 million pounds of tilapia, striped bass, and catfish using warm water from underground. 79

The number of countries turning to geothermal energy for both electricity and heat is rising fast. So, too, is the range of uses. Romania, for instance, uses geothermal energy for district heating, for greenhouses, and to supply hot water for homes and factories. 80

Hot underground water is widely used for both bathing and swimming. Japan has 2,800 spas, 5,500 public bathhouses, and 15,600 hotels and inns that use geothermal hot water. Iceland uses geothermal energy to heat some 100 public swimming pools, most of them year-round open-air pools. Hungary heats 1,200 swimming pools with geothermal energy. 81

If the four most populous countries located on the Pacific Ring of Fire—the United States, Japan, China, and Indonesia—were to seriously invest in developing their geothermal resources, they could easily make this a leading world energy source. With a conservatively estimated potential in the United States and Japan alone of 240,000 megawatts of generation, it is easy to envisage a world with thousands of geothermal power plants generating some 200,000 megawatts of electricity, the Plan B goal, by 2020. 82

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64. Karl Gawell et al., International Geothermal Development Directory and Resource Guide (Washington, DC: Geothermal Energy Association (GEA), 2003); EER, Global Geothermal Markets and Strategies 2009–2020 (Cambridge, MA: May 2009).

65. Geothermal growth rate calculated using Ruggero Bertani, “World Geo¬thermal Generation in 2007,” GHC Bulletin, September 2007, pp. 8–9, and EER, op. cit. note 64.

66. Bertani, op. cit. note 65, pp. 8–9; Kara Slack, U.S. Geothermal Power Production and Development Update (Washington, DC: GEA, March 2009); EER, op. cit. note 64; number of countries with geothermal power from Karl Gawell et al., 2007 Interim Report: Update on World Geothermal Development (Washington, DC: GEA, 1 May 2007), p. 1; share of electricity calculated using installed capacity from Bertani, op. cit. note 65, p. 9; capacity factor from Ingvar B. Fridleifsson et al., “The Possible Role and Contribution of Geothermal Energy to the Mitigation of Climate Change,” in O. Hohmeyer and T. Trittin, eds., IPCC Scoping Meeting on Renewable Energy Sources, Proceedings (Luebeck, Germany: 20–25 January 2008), p. 5, and from “World Total Net Electricity Generation, 1980–2005,” in DOE, EIA, “International Energy Annual 2005—World Electricity Data,” at www.eia.doe.gov/iea/elec.html, updated 13 September 2007.

67. World Bank, “Geothermal Energy,” prepared under the PB Power and World Bank partnership program, www.worldbank.org, viewed 23 January 2003.

68. Jefferson Tester et al., The Future of Geothermal Energy: Impact of Enhanced Geothermal Systems (EGS) on the United States in the 21st Century (Cambridge, MA: Massachusetts Institute of Technology, 2006); John W. Lund and Derek H. Freeston, “World-Wide Direct Uses of Geothermal Energy 2000,” Geothermics, vol. 30 (2001), pp. 34, 46, 51, 53.

69. Tester et al., op. cit. note 68, pp. 1–4; Julian Smith, “Renewable Energy: Power Beneath Our Feet,” New Scientist, 8 October 2008.

70. Rachel Nowak, “Who Needs Coal When You Can Mine Earth’s Deep Heat?” New Scientist, 19 July 2008; Tester et al., op. cit. note 68.

71. UCS, “How Geothermal Energy Works,” at www.ucsusa.org/clean_energy/renewable_energy_basics/offmen-how-geothermal-energy-works.html, viewed 22 April 2009; Slack, op. cit. note 66.

72. “Geothermal Power Projects to Cost $US19.8 Bln, Official Says,” op. cit. note 6; Ed Davies and Karen Lema, “Geothermal-Rich SE Asia Struggles to Tap Earth’s Power,” Reuters, 30 June 2008; Bertani, op. cit. note 65, pp. 8–9; “Energy Dev Corp.: Bid to Become Top Geothermal Producer,” Agence France-Presse, 14 January 2009; Geysir Green Energy, “Philippines,” at www.geysirgreenenergy.com/Operations-and-Development/asia/philippines, viewed 22 April 2009.

73. German Federal Institute for Geosciences and Natural Resources (BGR), “African Rift Geothermal Facility (ARGeo),” at www.bgr.de/geotherm/projects/argeo.html, viewed 22 April 2009; U.N. Environment Programme (UNEP), “Hot Prospect—Geothermal Electricity Set for Rift Valley Lift-Off in 2009,” press release (Nairobi: 9 December 2008); Bertani, op. cit. note 65, pp. 8–9; DOE, op. cit. note 3.

74. Yoko Nishikawa, “Japan Geothermal Projects Pick Up After 20 Years: Report,” Reuters, 4 January 2009; Bertani, op. cit. note 65, pp. 8–9; Lund and Freeston, op. cit. note 68, p. 46.

75. Werner Bussmann, “Germany: The Geothermal Market is Expanding,” presentation to the Renewable Energy Exhibition, Lyon, Paris, 25–28 February 2009; Jane Burgermeister, “Geothermal Electricity Booming in Germany,” Renewable Energy World, 2 June 2008; UNEP, op. cit. note 73.

76. DOE, EERE, “Energy Savers: Geothermal Heat Pumps,” updated 24 February 2009, and “Energy Savers: Benefits of Geothermal Heat Pump Systems,” updated 30 December 2008, both at www.energysavers.gov; Burgermeister, op. cit. note 75.

77. Iceland National Energy Authority and Ministries of Industry and Commerce, Geothermal Development and Research in Iceland (Reykjavik, Iceland: April 2006), p. 16; World Bank, op. cit. note 67.

78. Lund and Freeston, op. cit. note 68, pp. 34, 51, 53.

79. World Bank, op. cit. note 67.

80. Ibid.

81. Lund and Freeston, op. cit. note 68, pp. 46, 53.

82. United States from Tester et al., op. cit. note 68; Japan based on assumption that Enhanced Geothermal Systems could double 72,000 MW potential, from Hirofumi Muraoka et al., “Assessment of Hydrothermal Resource Potentials in Japan 2008,” Abstract of Annual Meeting of Geo¬thermal Research Society of Japan (Kanazawa, Japan: 2008); Hirofumi Muraoka, National Institute of Advanced Industrial Science and Technology, e-mail to J. Matthew Roney, Earth Policy Institute, 13 July 2009.

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