Slide 1
Geothermal systems that pump water from the reservoir are termed hot water wells. With the flash plant the decrease in pressure that occurs when the water is brought to the surface causes it to boil and steam is separated from the water in the flash separator. The steam is then used to turn the turbines and the excess water is pumped back into the ground.
Slide 2
Because hydrothermal waters contain high concentrations of dissolved minerals which can corrode generators a binary plant is often used to tap the earths energy. The hot water from the reservoir is kept in a closed loop to prevent precipitation of dissolved solids. In a heat exchanger a secondary fluid is heated which is then used to generate the electricity.
Slide 3
Geothermal energy is also used directly to heat buildings.
Slide 4
Some areas have the necessary heat source but lack the permeability and water necessary for a hydrothermal resource. In this case two well are drilled and the rocks between them are fractured producing a heat exchange surface. Cold water is then pumped down one well and warm water is pumped up the other well.
Slide 5
  • Geothermal 6
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