Plugging Into the Earth's Heat

Jonathan G. Dorn, Earth Policy Institute
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OneWorld.net note: In the first half of 2008, 24 countries worldwide were already harnessing heat from the Earth to generate enough electricity to sustain 60 million people -- roughly the population of the United Kingdom.

  • Cooling towers at the Geysers geothermal field, Harbin Springs, California. © kqedquest (flickr)Cooling towers at the Geysers geothermal field, Harbin Springs, California. © kqedquest (flickr)"Renewable energy is approaching a 'tipping point' and should expand dramatically in the next decade, further narrowing the gap between alternative forms of energy and fossil fuel use," said environmental and economic experts at a Washington, DC forum this June. In 2006, renewable energy sources accounted for 18 percent of global energy consumption, a figure that is surely on the rise as global investment in renewable energy grew by $30 billion between 2004 and 2007 alone, adds OneWorld.net's Jazmine Rodriguez, who reported from the event.

  • Solar power is one of various sources of renewable energy that has been getting greater attention around the globe. A large, U.S. utility company announced this month that it plans to invest in large-scale solar energy, a move that is expected to provide energy at a market rate for almost 250,000 houses a year and create about 1,000 jobs in California.

  • In tomorrow's OneWorld.net Daily Headlines [link | subscribe | RSS], Part II of this story will examine how developing countries like Kenya and Indonesia are starting to use geothermal energy.

World Geothermal Power Generation Nearing Eruption

From: Earth Policy Institute

Jonathan G. Dorn

August 19, 2008

With fossil fuel prices escalating and countries searching for ways to reduce oil dependence and greenhouse gas emissions, capturing the earth’s heat for power generation is garnering new attention. First begun in Larderello, Italy, in 1904, electricity generation using geothermal energy is now taking place in 24 countries, 5 of which use it to produce 15 percent or more of their total electricity. In the first half of 2008, total world installed geothermal power capacity passed 10,000 megawatts and now produces enough electricity to meet the needs of 60 million people, roughly the population of the United Kingdom. In 2010, capacity could increase to 13,500 megawatts across 46 countries—equivalent to 27 coal-fired power plants.

Originating from the earth’s core and from the decay of naturally occurring isotopes such as those of uranium, thorium, and potassium, the heat energy in the uppermost six miles of the planet’s crust is vast—50,000 times greater than the energy content of all oil and natural gas resources. Chile, Peru, Mexico, the United States, Canada, Russia, China, Japan, the Philippines, Indonesia, and other countries along the Ring of Fire (an area of high volcanic activity encircling the basin of the Pacific Ocean) are rich in geothermal energy. Another geothermal hot spot is the Great Rift Valley of Africa, which includes such countries as Kenya and Ethiopia. Worldwide, 39 countries with a cumulative population of over 750 million people have geothermal resources sufficient to meet all their electricity needs. (See data.)

Typically, power generation using the earth’s heat required underground pockets of high-temperature water or steam to drive a steam turbine. Now, new technologies that use liquids with low boiling points in closed-loop heat exchange systems allow electricity to be generated at much lower temperatures. This breakthrough is making geothermal power generation viable in countries such as Germany that are not known for their geothermal resources and is one reason why the number of countries using the earth’s heat to generate electricity could almost double by 2010.

One advantage of geothermal power plants, beyond the benefit of producing electricity from a low-carbon, indigenous energy source with no fuel costs, is that they provide baseload power 24 hours a day. Storage or backup-power is not required.

The United States leads the world in generating electricity from the earth’s heat. As of August 2008, geothermal capacity in the United States totaled nearly 2,960 megawatts across seven states—Alaska, California, Hawaii, Idaho, Nevada, New Mexico, and Utah. California, with 2,555 megawatts of installed capacity—more than any country in the world—produces almost 5 percent of its electricity from geothermal energy. Most of this capacity is installed in an area called the Geysers, a geologically active region north of San Francisco.

Thanks to the Energy Policy Act of 2005, which made geothermal power generation eligible to receive the federal renewable energy production tax credit, electricity generated from geothermal resources now costs the same as fossil-fuel-based electricity in many markets in the western United States. With favorable economics, the geothermal industry is experiencing a surge in activity. As of August 2008, some 97 confirmed new geothermal power projects with up to 4,000 megawatts of capacity were under development in 13 states, with some 550 megawatts of this already in the construction phase. Expected to create 7,000 permanent full-time jobs, the new capacity will include numerous large-scale projects such as the 350-megawatt and 245-megawatt projects by Vulcan Power near Salt Wells and Aurora, Nevada; the 155-megawatt project by CalEnergy near the Salton Sea in southern California; and the 120-megawatt project by Davenport Power near the Newberry Volcano in Oregon.

Current development is only scratching the surface of what is possible. The U.S. Department of Energy estimates that with emerging low-temperature technologies, at least 260,000 megawatts of U.S. geothermal resources could be developed. A study led by the Massachusetts Institute of Technology indicates that an investment of roughly $1 billion in geothermal research and development over 15 years (roughly the cost of a single new coal-fired power plant) could lead to commercial deployment of 100,000 megawatts by 2050.

In Europe, the top countries in geothermal energy development are Italy with 810 megawatts and Iceland with 420 megawatts. Italy is expected to nearly double its installed capacity by 2020. Iceland, with 27 percent of its electricity needs met by harnessing the earth’s heat, is number one in the world in the share of its electricity generated from geothermal energy. Germany, with only 8 megawatts of installed capacity, lags behind but is beginning to see the effects of a feed-in tariff of €0.15 (US $0.23) per kilowatt-hour that was implemented in 2004. Almost 150 plants are now in the pipeline in Germany, with most of the activity centered in Bavaria.

In tomorrow's OneWorld.net Daily Headlines [link | subscribe | RSS], Part II of this story will examine how developing countries like Kenya and Indonesia are starting to use geothermal energy.

To read more about geothermal power generation and other renewable energy sources, visit Earth Policy Institute.

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