Geothermal stream fields

The flashed steam method is less efficient and its requirements for steam properties—cleanliness, high temperature, and high pressure— are usually unavailable in most geothermal fields. The situation is different with the binary cycle system, which is quite efficient and widely used. This wet system involves the transfer of heat from the hot well stream into a more manageable boiling fluid to generate power through a turboexpander. 

Welch, D. (1999) Arsenic geochemistry of stream sediments associated with geothermal waters at La Primavera Geothermal Field, Mexico Master s Thesis. New Mexico Institute of Mining and Technology, Socorro, p. 91. 

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