Geothermal power

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Geothermal power

• Earths power harvested

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Geothermal power

• Geothermal power is energy generated by heat
  stored beneath the Earth's surface.
• The first geothermal generator was tested on 4
  July 1904, at the Larderello dry steam field in
  Italy.
• The largest group of geothermal power plants in
  the world is located in The Geysers, a geothermal
  field in California.
• As of 2007, geothermal power supplies less than
  1 of the world's energy.

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Contents

• 1 Electricity generation
• Dry Steam Power Plants
• Flash steam Power Plants
• Binary-cycle Power Plants
• 2 Geothermal energy usage
• 3 Advantages
• 4 Disadvantages

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Electricity generation

• There are three different types of power plants
• dry steam
• flash
• binary

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Dry Steam Power Plants

• A dry steam power plant uses dry steam .
• Dry steam is steam that contains no water
  droplets .
• Typically above 235C
• Dry steam plants are used where there is plenty
  of steam available that is not mixed with water.
• Dry steam plants are the simplest and most
  economical of geothermal plants.

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Flash steam Power Plants

• A Flash steam power plant uses hot water.
• Typically above 182 C
• The high pressure underground keeps the water in
  the liquid state, although it is well above the
  boiling point of water at normal sea level
  atmospheric pressure.
• As the water is pumped from the reservoir to the
  power plant, the drop in pressure causes the
  water to convert, or "flash", into steam to power
  the turbine.
• Flash steam plants are the most common type of
  geothermal power generation plants in operation
  today.

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Binary-cycle Power Plants

• The water used in binary-cycle power plants is
  cooler than that of flash steam plants.
• From 107 to 182 C
• The hot fluid from geothermal reservoirs is
  passed through a heat exchanger which transfers
  heat to a separate pipe containing fluids with a
  much lower boiling point (ios-butane or
  iso-pentane) which are vaporized to power the
  turbine .
• The advantage to binary-cycle power plants is
  their lower cost and increased efficiency.

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Geothermal energy usage

• Iceland
• The Svartsengi Power-Plant , The Nesjavellir
  Power-Plant, The Krafla Power-Plant
• United States
• there were 75 new geothermal power projects
  underway in 12 states as of May 2007 and are
  currently present in Alaska, California, Hawaii,
  Nevada, and Utah
• New Zealand
• Kawerau geothermal power station is a 90-megawatt
  geothermal power plant now under construction

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Advantages

• Its clean and safe for the surrounding
  environment.
• It is also sustainable because the hot water used
  in the geothermal process can be re-injected into
  the ground to produce more steam.
• From an economic view, geothermal energy is
  extremely price competitive in some areas and
  reduces reliance on fossil fuels and their
  inherent price unpredictability.

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Disadvantages

• Construction of the power plants can adversely
  affect land stability in the surrounding region.
• Dry steam and flash steam power plants also emit
  low levels of carbon dioxide, nitric oxide, and
  sulfur, although at roughly 5 of the levels
  emitted by fossil fuel power plants .

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We thank you!

• Made by
• Adascalitei Victor
• Coman Andrei
• Oaida Adrian
• Coordinated by
• Schnabel Dieter