Geothermal and Hydroelectric

Geothermal

Geothermal energy uses heat from within the Earth's surface to provide heat and generate electricity. There are currently three ways to generate electricity from geothermal resources:

• Dry steam power plants - In dry steam plants, dry steam is fed directly into a turbine for power production.
• Flash steam power plants - Flash steam plants use pressurized water from below ground to flash into steam to be run through the turbine with the excess water re-injected into the underground reservoir.
• Binary power plants - Binary power plants transfer the heat of the geothermal fluid to a separate "working" fluid, which boils to vapor and is directed into a turbine for power production.

Hydroelectric Power Technologies

Hydroelectric power uses the force of falling water to drive turbine generators to produce electricity.

• The simple workings of a hydropower plant have water flowing through a dam, which turns a turbine, which then turns a generator.
• The volume of water flow and the height (called the head) from the turbines in the power plant to the water surface created by the dam determines the quantity of electricity generated.

There is a decline in building new hydroelectric power plants because many of the best places to utilize rivers and other water habitats already have hydropower plants. California law also severely limits the types of hydroelectric power due to growing concerns about effects on fish, other wildlife and the environment. These facilities must be smaller than 30 MW and typically consist of hydro generators placed in water aqueducts.

On The Web

• Hydroelectric Power In California *
  
• U. S. Geological Survey: Hydroelectric Power *
  
• Hydroelectric Power for Kids *
  
• The Energy Planet *

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