TitleGeothermal Industry Grows, With Help From Oil and Gas Drilling
BodyGeothermal energy — tapping into heat deep underground and using it to produce power — is sometimes described as a forgotten renewable. It languishes in the shadows of better-known sources like wind and the sun, and in 2011 it accounted for less than 1 percent of electric power worldwide, according to last year’s World Energy Outlook. Yet the geothermal industry is growing, if slowly, and proponents hope that new technologies — including tie-ins with drilling for oil and natural gas — will bring further gains. Last year, the amount of electric power capacity available from geothermal resources grew about 4 percent to 5 percent globally, according to a report released in April by the Geothermal Energy Association, which is based in Washington. The United States remains the world’s leader in the use of geothermal energy for electric power, followed by the Philippines, Indonesia and Mexico, according to the report. Large projects are planned for Indonesia and East Africa, and some Central and South American countries, such as Chile, are also showing interest. These fast-growing regions are hungry for new electricity sources, and international development banks are helping to finance the projects. (The lower-population New Zealand and Iceland are ranked sixth and seventh in total geothermal use.) “If you’re wildcatting for geothermal, Africa really is one of those parts of the world where we seem to be going to,” said Maria Richards, coordinator of the geothermal laboratory at Southern Methodist University in Dallas. At its most basic, geothermal power involves harnessing water heated to steam temperatures in the depths of the earth and using it to spin turbines that produce electricity. The Ring of Fire around the Pacific Ocean, where volcanoes and earthquakes are common, is an optimal source of energy, with high temperatures found relatively close to the surface. In addition to producing electric power, geothermal can also heat and cool homes, an application that can use lower temperatures than electric power production. As an electricity source, geothermal energy has certain advantages over its main renewable competitors, the sun and wind. It works 24 hours a day, while solar and wind power are intermittent. Geothermal energy generates few planet-warming emissions, and it provides an alternative to hydroelectric power for countries like Kenya and El Salvador that might want to reduce their dependence on dams, said Eckehard Büscher, director of the International Geothermal Office in Germany. But geothermal has been slow to develop for several reasons. It carries substantial upfront costs. For instance, construction recently began on a huge geothermal plant in Indonesia, with the cost projected to reach $1.6 billion, according to Reuters. It is also hard to predict exactly where hot water will pool in the earth’s crust, which creates uncertainties about where to drill. “You can put out a meter and measure easily how much wind and solar is at a site,” Ms. Richards said. “You can get real data.” But it is “much harder to understand” how much geothermal hot water is available in a certain area. Continue reading the main story Continue reading the main story Continue reading the main story Drilling wells is expensive, taking 50 percent to 60 percent of a project’s total costs, according to Kewen Li, a senior research engineer at the Stanford University School of Earth Sciences. The wells go hundreds or thousands of feet down, and 10 percent to 30 percent of the test wells are unsuccessful, Dr. Büscher said. Also, corrosion and scaling may occur in deep wells, and drilling rigs — also used by oil and gas companies — may not always be available, he said. Yet more experience, emerging technology that can derive energy from lower temperatures and a new wave of interest in oil and gas drilling stand to aid geothermal. The spread of hydraulic fracturing, the water-intensive technique of extracting oil or gas from hard rock, has reduced energy prices, making renewable sources less attractive but at the same time shortening the learning curve for the geothermal industry. “There’s a lot more data accessible because of oil and gas,” said Ms. Richards, of Southern Methodist University. That includes information on temperatures and water availability in individual wells, as well as three-dimensional seismic data that is useful because, for example, hot fluid can travel along fault lines. This spring, the United States completed the National Geothermal Data System, with information partly contributed by the oil and gas industry. Some researchers, like Ms. Richards and Dr. Li, dream of using abandoned oil and gas wells — which have already been drilled, saving money — to produce small-scale geothermal power. A pilot project in the Huabei oil field not far from Beijing is doing just that, said Dr. Li, the research engineer at Stanford. China, eager to reduce its reliance on fuels that contribute to smog, is the largest global market for geothermal energy used to heat and cool buildings, according to Dr. Büscher of the International Geothermal Office. Other countries are using this technology as well: In Germany, the city of Munich, for example, aims to obtain all its heating from renewables by 2025, and this will mostly be geothermal, Dr. Büscher said. For many places not blessed (or cursed) with heat from the Ring of Fire, this application of geothermal — requiring lower temperatures than what are needed for electric power — is likely to develop more quickly.
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