3. Well design and corrosion zones

Figure  1 shows the basic elements for a LE geothermal design. Hot water is pumped to the surface from the water reservoir. An Electric Submersible Pump (ESP) is usually required to provide additional lifting power to bring the water to the surface. From the producer wells the hot water flows to the thermal power generator plant, commonly an Organic Rankine Cycle (ORC) design where heat energy from the produced water is transferred to an organic fluid with a lower boiling point than water. The organic fluid turns to vapor which is used to turn a turbine which generates electrical power. The water from the ORC plant is then discharged at a lower temperature to injector wells where it is sent back to the water reservoir.