Flash
tank
Turbine
Production
well
Injection
well
Rock layers
Generator
Load
(b)
Load
Turbine
Generator
Heat exchanger
with working fluid
Rock layers
Production
Injection

well
well

(c)
FIGURE 3.3 (Continued) Three methods of recovering geothermal energy: (b) flash steam and
(c) binary cycle. (Adapted from Union of Concerned Scientists, How Geothermal Energy Works,
Union of Concerned Scientists, Cambridge, MA, 2012; National Renewable Energy Laboratory.
Planta Solar 20. http://www.nrel.gov/csp/solarpaces/project_detail.cfm/projectID=39.)