Geothermal Energy PDF
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This presentation details geothermal energy, explaining its sources, generation methods (dry steam and flash steam plants), and the world's largest geothermal power plant, the Geysers Geothermal Complex. It also covers the potential environmental effects of geothermal energy, like brine salinization and land subsidence. The document is a good starting point for learning about geothermal energy, and likely to be used as a supplementary tool in an education setting, possibly for college level courses or related training sessions.
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Geothermal Energy Sources of Earth’s Internal Energy 70% comes from the decay of radioactive nuclei with long half lives that are embedded within the Earth Some energy is from residual heat left over from Earths formation. The rest of the energy comes from meteorite impacts. Ge...
Geothermal Energy Sources of Earth’s Internal Energy 70% comes from the decay of radioactive nuclei with long half lives that are embedded within the Earth Some energy is from residual heat left over from Earths formation. The rest of the energy comes from meteorite impacts. Generation of Electricity is appropriate for sources >150oC Dry Steam Plants: use hydrothermal fluids that are already mostly steam, which is a relatively rare natural occurrence Flash Steam Plants: These are the most common plants. These systems pull deep, high pressured hot water that reaches temperatures of 3600F or more to the surface. This water is transported to low pressure chambers, and the resulting steam drives the turbines. The remaining water and steam are then injected back into the source from which they were taken. Geysers Geothermal Complex The largest geothermal plant in the world is called the Geysers Geothermal Complex, located in the United States, with a capacity of 900 megawatts. It is made up of 22 power plants and spread over several kilometers, located north of San Francisco. It sits on top of a deep magma chamber that spans over 30 square miles. Malitbog Geothermal Power Plant The Tongonan Geothermal Power Station is a 232.5 MW geothermal power plant or an earth steam turbined electric generator —the world's largest geothermal power plant under one roof located in Tongonan, Kananga, Leyte, Philippines. Binary Cycle This system passes moderately hot Plants: geothermal water past a liquid, usually an organic fluid, that has a lower boiling point. The resulting steam from the organic liquid drives the turbines. This process does not produce any emissions, and the water temperature needed for the water is lower than that needed in the Flash Steam Plants (2500F – 3600F). Casa Diablo Geothermal’s Harmful Effects Brine can salinate soil if the water is not injected back into the reserve after the heat is extracted. Extracting large amounts of water can cause land subsidence, and this can lead to an increase in seismic activity. To prevented this the cooled water must be injected back into the reserve in order to keep the water pressure constant underground. Power plants that do not inject the cooled water back into the ground can release H2S, the “rotten eggs” gas. This gas can cause problems if large quantities escape because inhaling too much is fatal.
